Veterinary Collaboration and Modernization in the French Animal By-Products Industry, 1940–1944

Abstract

Scholars studying the Second World War animal by-products industry have underestimated the systematic nature and broad scope of German intervention. This article examines how the close co-operation between French and German veterinarians, reflecting a shared professional interest in animal slaughter and disease control, facilitated the large-scale restructuring and modernization of French carcass disposal under Nazi occupation from 1940 to 1944. Animal by-products were an important resource for Germany’s war effort. Drawing on the previously unexploited papers of Wehrmacht veterinarian Conrad Herbig and the archives of the Vichy Salvage Service, I argue that German veterinary officers, in collaboration with their French counterparts, leveraged their expertise to impose a new vision of hygienic and efficient rendering practices in France. Herbig’s experiences in the Indre-et-Loire department reveal how the Nazi occupation authorities harnessed French material and institutional resources to direct French hides, fats, and bones towards German military production, even as logistical constraints limited their ambitions. Franco-German veterinary collaboration under Vichy represented an intensification of long-term trends towards professionalization, industrial concentration, and hygienic regulation in the French meat industry. This microhistorical case-study thus sheds new light on the dynamics of the occupation and its post-war impact on French agriculture and food production.

As Allied forces advanced into Nazi-occupied France in June 1944, Wehrmacht veterinary officer Dr Conrad Herbig embarked on an unusual scouting expedition in the Loire River valley.¹ Armed not with a gun but with a camera and black-and-white film, he left his post in Tours to photograph the Indre-et-Loire department’s dozen knackers’ yards. These establishments processed dead animals, extracting hides, rendering fats, and producing fertilizer from the remaining carcasses. Herbig’s camera lens captured an often overlooked and misunderstood consequence of the Allied blockade and Nazi Germany’s ravenous demand for munitions: the mobilization of every scrap of animal remains for the war effort. Cattle feet provided torpedo oil.² Fats greased guns. And most important for Herbig’s mission, gelatine from bones coated the precious paper Herbig used to develop, print, and organize his photographs. After selecting the most ‘beautiful’ images, he compiled them into an album. What happened next comes as a surprise. Before the German army’s hasty retreat in August 1944, Herbig presented it to his French counterpart, departmental veterinarian Dr Émile-Darius Pécard. With Herbig’s signed dedication, ‘given in memory of his collaboration’, the album offered visual evidence of their joint efforts to improve the French carcass rendering industry, which both saw as unhygienic and inefficient.³

This episode, recorded in Herbig’s private papers, raises two central questions. First, why did Wehrmacht veterinarians devote so much time and energy to extracting such marginal economic resources for wartime production? Second, why did French veterinarians help them? Using Herbig and Pécard’s collaboration as a case-study, this article tries to answer these questions and, in the process, examines the history of slaughterhouse modernization and animal by-products recovery under Vichy. It argues that French and German veterinarians played a key role in the attempt to restructure and rationalize carcass disposal between 1940 and 1944. Though the ambitions of these veterinary modernizers were checked by constraints of energy and raw materials, their shared vision had important consequences for the post-war era.

Waste reclamation was in fact central to Nazi ideology. As historian Anne Berg has recently argued, Nazi waste experts married the ‘fantasy of a circular economy’ with notions of cleanliness and order. But the collaboration between French and German veterinarians suggest these ideas found resonance beyond Nazi ideological circles.⁴ For Berg, Germany’s need for soap and detergent – rather than munitions – provided the primary impetus for the collection of animal bones, claws, and hooves, thus revealing underlying irrational racial obsessions behind Nazi resource-extraction policies.⁵ Similar ‘purification fantasies’ could have motivated Herbig’s disgust at the filth in French slaughterhouses; as Robert Gildea points out, he repeatedly tried and failed to eradicate rat infestations.⁶ Yet Pécard and his veterinary colleagues in Tours, who were not committed Nazis, shared Herbig’s concern that unhygienic conditions could threaten public health. They also agreed that by-product recovery could be improved to avoid wasting potential resources.

In the nineteenth century, both French and German veterinarians had differentiated themselves from other animal healing occupations by developing specialized knowledge of contagious animal diseases.⁷ In both countries, veterinarians often enforced new sanitary regulations, making slaughterhouses sites of surveillance and control.⁸ Only in Germany, however, had animal slaughter come directly under the authority of civil-servant veterinarians.⁹ A unique relationship between state, economy, and national welfare after 1871 had allowed these veterinarians to create a ‘slaughter culture’ based on the technological, hygienic transformation of animal carcasses into marketable by-products. During the First World War and again after 1933, German veterinarians weaponized the idea of carcasses as untapped reservoirs of raw materials.¹⁰ French veterinarians did not.

Wehrmacht veterinary officers brought their carcass recovery expertise to occupied France in the summer of 1940. Before conscription, many had worked as slaughterhouse managers or meat inspectors; the younger officers had all completed mandatory slaughterhouse practica as veterinary students, including training in carcass rendering technology. These experiences led them to view rural France as both unclean and technologically inferior, a sentiment reinforced by their participation in a co-ordinated initiative in spring 1941 to document the supposedly outdated, inefficient machinery in French slaughterhouses and knackers’ yards. They conducted inspections, gathered statistics, and wrote reports describing the ‘mediocre’ technology with ‘insufficient’ recovery.¹¹ Such attitudes reflected a broader discourse among German agrarian experts. These men saw themselves as exemplars of a ‘modern’ Germany, ‘pioneers’ of a German colonial project aimed at integrating French rural life into the German continental economic empire.¹²

Although condescending in nature, these German assessments aligned with the views of some French veterinarians who themselves had long advocated for the modernization of animal slaughter and carcass processing. Recent scholarship has highlighted how slaughterhouse reform was led by both French and German veterinarians: Maurice Piettre and Henri Martel in France; Oskar Schwarz, Robert von Ostertag, and Erich Moegle in Germany.¹³ Before the First World War, European slaughterhouse experts admired Germany’s veterinarian-led abattoirs for their hygienic and technological innovations and encouraged other countries to emulate these models of progress.¹⁴ Even with the United States’ leadership in rendering technology by the 1930s, French reformers still favoured the German model because of its emphasis on hygiene, public health, and veterinary oversight. Thus, during the occupation, shared professional interests allowed French and German veterinarians to transcend national enmities, paradoxically facilitating processes of mutual observation, exchange, and ‘learning from the enemy’.¹⁵ This particular sectoral collaboration resulted from the failed pre-war advocacy of French veterinary experts coinciding with German interests in increasing food supplies and raw materials for Wehrmacht troops.¹⁶ French veterinary experts at last found a sympathetic audience for their concerns, while the Germans saw a way to increase needed food and military supplies. Veterinarians on both sides represent an overlooked group in the extensive literature on Franco-German technocratic exchange, which primarily focuses on state officials and business leaders.¹⁷

Though German veterinarians’ attempted ‘total’ recovery of carcass waste might seem to be a symptom of ideological ‘fantasies’ and economic dysfunction, it responded to real military demand. For Wehrmacht raw material experts, animal remains provided raw materials for a range of critical military needs. In 1940, some goods had no synthetic substitutes, like torpedo oil from cattle feet or the high-quality photographic gelatines from bones, whose supply the Wehrmacht had monopolized for aerial reconnaissance, mapping, and propaganda photographs.¹⁸ Preserving canned fish and meat in field rations for soldiers required edible gelatines, while glycerine, machine grease, and lubricants depended on a steady supply of animal fats.¹⁹ Hides furnished leather for combat boots, trench coats, belts, straps, and other essential equipment. Because many of these raw materials were not captured in import statistics or were later used by French companies carrying out German orders, they have largely escaped the notice of economic historians in their assessment of the contribution of the French economy for German military production.²⁰

A French veterinarian like Pécard clearly had no interest in provisioning the Wehrmacht with raw materials. But if collaborating with Herbig could prevent improperly disposed carcasses from causing disease or contaminating local water supplies, he was willing. Most of his colleagues behaved similarly. Some even went further. For veterinarians like Maurice Piettre or Henri Martel who had long advocated for improved technology and by-product recovery in French slaughterhouses and knackers’ yards, the occupation offered an unprecedented opportunity to achieve these goals.

By the time the Vichy regime implemented a national regulatory framework for animal carcasses in 1943, shortages of coal, gasoline, and means of transport hampered the German occupiers’ consolidation and modernization programme. However, after France’s liberation, local decrees that rationalized carcass recovery through distributed catchment areas and the extensive statistical information collected on animal slaughter during the occupation served as blueprints for post-war reform. These continuities suggest that French agrarian modernization, long seen as taking off only in the 1960s, owed much to Franco-German wartime co-operation.²¹

This microhistorical study of the modernization of the French carcass disposal industry traces the evolution of Franco-German veterinary co-operation from the early days of occupation through to its lasting impacts. It examines legislative efforts, implementation challenges, and the tension between hygienic reform and resource extraction. By exploring how shared professional interests operated during wartime, it also offers a more complex perspective on occupation dynamics than traditional narratives of collaboration and resistance. The unexpected Franco-German wartime co-operation among these veterinarians intensified long-term trends towards professionalization, industrial concentration, and regulation in the French meat industry.

I

France’s defeat in June 1940 led to severe shortages of animal by-products for French industry. The Allied blockade choked off imports, while transportation difficulties and fuel scarcity disrupted animal slaughter and rendering. In occupied areas, the German army deployed mobile economic commando units to requisition these materials. By the beginning of August, these units had identified, sequestered, and inventoried staggering amounts of animal matter: 50 tonnes of unrefined torpedo oil, 120 tonnes of glycerine, 1,120 tonnes of leather, 7,100 tonnes of industrial oils and fats, and 420,000 skins and furs.²² The occupying forces reserved the most valuable resources for themselves, using the remainder to compel the French to accept limited civilian production from domestically salvaged raw materials. This strategy transferred the burden of waste recovery to French industry and the Vichy regime.²³ The Wehrmacht’s control over much of the French meat supply forced the French to salvage animal by-products from reduced civilian slaughter, diseased carcasses, and municipal waste.²⁴ Consequently, the Germans sought to extract even more from the French economy by modernizing rendering technology and implementing new legislation on carcass recovery.

Oversight for this modernization programme came not from the German occupation administration’s economic division, but from its office of veterinary services. In July 1940, General Staff veterinarian Dr Walther Semmler (1884–1945) began directing Wehrmacht veterinary officers across occupied France to improve rendering operations. Concurrently, he pressured Camille Boussard, director of veterinary services at the French Ministry of Agriculture, to leverage the existing supervisory role of French veterinarians in animal slaughter to regulate the recovery of carcass by-products.

Before the German invasion, Boussard had already initiated measures in this direction. In August 1937, he drafted a request for departmental veterinarians to estimate the quantity and value of all by-products available in slaughterhouses. Boussard repeatedly attempted to determine the quantity and weight of meat processed in industrial abattoirs and private ‘killing yards’, as he struggled to collect accurate statistical data on meat inspections.²⁵ With the outbreak of war in autumn 1939, a survey of 125 French knackers’ yards revealed that a third had ceased operations due to the loss of owners, personnel, and vehicles to military service.²⁶ On 1 June 1940, just two weeks before the Germans occupied Paris, a French government decree required that anyone involved in melting or extracting fats, including knackers, maintain records of their stocks and regularly report them to the minister of supply. On that same day, Boussard instructed all departmental veterinarians to complete a detailed survey ‘to improve the efficiency of the rendering industry’.²⁷

When Semmler first met Boussard in the summer of 1940, he likely welcomed these prior initiatives, which facilitated his direct interventions, as suggested by Boussard’s subsequent actions. A 23 July decree expanded the 1 June requirement on tallow and fats to mandate monthly reporting of the total kilogrammes of ‘raw tallow, bones, carcasses or waste of land [and marine] animals…irrespective of their origin’, along with the quantity of by-products derived from that raw material.²⁸ In their regular meetings, Semmler pushed Boussard to implement new measures concerning rendering facilities, expressing frustration with the ‘too slow’ progress in maximizing by-product yields.²⁹

In August, Boussard prepared a report on the economic importance of animal carcasses, which his superior, Minister of Agriculture Pierre Caziot, forwarded to Marshall Philippe Pétain. To increase the ‘production of fats, fertilizers, and animal feed’, Boussard proposed a thirteen-article draft animal disposal law that sought to place carcass rendering under French veterinary control. It required the declaration of all dead animals, prohibited their incineration or burial, and subsidized their recovery by a local renderer through a new tax.³⁰ Similar provisions appeared in a decree enacted in occupied Belgium the following month, suggesting a shared German origin.³¹ From August to October, Boussard sent circulars instructing departmental veterinarians to address all veterinary matters of ‘a general order’ to himself and Semmler, provide monthly reports of all slaughtering activities to local German field commanders, and promptly complete the rendering survey requested on 1 June.³²

Boussard and Agriculture Minister Caziot’s efforts to establish a legislative framework for carcass recovery faced surprising resistance from Vichy. Despite Caziot’s signing of the draft law in August, Vichy’s Council of Ministers rejected its approval.³³ Instead, Pétain issued decrees targeting various animal by-products, aiming to provide for French civilian consumption. An internal directive encouraged the ‘salvage of scrap materials’ to ‘alleviate community suffering’.³⁴ Vichy laws in September and October banned the transformation of anything consumed by humans and animals into ‘non-food products’, mandated the supply of all cattle and pig pancreases to insulin manufacturers, and emphasized the recovery of food-grade fats and tallows.³⁵ Concurrently, the Ministry of Industrial Production’s chemical division instructed prefects to collect bones from household waste, ostensibly to mitigate soap shortages.³⁶

Initially, both Vichy legislation and leading veterinarians like Henri Martel, the former head of veterinary services in Paris, prioritized the allocation of animal by-products for civilian necessities. This was evidenced by Martel’s October 1940 proposal to collect the ‘torrents of blood’ from Parisian slaughterhouses for sausages and pig feed.³⁷ German interventions in late 1940, however, forced the Vichy regime to redirect animal carcasses and bones towards producing technical fats and oils, gelatines, and glues required for German wartime manufacturing.

In October 1940, German and French delegates met at the Ministry of Industrial Production in Paris to distribute available stocks of glues and gelatines. After extensive negotiations, the Germans agreed to accept 235 tonnes of the 474-tonne bone glue stock, as well as 40 per cent of future production, and set similar quotas for rabbit glue, gelatines, and hide glues. They acknowledged the military significance of these goods, emphasizing the importance of photographic gelatines to military operations and the prohibition of food gelatines in Germany due to wartime needs.³⁸ In the Franco-German accord on glues and gelatines signed on 15 and 16 January 1941, French negotiators secured assurances that bones from German troop slaughtering would be directed to French factories rather than Germany, and that future requisitions by German authorities would cease.³⁹

Such agreements formalized Germany’s policy of confiscating existing stocks and forcing the French to depend on recovered waste. By January 1941, the Germans had removed from France 126 tonnes of waste fat, 246 tonnes of gelatines, 369 tonnes of cattle tallow, 716 tonnes of bone glue, 2,919 tonnes of skins and hides, and 3,252 tonnes of unspecified various oils and fats.⁴⁰ The French glues and gelatines industry lost over half its reserves to Germany. To sustain production, both the French and Germans needed to procure bones and fats from slaughterhouses and knackers’ yards, but doing so required the intervention of French and German veterinarians.

II

From the onset of the occupation, the Wehrmacht veterinary services recognized the need to enlist the expertise and labour of French veterinarians, particularly concerning animal by-products. However, a major obstacle to this ‘indirect rule’ stemmed from differing practices and training in carcass disposal. German veterinary students, trained in meat inspection and processing technology, prepared for roles in managing abattoirs equipped with laboratories.⁴¹ Conversely, French veterinary students lacked such training or career prospects.⁴² While German veterinarians sought to limit carcass burial and optimize by-product recovery through technical means, French veterinarians saw carcasses as potential vectors of disease and thus advocated their burial in designated municipal plots. An examination of Conrad Herbig’s training, career, and initial efforts to improve rendering in the Indre-et-Loire department illustrates these contrasting attitudes of German and French veterinarians towards carcasses as well as their effects on everyday collaboration. Such differences were not easily overcome.

Prior to his deployment to France in the summer of 1940, Herbig had obtained extensive experience in slaughterhouses alongside his role as a course assistant at the Hannover Veterinary College. After receiving his veterinary licence in 1898, he prepared animal carcasses as a prosector at the Anatomical Institute and later earned a doctorate in microscopic anatomy. Herbig became a civil-servant veterinarian in 1906 and served in the army reserves, rising to the rank of chief veterinarian. Although his education predated curricular reforms mandating formal training in meat inspection and slaughterhouse management, Herbig worked for five years in the Hannover municipal abattoir and occasionally served as a temporary slaughterhouse director.⁴³ During the First World War, he was mobilized as a reserve staff officer and carried out duties related to meat inspection and by-product recovery in field slaughterhouses. Throughout the interwar period, Herbig continued to teach at the Hannover Veterinary College, where he witnessed the increasing alignment of the veterinary profession with Nazi ideals and militarization.⁴⁴

His slaughterhouse experience and veterinary education provided the frame through which Herbig would understand his role as a member of the German Wehrmacht. On 14 May 1940, he crossed the Dutch border, then advanced into Belgium and northern France with the invading German forces.⁴⁵ After the armistice, he was posted to the Field Command 528 in Tours, overseeing the Indre-et-Loire department. Like all veterinary officers stationed in occupied France, Herbig received orders to conduct reconnaissance on French veterinary conditions, personnel, and facilities under his command, including identifying slaughterhouses and knackers’ yards with ‘modern equipment for processing animal carcasses’, assessing local regulations governing their operations, and reporting on any orders regarding carcass disposal issued by individual military units.⁴⁶

To execute this mission, Herbig enlisted the support of the department’s seventeen non-mobilized French veterinarians, whose names he obtained in late June. A month later, Émile-Darius Pécard, head of the departmental veterinary services, sent Herbig a letter written in German requesting the repatriation of a colleague from a prisoner-of-war camp – the first of many requests that Herbig tried to accommodate.⁴⁷ Pécard then provided Herbig with a comprehensive report in French outlining the French veterinary administration, including the role of municipal veterinary health inspectors as ‘loyal collaborators’, responsible for meat inspections in both ‘public and private abattoirs’.⁴⁸ Pécard’s report aligned with information in a circular issued by the German veterinary services, detailing the training and licensing of French veterinarians, but it omitted any mention of carcass disposal or knackers’ yards, indicating that the French did not consider this activity to fall under veterinary control.⁴⁹

Herbig’s subsequent briefings underscored the differences between French and German practices. Based on what he later learned from Pécard, Herbig noted on 31 July that only the Tours slaughterhouse had modern rendering equipment, an outdated German-made Hartmann autoclave; that the department’s knackers’ yards had ‘almost anachronistic’ ‘primitive ovens’ for cooking chopped up carcasses; and that no local regulations governed these activities. A month later, Herbig described how French knackers were licensed by the prefect and subject to limited hygiene regulations but operated without designated catchment areas.⁵⁰ Despite the requirement to notify the nearest knacker of dead animals, carcasses were typically only retrieved for their hides if the price was favourable, with most being buried on private property – contrary to German practice. Herbig observed only one instance of recovering animal by-products other than hides: the Tours slaughterhouse produced ‘a small amount of carcass meal’.⁵¹ The decentralization of slaughter operations prevented any economies of scale, with local butchers using 215 different ‘killing yards’ scattered throughout the department (see Figure 1).⁵²

Figure 1. Map of the knackers’ yards, slaughterhouses, and killing yards documented by Herbig. Made by the author using QGIS and a shapefile from Victor Gay, ‘TRF-GIS Stata Package’, doi.org/10.7910/DVN/XRMIVP, Harvard Dataverse, V5, UNF:6:Qn9Vz9PUPi7IHN+ZDZYGSg== [fileUNF], 2021.

Source: Prefecture of Indre-et-Loire, ‘Liste des tueries particulières’ (undated), Archives départementales d’Indre-et-Loire, 1za/13, as well as ‘Aufstellung über Abdeckereien, Molkereien und Schlachthöfe im Departement Indre et Loire’ (undated) and ‘Projet d’arrêté’ (undated, c. 1 Apr. 1941), Archives départementales d’Indre-et-Loire, 1za/12.

Herbig’s findings reflected the situation across France, where animal carcass disposal was left to market forces, unlike Germany’s long, albeit inconsistent, history of regulation and public subsidies. French law did not mandate the declaration or processing of dead animals, and payment for these services varied based on proximity to a knacker’s yard, transportation, road conditions, and carcass value. A handful of well-equipped rendering plants near cities with glue or gelatines factories served industry directly with fats, oils, and bones, but most knackers simply removed hides and buried or burned carcasses. Departmental veterinarians like Pécard licensed and inspected knackers’ yards but avoided imposing stricter regulations. They feared that otherwise French knackers might go out of business, leading to improperly disposed animal carcasses triggering epidemics or polluting water sources.⁵³ Without comparable state support as in Germany, the French veterinarians’ professional oath ‘first do no harm’ trumped their duties as sanitary ‘police officers’.⁵⁴

This situation appalled Wehrmacht veterinarians like Herbig. They were accustomed to the stringent inspections conducted by civil-servant veterinarians in Germany’s public abattoirs, designed to separate the ‘clean’ and ‘dirty’ aspects of the slaughter and handling process. Lack of veterinary oversight and disregard for hygiene in French slaughterhouses regularly allowed ‘stomach and intestinal contents, blood, and other fluids [to splash] onto dressed carcasses ready for sale, exposing them to microbial contamination’.⁵⁵ Herbig’s inspection tour of slaughterhouses on 30 August revealed broken windows, walls that had not been cleaned and freshly whitewashed for decades, and the burning of pig carcasses in open pits. Despite his repeated requests for improvements, nothing had changed by December, prompting him to write to the prefect about the ‘dilapidated’ and ‘filthy’ facilities. Most alarming for Herbig, the collars and benches used to secure and slaughter the animals were coated in a putrid mixture of blood, fat, and faeces, ‘as thick as a finger’ – a potential health risk that could endanger ‘the entire population and thus also the German Wehrmacht’.⁵⁶

Herbig decided he needed empirical proof of this danger. Lacking the equipment to carry out the necessary scientific analysis, he sent a sample of the encrusted residue to a bacteriological lab in Tours run by French veterinarian Marcel Belin, who had studied at the Pasteur Institute in Paris.⁵⁷ Belin analysed the sample, found evidence of several dangerous bacteria, injected the culture into two guinea pigs, observed them until one died, and determined through dissection that the coli bacillus was the cause of death. He reported his findings to Herbig, who expressed his gratitude by requesting the repatriation of Belin’s son, a licensed veterinarian interned in a prisoner-of-war camp.⁵⁸

The collaboration between Belin, a French Pasteurian academic, and Herbig, a German civil-servant slaughterhouse specialist, had a significant impact beyond Tours. Belin’s findings featured prominently in the efforts of Wehrmacht veterinarians to address the inadequate hygiene controls in French animal slaughter and carcass disposal practices. In January 1941, Herbig included a summary of Belin’s bacteriological analysis in his situation report, which his superior then distributed to all veterinary officers in the south-western France military district, using it as justification for increased supervision over French slaughterhouses and knackers’ yards.⁵⁹

Wielding this scientific evidence with a French imprimatur, German veterinary officers soon embarked on a more aggressive campaign to modernize the animal by-products industry and bring it in line with German standards. Their collaboration with veterinarians like Pécard and Belin allowed this project to continue despite legislative delays and interference from other French authorities with jurisdiction over animal remains.

III

The salvage law of 23 January 1941 and the creation of Vichy’s Salvage Service established a legislative framework for controlling French waste within both occupied and non-occupied France.⁶⁰ The Service’s mandate was broad, encompassing various materials such as scrap metal, paper, rubber, and glass. However, in late January 1941, the Germans and French industry both had a pressing need for animal by-products. Michel Couturaud, the twenty-six-year-old employee assigned to carcass rendering, lacked experience beyond a two-year stint in a reclaim rubber company.⁶¹ Consequently, the responsibility for drafting carcass recovery legislation fell to several competing special interests, including Boussard’s Veterinary Services, the president of the Central Syndicate of French Renderers, and representatives of the chemical, leather, and animal feed industries within the Ministry of Industrial Production. Seemingly intractable disagreements among these stakeholders delayed the implementation of critical regulations, leading to a year-long impasse.

Unable to impose any national French legislation, Semmler leveraged his military authority in veterinary affairs to restructure carcass rendering at the departmental level. In early 1941, reports indicated that fuel shortages were disrupting the operations of most renderers and contributing to unsanitary conditions. In response, Semmler launched an initiative to maintain well-equipped knackers’ yards, close to those that only harvested the skins, and consolidate catchment areas.⁶² Yet implementation varied widely across occupied France, depending on the initiative of the individual German veterinary officer who received the orders and the willingness of the responsible French departmental veterinarian to co-operate, as documented in Herbig’s papers and Salvage Service correspondence.

In January 1941, Semmler conducted inspection tours that coincided with German visits to French knackers’ yards. The head Wehrmacht veterinary officer in Dijon, for example, reportedly complained to French veterinarians in Orléans and Auxerre about their ‘insufficient’ recovery of by-products.⁶³ Over the next several months, the Salvage Service met with local officials, renderers, and veterinarians throughout occupied France, confirming both widespread German intervention and the technical limitations of these operations.⁶⁴ Most facilities had open kettles and simple bone mills, only suited for transforming carcass waste into animal meal and fertilizer – a situation that had remained unchanged since Henri Martel’s 1912 study of carcass rendering.⁶⁵ In all the cities visited, Wehrmacht veterinary officers approached departmental veterinarians requesting statistics about animal slaughter and by-products, sometimes offering additional rations of coal or gasoline to restart operations. In Auxerre, they announced plans to import machinery from Germany to selected knackers’ yards, and by late February, divided the department into catchment districts with designated yards. The departmental veterinarian in Auxerre saw these initiatives as the initial stage of a systematic takeover.⁶⁶

From February to May of 1941, French departmental veterinarians in the occupied zone took the initiative to advocate for decrees regulating knackers’ yards, motivated by a combination of self-interest, business lobbying, and German pressure. Some perceived German intervention in animal by-products as a threat, while others saw it as an opportunity. The head veterinarian of the Aube department, hoping to secure double fuel rations for knackers, drafted the first of these decrees, which banned carcass burial, designated official carcass renderers, divided them into districts, and required carcasses to be declared and picked up within twenty-four hours – all stipulations included in Boussard’s August 1940 proposal. On 11 February, the head of the chemical division of the Ministry of Industrial Production forwarded a copy to all prefects in the occupied zone, resulting in the adoption of the Aube decree almost verbatim by several other departments over the next few months.⁶⁷ The rapid spread of decrees based on the Aube model reflected the growing influence of German priorities on the French rendering industry, even as French veterinarians sought to maintain some degree of autonomy and control.

A document in Herbig’s papers reveals that the seemingly individual initiatives by French departmental veterinarians were part of a co-ordinated German programme. A 21 February circular from Herbig’s superior in Angers outlined the German military administration’s plan to maintain and ‘possibly develop’ only the ‘really useful’ knackers’ yards. The circular requested specific information about the capacity of autoclaves, maximum carcass processing amounts, transport and storage facilities, and fuel requirements. Additionally, it suggested that owners of the dead animals be compensated ‘according to the German model’, with payment scales determined by the responsible French departmental veterinarian.⁶⁸

Herbig believed that none of the rendering operations in his department, except for the Tours slaughterhouse, qualified as ‘really useful’. Perhaps for this reason, he delayed responding to the circular until he received another copy on 27 March, with a note to ‘hurry up’ pencilled in red.⁶⁹ Pécard provided the requested information, which Herbig incorporated into his report describing the squalid conditions of the knackers’ yards. The ‘puny and primitive facilities’ consisted of just a few dingy rooms for skinning, cutting, and salting hides, and open-air sheds for maceration and fat boiling, while carcass parts, covered in lime, decomposed in brick pits before being shovelled against a sieve to separate the bones. Despite these conditions, Herbig took the first steps to rationalize this industry by including a German translation of a prefectural decree that created catchment areas (see Figure 2) like those in the Aube department. The decree included additional specifications for the recovery of carcass material and exemptions for the burial of diseased animals. A comparison of Herbig’s revisions to the German text with the French draft decree suggests that he initiated the order.⁷⁰ Herbig’s actions demonstrate the extent to which German authorities could shape French regulations to align with their own priorities, even at the local level.

Figure 2. Recreation of Herbig’s proposed catchment areas (April 1941). Made by the author using QGIS and a shapefile from Victor Gay, ‘TRF-GIS Stata Package’, doi.org/10.7910/DVN/XRMIVP, Harvard Dataverse, V5, UNF:6:Qn9Vz9PUPi7IHN+ZDZYGSg== [fileUNF], 2021.

Source: the list of communes included in each district came from ‘Projet d’arrêté’ (undated, c. 1 Apr. 1941), Archives départementales d’Indre-et-Loire, 1za/12.

The sluggish response to the 21 February circular by veterinarians like Herbig prompted the German military administration in Paris to issue a subsequent order on 10 April, requiring veterinary officers to shut down inadequately equipped knackers’ yards and reallocate scarce fuel and coal to those that remained open. Semmler then carried out a second inspection tour, meeting Herbig on 19 and 25 May, before convening a two-day conference with all veterinary officers in northern France in June. During the conference, the veterinarians discussed the need to establish designated renderers with catchment areas, and Semmler announced that the Vichy government would soon enact comprehensive carcass disposal legislation. Herbig noted in the margin of his conference agenda to ask Pécard about the legislation, but upon returning to Tours, he discovered that nothing had been decided.⁷¹

This absence of comprehensive French legislation reflected the deep divisions within the Vichy government over who should benefit from carcass recovery. After animal feed producers lost out to the glues and gelatines industry, a tug-of-war emerged between Vichy’s economic control organizations and Boussard’s Veterinary Services over hygienic regulations that clearly reflected a larger disagreement among their respective German overseers.

But Semmler finally got what he wanted when the law on ‘the rendering of animals’ was signed in Vichy on 2 February 1942.⁷² Although it resolved some contentious issues between the French veterinary services and the animal by-products industries, the law remained incomplete, deferring questions of hygiene and technical processes for future regulations. The law’s nineteen articles showed only minor modifications from the draft that Semmler had pressed Boussard to prepare in August 1940, which Pétain had refused to sign. These modifications included a requirement to bury smaller carcasses in communal plots with strict hygienic supervision (a concession to French veterinarians), clarification of mayoral duties, a limited role for commercial interests, a reduction of the weight of targeted carcasses from 100 to 75 kilogrammes, and – the most significant change – a ten-fold increase in the fines for non-compliance.

This law marked the first step towards modernizing carcass disposal in France, bringing it closer to the established practice in Germany. Although, as Herbig had repeatedly emphasized, few French knackers had the necessary technical capacities required to meet German expectations.

IV

The enactment of the February 1942 law marked a turning point in the regulation of the French rendering industry, but its implementation proved to be a contentious and protracted process as French and German officials grappled with the realities of wartime shortages, inadequate infrastructure, and conflicting priorities. In June 1942, Maurice Piettre, a prominent French academic veterinarian, found it ‘unacceptable’ that knackers’ yards were not required to ‘receive and ensure the regular removal and treatment of slaughterhouse residues’. He demanded an ‘immediate measure’ requiring catchment areas and ‘modest subsidies’ to recover the ‘hundreds of tonnes’ of ‘fats, bones, manes, wool, skins, [and] bile…wasted every week’.⁷³ A month earlier, the German military administration in Paris noted that the law’s enforcement had been hindered by fuel shortages and the limited number of local authorities, such as veterinarians, who understood the ‘epidemiological, health, and economic importance of proper rendering’.⁷⁴ The German occupation of the southern zone in November 1942 only worsened these deficits.

Improving the situation required further legislation, significant resources, and co-operation at the highest levels between French and German experts. After more than two and a half years of work, the implementing regulations on rendering facilities were signed in Vichy on 17, 18, and 19 March 1943 as three decrees. The first decree regulated hygienic conditions, the second provided exceptions for renderers without proper equipment, and the third detailed treatment processes and monthly reporting obligations for by-products.⁷⁵ The German imprint on the regulations was particularly evident in articles 2 through 7 and 12 of the first decree.⁷⁶ These articles mandated the separation of rendering facilities into ‘clean’ and ‘dirty’ zones, with walls on all sides, ventilation, and adequate lighting. They also required rendering to be done in closed machinery that treated and dried carcass material with heat and prevented the spread of flies. These guidelines – approved by Boussard’s Veterinary Services – aimed to address the unhygienic conditions that German veterinary officers like Herbig had observed in French facilities in 1940 and 1941. They also mirrored similar changes to a set of ‘general instructions for the establishment of public and industrial abattoirs’ adopted by the French Superior Council of Public Hygiene in October 1942.⁷⁷

Despite considering the improvement of the department’s rural knackers’ yards ‘completely futile’, Herbig found more success in exploiting animal by-products for German military needs in Tours.⁷⁸ In June 1942, he became responsible for a newly established army slaughter unit that worked alongside the French in Tours’s municipal slaughterhouse. With the help of the mayor and Pécard, he addressed several ‘gross violations of cleanliness’ by having all the broken windows replaced and supervising ‘extensive repairs’ to the sewage system.⁷⁹ Although Herbig had previously disparaged the condition of these facilities, they clearly served his purpose. The slaughter unit processed around 200 animals every month, recovering increasing amounts of by-products from 50 tonnes of carcass material. From June to December 1942, the unit shipped more than 4 tonnes of tallow, 589 cattle heads used for making gelatines, and 1,036 bundles of cattle feet designated for refining into torpedo oil to Wehrmacht collection centres in Nantes and Paris.⁸⁰

As German military needs evolved, the by-products targeted shifted over time. After the deployment of a synthetic substitute for torpedo oil in 1942, collecting cattle feet became less important, while in 1943 the fat contained in tallow and bones gained significance as demand in Germany continued to outstrip supply even though synthetic fats and detergents accounted for nearly half of German industrial fat consumption.⁸¹ In August 1943, Semmler informed Herbig that experts from the Reich Economics Ministry had been sent to France to address a looming shortage of fats needed for soap-making. German veterinarian Erich Moegle was tasked with increasing fat production from animal carcasses and required information on the status of knackers’ yards in each department.⁸² As usual, Pécard supplied the information, and Herbig reported on the limited number of carcasses processed, the inadequate transportation, and the poor condition of the buildings that made costly upgrades ‘not worthwhile’.⁸³ Later, Herbig sent a map marking the location of each knackers’ yard, stating that, with the exception of the slaughterhouse in Tours, none had an autoclave, and equipping them with modern machinery was ‘impossible’.⁸⁴

In October 1943, Herbig received Moegle’s comprehensive thirteen-page report on the state of the French rendering industry. Despite now having a legislative framework in place for an extensive modernization programme, Moegle concluded that equipping all 500 knackers' yards in France with new machinery was unfeasible. Instead, he proposed a three-part plan: first, constructing fifteen new facilities where they were entirely lacking (mostly in southern France); second, consolidating the industry by providing additional fuel and vehicles to the 190 operations equipped with autoclaves; and finally, gradually shutting down the remaining facilities.⁸⁵ The map accompanying his report (Figure 3) clearly showed that very few of these facilities were located in the so-called Free Zone, which was controlled by the Vichy regime from 1940 to 1942. This lack, however, had more to do with the relative distribution of large farm animals (Figure 4) than with the larger German presence in northern and western France.

Figure 3. Moegle’s map of rendering facilities in France. The legend explains from top to bottom that what appears in this grayscale version as white dots are used for rendering plants with ‘complete machinery’, grey dots for those with only autoclaves, black dots for knackers’ yards without machines, and pencilled X’s for places where new facilities are needed.

Source: ‘Karte von Verwertungsanstalten’, Hauptstaatsarchiv Stuttgart, EA 2/150.

Figure 4. The relative distribution of farm animals in France in 1942. Made by the author using QGIS and a shapefile from Victor Gay, ‘TRF-GIS Stata Package’, doi.org/10.7910/DVN/XRMIVP, Harvard Dataverse, V5, UNF:6:Qn9Vz9PUPi7IHN+ZDZYGSg== [fileUNF], 2021.

Source: Statistique Générale de la France, Annuaire statistique, vol. 56, 1940–5 (Paris, 1946), pp. 119–20, available at gallica.bnf.fr/ark:/12148/bpt6k6424260x/f158.item.

To carry out this work, Moegle advised creating a seven-person technical committee consisting of representatives from the French Veterinary Services and the Ministry of Industrial Production. However, as chair of this committee, Moegle indirectly recommended André Vincent, the president of the French renderers syndicate, who had helped him prepare the report, rather than Boussard, whom he had met in March 1942. Boussard had declined Moegle’s invitation to inspect rendering machinery in Metz and Strasbourg in May 1942 stating that there was ‘neither money nor material for the construction of new rendering plants’.⁸⁶ He confidentially told the Salvage Service he had refused because he feared making French agriculture dependent on German technology.⁸⁷

Even with Boussard’s reluctance, the Vichy regime endorsed Moegle’s modernization project. In April 1943, the Salvage Service issued a circular requesting their delegates to work with departmental veterinarians in preparing reports on the state of carcass rendering facilities in each region.⁸⁸ The following September, the Ministry of Industrial Production’s division of chemical industries dispatched Maurice Piettre to survey French slaughterhouses, knackers’ yards, and clandestine butchering practices in northern, western, and south-western France.

In March 1944, Piettre presented his findings at a meeting of the Academy of French Agriculture. He praised the ‘remarkable’ industrial and nutritional output achieved in the German-controlled sections of French slaughterhouses, suggesting that it should ‘inspire our military quartermasters or even civilians’. Yet Piettre reserved his highest praise for Vincent, who had collaborated with Moegle for sixteen months to determine which of the 550 French knackers’ yards needed to be closed, how the 350 ‘suitably equipped’ operations should be ‘judiciously distributed’, and how to upgrade an additional 140 facilities using 840 tonnes of metal allocated by the Germans. Piettre cited the example of an old knacker’s yard in Rennes, which had been ‘remarkably modernized’, enabling ‘a better recovery of fats’.⁸⁹ In April 1944, Vincent was appointed as the delegate general of a new ‘organization committee’ for the rendering industry, and in May, he joined the consultative committee to the Salvage Service.⁹⁰ Through these efforts, German veterinarians had successfully imposed their vision of carcass recovery on the French without necessarily carrying out the work themselves.

Because this textbook example of ‘indirect rule’ through proxies was achieved only as the war entered its final months and the prospect of Allied victory loomed, it had a more significant impact on France’s post-war reconstruction than on Germany’s war economy. Piettre concluded his presentation by calling for ‘a severe post-war [by-product] recovery policy’. He explained that ‘the state of destitution where we will be at peace’ meant that France could not afford ‘to waste or lose enormous masse…of products so precious for human and animal food and the manufacture of fertilizers for the food industries’.⁹¹ That same month, the secretary general at the Ministry of Agriculture announced a ‘survey relative to the establishment of an equipment plan for the country in abattoirs’. The circular acknowledged the material limitations of implementing any new ‘equipment plan’ in the immediate future but emphasized the need to lay the groundwork for the post-war period. Similar to Moegle’s project to modernize knackers’ yards, it requested extensive statistical and cartographic information from departmental authorities, including veterinarians. Echoing Piettre’s call to action, its key economic principle emphasized the ‘total salvage of the fifth quarter’, an expression referring to the edible and industrial by-products of animal slaughter.⁹² The project’s time horizon assumed that this waste-nothing approach to animal utilization, a consequence of Franco-German collaboration, would continue long after the war.

In the final months of the war, the Germans clung to this ‘zero waste’ ideal despite increasing evidence by veterinary officers on the ground of its impracticality. In Tours, for instance, Herbig had to conduct six in-person inspections of the department’s knackers’ yards each month, despite rationed fuel and limited train connections. Even as he and Pécard recorded the amounts of bones and fats waiting to be picked up at each location, they lacked the means to redirect those materials to industry. When asked in March 1944 whether animal blood could be collected ‘for technical purposes’, Herbig had to explain, once again, that he lacked the proper equipment.⁹³ In response to Moegle’s October 1943 report insisting on modernizing the rendering industry, Herbig conceded that one knacker’s yard in Sainte-Maure might be a plausible candidate, but only if an entirely new building were constructed – an impossibility given the extreme resource shortages at that time.⁹⁴

Quantitative data from the archives of the Paris branch of the Reich Office for Animals and Animal Products suggest that Herbig’s experience in the Indre-et-Loire department may have differed from that of his counterparts stationed elsewhere, in areas with proportionally more farm animals (Figure 4). In spring 1944, the office initiated a last-ditch effort to maximize by-product recovery by conducting a final survey of the technical capacities of French knackers’ yards. The completed surveys for the northern France military district represent 165 of the roughly 500 operations in France. Although the Indre-et-Loire department was not included, as it belonged to the neighbouring south-west France district, the survey found that each of the fifteen departments in the district had knackers’ yards similar to those observed by Herbig, but at least one operation in each department had modern machinery, including autoclaves, dryers, or fat separators. A comparison with the data from Moegle’s October 1943 map (Figure 3) shows an increase in the number of equipped facilities in the region – confirming Piettre’s observations from his investigation. Herbig’s experience, however, implies that limitations of fuel and transport probably impacted the ability of Germany to benefit from these technological upgrades, particularly following the Allied invasion.

Herbig’s final inspection tour in June 1944 may have been an attempt to convince his superiors in Paris of the folly of modernizing the facilities in his department. Unlike his previous visits, he took a camera and documented each of the twelve knackers’ yards in the region, intending to create a report on their size, importance, equipment, and other features.⁹⁵ Although Herbig never completed this project, he managed to develop the film, print the pictures, and include them in his papers – a surprising feat given the shortages of photographic gelatines and film due to insufficient by-product recovery. These photographs (Figure 5) provide a vivid glimpse into Herbig’s perception of France as a technologically inferior and unclean society, depicting piles of decaying horse carcasses, a bloody hindquarter lying on a concrete floor, and a brick oven with a chimney poking through a worn, corrugated metal roof. Nevertheless, Herbig clearly felt that his counterpart, Pécard, shared this vision. In a handwritten note on the file folder containing the photographs, Jean Massiet du Biest, the archivist of the Indre-et-Loire who recovered Herbig’s papers in August 1944, explained that Pécard showed him ‘an album with a dedication containing a much more beautiful and more complete collection of these photos with explanatory captions given in memory of his collaboration and signed by Dr Herbig’.⁹⁶ When Herbig hastily retreated from Tours in August 1944, leaving everything behind, he could nonetheless take comfort in knowing that Pécard might continue the work they had started together.

Figure 5. Photographs of the Restigné and Comery knackers’ yards taken by Herbig (undated).

Source: Archives départementales d’Indre-et-Loire, 1za/2. Efforts to locate living descendants of Herbig who may claim to be the rightful copyrightholder of these images have been made but without success.

After the war’s end, many of Pécard’s French veterinary colleagues advanced the modernization agenda set during the occupation. The Ministry of Agriculture continued gathering information for the abattoir equipment programme into June 1945 and used maps like Moegle’s to restructure meat production geography.⁹⁷ When the abattoir modernization commission convened in 1947, prominent veterinarians like Piettre and Martel were key members.⁹⁸ Amendments in 1945, 1949, and 1955 modified the 1942 rendering law, balancing increased oversight with market flexibility, allowing knackers’ yards to sell unsterilized raw meat to the growing number of fish and mink farms. These reforms drove a significant transformation in the industry. André Vincent’s son’s 1956 veterinary dissertation documented this change: the number of knackers’ yards decreased from 882 in 1912 to 438 in 1955, all equipped with modern steam pressure machinery.⁹⁹ The younger Vincent’s choice to study this topic in veterinary science rather than business management reflects how deeply intertwined veterinary expertise and by-product recovery had become – a direct legacy of wartime collaboration.

V

This study suggests how from 1940 to 1944, French and German veterinarians interacted with each other in ways that complicate simplistic narratives of resistance and collaboration. Their encounter also sheds light on three key features of the German occupation: the nature of Franco-German professional co-operation, the challenges of resource extraction, and the long-term impact on French agricultural modernization.

The attempt to modernize and rationalize the French animal by-products industry through Franco-German veterinary collaboration yielded mixed results. While Herbig’s experience in the Indre-et-Loire department suggests failure, Moegle’s broader survey reveals partial successes elsewhere. This ‘indirect rule’ relied on mutual benefits: French veterinarians gained increased authority and the repatriation of colleagues, while Germans accessed local expertise and resources. However, differences in training and professionalization limited the extent of technological transfer. Significantly, collaboration often resulted from shared professional concerns about hygiene and public health rather than from either ideological alignment or economic motivations.

This study also underscores the importance of considering waste collection and by-product recovery in evaluating German economic mobilization of occupied territories – an aspect usually neglected in broader historical narratives. Economic historians have long sought to explain how Nazi Germany defied Allied expectations that the blockade would cripple its wartime production. Their research has shown that Germany’s resilience stemmed from success in finding substitutes for imports and exploiting occupied territories.¹⁰⁰ Despite challenges posed by material scarcity, logistical obstacles, and entrenched local practices, animal by-products from knackers’ yards clearly contributed to the German war effort. Bones, fats, and animal feed played a part in sustaining German industry, even if their exact impact remains difficult to quantify due to incomplete statistical documentation. France provided 9 per cent of Germany’s meat needs by 1942, though the specific role of knackers’ yards in the 45,000 tonnes of fats exported that year remains unclear.¹⁰¹

Perhaps the most significant outcome of this collaboration was its lasting impact on French agricultural modernization. The wartime experience fostered shared assumptions and aspirations among French and German veterinary professionals that persisted well beyond 1945.¹⁰² This pattern aligns with Margot Lyautey’s findings on broader agricultural reforms, where French experts who collaborated with Germans during the occupation later became key figures in post-war modernization efforts.¹⁰³ In the animal by-products sector, the 1942 rendering law, though difficult to implement during the war, provided a framework for subsequent reforms. Its incorporation into the 1955 Rural Code and further expansion in 1976 demonstrate the enduring influence of wartime initiatives.¹⁰⁴

This microhistory of veterinary collaboration shows how professional networks and shared technical knowledge can transcend national borders even during wartime, shaping both occupation policies and post-war developments. It challenges us to reconsider the nature of collaboration and resistance, revealing a more complicated picture of professional interactions under occupation. By examining the often-overlooked sector of animal by-products, it contributes to a better understanding of economic exploitation and modernization in occupied France, while highlighting the continuities between wartime initiatives and peacetime practices. Ultimately, it suggests how the exigencies of war can catalyse unexpected long-term transformations, with professional expertise serving as a conduit for change across political and temporal boundaries.