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Replacement of conventional feedstuffs with cheap non-conventional ingredients may improve livestock performance and the quality of their products, particularly milk. The study considered the effects of Moringa oleifera (MO) foliage in replacement of berseem clover (BC) on feed utilisation and lactational performance in Nubian goats. A total of 16 lactating Nubian does, weighing 36.2±0.8 kg, were randomly assigned to four experimental treatments containing 0, 125, 250 and 375 g of MO per kg diet to replace 0 (M0), 25 (M25), 50 (M50) and 75% (M75) of BC (on dry matter (DM) basis) in a quadruplicated 4×4 Latin square design. The MO diets increased (P<0.01) feed intake and nutrient digestibility. Feeding MO diets improved (P<0.01) ruminal volatile fatty acids, acetate and propionate but reduced (P<0.01) valerate and iso-butyrate. Moringa diets increased (P<0.01) serum total protein, albumin and glucose but decreased (P<0.05) cholesterol and triglycerides. Milk yield and energy corrected milk, and milk total solids, fat and energy content were increased (P<0.01) in MO diets. Yields of milk components and energy were greater (P<0.05) for MO diets than for control diet. Milk total saturated fatty acids and athrogenicity index were lower (P<0.01), and unsaturated fatty acids, conjugated fatty acids and UFA/SFA ratio higher (P<0.05) for MO diets. It is concluded that feeding MO to replace 75% DM of BC improved feed utilisation, ruminal fermentation, and milk yield and quality in lactating Nubian goats.
Genetic improvement in production efficiency traits can also drive reduction in greenhouse gas emissions. This study used international ‘best-practice’ methodology to quantify the improvements in system-wide CO2 equivalent emissions per unit of genetic progress in the Irish Maternal Replacement (MR) and Terminal (T) beef cattle indexes. Effects of each index trait on system gross emissions (GE) and system emissions intensity (EI) were modelled by estimating effects of trait changes on per-animal feed consumption and associated methane production, per-animal meat production and numbers of animals in the system. Trait responses to index selection were predicted from linear regression of individual bull estimated breeding values for each index trait on their MR or T index value, and the resulting regression coefficients were used to calculate trait-wise responses in GE and EI from index selection. Summed over all trait responses, the MR index was predicted to reduce system GE by 0.810 kg CO2e/breeding cow per year per € index and system EI by 0.009 kg CO2e/kg meat per breeding cow per year per € index. These reductions were mainly driven by improvements in cow survival, reduced mature cow maintenance feed requirements, shorter calving interval and reduced offspring mortality. The T index was predicted to reduce system EI by 0.021 kg CO2e/kg meat per breeding cow per year per € index, driven by increased meat production from improvements in carcass weight, conformation and fat. Implications for incorporating an EI reduction index to the current production indexes and long-term projections for national breeding programs are discussed.
Suckling lamb meat is traditionally produced in Mediterranean Europe. Breed can affect the quality of the lamb carcass and meat. This study is aimed at comparing the carcass and meat quality between suckling lambs from a local and a non-native dairy breed, Churra and Assaf. Churra is included in the Spanish Protected Geographical Indication (PGI) ‘Lechazo de Castilla y León’, whereas Assaf is not. However, Assaf breeders have requested the inclusion of the breed in the PGI. Carcasses and meat from 16 male lambs (eight Churra and eight Assaf) were used in this study. The lambs were all raised under an intensive rearing system and fed on a milk substitute to minimise maternal influence. The carcasses were evaluated for conformation, fatness, joint and leg tissue proportions and the meat was analysed for composition (i.e. proximate composition, iron, haematin, fatty acids and volatiles) and technological quality traits (i.e. texture, water holding capacity, colour and lipid stability). Churra carcasses were larger than Assaf carcasses. However, the proportions of commercial joints and main tissues did not differ between breeds. Cavity and intermuscular leg fat, but not total leg fat, were higher in Churra carcasses. Churra meat showed a higher proportion of n-6 fatty acids, higher redness and better colour stability during aerobic storage. In contrast, Assaf lamb was more resistant to lipid oxidation after cooking. This is a preliminary study to measure the influence of breed on a wide range of quality characteristics in Churra and Assaf suckling lamb carcass and meat. It may be of relevance for breeders, consumers and food policy makers, setting the basis for future studies that include larger commercial populations.
The aim of this study was to evaluate the effect of using different floor types to accommodate growing and finishing beef cattle on their performance, cleanliness, carcass characteristics and meat quality. In total, 80 dairy origin young bulls (mean initial live weight 224 kg (SD=28.4 kg)) were divided into 20 blocks with four animals each according to live weight. The total duration of the experimental period was 204 days. The first 101 days was defined as the growing period, with the remainder of the study defined as the finishing period. Cattle were randomly assigned within blocks to one of four floor type treatments, which included fully slatted flooring throughout the entire experimental period (CS); fully slatted flooring covered with rubber strips throughout the entire experimental period (RS); fully slatted flooring during the growing period and moved to a solid floor covered with straw bedding during the finishing period (CS-S) and fully slatted flooring during the growing period and moved to fully slatted flooring covered with rubber strips during the finishing period (CS-RS). Bulls were offered ad libitum grass silage supplemented with concentrates during the growing period. During the finishing period, bulls were offered concentrates supplemented with chopped barley straw. There was no significant effect of floor type on total dry matter intake (DMI), feed conversion ratio, daily live weight gain or back fat depth during the growing and finishing periods. Compared with bulls accommodated on CS, RS and CS-RS, bulls accommodated on CS-S had a significantly lower straw DMI (P<0.01). Although bulls accommodated on CS and CS-S were significantly dirtier compared with those accommodated on RS and CS-RS on days 50 (P<0.05) and 151 (P<0.01), there was no effect of floor type on the cleanliness of bulls at the end of the growing and finishing periods. There was also no significant effect of floor type on carcass characteristics or meat quality. However, bulls accommodated on CS-S had a tendency for less channel, cod and kidney fat (P=0.084) compared with those accommodated on CS, RS and CS-RS. Overall, floor type had no effect on the performance, cleanliness, carcass characteristics or meat quality of growing or finishing beef cattle.
Developing countries are experiencing an increase in total demand for livestock commodities, as populations and per capita demands increase. Increased production is therefore required to meet this demand and maintain food security. Production increases will lead to proportionate increases in greenhouse gas (GHG) emissions unless offset by reductions in the emissions intensity (Ei) (i.e. the amount of GHG emitted per kg of commodity produced) of livestock production. It is therefore important to identify measures that can increase production whilst reducing Ei cost-effectively. This paper seeks to do this for smallholder agro-pastoral cattle systems in Senegal; ranging from low input to semi-intensified, they are representative of a large proportion of the national cattle production. Specifically, it identifies a shortlist of mitigation measures with potential for application to the various herd systems and estimates their GHG emissions abatement potential (using the Global Livestock Environmental Assessment Model) and cost-effectiveness. Limitations and future requirements are identified and discussed. This paper demonstrates that the Ei of meat and milk from livestock systems in a developing region can be reduced through measures that would also benefit food security, many of which are likely to be cost-beneficial. The ability to make such quantification can assist future sustainable development efforts.
The objective of this experiment was to establish the effect of low-concentrate (LC) and high-concentrate (HC) supplementation in the early and late periods of lactation on milk production and cow traffic in a pasture-based automatic milking (AM) system. In total, 40 cows (10 primiparous and 30 multiparous) were randomly assigned to one of the two treatments. The experimental periods for the early and late lactation trials extended from 23 February to 12 April 2015 and 31 August to 18 October 2015, respectively (49 days in each trial period). The early lactation supplement levels were 2.3 and 4.4 kg/cow per day for LC and HC, respectively, whereas the late lactation supplement levels were 0.5 and 2.7 kg/cow per day for LC and HC, respectively. Variables measured included milking frequency, milking interval, milking outcome and milking characteristics, milk yield/visit and per day, wait time/visit and per day, return time/visit and the distribution of gate passes. As the herd was seasonal (spring) calving, the experimental periods could not run concurrently and as a result no statistical comparison between the periods was conducted. There was no significant effect of treatment in the early lactation period on any of the milk production, milking characteristics or cow traffic variables. However, treatment did significantly affect the distribution of gate passes, with the HC cows recording significantly more gate passes in the hours preceding the gate time change such as hours 7 (P<0.01), 15 (P<0.05), 20, 21 (P<0.001), and 22 (P<0.05), whereas the LC treatment recorded significantly more gate passes in the hours succeeding the gate time change, such as time points 2 (P<0.01) and 10 (P<0.05). There was a significant effect of treatment in late lactation, with HC having a greater milk yield (P<0.01), milking duration and activity/day (P<0.05), while also having a significantly shorter milking interval (P<0.05) and return time/visit (P<0.01). The distribution of gate passes were similar to the early lactation period, with HC also recording a significantly greater number of gate passes during the early morning period (P<0.01) when visitations were at their lowest. Any decision regarding the supplementing of dairy cows with concentrates needs to be examined from an economic perspective, to establish if the milk production and cow traffic benefits displayed in late lactation outweigh the cost of the concentrate; thereby ensuring that the decision to supplement is financially prudent.
An isotope dose technique was utilized (i) to determine endogenous amino acid (AA) and protein losses and (ii) to propose adjusted values for AA requirements. The endogenous flow rate was calculated from the pool of enrichment in plasma AA, assuming similitude to enrichment of endogenous AA. In experiment 1, chicks were orally administered D4-lysine at 2% of estimated lysine intake from 16 to 24 days to find the isotopic steady state of the atom percent excess (APE) of lysine for plasma and jejunal and ileal digesta. The APE of D4-lysine in plasma, jejunal digesta and ileal digesta reached the isotopic steady state at 5.5, 3.4 and 2.0 days, respectively, by using the broken-line model. It was assumed that the isotopic steady state at 5 days identified for D4-lysine is also representative for the 15N-labeled AA. In experiment 2, chicks were fed diets from 1 to 21 days with increasing levels of fat (6%, 8%, 12%, 13% extract ether), protein (26%, 28.5%, 31% CP) or fiber (14%, 16%, 18% NDF) by adding poultry fat, soybean meal, blended animal protein or barley. Chicks were orally administered 15N-threonine, 15N-cysteine, 15N-methionine, 15N-lysine and 15N-leucine at 2% of estimated daily intake for 5 days from 17 to 21 days of age. Dietary nutrients influenced endogenous losses (EL), where dietary fat stimulated EL of lysine (P=0.06), leucine and protein (P=0.07); dietary protein enhanced EL of leucine and protein; and finally the dietary fiber increased EL of leucine. Dietary nutrients also affected apparent ileal digestibility (AID). Dietary fat increased AID of cysteine but decreased AID of lysine. Dietary protein reduced AID of protein, threonine, lysine and leucine, and similarly dietary fiber decreased AID of protein, threonine, methionine, lysine and leucine. In contrast, dietary fat or protein did not affect real ileal digestibility (RID) of protein and AA except threonine and leucine. The dietary fiber reduced the RID of protein, threonine and leucine. This indicate that variations of some endogenous AA and protein losses due to dietary nutrients almost eliminates the effects of RID, and thus the EL coming from the body should be utilized to adjust the AA requirement instead of changing the true digestible nutrients of ingredients. The present data suggest that 5 days’ feeding labeled AA was enough to reach the isotopic steady state and AA requirements should be adjusted when additional dietary protein, fat or fiber is fed.
The drive to increase the output of animal product in some sectors of ruminant livestock production has led to greater use of feeds such as cereal grains and soyabean meal that are potentially human-edible. This trend has caused concern since, by so doing, ruminants compete not only with monogastric livestock but also with the human population for a limited global area of cultivatable land on which to produce grain crops. Reasons for using potentially human-edible feeds in ruminant diets include increased total daily energy intake, greater supply of essential amino acids and improved ruminal balance between fermentable energy and degradable protein. Soyabean meal, produced on land that has been in arable cultivation for many years can fulfil a useful role as a supplier of undegraded dietary protein in diets for high-yielding dairy cows. However, in the context of sustaining the production of high-quality foods from livestock to meet the demands of a growing human population, the use of potentially human-edible feed resources by livestock should be restricted to livestock with the highest daily nutrient requirements; that is, potentially human-edible feed inputs should be constrained to meeting requirements for energy and protein and to rectifying imbalances in nutrient supply from pastures and forage crops such as high concentrations of nitrogen (N). There is therefore a role for human-edible feeds in milk production because forage-only systems are associated with relatively low output per head and also low N use efficiency compared with systems with greater reliance on human-edible feeds. Profitability on farm is driven by control of input costs as well as product value and examples are given of low-cost bovine milk and meat production with little or no reliance on potentially human-edible feeds. In beef production, the forage-only systems currently under detailed real-time life-cycle analysis at the North Wyke Farm Platform, can sustain high levels of animal growth at low feed cost. The potential of all-forage diets should be demonstrated for a wide range of ruminant milk and meat production systems. The challenge for the future development of ruminant systems is to ensure that potentially human-edible feeds, or preferably human-inedible by-products if available locally, are used to complement pastures and forage crops strategically rather than replace them.
Feeding dairy cows diets rich in grain often leads to subacute rumen acidosis (SARA), which might affect their responsiveness to immunogenic stimuli such as exogenous lipopolysaccharide (LPS), and can lead to metabolic alterations. The main objective of this study was to investigate if SARA affects the stress and metabolic health responses resulting from an intramammary LPS challenge. Before the intramammary LPS challenge, the SARA cows showed higher blood glucose and a tendency for higher lactate and aspartate aminotransferase as well as a trend toward lower β-hydroxybutyrate (BHBA) and γ-glutamyltransferase compared with control cows. After the LPS challenge, the serum cortisol concentration markedly increased and the calcium concentration decreased both in SARA and control cows. In SARA-LPS cows, however, the lactate concentration increased due to the LPS infusion, whereas it remained unchanged in the control cows. A lower serum BHBA concentration was found in SARA-LPS compared with control-LPS cows. Higher non-esterified fatty acid concentrations were found in control-LPS cows shortly before the LPS challenge compared with SARA cows, challenged or not with LPS, whereas it did not differ from SARA-LPS cows thereafter. In conclusion, the results suggest that intramammary LPS challenge induced stress and lowered calcium concentration in all dairy cows, whereby this challenge showed lower BHBA and higher lactate levels in cows with SARA conditions.
Research has shown both production and health benefits for the use of chicory (Cichorium intybus) within ruminant diets. Despite this, little was known about the effects of this forage, containing differing fatty acid profiles and secondary plant compounds compared with ryegrass, on beef stability, fatty acid composition or sensory properties. An experiment was conducted to investigate whether the inclusion of chicory in the diet of grazing beef steers would alter these three properties in the M. Longissimus muscle when compared with beef steers grazing perennial ryegrass (Lolium perenne). Triplicate 2 ha plots were established with a chicory (cv. Puna II)/perennial ryegrass mix or a perennial ryegrass control. A core group of 36 Belgian Blue – cross steers were used within a 2-year beef finishing experiment (n=6/replicate plot). In the 2nd grazing year, steers were slaughtered as they reached a target fat class of 3. Muscle pH was checked 2 and 48 h post-slaughter. A section of the hindloin joint containing the M. Longissimus lumborum muscle was removed and a 20 mm-thick steak was cut and muscle samples were taken for analysis of vitamin E and fatty acid analysis. The remaining section of the loin was vacuum packed in modified atmosphere packs and subjected to simulated retail display. A section of the conditioned loin was used for sensory analysis. Data on pH, vitamin E concentration and colour stability in a simulated retail display showed there were no effects of including chicory in the diet of grazing beef steers on meat stability. There were also no differences found in the fatty acid composition or the overall eating quality of the steaks from the two treatments. In conclusion, there were no substantive effects of including chicory in the swards of grazing beef cattle on meat stability, fatty acid composition or sensory properties of the M. Longissimus muscle when compared with beef steers grazing ryegrass-only swards.
Dietary interventions are a common practice in the poultry industry to promote optimal performance and health of animals. Here, we aim at assessing the influence of supplementing broiler diets with dry whey powder (DWP) and whey protein concentrate (WPC) on nutrient coefficient of apparent ileal digestibility (CAID) and productive performance. Cecal microbiota composition was also determined using Illumina amplicon sequencing. Dietary treatments were control diet (no supplementation of DWP or WPC), 60-DWP (60 g/kg of DWP), and 80-WPC (80 g/kg of WPC). One-day-old male broilers were randomly assigned to one of three treatments, and housed in floor pens. In Trial 1, 90 1-day-old chicks were allocated to three pens/treatment, with 10 birds/pen, during 21 days for CAID evaluation. Diet 60-DWP increased Ca CAID (P=0.041), while diet 80-WPC improved Ca and P CAID (P<0.001 and 0.002, respectively) when compared with control diet. In Trial 2, 810 one-day-old chicks were allocated to nine pens/treatment, with 30 birds/pen, during 42 days. Feeding chickens with 60-DWP and 80-WPC increased their BW, average daily gain (ADG) and feed intake (FI) during the starter (P<0.001 for all variables) and grower-finisher periods (P<0.001 for BW and FI, and P=0.048 for ADG), and during the entire feeding period (P<0.05), when compared with control diet. Diets 60-DWP and 80-WPC reduced the feed conversion ratio of chickens during the starter period (P<0.001 and 0.003, respectively), while 60-DWP reduced this parameter during the entire feeding period (P=0.048), when compared to control diet. At day 42, cecal microbial communities of chickens that were fed with 60-DWP and 80-WPC differed from those fed with control diet (R=0.776, P=0.008; and R=0.740, P=0.008, respectively). The abundance of Bacteroides fragilis, Bacteroides spp., Escherichia coli/Shigella flexneri and Megamonas furniformis increased when 60-DWP and 80-WPC diets were offered, while the presence of Helicobacter pullorum decreased. Lactobacillus salivarius consistently increased in chickens with better feed conversion ratio, which were those fed with 60-DWP. The results obtained in the present study indicate that growth of chickens is improved by DWP and WPC supplementation because of a higher mineral digestibility, increased feed intake and modulation of cecal microbiota communities.
(−)-Hydroxycitric acid (HCA), a major component of Garcinia cambogia extracts, has been shown to suppress BW gain and fat accumulation in animals and humans. However, the mechanism remains unknown. In this study, gas chromatography-mass spectrometry was used to analyse serum metabolites, and principal component analysis and partial least-squares-discriminant analysis models were generated to analyse serum metabolite changes in broiler chickens after the administration of (−)-HCA at 0, 1000, 2000 and 3000 mg/kg diets for 28 days. Metabolites showing significant changes were screened by ‘variable importance in the projection’ plots. The results showed that 20 metabolites in the 1000 mg/kg (−)-HCA treatment group and 16 metabolites in 3000 mg/kg (−)-HCA treatment group were significantly altered. Metabolites pathway enrichment analysis indicated that these metabolites were mainly associated with metabolism of amino acids, protein synthesis, citric acid cycle, and uric acid and fatty acid synthesis. The data indicated that (−)-HCA promoted protein synthesis by regulating the metabolic directions of amino acids. At the same time, (−)-HCA treatment inhibited fatty acid synthesis by promoting the citric acid cycle, resulting in reduced cytosolic acetyl-CoA content in broiler chickens. The present study identified global changes in metabolites and analysed the main canonical metabolic pathways in broiler chickens supplemented with (−)-HCA. These results will deepen our understanding of the mechanism of (−)-HCA’s effects in animals.
Piglet mortality is a major problem in organic pig production affecting both farm economy and animal welfare. Knowledge is scarce on the risk factors of piglet mortality in Danish commercial organic pig production. The objectives of this study were to evaluate season, litter size, parity, sow body condition and stillborn littermates as risk factors for early piglet mortality and crushing of liveborn piglets from parturition until castration at day 3 to 5 postpartum (pp). The study was conducted over a 1-year period in nine commercial Danish organic pig herds practicing outdoor farrowing all year round. Data included recordings on 3393 farrowings with 50 284 liveborn piglets of which 14.8% died before castration. A subset of the dead piglets were collected and necropsied to identify crushed piglets. The average number of liveborn piglets per litter was 14.8 (SD=3.7) and the average time from parturition until castration was 4.1 (SD=1.7) days. A negative binomial regression analysis was used to model the effect of the predictive variables on the early piglet mortality accounting for different time periods from parturition to castration. An increase in maternal body condition score (BCS) and parity significantly increased the risk of dying between parturition and castration. Early mortality was found to be lowest during spring (March to May) and highest during summer (June to August). Being born into a litter with one or more stillborn littermates increased the risk of early mortality. The risk factors for crushing of piglets were evaluated using a logistic analysis. A significant effect of parity and litter size was found where the odds of at least one piglet in a litter with mortality was diagnosed as crushed increased with increasing parity and litter size. In conclusion, being born during summer (June to August), high parity and maternal BCS and stillborn littermates were found to be risk factors for piglet mortality between parturition and castration. In addition, parity and increasing litter size were found to be risk factors for crushing of piglets in litters with mortality.
The objective of this study was to investigate the effects of extruded full-fat soybean (ESB) as a replacement for soybean meal (SBM) on nutrient intake, rumen fermentation, and growth performance of dairy calves. A total of 45 male Holstein dairy calves (42.0±0.5 kg of BW) were randomly assigned to one of three experimental diets: (1) 0% ESB (Control): 35.3% SBM no ESB; (2) 25% ESB: 27.0% SBM+9.0% ESB; and (3) 50% ESB: 19.0% SBM+19.0% ESB. All calves were weaned on day 56 of age and remained in the study until day 70 of age. During the pre-weaning and overall periods, substituting of SBM with ESB had no effect on intake of starter feed, metabolizable energy (ME), CP and non-fiber carbohydrate (NFC). Compared with the control, 50% ESB resulted in a decrease in starter feed intake, and intakes of other nutrients including CP, NFC and ME during the post-weaning period. Substituting SBM with ESB decreased intake of C16 : 0 and increased intakes of n-9 C18 : 1, n-6 C18 : 2 and n-3 C18 : 3 during the pre-weaning, post-weaning and overall periods. Using ESB as a replacement for SBM did not affect average daily gain, feed efficiency, rectal temperature and fecal score over the trial periods. Compared with control, the rumen concentration of NH3-N decreased for 50% ESB on days 35 and 56 of age but not when compared with 25% ESB. Rumen pH, total volatile fatty acids concentrations, and the molar proportions of ruminal acetate, propionate and butyrate were not different among treatments. Body measurements were not affected by the treatments. In conclusion, substitution of SBM with ESB may improve nitrogen utilization efficiency in dairy calves but slightly reduce post-weaning starter intake with no negative outcomes on growth performance and rumen fermentation.
Production diseases in dairy cows are multifactorial, which means they emerge from complex interactions between many different farm variables. Variables with a large impact on production diseases can be identified for groups of farms using statistical models, but these methods cannot be used to identify highly influential variables in individual farms. This, however, is necessary for herd health planning, because farm conditions and associated health problems vary largely between farms. The aim of this study was to rank variables according to their anticipated effect on production diseases on the farm level by applying a graph-based impact analysis on 192 European organic dairy farms. Direct impacts between 13 pre-defined variables were estimated for each farm during a round-table discussion attended by practitioners, that is farmer, veterinarian and herd advisor. Indirect impacts were elaborated through graph analysis taking into account impact strengths. Across farms, factors supposedly exerting the most influence on production diseases were ‘feeding’, ‘hygiene’ and ‘treatment’ (direct impacts), as well as ‘knowledge and skills’ and ‘herd health monitoring’ (indirect impacts). Factors strongly influenced by production diseases were ‘milk performance’, ‘financial resources’ and ‘labour capacity’ (directly and indirectly). Ranking of variables on the farm level revealed considerable differences between farms in terms of their most influential and most influenced farm factors. Consequently, very different strategies may be required to reduce production diseases in these farms. The method is based on perceptions and estimations and thus prone to errors. From our point of view, however, this weakness is clearly outweighed by the ability to assess and to analyse farm-specific relationships and thus to complement general knowledge with contextual knowledge. Therefore, we conclude that graph-based impact analysis represents a promising decision support tool for herd health planning. The next steps include testing the method using more specific and problem-oriented variables as well as evaluating its effectiveness.
Pastoralists have traditional ecological knowledge (TEK), which is important for their livelihoods and for policies and interventions. Pastoralism is under pressure, however, which may result in a decline of pastoral lifestyle and its related TEK. We, therefore, addressed the following objectives (i) to inventorise and assess how pastoralists characterise and value soils and forages in their environment, (ii) to analyse how soil, forage and livestock (i.e. cattle) characteristics relate to herding decisions and (iii) to determine whether TEK underlying herding decisions differs across generations. Data were collected through focus groups and individual interviews with 72 pastoralists, belonging to three generations and to three agro-ecological zones. Using a three-point scale (high, medium, low), four grasses and three tree forages were assessed in terms of nutritional quality for milk, meat, health and strength. Using their own visual criteria, pastoralists identified five different soils, which they selected for herding at different times of the year. Pastoralists stated that Pokuri was the best soil because of its low moisture content, whereas Karaal was the worst because forage hardly grows on it. They stated that perennials, such as Andropogon gayanus and Loxoderra ledermannii, were of high nutritional quality, whereas annuals such as Andropogon pseudapricus and Hyparrhenia involucrata were of low nutritional quality. Afzelia africana was perceived of high quality for milk production, whereas Khaya senegalensis had the highest quality for meat, health and strength. Pastoralists first used soil, then forage and finally livestock characteristics in their herding decisions. Pastoralists’ TEK was not associated with their generations, but with their agro-ecological zones. This study suggests that pastoralists had common and detailed TEK about soils, forages and livestock characteristics, underlying their herding decisions. To conclude, pastoralists use a holistic approach, combining soil, vegetation and livestock TEK in herding decisions. Such TEK can guide restoration or improvement of grazing lands, and land use planning.
Effective tools for male contraception are important in the control of reproduction in animal populations. The aim of the present study was to evaluate the effects of active immunization against gonadotropin-releasing hormone (GnRH) on male reproductive function assessing testicular morphological changes and serum-gonadotropin levels in pre-pubertal rabbits, guinea pigs and ram lambs. An anti-GnRH vaccine was developed by linking a GnRH-homologous molecule to a tetanus clostridial toxoid (Al(OH)3 coadjuvant). After vaccination protocols testicular morphometry, histopathological alterations and endocrine responses (FSH, LH, testosterone and cortisol serum levels) were evaluated. Testicular volume was significantly reduced in vaccinated animals with respect to the control group in rabbits, guinea pigs and ram lambs (P<0.05 to P<0.001). The anti-GnRH vaccine generated a reduction in testicular volume of 15-, 27- and 11-fold, respectively. Tubule diameters decreased in the vaccinated group with respect to the control ~2.0-, 1.2- and 3.5-fold, respectively (P<0.001). Tubule, intertubular and lumen volumes significantly decreased in vaccinated rabbits (P<0.05), guinea pigs and ram lambs (P<0.01). Vaccinated animals of the three species showed significant reductions in spermatogonial numbers (10- to 40-fold; P<0.01). Sperm was absent in all seminiferous tubules of all rabbits, and most individuals of guinea pigs (80%) and ram lambs (60%). No significant differences were observed between vaccinated and control groups regarding FSH and LH during the experiments in the three experimental species/models used. Testosterone, however, was only significantly lower (~22-fold, P<0.01) in vaccinated rabbits. In conclusion, the present study demonstrated that pre-pubertal active immunization against GnRH leads to endocrine disruption and marked differences on testicular morphometry, development and activity among lagomorphs, hystricomorphs and ovine species with species-specific sensitivity regarding the anti-GnRH immune response.
Feeding dried distillers grains with solubles (DDGS), a feed high in fat and protein, to lactating beef cows can alter milk production and composition, resulting in improved pre-weaning growth of progeny. This alteration in milk profile may consequently alter the growth and carcass composition of the offspring after weaning. Therefore, Angus×Simmental steers (n=48) whose dams were fed one of two diets supplemented with either DDGS or soybean meal (CON) from calving to mid-lactation were placed in a feedlot to determine the effects of maternal nutrition during lactation on progeny development and carcass composition. Cow–calf pairs were allotted to two treatments at birth based on cow and calf BW, breed and age. Maternal diets were isocaloric (3.97 MJ/kg NEg) and consisted of rye hay supplemented with DDGS at 1% of BW (19.4% CP; 8.76% fat) or rye hay and corn silage supplemented with CON (11.7% CP; 2.06% fat). After conclusion of the treatments at 129 days postpartum, cow–calf pairs were comingled and managed as one group until weaning at 219 days postpartum. Steers were then transitioned to a common diet composed of 60% DDGS, 34% corn silage and 6% vitamin/mineral supplement and were placed indoors in individual pens with slatted floors. An intravenous glucose tolerance test (IVGTT) was performed 134 days after feedlot entry on 16 steers (CON, n=7; DDGS, n=9) to determine the effect of maternal diet on glucose and insulin sensitivity. Steers were slaughtered at a target BW of 645 kg. Categorical and continuous data were analyzed using the GLIMMIX and MIXED procedures of SAS, respectively. Steers from DDGS dams tended to be heavier on day 85 of feedlot finishing (P=0.09) compared with steers from CON dams. However, there were no differences in final weight, average daily gain, dry matter intake or efficiency (gain:feed, P⩾0.18). Maternal treatments did not affect progeny days on feed (P=0.15), despite a mean difference of 9 days in favor of DDGS. Glucose and insulin concentrations and area under the curve of progeny as measured by IVGTT were not affected by maternal diet (P⩾0.16). Maternal DDGS supplementation decreased marbling score (P=0.04), but did not influence carcass grading percentage or any other carcass characteristic (P⩾0.17).