Immunity-related traits are heritable in chicken, therefore, it is possible to improve the inherent immunity by breeding programs. In this study using the Illumina chicken 60K single nucleotide polymorphisms (SNPs) chip, we performed a set of genome-wide association studies to determine candidate genes and loci responsible for primary and secondary antibody-mediated responses against sheep red blood cell. A F2 population descended from a commercial meat-type breed and an Iranian indigenous chicken was used for this study. Statistical analysis was based on a mixed linear model utilizing genomic relationship matrix to prevent spurious associations. Correction for multiple testing was done by applying 5% and 10% chromosomal false discovery rates (FDRs) for significant and suggestive thresholds, respectively. Nine significant and 17 suggestive associated SNPs were identified. Most of the SNPs that were suggestively associated with the primary response of total plasma immunoglobulins were also significantly associated with this trait in secondary response. Three SNPs were located within a narrow region of 23 kb on chromosome 16. Pathway analysis for the genes surrounding the associated SNPs showed that they are involve in antigen processing and presentation, primary immunodeficiency, vitamin digestion and absorption, cell adhesion molecules, phagosome, influenza A, folding, assembly and peptide loading of class I major histocompatibility complex, lipid digestion, mobilization, and transport (FDR < 0.1). Interestingly, there were common regains associated with multiple immune-related traits.

Longevity is one of the most important traits determining dairy cow profitability. In the last decades dairy cows suffered a lowering in the age at culling. With the aim to identify the genes involved in longevity, dates of birth, yields, dates of calving during lifespan and culling dates were collected for 946 culled cows which had been genotyped with the Bovine High Density panel. Using the GenABEL package in R, genome-wide association analysis was performed on three potential traits of longevity: (1) ‘days in production,’ (2) ‘days in herd,’ (3) number of calvings over lifespan.’ Five genome-wide significant single nucleotide polymorphisms (SNPs) associated with all three longevity traits were detected. Several consecutive SNPs identified on chromosomes 16 and 30 indicated the presence of two suggestive quantitative trait loci (QTL). The genes comprised in the QTL regions had biological functions related to fertility, reproductive disorders, heat stress and welfare of cows. These findings might contribute to improving breeding strategies to improve longevity.

The alpaca fiber diameter (FD) varies from 18 to 36 μm, being the finer fiber categories highly appreciated. However, the alpaca fiber presents some limitations in the textile industry due to the high incidence of fiber medullation and diameter variability, both reduces the comfort feeling of the garments. Decreasing or even removing medullation could be a possible selection objective in alpaca breeding programs for increasing economic value of the alpaca fiber. Therefore, the present work aimed to estimate genetic parameters regarding medullation traits, as well as the genetic correlations with other economical important traits, to be able to select the appropriate criteria to reduce or remove medullation on alpaca fiber and help to reduce the prickle factor in the garments. The data was collected from 2000 to 2017 and belonged to the Pacomarca experimental farm. There were 3698 medullation records corresponding to 1869 Huacaya and 414 Suri genetic types. The fiber samples were taken from the mid side, and were analyzed in an OFDA 100® device. The traits analyzed were percentage of medullation (PM), medullated fiber diameter (MFD), FD, standard deviation of FD, greasy fleece weight as fiber traits; density, crimp in Huacaya and lock structure in Suri, head conformation, leg coverage as morphological traits; weaning weight and age at first calving as secondary and functional traits. Genetic parameters were estimated via a multitrait restricted maximum likelihood. The heritabilities for PM and MFD were 0.225 and 0.237 in Huacaya genetic type and 0.664 and 0.237 in Suri genetic type, respectively; heritabilities for other traits were moderate for productive and morphological traits, and low to moderate for secondary and functional traits. The genetic correlations PM–FD and MFD–FD were high and favorable in both genetic types, between 0.531 and 0.975; the genetic correlation PM–MFD was 0.121 in Huacaya and 0.427 in Suri. The rest of genetic correlations with other traits were in general moderate and favorable. The repeatabilities were 0.556 and 0.668 for PM, and 0.322 and 0.293 for MFD in Huacaya and Suri genetic types, respectively. As a conclusion, PM was identified to be a good selection criterion, probably combined in an index with FD to reduce prickling factor.

The increasing global need to find alternative protein/energy sources has triggered research in the field of non-conventional feed ingredients, with insects and former foodstuffs being the most promising. Insects contain high level of protein and fat, whereas former foodstuffs contain high energy in the form of carbohydrates and fats; therefore, both should be considered as promising alternative feed ingredients for livestock production. In addition to the nutritional value, they also represent a way by which food waste biomasses/streams can be upgraded to valuable feed ingredients. This review outlines the main nutritional and safety issues of insects and former foodstuffs, and also considers the legal framework involved. The importance of the type of insect metamorphosis and tailored substrates that could lead to the production of a premium feed is also described. This is also the first time that a review discusses the nutritional quality of former foodstuffs. Energy and the main nutrient content of former foodstuff are compared with the composition of common cereals as the principal energy sources in animal feed. For both ingredients a critical review of the safety issues is provided. Based on the current data available, both insects and former foodstuffs have an excellent potential use as alternative feed ingredients for livestock production. When produced in line with the criteria set by major feed/food authorities, they are characterized by high quality and safety standards. This makes them comparable to other feed materials and ingredients currently available on the market, although their full nutritional, functional, safety and sustainability evaluation cannot be considered complete.

Protein is the most costly nutrient in fish feed, and while diets offered in the early stages of development typically have high levels of CP, they do not always correspond to the real requirements of the animals. Thus, research that seeks to learn the true nutritional requirements of fish is fundamental to improving commercial fish culture. The present study evaluated the protein requirements of Nile tilapia (Oreochromis niloticus) under larviculture. Fish performance, gene expression for digestive enzymes and their enzymatic activity and stress response to air exposure were analyzed. Four experimental diets differing in CP level were formulated: 30%, 36%, 42% and 48%. Fish larvae were fed the experimental diets during development and sampled 10, 20 and 30 days after the beginning of the experiment for performance, gene expression and enzymatic activity. At sampling time 30, stress resistance was also evaluated by means of an air exposure test. At sampling time 10, CP levels between 36% and 48% could be used for a better performance. During this period, pepsinogen expression was greater for 30% CP, intermediate for 42% and lower for 36% and 48%. After this initial period, diets of between 30% and 42% CP are recommended for better performance. At sampling time 20, gene expression for digestive enzymes and their enzymatic activity were similar for all diets tested. At sampling time 30, the diet of 42% CP induced both greater pepsinogen expression and pepsin activity. Survival after the air exposure test after 30 days of feeding was influenced by CP level in the diet, with the highest survival being for fish fed with 36% CP. Taken together, the present results demonstrate that dietary CP influences digestive enzyme gene expression and activity, and suggest that the best CP levels for Nile tilapia larviculture vary depending on larval stage.

Optimizing feeding regimens in early life to maximize lifelong growth and production are essential in the dairy industry. This study investigated the effects of milk replacer (MR) feeding frequency and calf age on behavior, and glucose and insulin kinetics of pre- and post-weaned calves fed an elevated plane of MR. Ten male Holstein calves (42.2±1.8 kg BW) were blocked by BW and randomly assigned to two treatments offering 8 l MR/day (150 g/l) in two (2×; meal size 4 l) or four (4×; meal size 2 l) feedings via an automated calf feeder. Milk replacer was gradually stepped down by 1 l/day during week 8, with calves being weaned by week 9. Water and pelleted calf starter were offered ad libitum. Individual intake of MR and starter were recorded daily, and BW was recorded weekly. The number of visits to the MR feeder (rewarded and unrewarded), and behaviors such as lying, cross-sucking, non-nutritive sucking and occupancy time in the feeder were recorded for individual calves from weeks 4 to 10. Jugular catheters were placed on weeks 4, 7 and 10 to facilitate postprandial blood sampling and glucose tolerance tests. Statistical analysis was conducted using the PROC GLIMMIX procedure (SAS) for behavioral observations, and the MIXED procedure (SAS) with repeated measures for BW, intake, plasma glucose and plasma insulin data. Final BW, starter and MR intake did not differ between treatments. There were no differences in observed calf behaviors; with the exception that 2× calves visited the MR feeder more often (P<0.01; total: unrewarded and rewarded). Baseline concentrations (mmol/l) and the maximum change in glucose (delta, mmol/l) were greater and lower (P=0.02) in 4×compared to 2×calves, respectively. Postprandial insulin AUC240 tended (P=0.09) to be greater in 2×calves, compared to 4×calves at week 7. Similarly, Tmax (min), AUC240 and delta values (µU/ml) were greater (P⩽0.05) in 2×calves, compared to 4×calves. No treatment ×age interactions were observed for glucose or insulin during the glucose tolerance tests. Therefore, we conclude that feeding an elevated plane of MR (8 l/day) at a lower frequency (2× v. 4×) increased feeder visits, but not other hunger-related behaviors, and while postprandial glucose and insulin parameters varied, insulin sensitivity remained stable in Holstein dairy calves up to 10 weeks of age in calves consuming similar levels of calf starter.

Sufficient amino acid (AA) transport is essential to ensure the normal physiological function and growth of growing animals. The processes of AA sensing and transport in humans and murine animals, but rarely in goats, have been arousing great interest recently. This study was conducted to investigate the messenger RNA expression patterns of lysophosphatidic acid receptor 5 (LPAR5), guanine nucleotide-binding protein α-transducing 3 (GNAT3) and important partial AA transporters in digestive tracts, metabolic organs and muscles of growing goats. The results showed that these genes were widely expressed in goats, and had different expression patterns. LPAR5, GNAT3, solute carrier (SLC38A2), SLC7A7, SLC7A1 and SLC3A1 were rarely expressed in the rumen, but were highly expressed in the abomasum and intestine which are the main sites of AA absorption. GNAT3, SLC38A1, SLC38A2, SLC6A19, SLC7A7 and SLC7A1 showed comparatively high expression in the pancreas and the vital digestive glands, and the relatively high expression of these nine genes were noted in the tibialis posterior, the active muscle in energy metabolism. The correlation analysis showed that there were certain positive correlation among most genes. The current results indicate that the AA sensing and transport occur extensively in the abomasum and small intestine, metabolic organs and muscle tissues of ruminants, and that related genes have tissue specificity.

The protein nutrition of dairy cows is of great importance because of its direct influence on milk production, reproductive efficiency, and feeding cost. Eight first-lactation Holstein cows were randomly assigned to two contemporary 4 × 4 Latin squares in a 2 × 2 factorial design to evaluate the effects of replacing soybean meal with yeast-derived microbial protein (YMP) as a protein source (0% or 1.5% of dry matter (DM)) and its combination with slow-release urea (SRU; 0% or 0.75% of DM) on DM intake and milk production and composition, as well as blood parameters and nitrogen balance. Each experimental period lasted 28 days, with 21 days of adaptation and 7 days of data collection. The diets were formulated to attend the nutritional recommendations of the National Research Council and consisted of 49% forage (47% corn silage and 2% Tifton hay) and 51% concentrate, with 16.8% CP and 1.6 Mcal net energy for lactation/kg DM. For diets without YMP, the inclusion of SRU decreased DM intake, milk production as well as N intake and balance, but did not affect efficiency of production, milk composition or most of blood parameters. On the contrary, for diets with YMP, DM intake and milk production were increased by inclusion of SRU, while minor effects were observed for milk efficiency and composition, blood parameters as well as N intake, excretion and balance. When diets with SRU were compared, the inclusion of YMP increased DM intake, 4% fat-corrected milk, and N intake and balance (P<0.05), with no differences in milk production (kg/day), milk energy, efficiency of milk production or most of the blood parameters. For diets without SRU, YMP inclusion decreased DM intake, milk production, milk energy, N intake, fecal N and N balance (P<0.05), with no effects on milk efficiency and composition, or most of blood parameters. In conclusion, the use of YMP, SRU or both as partial substitutes of soybean meal in the diet of lactating cows has no negative effects on productivity parameters.

The potassium sensitive magnesium absorption through the rumen wall may be influenced by additional dietary properties, such as diet type, forage type or forage to concentrate ratio. These properties are likely associated to rumen passage kinetics modified by dietary fibre content. The study aimed to assess the effects of rumen passage kinetics on apparent Mg absorption and retention in lactating dairy cows fed modified levels of fibre. Six lactating Red-Holstein and Holstein cows, including four fitted with ruminal cannulas were randomly assigned to a 3 × 3 cross-over design. The experimental diets consisted of early harvested low NDF (341 g NDF/kg DM) and late harvested high NDF (572 g NDF/kg DM) grass silage (80% DM) and of concentrates (20% of DM). As the low-fibre diet was excessive in protein, a third high-fibre diet was formulated to be balanced in digestible protein with the low-fibre diet to avoid any eventual confounding effects of NDF and protein excess. All diets were formulated to contain iso-Ca, -P, -Mg, -K and -Na. Passage kinetics of solid and liquid phase of rumen digesta were evaluated using ruminal marker disappearance profiles. Cows fed the low-fibre diet had compared to the other diets, an up to 40% lower solid and 26% lower liquid phase volume of rumen digesta and a 10% numerically higher fractional rumen liquid passage rate. Rumen pH lost 0.6 units and Mg concentration in the rumen liquid phase tripled when cows were fed the low-fibre diet. Faecal Mg excretion was up to 14% higher in cows fed the low-fibre diet and Mg absorbability was 12% compared to up to 19% in other diets. Urinary Mg excretion in cows fed the low-fibre diet was half of the ones in the other treatments, but Mg retention was not affected. Dietary protein excess neither affected rumen passage kinetics nor Mg absorption and retention. Absorption of Mg was correlated with rumen liquid volume which both decreased with decreasing daily NDF intake (NDFi, 11.8 ± 2.4 l/kg NDFi). Consequently, daily Mg absorption decreased by 1.32 ± 0.28 g/kg decreasing NDFi. To conclude, in addition to the known antagonistic effect of dietary K, the present data indicate that Mg absorption was dependent from NDFi which modified rumen liquid volume, but was independent of dietary protein excess likely associated to low NDF herbages.

Optimizing milk production efficiency implies diets allowing low methane (CH4) emissions and high dairy performance. We hypothesize that nature of energy (starch v. lipids) and lipid supplement types (monounsaturated fatty acid (MUFA) v. polyunsaturated fatty acid (PUFA) mitigate CH4 emissions and can induce low milk fat content via different pathways. The main objective of this experiment was to study the effects of starch-rich or lipid-supplemented diets that induce milk fat depression (MFD) on rumen biohydrogenation (RBH) of unsaturated fatty acids (FA) and enteric CH4 emissions in dairy cows. Four multiparous lactating Holstein cows (days in milk=61±11 days) were used in a 4×4 Latin square design with four periods of 28 days. Four dietary treatments, three of which are likely to induce MFD, were based (dry matter basis) on 56% maize silage, 4% hay and 40% concentrates rich in: (1) saturated fatty acid (SFA) from Ca salts of palm oil (PALM); (2) starch from maize grain and wheat (MFD-Starch); (3) MUFA (cis-9 C18:1) from extruded rapeseeds (MFD-RS); and (4) PUFA (C18:2n-6) from extruded sunflower seeds (MFD-SF). Intake and milk production were measured daily. Milk composition and FA profile, CH4 emissions and total-tract digestibility were measured simultaneously when animals were in open-circuit respiration chambers. Fermentation parameters were analysed from rumen fluid samples taken before feeding. Dry matter intake, milk production, fat and protein contents, and CH4 emissions were similar among the four diets. We observed a higher milk SFA concentration with PALM and MFD-Starch, and lower milk MUFA and trans-10 C18:1 concentrations in comparison to MFD-RS and MFD-SF diets, while trans-11 C18:1 remained unchanged among diets. Milk total trans FA concentration was greater for MFD-SF than for PALM and MFD-Starch, with the value for MFD-RS being intermediate. Milk C18:3n-3 content was higher for MFD-RS than MFD-SF. The MFD seems more severe with MFD-SF and MFD-RS than PALM and MFD-Starch diets, because of a decrease in milk SFA concentration and a stronger shift from trans-11 C18:1 to trans-10 C18:1 in milk. The MFD-SF diet increased milk trans FA (+60%), trans-10 C18:1 (+31%), trans-10,cis-12 CLA (+27%) and PUFA (+36%) concentrations more than MFD-RS, which explains the numerically lowest milk fat yield and indicates that RBH pathways of PUFA differ between these two diets. Maize silage-based diets rich in starch or different unsaturated FA induced MFD with changes in milk FA profiles, but did not modify CH4 emissions.

In pig husbandry, pregnant females are often exposed to stressful conditions, and their outcomes on maternal and offspring health have not been well evaluated. The present study aimed at testing whether improving the welfare of gestating sows could be associated with a better maternal health during gestation, changes in the composition of lacteal secretions and improvement in piglet survival. Two contrasted group-housing systems for gestating sows were used, that is, a French conventional system on slatted floor (C, 49 sows) and an enriched system using larger pens on deep straw (E, 57 sows). On the 105th days of gestation (DG105), sows were transferred into identical farrowing crates on slatted floor. Saliva was collected from all sows on DG35, DG105 and DG107. Blood samples were collected on DG105 from all sows and on the 1st day of lactation (DL1) from a subset of them (C, n=18; E, n=19). Colostrum and milk samples were collected from this subset of sows at farrowing (DL0) and DL4. Saliva concentration of cortisol was greater in C than in E sows at DG35 and DG105, and dropped to concentrations comparable to E sows after transfer into farrowing crates (DG107). On DG105, plasma concentrations of haptoglobin, immunoglobulins G (IgG) and A (IgA), blood lymphocyte counts and plasma antioxidant potential did not differ between groups (P > 0.10), whereas blood granulocyte count, and plasma hydroperoxide concentration were lower in E than in C sows (P < 0.05). Concentrations of IgG and IgA in colostrum and milk did not differ between the two groups. The number of cells did not differ in colostrum but was greater in milk from E than C sows (P < 0.05). Pre-weaning mortality rates were lower in E than C piglets (16.7% v. 25.8%, P < 0.001), and especially between 12 and 72 h postpartum (P < 0.001). Plasma concentration of IgG was similar in E and C piglets on DL4. In conclusion, differences in salivary cortisol, blood granulocyte count and oxidative stress markers between groups suggested improved welfare and reduced immune solicitation during late gestation in sows of the E compared with the C system. However, the better survival observed for neonates in the E environment could not be explained by variations in colostrum composition.

Sow environment during gestation can generate maternal stress which could alter foetal development. The effects of two group-housing systems for gestating sows on piglet morphological and physiological traits at birth were investigated. During gestation, sows were reared in a conventional system on a slatted floor (C, 18 sows), demonstrated as being stressful for sows or in an enriched system in larger pens and on deep straw bedding (E, 19 sows). On gestation day 105, sows were transferred into identical individual farrowing crates on a slatted floor. Farrowing was supervised to allow sampling from piglets at birth. In each litter, one male piglet of average birth weight was euthanized immediately after birth to study organ development and tissue traits. Blood samples were collected from 6 or 7 piglets per litter at birth and 2 piglets per litter at 4 days of lactation (DL4). At birth, mean piglet BW did not differ between groups (P > 0.10); however, the percentage of light (<1.2 kg) and heavy (⩾2 kg) piglets was greater and lower, respectively, in C than in E litters (P < 0.01). Plasma concentrations of cortisol, IGF-I, T4, T3, lactate, NEFA, fructose and albumin did not differ (P > 0.10) between C and E piglets, but the insulin to glucose ratio was greater (P = 0.02) in C than in E piglets. Compared with E piglets, C piglets had a lighter gut at birth (P = 0.01) and their glycogen content in longissimus muscle was lower (P < 0.01). In this muscle, messenger RNA levels of PAX7, a marker of satellite cells and of PPARGC1A, a transcriptional coactivator involved in mitochondriogenesis and mitochondrial energy metabolism, were greater (P < 0.05), whereas the expression level of PRDX6, a gene playing a role in antioxidant pathway, was lower (P = 0.03) in C than in E piglets. Other studied genes involved in myogenesis did not differ between C and E piglets. No system effect was observed on target genes in liver and subcutaneous adipose tissue. On DL4, C piglets exhibited a lower plasma antioxidant capacity than E piglets (P = 0.002). In conclusion, exposure of sows to a stressful environment during gestation had mild negative effects on the maturity of piglets at birth.

Distillers dried grains with solubles (DDGS) are highly susceptible to lipid oxidation because DDGS contain about 10% crude fat, which is largely composed of polyunsaturated fatty acids. l-carnitine serves an important function in fatty acids β-oxidation, and also has antioxidant properties. The objective of this study was to examine the effects of l-carnitine in the DDGS diet of gestating and lactating sows on reproductive performance, milk composition and antioxidant status of sows and their offspring. One hundred and twenty sows (Landrace×Large white, mean parity 4.2, initial BW 230 kg) were randomly allotted to 1 of 4 dietary treatments (n=30 sows/treatment). Treatments were arranged as a 2×2 factorial with two levels of dietary DDGS (0 v. 250 g/kg in gestating diets and 400 g/kg in lactating diets) and two levels of dietary l-carnitine (0 v. 100 mg/kg in gestating diets and 0 v. 200 mg/kg in lactating diets). Distillers dried grains with solubles had no significant effect on litter size but significantly reduced the birth weights and weaning weights of piglets (P<0.05). Distillers dried grains with solubles reduced the antioxidant enzyme activities (P<0.05) and increased the malondialdehyde level in the plasma of sows on day 60 of gestation (P=0.004) and day 14 of lactation (P=0.008). The compositions of colostrum and milk were not affected by inclusion of DDGS and dietary l-carnitine (P>0.05). Supplementing the diets with l-carnitine had no significant effect of total litter size (P>0.05) but increased the number of piglets born alive and piglets weaned, birth weight and weaning weight of piglets and litter weight at birth and weaning (P<0.05). l-carnitine supplementation also increased the concentration of l-carnitine in milk and l-carnitine status of piglets (P<0.05). The antioxidant enzyme activities of new born and weaning piglets were increased (P<0.05) by maternal dietary l-carnitine but this did not extend to finishing pigs. In conclusion, including DDGS in the sows diet could induce oxidative stress, which may be associated with the reduced individual birth and weaning weight of piglets. Dietary l-carnitine supplementation improved the antioxidant and l-carnitine status of sows, which may be associated with the improved reproduction and piglet performance and the antioxidant status of piglets at birth and weaning. There were no interactions between DDGS and l-carnitine.

The aim of this study was to examine the metabolic response to feed deprivation up to 48 h in low and high yielding lamb genotypes. It was hypothesised that Terminal sired lambs would have decreased plasma glucose and increased plasma non-esterified fatty acids (NEFA) and β-hydroxybutyrate (BHOB) concentrations in response to feed deprivation compared to Merino sired lambs. In addition, it was hypothesised that the metabolic changes due to feed deprivation would also be greater in progeny of sires with breeding values for greater growth, muscling and leanness. Eighty nine lambs (45 ewes, 44 wethers) from Merino dams with Merino or Terminal sires with a range in Australian Sheep Breeding Values (ASBVs) for post-weaning weight (PWT), post-weaning eye muscle depth and post-weaning fat depth (PFAT) were used in this experiment. Blood samples were collected via jugular cannulas every 6 h from time 0 to 48 h of feed deprivation for the determination of plasma glucose, NEFA, BHOB and lactate concentration. From 12 to 48 h of feed deprivation plasma glucose concentration decreased (P < 0.05) by 25% from 4.04 ± 0.032 mmol/l to 3.04 ± 0.032 mmol/l. From 6 h NEFA concentration increased (P < 0.05) from 0.15 ± 0.021 mmol/l by almost 10-fold to 1.34 ± 0.021 mmol/l at 48 h of feed deprivation. Feed deprivation also influenced BHOB concentrations and from 12 to 48 h it increased (P < 0.05) from 0.15 ± 0.010 mmol/l to 0.52 ± 0.010 mmol/l. Merino sired lambs had a 8% greater reduction in glucose and 29% and 10% higher NEFA and BHOB response, respectively, compared to Terminal sired lambs (P < 0.05). In Merino sired lambs, increasing PWT was also associated with an increase in glucose and decline in NEFA and BHOB concentration (P < 0.05). In Terminal sired lambs, increasing PFAT was associated with an increase in glucose and decline in NEFA concentration (P < 0.05). Contrary to the hypothesis, Merino sired lambs showed the greatest metabolic response to fasting especially in regards to fat metabolism.

Under current Australian industry pre-slaughter guidelines, lambs may be off feed for up to 48 h before slaughter. The purpose of this study was to examine what proportion of circulating metabolites at slaughter are due to stress and feed deprivation and if this response differs between Merino and Terminal genotypes. In addition the effect of feed deprivation on carcass weight and meat quality was examined. Jugular blood samples were collected from 88 Merino and Terminal sired lambs at rest and at slaughter following 24, 36 and 48 h of feed deprivation and plasma analysed for glucose, lactate, non-esterified fatty acids (NEFA) and β-hydroxybutyrate (BHOB). From the same carcasses hot carcass weight (HCWT) were measured as well as a suite of meat quality traits measured such as M. longissimus lumborum (loin) and M. semitendinosus pH at 24 h postmortem. Loin samples were also analysed for intramuscular fat content and Warner–Bratzer Shear Force. Merino sired lambs had a higher NEFA response compared to Terminal sired lambs at slaughter after 24, 36 and 48 h of feed deprivation, with NEFA levels up to 35% higher than previously reported in the same animals at rest in animal house conditions, whereas BHOB response to feed deprivation was not affected by sire type (P>0.05) and similar to previously reported at rest. In addition to the metabolic effects, increasing feed deprivation from 36 h was associated with a 3% reduction in HCWT and dressing percentage as well as causing increased ultimate pH in the M. semitendinosus in Merino sired lambs. Findings from this study demonstrate that Merino and Terminal sired lambs differ in their metabolic response to feed deprivation under commercial slaughter conditions. In addition, commercial feed deprivation appears to have a negative effect on ultimate pH and carcass weight and warrants further investigation.

Excessive mobilization of body reserves during the transition from pregnancy to lactation imposes a risk for metabolic diseases on dairy cows. We aimed to establish an experimental model for high v. normal mobilization and herein characterized performance, metabolic and endocrine changes from 7 weeks antepartum (a.p.) to 12 weeks postpartum (p.p.). Fifteen weeks a.p., 38 pregnant multiparous Holstein cows were allocated to two groups that were fed differently to reach either high or normal body condition scores (HBCS: 7.2 NEL MJ/kg dry matter (DM); NBCS: 6.8 NEL MJ/kg DM) at dry-off. Allocation was also based on differences in body condition score (BCS) in the previous and the ongoing lactation that was further promoted by feeding to reach the targeted BCS and back fat thickness (BFT) at dry-off (HBCS: >3.75 and >1.4 cm; NBCS: <3.5 and <1.2 cm). Thereafter, both groups were fed identical diets. Blood samples were drawn weekly from 7 weeks a.p. to 12 weeks p.p. to assess the serum concentrations of metabolites and hormones. The HBCS cows had greater BCS, BFT and BW than the NBCS cows throughout the study and lost more than twice as much BFT during the first 7 weeks p.p. compared with NCBS. Milk yield and composition were not different between groups, except that lactose concentrations were greater in NBSC than in HBCS. Feed intake was also greater in NBCS, and NBCS also reached a positive energy balance earlier than HBCS. The greater reduction in body mass in HBCS was accompanied by greater concentrations of non-esterified fatty acids, and β-hydroxybutyrate in serum after calving than in NBCS, indicating increased lipomobilization and ketogenesis. The mean concentrations of insulin across all time-points were greater in HBCS than in NBCS. In both groups, insulin and IGF-1 concentrations were lower p.p than in a.p. Greater free thyroxine (fT4) concentrations and a lower free 3-3′-5-triiodothyronine (fT3)/fT4 ratio were observed in HBCS than in NBCS a.p., whereas p.p. fT3/fT4 ratio followed a reverse pattern. The variables indicative for oxidative status had characteristic time courses; group differences were limited to greater plasma ferric reducing ability values in NBSC. The results demonstrate that the combination of pre-selection according to BCS and differential feeding before dry-off to promote the difference was successful in obtaining cows that differ in the intensity of mobilizing body reserves. The HBCS cows were metabolically challenged due to intense mobilization of body fat, associated with reduced early lactation dry matter intake and compromised antioxidative capacity.

Lower egg shell temperatures (EST) during the first 2 weeks of incubation, notionally known as Slow start incubation, extended the standing time of a 5-week-old fast feathering meat chicken parent line. This study was designed to evaluate the effect of Slow start incubation on the standing ability of commercial meat chickens. Eggs from two strains of meat chickens, Strains 1 and 2, were incubated using either the Slow start incubation, (the initial EST was 36.75°C followed by a gradual increase in EST, reaching 37.8°C at day 16 of incubation), or Control incubation (EST 37.75°C to 38°C from the start of incubation until day 18 of incubation). Eggs were observed every 6 h from 468 h until 516 h of incubation to identify chick hatch window. At 516 h of incubation all chicks were taken out of the incubator (take-off). Chicks from each Strain and incubation treatment were randomly selected for assessment of chick weight, chick length, yolk sac weight, serum Ca and P, and femoral bone ash (BA). All unhatched eggs were inspected to determine the stage of embryo failure. Remaining chicks were grown for 5 weeks in floorpens. Weekly feed intake (FI), chick weight and feed conversion ratio (FCR) were determined. At 35 days of age the standing ability of visibly male birds was assessed in a latency-to-lie test. Compared to the Control, Slow start incubation delayed the average hatch time of both strains by ∼13 h, and reduced hatchability with 4.6% live but unhatched chicks, which was most evident in Strain 2. Significant differences due to main effects only were observed at take-off. Strain 1 chicks were significantly heavier and longer with higher serum Ca but significantly lower BA and serum P than Strain 2. Slow start incubation generated significantly heavier chicks that were shorter, but had significantly heavier yolk sacs, lower serum Ca but higher serum P than Control incubated chicks. During the 1st week post hatch Strain 1 Control incubated chicks had significantly higher FI and higher FCR than all other Strain and incubation treatments. At 35 days of age Slow start incubated birds of both Strains stood significantly longer than those from the Control incubation. This experiment clearly demonstrated the ability of Slow start incubation of commercial meat chickens to improve their leg strength.

Plant secondary metabolites (PSM) are one of the promising options to control gastrointestinal nematodes in sheep and goats. The objective of this study was to assess the abilities of sheep and goats to self-medicate with tannin-rich sainfoin (Onobrychis viciifolia) (SF) when infected with gastrointestinal nematodes, using a cafeteria and an operant conditioning trial. Hypotheses were that parasitized (P) lambs and goat kids would show greater intake and preference for SF than their non-parasitized (NP) counterparts, that kids would eat more SF than lambs (due to their lower resistance against parasites and their greater ability to consume PSM), and that SF intake would increase over time for P animals. We used 20 female kids and 20 ewe lambs aged 3 months. Half of the animals per species (n = 10) were experimentally infected with 170 L3 larvae of Haemonchus contortus/kg of BW (P). The other half were free from parasites throughout the study (NP). Five weeks after infection, animals were exposed to a 24-day cafeteria trial (three 8-day periods) offering a free choice between two legume pellets: SF (3.8% condensed tannins) and alfalfa (ALF, Medicago sativa; no tannin). Subsequently, animals were involved in an operant conditioning trial of two 4-day long sessions, to assess in short-term tests their motivation to walk for a SF reward when offered in choice with freely available ALF. In the cafeteria trial, SF preference was greater in kids than in lambs, particularly in the first two periods. We did not observe a greater preference for SF in P animals, which was even greater in NP animals for periods 1 and 2. Sainfoin intake increased through periods for P animals, which led to similar SF preferences for all groups during period 3. In the operant-conditioning trial, motivation to get the SF reward was similar between P and NP animals. These results support the hypotheses that goats are more willing to consume tanniferous feeds than sheep, and that P animals increased SF intake through time. However, the emergence of a curative self-medicative behaviour was not supported, as P individuals did not show greater SF intake, preference, nor a greater motivation to get SF than NP animals, regardless of animal species. These findings are discussed with previous results and some explanations are presented.

The choice of animal-based traits to identify and deal with production diseases is often a challenge for pig farmers, researchers and other related professionals. This systematic review focused on production diseases, that is, the diseases that arise from management practices, affecting the digestive, locomotory and respiratory system of pigs. The aim was to classify all traits that have been measured and conduct a meta-analysis to quantify the impact of diseases on these traits so that these can be used as indicators for intervention. Data were extracted from 67 peer-reviewed publications selected from 2339 records. Traits were classified as productive (performance and carcass composition), behavioural, biochemical and molecular traits. A meta-analysis based on mixed models was performed on traits assessed more than five times across studies, using the package metafor of the R software. A total of 524 unique traits were recorded 1 to 31 times in a variety of sample material including blood, muscle, articular cartilage, bone or at the level of whole animal. No behavioural traits were recorded from the included experiments. Only 14 traits were measured on more than five occasions across studies. Traits within the biochemical, molecular and productive trait groups were reported most frequently in the published literature and were most affected by production diseases; among these were some cytokines (interleukin (IL) 1-β, IL6, IL8 and tumour necrosis factor-α), acute phase proteins (haptoglobin) and daily weight gain. Quantification of the influence of factors relating to animal characteristics or husbandry practices was not possible, due to the low frequency of reporting throughout the literature. To conclude, this study has permitted a holistic assessment of traits measured in the published literature to study production diseases occurring in various stages of the production cycle of pigs. It shows the lack of consensus and common measurements of traits to characterise production diseases within the scientific literature. Specific traits, most of them relating to performance characteristics or immunological response of pigs, are proposed for further study as potential tools for the prognosis and study of production diseases.

Insight into current scientific applications of Big Data in the precision dairy farming area may help us to understand the inflated expectations around Big Data. The objective of this invited review paper is to give that scientific background and determine whether Big Data has overcome the peak of inflated expectations. A conceptual model was created, and a literature search in Scopus resulted in 1442 scientific peer reviewed papers. After thorough screening on relevance and classification by the authors, 142 papers remained for further analysis. The area of precision dairy farming (with classes in the primary chain (dairy farm, feed, breed, health, food, retail, consumer) and levels for object of interest (animal, farm, network)), the Big Data-V area (with categories on Volume, Velocity, Variety and other V’s) and the data analytics area (with categories in analysis methods (supervised learning, unsupervised learning, semi-supervised classification, reinforcement learning) and data characteristics (time-series, streaming, sequence, graph, spatial, multimedia)) were analysed. The animal sublevel, with 83% of the papers, exceeds the farm sublevel and network sublevel. Within the animal sublevel, topics within the dairy farm level prevailed with 58% over the health level (33%). Within the Big Data category, the Volume category was most favoured with 59% of the papers, followed by 37% of papers that included the Variety category. None of the papers included the Velocity category. Supervised learning, representing 87% of the papers, exceeds unsupervised learning (12%). Within supervised learning, 64% of the papers dealt with classification issues and exceeds the regression methods (36%). Time-series were used in 61% of the papers and were mostly dealing with animal-based farm data. Multimedia data appeared in a greater number of recent papers. Based on these results, it can be concluded that Big Data is a relevant topic of research within the precision dairy farming area, but that the full potential of Big Data in this precision dairy farming area is not utilised yet. However, the present authors expect the full potential of Big Data, within the precision dairy farming area, will be reached when multiple Big Data characteristics (Volume, Variety and other V’s) and sources (animal, groups, farms and chain parts) are used simultaneously, adding value to operational and strategic decision.