The objective of this work was to examine the effect of different levels of grazing on muscle nutritional fatty acid (FA) profile, including the beneficial n-3 polyunsaturated fatty acids (PUFA) and cis-9, trans-11 (cis-9, trans-11) 18:2 conjugated linoleic acid (CLA). Thirty male Galician Blond (GB) breed calves were randomly assigned to the following three grazing treatments: (1) continuous pasture grazing for 250 days (P); (2) 197-day grazing followed by a 50-day short period of concentrate-based finishing (PC) and (3) 57-day grazing followed by a 165-day long period of concentrate-based finishing (C). Calves kept sucking their mothers up to the time of slaughter. The slaughter weight was similar for all treatments (about 330 kg). Samples of the longissimus thoracis muscle were used for assessment of chemical composition by near infrared reflectance spectroscopy and FA profiles by gas chromatography. Muscle from C calves was fatter and had higher content in total FA, monounsaturated FA (MUFA), cis-9 18:1 than muscle from P calves, whereas PC muscle had generally intermediate values. No significant treatment difference for total saturated FAs (SFA) was found. Content of potentially beneficial n-3 PUFA (18:3n-3, 20:3n-3, 20:5n-3 and 22:6n-3), cis-9, trans-11 CLA and n-6:n-3 ratio were lower and PUFA : SFA ratio were higher in P than in both C and PC calves. Calves fed exclusively on pasture synthesised higher amounts of beneficial FA than calves finished on concentrate. A 50-day period of concentrate-based finishing was sufficient to offset the synthesis of beneficial FA from pasture grazing.

Thirty Landrace × (Landrace × Large White) sows were used to investigate the importance of pre-implantation losses in the embryonic mortality of the early-weaned sow. The sows were allocated at random to one of two lactation lengths, namely, 7 or 42 days. Following weaning and remating the sows were slaughtered at 9 days post coitum. Ovulation rates were similar for both groups (15·3 and 15·1 for the 7-day and 42-day weaned groups respectively). Numbers of embryos present at 9 days post coitum were 12·5 for the 42-day group and 11·2 for the 7-day group and the difference was non-significant. Percentage embryo survival was 83·5% for the 42-day group and 74·3% for the 7-day group; the difference was non-significant. It was concluded that the bulk of embryo loss in the early-weaned sow occurred after the pre-implantation stage and was probably at or around implantation.

1. For 4 weeks before calving in December or January a group of 7 Ayrshire cows each received daily 6 lb. hay and silage to appetite, whilst a second group of 9 received the same roughages and 6–10 lb. concentrates. After calving, cows from both of the pre-calving treatments were placed in each of two post-calving groups of 8 cows. A High treatment received approximately 8 lb./day more concentrates at the same milk yield than the Low treatment. Both groups continued to receive 6 lb. hay/cow/day and silage to appetite. The cows were allowed to graze by day from 21 February and by day and night from 13 April. Hay, at 5 lb./cow/day and reducing rates of concentrates were offered until 8 May.

2. Individual feed intakes were estimated from faecal output and digestibility. Direct measures of the intakes of different treatment groups on indoor feeding agreed fairly closely with the mean individual estimates.

3. The digestible organic matter intake (DOMI) of 1,300 lb. cows in the last stages of pregnancy was increased from 10 up to 14–16 lb./day by giving 8–10 lb./day concentrates. Immediately after calving, the increases in DOMI compared with pre-calving levels were about 2.5 lb./day for cows which received concentrates before calving and 8.5 lb./day for cows which received no concentrates before calving.

4. When all cows had calved and were in full milk production there were no significant differences in DOMI, milk yield or rate of live-weight gain attributable to pre-calving treatment. Mean DOMI on the High and Low post-calving treatments were 23.8 and 19.4 lb./day, mean fat-corrected milk yields 44.5 and 38.8 lb./day and mean rates of live-weight gain 05 and nil lb./day, respectively.

5. DOMI increased by 0.7 and 4.9 lb./day for High and Low post-calving treatments when cows were turned out to night as well as day grazing, and milk yields increased by 1.0 and 2.2 lb./day respectively.

6. Regression equations relating animal production and feed intake, and substitution rates of concentrate usage were calculated. Faecal output and DOMI were closely related to milk yield. When additional concentrates were given the resulting increase in total DOMI was greater when the bulk feed was of low digestibility than when it was of high digestibility.

Skeletal muscle is a highly dynamic and malleable tissue that is able to adapt to different stimuli placed upon it, both during gestation and after birth, ultimately resulting in anatomical changes to muscle fibre composition. Variation in nutrient supply throughout gestation is common, whether in livestock or in the human. The specific effects of maternal nutrition on foetal development are at the forefront of scientific research. However, results describing how different maternal feeding strategies affect skeletal muscle fibre development in the offspring are not fully consistent, even where the same time windows during gestation have been examined. The aim of this study is to determine the effects of increased maternal nutrition (above the recommended levels) on the Musculus semitendinosus phenotype of progeny. In all, 24 pregnant sows were assigned to one of four feeding regimes during gestation; T1 (control group): 30 MJ digestible energy per day (MJ DE/day) throughout gestation, T2: same as that for T1 but increased to 60 MJ DE/day from 25 to 50 days of gestation (dg), T3: same as that for T1 but increased to 60 MJ DE/day from 50 to 80 dg, T4: same as that for T1 but increased nutrition to 60 MJ DE/day from 25 to 80 dg. Light- and heavy-weight littermate pairs of the same sex were selected at birth and individually fed to slaughter (c. 158 days). Histochemical and immunohistochemical staining were used to identify the predominantly oxidative (deep) and less oxidative (superficial) regions of the M. semitendinosus, and to determine total fibre number and proportions of fibre types. The results demonstrate that increased maternal nutrition alters skeletal muscle phenotype in the offspring by changing fibre-type proportions, leading to an increased oxidative capacity due to an increase in Type IIA fibres. No change in total muscle area, total muscle fibre number, or fibre cross-sectional area is observed. The precise molecular mechanism(s) by which these findings occur is being investigated.

1. The digestibility of dry barley and acid-treated moist barley was studied with eight Friesian steers in two consecutive trials each of a duplicated, 2x2 factorial design. In the first trial the diet consisted of either dry or moist (30%) acid-treated barley in the rolled or whole form together with chopped hay; in the second trial rolled or whole, moist (24%) acid-treated barley was given with either chopped hay or silage.

2. No significant difference between the diets in dry-matter intake was observed in the first trial, but in the second trial there was a significantly greater (P< 0·001) intake of dry matter with the hay than with the silage diets.

3. For diets containing either of the moist barleys the digestibility of crude protein was higher when the grain was rolled than when it was whole, the differences being significant (P<0·05) for diets with the 24%-moisture barley. Dry-matter digestibility also was higher for diets containing rolled rather than whole, moist (24%) barley, the difference being significant (P < 0·05) for diets based on silage.

4. Digestibility of starch was significantly greater (P<0·05) when acid-treated moist (24 or 30%) barley was given in the rolled rather than the whole form. Differences in starch digestibility between whole and rolled dry barley were not significant.

5. For all diets the digestibility of crude fibre was greater when the barley was whole than when it was rolled, the difference being significant (P < 0·05) for diets containing hay.

The four sex phenotypes were used to study the relationship between carcass composition and serum profiles of hormones thought to affect growth. Forty calves (10 bulls, 10 steers, 10 heifers and 10 ovariectomized heifers) from Hereford dams crossed with Simmental-Hereford bulls (¾ Simmental-¼ Hereford) were given a high energy diet from 10 to 16 months of age. Sequential blood samples (20-min intervals) representing 6-h windows were obtained from each animal at the outset of the experiment and at 28-day intervals thereafter. Samples were assayed for growth hormone (GH), insulin, triiodothyronine, cortisol, testosterone, oestradiol-17β, urea and albumin. The 9-10-llth rib was dissected into fat, lean and bone, and chemical analysis was performed on the dissected soft tissue. Bulls accumulated more lean tissue and less fat than any other group. Heifers and ovariectomized heifers accumulated the least lean and most fat while steers were intermediate between bulls and the two heifer groups. Bulls may have accumulated more lean and less fat than the heifers due to higher GH and testosterone concentrations, and lower circulating concentrations of cortisol and insulin. The known function of these four hormones and their relative concentrations between bulls and the two female groups were consistent with their suggested role in the relative carcass compositions. The intermediate composition of the steer carcass may have resulted from an interplay between the proteogenic influence of higher GH concentrations, the proteolytic influence of elevated cortisol, the absence of testosterone and the lipogenic influence of higher insulin.

An experiment was carried out to investigate the effects of increasing the digestible undegradable protein (DUP) concentration of concentrates on colostrum production and lamb output from prolific ewe breed types. Sixty triplet-bearing ewes with a mean condition score of 3.75 were allocated to one of five treatments (no. =; 12) for the final 6 weeks of pregnancy. Four of the treatments were offered a restricted grass diet (0.6 kg dry matter (DM) per day) plus one of four isoenergetic and isonitrogenous concentrates (0.56 kg DM per day) that were formulated to provide 25 (P25); 40 (P40); 75 (P75) and 95 (P95) g DUP/kg DM. Control ewes were offered a grass-only diet with the aim of achieving an equivalent total DM intake (1.16 kg DM per day). Concentrate composition had no effect on total diet DM, crude protein or metabolizable energy intakes, but the intake of DUP increased with increasing concentrate DUP level (P < 0.001). Supplementing grass with concentrates led to significant reductions in plasma β-hydroxybutyrate (P < 0.05) and non-esterified fatty acids(P < 0.001) concentrations. Plasma urea concentration tended to be negatively and linearly related to the concentrate DUP level (P < 0.1). Colostrum production and composition were not affected by concentrate type, except for the concentration of gross energy which was highest for P40 ewes. Concentrate feeding led to significant (P < 0.05) increases in colostrum yield 18 h post lambing and colostral outputs of ash, crude protein, total solids and gross energy but resulted in a lower (P < 0.05) colostral immunoglobulin G concentration. Lamb birth weight and total litter weight were not affected by late pregnancy feeding regime. However lamb survival to weaning was reduced significantly (P < 0.05) for P25 and control ewes, resulting in lower levels of lamb output at weaning. The results from this study indicate that offering rumen undegradable rather than rumen degradable protein has no effect on colostrum production and lamb performance when ewes are offered high quality grass-based diets in late pregnancy.

Genetic parameters were estimated for haemoglobin (Hb) levels in sows and piglets as well as sow reproductive performance and piglet survival. Reproductive traits were available between 2005 and 2014 for 7857 litters from 1029 Large White and 858 Landrace sows. In 2012 and 2013, Hb levels, sow BW and sow back fat depth were measured on 348 sows with 529 litters 5 days prior to farrowing. In addition, Hb levels were available for 1127 one-day-old piglets from 383 litters (a maximum of three piglets per litter) of 277 sows with Hb levels. The average Hb levels in sows (sow Hb), their litters (litter Hb, based on average Hb of three piglets) and individual piglets (piglet Hb) were 112 ± 12.6 g/l, 103 ± 15.3 g/l and 105 ± 21.7 g/l, respectively. Heritabilities for Hb levels were 0.09 ± 0.07 for sow Hb, 0.19 ± 0.11 for litter Hb and 0.08 ± 0.05 for piglet Hb. Estimates for the permanent environment effect of sows were 0.09 ± 0.09 for sow Hb, 0.11 ± 0.12 for litter Hb and 0.12 ± 0.03 for piglet Hb. In comparison, heritabilities for both number of stillborn piglets and pre-weaning survival were lower (0.05 ± 0.01 and 0.04 ± 0.01). Sow BW had no significant heritability, while sow back fat depth was lowly heritable (0.10 ± 0.08). Positive genetic correlations were found between sow Hb and litter Hb (0.64 ± 0.47) and between litter Hb and sow back fat depth (0.71 ± 0.53). Higher litter Hb was genetically associated with lower number of stillborn piglets (−0.78 ± 0.35) and higher pre-weaning survival (0.28 ± 0.33). Negative genetic correlations between sow Hb and average piglet birth weight of the litter (−0.60 ± 0.34) and between piglet Hb and birth weight of individual piglets (−0.37 ± 0.32) indicate that selection for heavier piglets may reduce Hb levels in sows and piglets. Similarly, selection for larger litter size will reduce average piglet birth weight (rg: −0.40 ± 0.12) and pre-weaning survival (−0.57 ± 0.13) and may lead to lower litter Hb (−0.48 ± 0.27). This study shows promising first results for the use of Hb levels as a selection criterion in pig breeding programs, and selection for higher Hb levels may improve piglet survival and limit further reduction in Hb levels in sows and piglets due to selection for larger and heavier litters.

We investigated the effect of relative changes in dietary nitrogen (N) and energy supply and the subsequent variations in net portal appearance (NPA) of nitrogenous and energy nutrients on the net amino acid (AA) uptake by the liver and net N supply to the peripheral tissues. Six lambs were catheterised across the splanchnic tissues and received, in a replicated Latin square, one of three dietary treatments. The diets were formulated to either match the requirements of N and energy (C), or supply only 0.8 of the N requirement (LN) or 0.8 of the energy requirement (LE). Net fluxes of AA and urea-N were measured across the portal-drained viscera, and estimation of arterial hepatic flow allowed the estimation of hepatic fluxes. Catheters were implanted into the portal and hepatic veins as well as in the abdominal aorta for the measurement of AA fluxes. Animals fed the LN diet showed more efficient N retention (0.59 of digested N) than did the C and LE diet (0.50 and 0.33, respectively; P < 0.001). The NPA of total AA-N for the LN diet was only 0.60 of the value measured for the control (C) diet (P < 0.01). Despite this, the total estimated AA-N net splanchnic fluxes were not significantly different across the three diets (3.3, 1.9 and 2.6 g total AA-N/day for C, LN and LE, respectively, P = 0.52). Thus, different metabolic regulations must have taken place across the liver between the three experimental diets. A combination of decreased net uptake of total AA-N by the liver of animals in the LN diet (0.61 of the C diet; P = 0.002) and reduced urinary urea-N production (0.52 of the C diet; P = 0.001) spared AA from catabolism in the LN diet relative to the other two diets. For the LE diet, the urinary urea-N output was 1.3 times the value of the C diet (P = 0.01). This may relate to an increased catabolism of AA by the muscle and/or, to a lesser extent, to an increased utilisation of AA for gluconeogenesis in the liver. These effects may explain the reduced whole body protein retention observed with the LE diet.

The productivity of cows grazing on veld was studied over four breeding seasons. Different amounts of concentrates were given to three groups of cows during winter and up to 8 weeks post partum. Half of the cows in each group had their calves weaned early (150 days) and the others at the normal time (240 days). Cows given concentrates produced more calves than those given none but time of weaning had no consistent effect on successful conception rates (as judged by subsequent calving rate).

Probit analyses were used to determine the relationship between seasonal body-weight change in the cow and the probability of successful conception. The estimated percentage body-weight changes from autumn peak to mean body weight at the beginning and end of the mating season, which would be followed by successful conception rates of 50%, 75% and 90%, were −14%, −6% and +1% of autumn body weight, respectively.

The practical implications of these results are discussed.

Broiler poultry litter was deep-stacked (2·5 m high) in three ways: (1) uncovered, (2) covered with 0·1524 mm clear polyethylene and (3) surface-watered to form a 2·5 cm crust upon drying. After 30 days, each litter was used to formulate two diets containing proportionately 0·25 or 0·50 poultry litter (dry-matter basis). Urea was used as the nitrogen source in the control diet. All diets contained 100 g/kg cottonseed hulls, 20 g/kg limestone and cracked maize. Each of the seven diets was offered to 12 crossbred steers (two pens per diet; initial body weight 204 kg) for 84 days. Blood was collected and body weights measured every 28 days. After 84 days, liver biopsies were obtained from four steers per diet and an additional three steers per diet were penned individually and nutrient apparent digestibilities were determined. Steers gained 1·6 kg/day on the urea diet and 1·2, 1·3 and 1·2 kg/day on the diets containing 0·25 litter, uncovered, covered or watered, respectively. Steers consuming the 0·50 litter diets gained 1·0, 0·9 and 1·0 kg/day, respectively (significant linear decrease; P < 0·01). Litter depressed (P < 0·04) apparent dry matter, organic matter and gross energy digestibilities regardless of stacking method. However, nitrogen apparent digestibility was decreased by uncovered and watered litter only. Increased proportion of litter in the diet resulted in increased serum sorbitol dehydrogenase and aspartate aminotransferase and liver copper concentrations (P < 0·07); however, clinical copper toxicosis (haemolytic crisis) was not observed. Dietary inclusion of broiler poultry litter also increased serum phosphorus and decreased serum calcium concentrations (P < 0·07). Covering deep-stacked litter preserved nitrogen quality, but improvements over uncovered litter were not of sufficient magnitude to elicit improved animal performance in this study.

A greater understanding of the rumen microbiota and its function may help find new strategies to improve feed efficiency in cattle. This study aimed to investigate whether the cattle breed affects specific ruminal taxonomic microbial groups and functions associated with feed conversion ratio (FCR), using two genetically related Angus breeds as a model. Total RNA was extracted from 24 rumen content samples collected from purebred Black and Red Angus bulls fed the same forage diet and then subjected to metatranscriptomic analysis. Multivariate discriminant analysis (sparse partial least square discriminant analysis (sPLS-DA)) and analysis of composition of microbiomes were conducted to identify microbial signatures characterizing Black and Red Angus cattle. Our analyses revealed relationships among bacterial signatures, host breeds and FCR. Although Black and Red Angus are genetically similar, sPLS-DA detected 25 bacterial species and 10 functions that differentiated the rumen microbial signatures between those two breeds. In Black Angus, we identified bacterial taxa Chitinophaga pinensis, Clostridium stercorarium and microbial functions with large and small subunits ribosomal proteins L16 and S7 exhibiting a higher abundance in the rumen microbiome. In Red Angus, nonetheless, we identified the poorly characterized bacterial taxon Oscillibacter valericigenes with a higher abundance and pathways related to carbohydrate metabolism. Analysis of composition of microbiomes revealed that C. pinensis and C. stercorarium exhibited a higher abundance in Black Angus compared to Red Angus associated with FCR, suggesting that these bacterial species may play a key role in the feed conversion efficiency of forage-fed bulls. This study highlights how the discovery of signatures of bacterial taxa and their functions can be used to harness the full potential of the rumen microbiome in Angus cattle.

Two contrasting replacement strategies are used by Irish beef farmers to select replacement females – animals sourced from within the suckler beef herd and sourced from the dairy herd. The objective of this study was to investigate the effect of replacement strategy (i.e. beef v. beef×dairy (BDX)) on cow and calf performance using data from the national beef database across a range of beef and dairy breeds. The association between replacement strategy and calving difficulty score, calving interval, weaning weight, weaning price and all carcass traits was investigated using a mixed model. The effect of replacement strategy on cow survival, calving dystocia and calf perinatal mortality was quantified using logistic regression. Beef cows were older (10.92 days; P<0.001) at their first calving, but were 1.15 times (P<0.01) more likely to survive to a subsequent lactation compared with BDX cows. Calving interval was 1.53 days shorter (P<0.001) for BDX compared with beef cows. Greater calving difficulty and calving dystocia was associated with beef cows (P<0.001) relative to BDX. However, BDX were 1.36 times (P<0.001) more likely to have a dead calf at birth relative to beef cows. Calves weaned from BDX were heavier (18.49 kg; P<0.001) at weaning, reached slaughter 12.8 days earlier (P<0.001), had 7.99 kg heavier carcass (P<0.001) and a greater fat score (P<0.001) compared with the progeny of beef cows. Beef cow progeny had a superior conformation score (0.5; P<0.001) and achieved a greater price per kilogram (P<0.001) compared with progeny from BDX. Beef cull cows had a heavier carcass (5.58 kg), superior carcass conformation, greater carcass price per kilogram and greater overall carcass value (P<0.001) than BDX. Results from this study show that replacement strategy is of fundamental importance depending on the type of system implemented by farmers and consideration must be given to the traits of importance within the context of the individual production system.

A study was carried out on six lowland farms in Northern Ireland over 2 years to examine the effect on labour input and lamb output of adopting an outdoor (grass-based) lambing system in comparison to an indoor lambing system. Each farm had four crossbred ewe genotypes – Bluefaced Leicester ✕ Scottish Blackface (BLXB), Texel ✕ Scottish Blackface (TXB), Suffolk ✕ Cheviot (SXCH) and Texel ✕ Cheviot (TXCH) ewes. The ewes were divided into three groups balanced for live weight and condition score and mated with Texel, Suffolk or Beltex rams. Half of the ewes lambed indoors and the other half were turned out to grass three to 6 weeks before lambing and lambed outdoors. BLXB ewes were the most prolific of the four ewe genotypes producing 1·99 lambs per ewe lambed compared with 1·75 for TXB, 1·76 for SXCH and 1·64 for TXCH (P < 0.001). A greater proportion of SXCH ewes lambed without assistance (0·82) compared with BLXB (0.70), TXB (0.71) and TXCH (0.74) ewes (P < 0.01) and subsequently less time was spent lambing SXCH ewes (P < 0.01). This advantage of the SXCH was more marked in the outdoor than in the indoor system (P < 0.01) in terms of lamb output, each of the four ewe genotypes performed similarly in the indoor and outdoor lambing systems. Lambs born in the outdoor system weighed 0.2 kg more at birth compared with those born indoors (P < 0.05). Lamb mortality and lamb output were similar in both systems. Less time was spent catching and moving ewes in the outdoor system compared with the indoor system (P < 0.01). Beltex-sired lambs weighed less at birth (4.9 kg) compared with Texel- (5.1 kg) (P < 0.10) and Suffolk-(5.3 kg) (P < 0.001) sired lambs and had lower live-weight gains from birth to 6 weeks and from birth to weaning (P < 0.001) and lower output of weaned lamb (P < 0.05). The results of this study demonstrate that, compared with indoor lambing systems, similar levels of performance can be achieved through adopting outdoor, grass-based systems. The lack of a significant interaction between ewe or ram genotype and lambing system indicates that all of the genotypes are suitable for incorporating into an outdoor lambing system.

In immunocastrated (IC) pigs, revaccination (V2) increases lipid deposition (LD) because of increased voluntary feed intake; but little is known on associated effect of diet composition on partitioning of nutrients in IC pigs. Digestibility measurements, N and energy balances in respiration chambers were performed in two subsequent stages in four replicates of two male littermates to determine the changes between 85 (stage 1) and 135 (stage 2) kg live weight due to combined effect of IC, growth and increased feed intake (IC/growth). During stage 1, pigs received a standard low-fat diet (LF diet; 2.5% dry matter (DM) of fat fed at 2.27 MJ metabolizable energy (ME)/kg BW0.60 per day), whereas during stage 2, feed intake was increased to 2.47 MJ ME/kg BW0.60 per day and one littermate was fed LF diet whereas the second received a fat-enriched diet (HF diet; 8.9% DM of fat) to determine the effect of increased dietary fat content on energy utilization in IC pigs. Results from N balance and measurements of gas exchanges were used to calculate respiratory quotient (RQ), heat production (HP), nutrient contribution to fat retention, components of HP, protein deposition (PD) and LD. Nutrients and energy apparent digestibility coefficients, methane losses and N retention (P<0.05) increased with IC/growth. Despite higher ME intake, total HP remained similar (1365 kJ/kg of BW0.60 per day; P=0.47) with IC/growth. Consequently, total retained energy (RE) increased with IC/growth (from 916 to 1078 kJ/kg of BW0.60 per day; P<0.01) with a higher fat retention (625 to 807 kJ/kg BW0.60 per day; P<0.01), originating mainly from carbohydrates associated with a higher lipogenesis (536 to 746 kJ/kg BW0.60 per day; P<0.01) and RQ (1.095 to 1.145; P<0.01). Both PD (from 178 to 217 g/day; P=0.02) and LD (from 227 to 384 g/day; P<0.01) increased due to IC/growth. Feeding HF diet after IC was associated with increased crude fat digestibility (P<0.01) and increased RE as fat (807 to 914 kJ/kg BW0.60 per day; P=0.03), originating mainly from dietary fat (P<0.01) and resulting in increased LD (384 to 435 g/day; P<0.01) and lower RQ (from 1.145 to 1.073; P<0.01). Altogether, present results indicate that increased fatness of IC pigs is a result of increased daily LD caused by higher energy intake and lower basal metabolic rate. In addition, LD is further enhanced by dietary energy enrichment with fat after V2.

An understanding of the perceived importance of a variety of factors affecting the ease of handling of sheep and the interactions between these factors is valuable in improving profitability and welfare of the livestock. Many factors may contribute to animal behaviour during handling, and traditionally these factors have been assessed in isolation under experimental conditions. A human social component to this phenomenon also exists. The aim of this study was to gain a deeper understanding of the importance of a variety of factors affecting ease of handling, and the interactions between these from the perspective of the livestock transporter. Qualitative interviews were used to investigate the factors affecting sheep behaviour during handling. Interview transcripts underwent thematic analysis. Livestock transporters discussed the effects of attitudes and behaviours towards sheep, helpers, facilities, distractions, environment, dogs and a variety of sheep factors including breed, preparation, experience and sex on sheep behaviour during handling. Transporters demonstrated care and empathy and stated that patience and experience were key factors determining how a person might deal with difficult sheep. Livestock transporters strongly believed facilities (ramps and yards) had the greatest impact, followed by sheep experience (naivety of the sheep to handling and transport) and breed. Transporters also discussed the effects of distractions, time of day, weather, dogs, other people, sheep preparation, body condition and sheep sex on ease of handling. The concept of individual sheep temperament was indirectly expressed.

One hundred first lactation Friesian dairy heifers were used to investigate the effect of level of feeding n i late pregnancy (83·6 or 64·6 MJ metabolizable energy (ME) per head daily and around the time of first artificial insemination (AI) (weeks 6 to 18 of lactation: 146·8 or 119·8 MJ ME per head daily) on reproductive performance.

Heifers receiving the high level of feeding in lactation had a successful pregnancy rate to first AI of 0·42 compared with 0·63 for heifers receiving the lower level of feeding. Heifers receiving the higher level of feeding in late pregnancy followed by the lower level in lactation had a pregnancy rate of 0·72 o t first AI resulting in a median interval from calving to pregnancy of 75 days compared with figures of 0·35 and 95 days respectively, for heifers receiving the higher levels of feeding throughout the experiment (P < 0·001).

Blood samples were taken from all heifers 2 weeks before and on weeks 1, 5, 9, 13 and 18 after calving, and were analysed for 13 components. Of the blood components measured, only p"-hydroxy-butyrate concentrations, particularly at week 9, were affected by the nutritional treatments imposed and consistently related to fertility (P < 0·01 to P < 0·001).

Milk yield and live-weight change, individually and as the components of net energy output, showed the strongest relationships with reproductive performance (P < 0·01 to P < 0·001). The three variables which together accounted for the highest proportion (0·30) of the variation in days to successful pregnancy were net energy output at AI, (3-hydroxy-butyrate at week 9, and mean tail score in weeks 10 o t 13. These enabled the calving to successful pregnancy interval for an individual or 100 first lactation heifers to be predicted with a 95% confidence interval of ±58 days or ±8·6 days, respectively.

Diets combining herbage and total mixed rations (TMR) are increasingly used in temperate regions for feeding ruminants, but little information is available regarding the effects on nutrient intake and digestion of this feeding management in beef cattle. The aim of this study was to determine the effects of combining TMR (10% CP and 13% ADF), and legume-based herbage (14% CP and 27% ADF) on intake, nutrient digestion, ruminal fermentation, microbial N flow and glucose and nitrogen metabolism in heifers. The experiment was a 3×3 Latin square design replicated three times; each period lasted 18 days (10 adaptation days and 8 measurement days). Nine cross-bred (Aberdeen Angus×Hereford) heifers (214±18 kg) fitted with permanent rumen catheters and housed in individual metabolic cages were assigned to one of three treatments: 24 h access to TMR (T), 24 h access to herbage (H) or combined diets with 18 h access to TMR and 6 h access to herbage (T+H). Data were evaluated using a mixed model. Animals fed T+H (TMR 71% and herbage 29%) diets tended to have a higher dry matter intake as a proportion of their BW than animals fed T. The T+H diet did not change ruminal fermentation (pH, N–NH3 and volatile fatty acids) or the N metabolism relative to the T diet, but increased the glucagon concentration and altered glucose metabolism. Conversely, animals fed T+H had increased purine derivatives excretion, increased N use efficiency for microbial protein synthesis and decreased plasma urea and urinary N excretion relative to animals fed H diet. The use of combined diets led to consumption of nutrients similar to a TMR diet, without reducing nutrient use and could improve N utilization compared with the herbage-only diet.

Protein content reduction in broiler breeder diets has been increasingly investigated. However, broiler breeders reared on low protein diets are characterized by a deterioration of the feather condition. Furthermore, polydipsia induced by controlled feed intake increases litter moisture and as a consequence pododermatitis. This project aimed to study the litter moisture, pododermatitis and feather condition of breeders fed with a 25% reduced balanced protein (RP) diet during the rearing and laying period over three successive generations. The experiment started with two treatments for the F0 generation: control (C) group fed with standard C diets and RP group fed with RP diets. The female F0-progeny of each treatment was divided into the two dietary treatments as well, resulting in four treatments for the F1 generation: C/C, C/RP, RP/C and RP/RP (breeder feed in F0/F1 generation). The RP diet fed breeders received on average 10% more feed than C diet fed breeders to achieve the same target BW. The female F1-progeny of each treatment were all fed with C diets which resulted in four treatments for the F2 generation: C/C/C, C/RP/C, RP/C/C and RP/RP/C (breeder feed in F0/F1/F2 generation). Litter moisture, footpad and hock dermatitis were recorded at regular intervals throughout the experimental period in all three generations. For the F0 and F1 generation, the pens of breeders receiving C diets had significantly higher litter moisture than the RP diets fed groups (P<0.05), resulting in an elevated footpad dermatitis occurrence (FDO) (P<0.05). No difference was found in the F2 generation. The feather condition was scored during the laying period for each generation. F0 and F1 breeders reared on the RP diets had poorer feather condition than those receiving the C diets (P<0.05). The C/RP breeders had a significantly poorer feather condition than RP/RP breeders (P<0.05). For the F2 generation, RP/RP/C breeders had a significantly better feather condition compared with the other three groups (P<0.05). The RP/C/C breeders were significantly better feathered than C/C/C breeders (P<0.05). In conclusion, providing RP diets to broiler breeders improved litter condition and hence reduced FDO whereas impaired feather condition. Furthermore, positive transgenerational effects of the maternal RP diets on the feather condition may be inferred, hence potentially altering the welfare status.

Estrus synchronization is important for optimal management of gilt reproduction in pig farms. Hormonal treatments, such as synthetic progestogens, are used on a routine basis, but there is a growing demand for non-hormonal alternative breeding tools. Before puberty, gilts exhibit a ‘waiting period,’ related to the ovarian development and gonadotrophin secretions, during which external stimulations, such as boar exposure, could induce and synchronize first ovulation. Practical non-invasive tools for identification of this period in farms are lacking. During this period, urinary oestrone levels are high, but urine sampling is difficult in group-housed females. The aim of this work was to search for specific biomarkers of the ‘waiting period’ in saliva and urine. In total, nine 144- to 147-day-old Large White gilts were subjected to trans-abdominal ultrasonography three times a week for 5 weeks until puberty detection (week –5 to week –1 before puberty). Urine and saliva samples were collected for oestrone assay to detect the ‘waiting period’ and for metabolome analysis using 1H-nuclear magnetic resonance spectroscopy to detect potential biomarkers of the ‘waiting period.’ Gilts were slaughtered 7 days after puberty detection for puberty confirmation. Results were consistent with ultrasonography data for six gilts. Urine and saliva samples from these six gilts were analyzed. Urinary estrone concentration significantly increased 2 weeks before puberty detection. Metabolome analysis of urine samples allowed the identification of 78 spectral bins, among them, 42 low-molecular-weight metabolites were identified. Metabolome analysis of salivary samples allowed the identification of 59 spectral bins, among them, 23 low-molecular-weight metabolites were detected and 17 were identified. No potential biomarker was identified in urinary samples. In saliva, butyrate and 2HOvalerate, 5.79 ppm (putatively uridine), formate, malonate and propionate could be biomarker candidates to ascertain the pre-puberty period in gilt reproduction. These results confirm that non-invasive salivary samples could allow the identification of the physiological status of the gilts and presumably the optimal time for application of the boar effect. This could contribute to synchronize puberty onset and hence to develop non-hormonal breeding tools.