The growth performance, carcass quality and digestive efficiency of growing pigs were used to compare sweet lupin seed meal (SLSM) to soya bean meal and meat meal as a source of supplementary protein to wheat in diets for pigs, and to study the influence of low levels of lysine and methionine, high levels of crude fibre and oil, and possible toxic factors in SLSM on the use of SLSM in such diets.

The growth rate and food utilization of pigs between 20 and 80 kg live weight were in the order soya bean meal > SLSM > meat meal, but only the difference between soya bean meal and meat meal was significant. These feeds did not differ significantly in their effects on the proportion of lean in the ham. Adding lysine to the SLSM diet improved growth performance but adding methionine did not. The digestibility of crude fibre in diets containing SLSM was greater than that in diets containing soya bean meal; the digestible energy contents of SLSM and soya bean meal were 4·13±0·05 and 4·16±0·08 Mcal/kg dry matter, respectively. Pigs fed on a diet containing 27·5% SLSM grew faster but utilized food as efficiently when fed ad libitum as on a restricted scale of feeding. The subcutaneous fat of pigs fed on SLSM had a higher iodine number than that of pigs fed on soya bean meal.

Haematological profiles indicate the health status of an animal and can be used to identify sub-clinical stress responses. The objectives of the study were to examine (i) the effect of breed and plane of nutrition, on haematological profiles of artificially reared Holstein-Friesian and Jersey bull calves in response to gradual weaning, and (ii) the effect of breed on immune response genes in bovine whole blood using real-time quantitative PCR. Holstein-Friesian and Jersey bull calves were group housed indoors and individually fed using an automatic feeder. They were allocated to a high, medium or low plane of nutrition, based on milk replacer (MR) and concentrate. The nutrition treatments were calculated using National Research Council guidelines in order to achieve a high, medium or low growth rate for each respective breed. During the weaning phase MR was gradually reduced over a 14-day (d) period (d −13 to d 0). Calves were blood sampled on d −14, −6, −3, 0, 1, 3, 8 and 14 relative to weaning (d 0) for subsequent haematological analysis. On d −14, 1 and 8, a subset of eight Holstein-Friesian calves randomly selected from the medium nutrition treatment and eight Jersey calves randomly selected from the high nutrition treatment, were blood sampled for gene expression profiling, targeting biomarkers of weaning stress. These two treatment groups were chosen to examine the effect of breed on expression of the genes of interest, as energy intake and animal performance were similar. There was no effect of breed×plane of nutrition interaction nor effect of plane of nutrition on any variable measured (P>0.05). Gradual weaning produced differential biological responses in the two breeds evidenced by breed×time interactions for lymphocyte, monocyte and red blood cell number, plasma haemoglobin and haptoglobin concentrations (P<0.05). The typical stress response consisting of neutrophilia and lymphopaenia was not observed for any treatment. An immune response to gradual weaning was observed as the relative gene expression level of the pro-apoptotic gene, Fas, increased on d 1 relative to d −14 (P<0.05). Relative gene expression levels were greater in Jersey calves compared with Holstein-Friesian for the pro-inflammatory cytokine CXCL8 (P=0.05) and the glucocorticoid receptor, GRα (P<0.05). The increased levels of these transcripts suggest that Jersey calves may have a more sensitive immune system compared with Holstein-Friesian.

A beef progeny test was organized for 66 British Friesian bulls standing at AI centres in England. Eighty-one progeny groups averaging 8-5 steers each were reared on the farms of various co-operating organizations and their growth and carcass characters were recorded. Heritability of various measurements of gain varied from 0 to 0·34, of carcass conformation measures from 0·24 to 0·50, of muscle and fat percentage in the rib joint was 0·58 and 0·46 respectively, of other measures of fatness varied from 0·04 to 0·18, of weight of feet was 0·4 and of weight of hide 0·5.

Phenotypic correlations among beef characters gave no indication that carcass composition could be predicted from the external carcass measurements or subjective scores used in this study. Genetic correlations suggested that selection for weight for age would produce a fatter and more compact carcass. Genetic correlations were high and negative between milk yield (contemporary comparison) and weight for age, carcass weight/length, and blockiness of leg, and high and positive between milk yield, and carcass depth/length and percentage bone in the rib joint. Their standard errors were also high.

Weaning is known to induce important nutritional and energetic stress in piglets. Low-birthweight (LBW) piglets, now frequently observed in swine production, are more likely to be affected. The weaning period is also associated with dysfunctional immune responses, uncontrolled inflammation and oxidative stress conditions that are recognized risk factors for infections and diseases. Mounting evidence indicates that mitochondria, the main cellular sources of energy in the form of adenosine 5′ triphosphate (ATP) and primary sites of reactive oxygen species production, are related to immunity, inflammation and bacterial pathogenesis. However, no information is currently available regarding the link between mitochondrial energy production and oxidative stress in weaned piglets. The objective of this study was to characterize markers of cellular and mitochondrial energy metabolism and oxidative status in both normal-birthweight (NBW) and LBW piglets throughout the peri-weaning period. To conduct the study, 30 multiparous sows were inseminated and litters were standardized to 12 piglets. All the piglets were weighted at day 1 and 120 piglets were selected and assigned to 1 of 2 experimental groups: NBW (n = 60, mean weight of 1.73 ± 0.01 kg) and LBW piglets weighing less than 1.2 kg (n = 60, 1.01 ± 0.01 kg). Then, 10 piglets from each group were selected at 14, 21 (weaning), 23, 25, 29 and 35 days of age to collect plasma and organ (liver, intestine and kidney) samples. Analysis revealed that ATP concentrations were lower in liver of piglets after weaning than during lactation (P < 0.05) thus suggesting a significant impact of weaning stress on mitochondrial energy production. Oxidative damage to DNA (8-hydroxy-2′-deoxyguanosine, 8-OHdG) and proteins (carbonyls) measured in plasma increased after weaning and this coincides with a rise in enzymatic antioxidant activity of glutathione peroxidase (GPx) and superoxide dismutase (SOD) (P < 0.05). Mitochondrial activities of both GPx and SOD are also significantly higher (P < 0.05) in kidney of piglets after weaning. Additionally, oxidative damage to macromolecules is more important in LBW piglets as measured concentrations of 8-OHdG and protein carbonyls are significantly higher (P < 0.05) in plasma and liver samples, respectively, than for NBW piglets. These results provide novel information about the nature, intensity and duration of weaning stress by revealing that weaning induces mitochondrial dysfunction and cellular oxidative stress conditions which last for at least 2 weeks and more severely impact smaller piglets.

Understanding of biological impact of proteome profile on meat quality is vital for developing different approaches to improve meat quality. Present study was conducted to unravel the differences in biochemical, ultrastructural and proteome profile of longissimus dorsi muscle between buffaloes (Bubalus bubalis) of different age groups (young v. old). Higher (P<0.05) myofibrillar and total protein extractability, muscle fibre diameter, and Warner-Bratzler shear force (WBSF) values was observed in old buffalo meat relative to meat from young buffaloes. Scanning electron microscopy photographs revealed reduced fibre size with increased inter-myofibrillar space in young compared with old buffalo meat. Transmission electron microscopy results revealed longer sarcomeres in young buffalo meat relative to meat from old buffaloes. Proteomic characterization using two-dimensional gel electrophoresis (2DE) found 93 differentially expressed proteins between old and young buffalo meat. Proteome analysis using 2DE revealed 191 and 95 differentially expressed protein spots after 6 days of ageing in young and old buffalo meat, respectively. The matrix assisted laser desorption ionization time-of flight/time-of flight mass spectrometry (MALDI-TOF/TOF MS) analysis of selected gel spots helped in identifying molecular markers of tenderness mainly consisting of structural proteins. Protein biomarkers identified in the present study have the potential to differentiate meat from young and old buffaloes and pave the way for optimizing strategies for improved buffalo meat quality.

A total of 19 376 test day (TD) milk yield records from the first three lactations of 1618 cows daughters of 162 sires were used to estimate genetic and phenotypic parameters and determine the relationship between daily milk yield and lactation milk yield in the Sahiwal cattle in Kenya. Variance components were estimated using animal models based on a derivative free restricted maximum likelihood procedure. Variance components were estimated using various univariate and multi-trait fixed regression test day models (TDM) that defined contemporary groups either based on the year-season of calving (YSCV) or on the year-season of TD milk sampling (YSTD). Variance components were influenced by CG which resulted in differences in heritability and repeatability estimates between TDM. Models considering YSTD resulted in higher additive genetic variances and lower residual variances compared with models in which YSCV was considered. Heritability estimates for daily yield ranged from 0.28 to 0.46, 0.38 to 0.52 and 0.33 to 0.52 in the first, second and third lactation, respectively. In the first and second lactation, the heritability estimates were highest between TD 2 and TD 4. Genetic correlations among daily milk yields ranged from 0.41 to 0.93, 0.50 to 0.83 and 0.43 to 86 in the first, second and third lactation, respectively. The phenotypic correlations were correspondingly lower. Genetic correlations were different from unit when fitting multi-trait TDM. Therefore, a multiple trait model would be more ideal in determining the genetic merit of dairy sires and bulls based on daily yield records. Genetic and phenotypic correlations between daily yield and lactation yields were high and positive. Genetic correlations ranged from 0.84 to 0.99, 0.94 to 1.00 and 0.94 to 0.97 in the first, second and third lactations, respectively. The corresponding phenotypic correlation estimates ranged from 0.50 to 0.85, 0.50 to 0.83 and 0.53 to 0.87. The high genetic correlation between daily yield and lactation yield imply that both traits are influenced by similar genes. Therefore daily yields records could be used in genetic evaluation in the Sahiwal cattle breeding programme.

Frequent BW monitoring of growing pigs can be useful for identifying production (e.g. feeding), health and welfare problems. However, in order to construct a tool which will properly recognize abnormalities in pigs’ growth a precise description of the growth process should be used. In this study we proposed a new model of pig growth accounting for daily fluctuations in BW. Body weight measurements of 1710 pigs (865 gilts and 843 barrows) originating from five consecutive batches from a Danish commercial farm were collected. Pigs were inserted into a large pen (maximum capacity=400) between November 2014 and September 2015. On average, each pig was observed for 42 days and weighed 3.6 times a day when passing from the resting to feeding area. Altogether, 243,160 BW measurements were recorded. A multilevel model of pig growth was constructed and fitted to available data. The BW of pigs was modeled as a quadratic function of time. A diurnal pattern was incorporated into the model by a cosine wave with known length (24 h). The model included pig effect which was defined as a random autoregressive process with exponential correlation. Variance of within-pigs error was assumed to increase with time. Because only five batches were observed, it was not possible to obtain the random effect for batch. However, in order to account for the batch effect the model included interactions between batch and fixed parameters: intercept, time, square value of time and cosine wave. The gender effect was not significant and was removed from the final model. For all batches, morning and afternoon peaks in the frequency of visits to the feeding area could be distinguished. According to results, pigs were lighter in the morning and heavier in the evening (minimum BW was reached around 1000 h and maximum around 2200 h). However, the exact time of obtaining maximum and minimum BW during the day differed between batches. Pigs had access to natural light and, therefore, existing differences could be explained by varying daylight level during observations periods. Because the diurnal amplitude for pig growth varied between batches from 0.9 to 1.4 kg, BW monitoring tools based on frequent measurements should account for diurnal variation in BW of pigs. This proposed description of growth will be built into a monitoring tool (a dynamic linear model) and applied to farm data in future studies.

Reproductive efficiency in the dairy herd is the most important factor for its economic success and a major concern for dairy farmers when using artificial insemination (AI) or natural service (NS). Our objectives were to estimate, compare and analyse the costs associated with breeding cattle by do-it-yourself (DIY) AI and NS and identify the factors that influence them, under typical dairy farming conditions in Greece. A simulation study was designed based on data from 120 dairy cattle farms that differed in size (range 40 to 285 cows) and milk production level (4000 to 9300 kg per cow per year). Different scenarios were employed to estimate costs associated directly with AI and NS as well as potentially extended calving intervals (ECI) due to AI. Results showed that bull maintenance costs for NS were €1440 to €1670 per year ($1,820 to $2,111). Direct AI costs were higher than those for NS for farms with more than 30 cows and ECI constituted a considerable additional burden. In fact, amongst the factors that affected the amount of milk needed to cover total extra AI costs, number of days open was the dominant one. Semen, feed and heifer prices had a very small effect. When, hypothetically, use of NS bulls results in a calving interval of 12 months, AI daughters with a calving interval of 13.5 months have to produce about 705 kg of additional milk in order to cover the extra cost. Their actual milk production, however, exceeds this limit by more than 25%. When real calving intervals are considered (13.0 v. 13.7 months for NS and AI, respectively) AI daughters turn out to produce more than twice the additional amount of milk needed. It was concluded that even under less than average management conditions, AI is more profitable than the best NS scenario. The efficient communication of this message should be a primary concern of the AI industry.

The supplementing of sow diets with lipids during pregnancy and lactation has been shown to reduce sow condition loss and improve piglet performance. The aim of this study was to determine the effects of supplemental palm oil (PO) on sow performance, plasma metabolites and hormones, milk profiles and pre-weaning piglet development. A commercial sow ration (C) or an experimental diet supplemented with 10% extra energy in the form of PO, were provided from day 90 of gestation until weaning (24 to 28 days postpartum) in two groups of eight multiparous sows. Gestation length of PO sows increased by 1 day (P<0.05). Maternal BW changes were similar throughout the trial, but loss of backfat during lactation was reduced in PO animals (C: −3.6±0.8 mm; PO: −0.1±0.8 mm; P<0.01). Milk fat was increased by PO supplementation (C day 3: 8.0±0.3% fat; PO day 3: 9.1±0.3% fat; C day 7: 7.8±0.5% fat; PO day 7: 9.9±0.5% fat; P<0.05) and hence milk energy yield of PO sows was also elevated (P<0.05). The proportion of saturated fatty acids was greater in colostrum from PO sows (C: 29.19±0.31 g/100 g of fat; PO: 30.77±0.36 g/100 g of fat; P<0.01). Blood samples taken on 105 days of gestation, within 24 h of farrowing, day 7 of lactation and at weaning (28±3 days post-farrowing) showed there were no differences in plasma concentrations of triacylglycerol, non-esterified fatty acids, insulin or IGF-1 throughout the trial. However, circulating plasma concentrations of both glucose and leptin were elevated during lactation in PO sows (P<0.05 and P<0.005, respectively) and thyroxine was greater at weaning in PO sows (P<0.05). Piglet weight and body composition were similar at birth, as were piglet growth rates throughout the pre-weaning period. A period of 7 days after birth, C piglets contained more body fat, as indicated by their lower fat-free mass per kg (C: 66.4±0.8 arbitrary units/kg; PO: 69.7±0.8 arbitrary unit/kg; P<0.01), but by day 14 of life this situation was reversed (C: 65.8±0.6 arbitrary units/kg; PO: 63.6±0.6 arbitrary units/kg; P<0.05). Following weaning, PO sows exhibited an increased ratio of male to female offspring at their subsequent farrowing (C: 1.0±0.3; PO: 2.2±0.2; P<0.05). We conclude that supplementation of sow diets with PO during late gestation and lactation appears to increase sow milk fat content and hence energy supply to piglets. Furthermore, elevated glucose concentrations in the sow during lactation may be suggestive of impaired glucose homoeostasis.

The aim of this study was to evaluate the carcass and meat characteristics of eight muscles from bulls with distinct growth paths. A total of 40 Alentejana male calves were allocated to two distinct feeding regimes. In the continuous growth (CG) system, the animals were fed concentrates plus hay and were slaughtered at 18 months of age. On the other hand, in the discontinuous growth (DG) system, the animals were fed hay until 15 months of age; the cattle were then fed the same diet provided to the CG group from 15 to 24 months of age. The DG reduced hot carcass weight, fatness and dressing %, but the proportions of fat, bone and muscle tissues in the leg were not affected. In contrast, there was a positive impact of compensatory growth on supraspinatus, triceps brachii, semitendinosus, biceps femoris muscle tenderness, overcoming the negative effects of age at slaughter. The reasons for such improvement in meat tenderness were not related to intra-muscular fat content or myofibrillar protein degradation values. An association between tenderness and muscle collagen properties was not established. The results indicate that the compensatory growth has a muscle-dependent effect.

Two trials were undertaken to study the effects of cafeteria feeding systems on the feed intake, animal performance and carcass characteristics of growing lambs. Trial 1 was designed to compare conventional and cafeteria feeding systems in terms of the growth of individually reared lambs. For this assay, 26 weaned Merino lambs (15.5 ± 0.20 kg live weight) were assigned to three dietary treatment groups: (1) a control group fed barley straw and commercial concentrate under a conventional feeding system, (2) group W100S, fed soya-bean meal, whole barley grain and a mineral-vitamin supplement under a cafeteria feeding system, and (3) group W100S-T, fed as in the W100S treatment but allowing the lambs an initial training period so they could learn to identify a number of feeds. The feeding system had no significant effect ( P>0.05) on either average daily live-weight gain, carcass weight, or carcass conformation. The food conversion ratio was lower ( P < 0.05) for the cafeteria-reared animals (2.9 ± 0.16 v. 2.5 ± 0.08 g dry-matter intake per g average daily gain) than those of the control group. This might be related to the higher crude protein intake seen in the cafeteria groups (150 ± 5.6 v. 208 ± 12.5 g per animal per day; P < 0.001).

In trial 2, cafeteria and conventional feeding system were compared in terms of the growth of feedlot lambs. Two hundred weaned Merino lambs (13.1 ± 0.10 kg) were divided into two experimental groups: (1) a control group, offered commercial concentrate and barley straw, and (2) a cafeteria group fed the same diet as W100ST in trial 1. The average daily gain (282 ± 5.8 and 309 ± 6.5; P < 0.01) was greater in the cafeteria than in the control group. Whereas neither carcass conformation nor fatness were affected by the feeding system, the dressing percentage was slightly higher ( P>0.001) in the conventional than in the cafeteria system lambs.

The use of cafeteria systems for fattening lambs can improve the feed conversion efficiency and body growth rate over those achieved with conventional feeding systems, although the crude protein intake in these systems seems to be in excess of requirements.

Green biorefineries provide novel opportunities to use the green biomass efficiently and utilize the ecosystem services provided by grasslands more widely. The effects of the inclusion of fractionated grass silage solid fraction (pulp) on feed intake, rumen fermentation, diet digestion and milk production in dairy cows were investigated. Pulp was separated from grass silage using a screw press simulating a green biorefinery. Partial removal of liquid from forage increased DM concentration from 220 to 432 g/kg and NDF from 589 to 709 g/kg DM while CP decreased from 144 to 107 g/kg DM. A feeding trial using an incomplete changeover design with 24 Nordic Red cows and two 3-week periods was conducted. The pulp replaced grass silage in the diet at 0 (P0), 25 (P25) and 50 (P50) percentage of total forage, which was fed ad libitum with 13 kg of concentrate for all treatments. The forage DM intake was highest on P25 (14.1 kg/day) while P0 and P50 did not differ from each other (13.2 and 13.0 kg/day, respectively). There were no differences between the treatments in rumen pH or ammonia N, but the proportion of acetate increased with increasing pulp inclusion. The digestibility was measured using acid insoluble ash and indigestible NDF (iNDF) as internal markers. Neither of the markers detected differences in NDF digestibility, but according to iNDF, apparent total tract organic matter digestibility decreased with increasing pulp inclusion. The cows maintained milk production at P25, but it showed some decline at P50 (energy-corrected milk at P0 and P25 was 39.8 kg/day while for P50, it was 38.5 kg/day, P = 0.056) and the milk protein yield significantly declined with higher pulp inclusion. Simultaneously, the nitrogen use efficiency in milk production increased. It seems that the fibrous grass-based fraction from a biorefinery process has potential to be used as a feed for ruminants.

Computer simulations using parameters based on results from experiments showed that by chance a certain frequency of hypo-gammaglobulinaemia would always occur. This was due to variations in birth weight, concentration of immunoglobulin in the ingested colostrum, amount of colostrum offered, and age at first feeding. It was not necessarily associated with an absorption block as sometimes postulated. The probability of an individual getting hypogammaglobulinaemia can be minimized by early feeding of a large quantity of colostrum at the first feeding after birth.

The aim of the study was to investigate the influence of different energy levels during a 4-week lactation on the regulation of the metabolic hormones somatotropin (GH), prolactin, insulin and insulin-like growth factor-1 (IGF-1). A total of 21 crossbred sows (German Landrace × Duroc) were cannulated for daily blood collection from 3 weeks before parturition until 2 weeks after weaning and for weekly window sampling (every 20 min for 10 h). Nineteen sows were given 2·8 kg food during late gestation, 5·0 kg food during lactation and 2·8 kg food per day after weaning and two sows were given food at a restricted level (3·0 kg) during lactation. In the 19 sows, the different energy balance was induced by allocation of different numbers of sucking piglets to the respective sows. One group of sows suckled seven piglets and served as a control (C; no. = 7) and another group suckled 10 to 12 piglets and was energy deficient (D). After the study, the sows of the deficient group were, based on their litter weight gain from parturition until weaning, divided into low (D-L; no. = 6) or high (D-H; no. = 6) litter weight gain. The D-H sows lost more body weight during lactation than C and had lower glucose and higher nonesterified fatty acids levels before morning feeding. GH and prolactin increased around parturition and their secretory profiles during lactation were altered by the frequent sucking stimulus, whereby the access of the piglets to their dams was not controlled. During lactation, GH and prolactin were highest in D-H sows. The results suggest a possible role of not only GH but also of prolactin in nutrient partitioning to the mammary gland just before the start of lactation and for minimizing the adverse effects of a negative energy balance. Furthermore, insulin and IGF-1 increased around parturition in all sows. Insulin was higher before and after feeding and the highest levels were found in C and D-L sows. The regulation patterns of insulin and IGF-1 indicate that the lactating sow is able to mobilize enough energy from body reserves to prevent metabolic disorders, even during a period with deficient energy supply. This is contrary to the regulation in the dairy cow, where the negative energy balance is coupled with a severe glucose deficit during phases of high milk yield, which causes decreased levels of insulin and IGF-1. In the sow, the glucose intake with the food meets the glucose requirement for metabolic pathways also during a deficient lactational energy intake. Therefore, in sows IGF-1 can be stimulated by increased GH levels via the GH receptor in the liver during a state of nutritional energy deficiency and the fact that sows can compensate a deficient metabolic state much better than cows is also reflected in the respective endocrinology.

The use of the hormones, diethylstilboestrol, hexoestrol and testosterone propionate, as growth stimulants in beef cattle has been studied.

The subcutaneous implantation of 60 mg. stilboestrol into steers fattening in yards produced a highly significant increase in rate of gain (65%) and little difference in the yield and quality of the carcass. The implantation of 24 nig. or 36 mg. of diethylstilboestrol or 30 mg. hexoestrol into Friesian bullocks fattening on pasture produced highly significant increases in rates of gain (29%, 48% and 33% respectively). No significant difference was found in the rates of gain produced by these three treatments.

The oral administration of 10 mg. diethylstilboestrol per head per day for 168 days or the oral administration of 20 mg. rising to 40 mg. testosterone propionate per head per day for 154 days to dizygotic twin steers on equal feed intake significantly increased rate of gain by 15% and 21% respectively Feed efficiency as measured by the pounds of feed required to produce a pound of gain was significantly improved by both treatments. Carcass yield and carcass quality were not significantly affected by either treatment. No significant differences were found between the two treatments.

Examination of the thyroid and adrenal glands of treated and untreated steers revealed no consistent changes in size due to treatment. The gonadotrophin and thyrotrophin content of the anterior pituitary glands of treated and untreated cattle were compared using the male chick bioassay. The results showed that a lower gonadotrophin content was not a factor associated with the extra growth due to treatment, but in two out of three experiments there was some evidence that sex-hormone treatment leads to a mild hyper-thyroidism which, in turn, resulted in a decrease in the thyrotrophin content of the anterior pituitary gland. It was concluded that hyperactivity of the thyroid gland was probably more important in accounting for the extra growth than hyperactivity of the adrenal cortex.

An account is given of the conception rates (in terms of calves born) following artificial insemination of contemporary purebred and crossbred cattle derived from purebred Friesian, Ayrshire and Jersey stock in an experimental herd. First inseminations were given to 222 purebred and 495 crossbred females approaching first pregnancy; and to 165 purebred and 347 crossbred females approaching second pregnancy. Fitted values for conception rates showed no noteworthy differences for year, season, age of female, or breed of bull. Crossbred females, however, were about 10% more likely to conceive than purebreds. Purebred females mated to bulls of their own breed showed lower conception rates than those mated to bulls of another breed.

On the basis of the potential benefits to human health there is an increased interest in producing milk containing lower-saturated fatty acid (SFA) and higher unsaturated fatty acid (FA) concentrations, including cis-9 18:1 and cis-9, trans-11-conjugated linoleic acid (CLA). Twenty-four multiparous Holstein cows were used in two experiments according to a completely randomized block design, with 21-day periods to examine the effects of incremental replacement of prilled palm fat (PALM) with sunflower oil (SFO) in high-concentrate diets containing 30 g/kg dry matter (DM) of supplemental fat (Experiment 1) or increases in the forage-to-concentrate (F : C) ratio from 39 : 61 to 48 : 52 of diets containing 30 g/kg DM of SFO (Experiment 2) on milk production, digestibility and milk FA composition. Replacing PALM with SFO had no effect on DM intake, but tended to increase organic matter digestibility, yields of milk, protein and lactose, and decreased linearly milk fat content. Substituting SFO for PALM decreased linearly milk fat 8:0 to 16:0 and cis-9 16:1, and increased linearly 18:0, cis-9 18:1, trans-18:1 (Δ4 to 16), 18:2 and CLA concentrations. Increases in the F : C ratio of diets containing SFO had no effect on intake, yields of milk, milk protein or milk lactose, lowered milk protein content in a quadratic manner, and increased linearly NDF digestion and milk fat secretion. Replacing concentrates with forages in diets containing SFO increased milk fat 4:0 to 10:0 concentrations in a linear or quadratic manner, decreased linearly cis-9 16:1, trans-6 to -10 18:1, 18:2n-6, trans-7, cis-9 CLA, trans-9, cis-11 CLA and trans-10, cis-12 CLA, without altering milk fat 14:0 to 16:0, trans-11 18:1, cis-9, trans-11 CLA or 18:3n-3 concentrations. In conclusion, replacing prilled palm fat on with SFO in high-concentrate diets had no adverse effects on intake or milk production, other than decreasing milk fat content, but lowered milk fat medium-chain SFA and increased trans FA and polyunsaturated FA concentrations. Increases in the proportion of forage in diets containing SFO increased milk fat synthesis, elevated short-chain SFA and lowered trans FA concentrations, without altering milk polyunsaturated FA content. Changes in fat yield on high-concentrate diets containing SFO varied between experiments and individual animals, with decreases in milk fat secretion being associated with increases in milk fat trans-10 18:1, trans-10, cis-12 CLA and trans-9, cis-11 CLA concentrations.

Abstract Fifty intact male Barbarine lambs were used to assess the effects of restricted feeding and re-alimentation on carcass composition and fatty acid (FA) composition of intramuscular fat. Five lambs were slaughtered at the start of the trial; the remainder were randomly allocated to three groups. One group was offered only stubble grazing (low: L), another, also on stubble, received, indoors, an average of 80 g dry matter (DM) of soya-bean meal per day (medium: M); the third group was kept indoor and had free access to hay and 450 g of concentrate (high: H). At the end of this restriction period (70 days), five lambs per group were slaughtered. The 10 remaining animals in each group were divided into two groups receiving concentrate and hay ad libitum. The crude protein (CP) content of the concentrate was 160 and 210 g/kg DM in the two treatments, respectively. At the end of the trial all animals were slaughtered at 37·61 ± 2·05 kg live weight.

In the restriction period, bone tissue was similar in terms of mass for all diet treatments. The absolute weight of muscle and fat in carcasses was higher for unrestricted sheep (H) than for restricted ones, but L and M lambs had proportionately less fat and more muscle than those given food indoors. Intramuscular fat composition was similar for all the treatments. During this period, the carcass gain of M lambs had the highest proportion of muscle and the lowest fat concentration, which is the better composition. At the end of the compensating period, all carcasses contained the same quantity of bone and muscle, but unrestricted sheep had significantly more fat than compensating ones. So, carcasses of compensating animals contained relatively less fat (240 v. 310 g/kg) and more muscle (550 v. 500 g/kg) than unrestricted ones. The carcass gain of lambs with an earlier nutritional history on L had the highest muscle and the lowest fat concentration. The intramuscular lipid composition in terms of fatty acids showed differences between treatments. Unrestricted animals contained more C14: 0 and C16: 0 and compensating animals more C18: 2 and a higher proportion of polyunsaturated fatty acids (PUFA) and PUFA: saturated FA ratio. There were no significant differences associated with CP level during the re-alimentation period

The evolution of hyper-prolific pig breeds has led to a higher within-litter variation in birth weight and in BW gain during the nursery phase. Based on an algorithm developed in previous research, two populations from a pool of 368 clinically healthy piglets at 6 weeks of age were selected: a low (LP) and a high (HP) performing population and their development was monitored until the end of the nursery phase (10 weeks of age). To understand the cause of the variation in growth between these populations we characterized the LP and HP piglets in terms of body morphology, behaviour, voluntary feed intake, BW gain, and apparent total tract and ileal nutrient digestibility. Piglets were housed individually and were fed a highly digestible diet. At selection, 6 weeks of age, the BW of LP and HP piglets were 6.8±0.1 and 12.2±0.1 kg, respectively. Compared with the LP piglets the HP piglets grew faster (203 g/day), ate more (275 g/day) from 6 to 10 weeks of age and were heavier at 10 weeks (30.0 v. 18.8 kg, all P<0.01). Yet, the differences in average daily gain and average daily feed intake disappeared when compared per kg BW0.75. Assuming similar maintenance requirements per kg BW0.75 the efficiency of feed utilization above maintenance was 0.1 g/g lower for the LP piglets (P=0.09).The gain : feed ratio was similar for both groups. LP piglets tended to take more time to touch a novel object (P=0.10), and spent more time eating (P<0.05). At 10 weeks, LP piglets had a higher body length and head circumference relative to BW (P<0.01). Relative to BW, LP had a 21% higher small intestine weight; 36% longer length, and relative to average FI, the small intestinal weight was 4 g/kg higher (both P=<0.01). Apparent total tract and ileal dry matter, N and gross energy digestibility were similar between groups (P>0.10). We concluded that the low performance of the LP piglets was due to their inability to engage compensatory gain or compensatory feed intake as efficiency of nutrient utilization and feed intake per kg BW0.75 was unaffected. LP piglets tend to be more fearful towards novel objects. The morphological comparisons, increased body length and head circumference relative to BW imply that LP piglets have an increased priority for skeletal growth.

A study of the British Friesian Cattle Society's herdbook for 1961 showed that twin births were registered from 323 cows which had borne single calves the year before, and which had 2009 contemporaries of the same age calving single births in the same two seasons and in the same herds.

Least squares means of milk yield and fat percentage calculated from the truncated 305-day lactation showed that the twin mothers exceeded their contemporaries by 118±47 kg milk in lactations 2 days shorter. After correction for herd and year effects there was no difference between the twin birth lactation yield and the preceding single birth yield.

There was a reduction in fat percentage of 0±06% associated with the twin birth lactation.

The proportion of a sample of 194 twin mothers failing to calve again was 24±3% against 19±1% of the mothers of single calves, but no reasons for culling had been recorded.