Three experiments were carried out to investigate the anabolic effects of androstenedione administered at various levels to female and castrated male lambs in one experiment and to entire and castrated male calves in two other experiments. Significant increases in growth were not effected in normally fed animals but a sex × dose level interaction was detected in female lambs. Under normal husbandry conditions androstenedione appears to have little application in meat production.

Milk consumption was estimated for crossbred suckled calves from birth to weaning during 2 years. Breed groups utilized were Aberdeen Angus (A) and Charolais (C) sires on Fl Angus-Hereford (and their reciprocals) dams in the 1st year and in the 2nd year, sires A and Nelore (Bos indicus) (N) were used on the same type of dam. The weigh-suckle-weigh technique was employed twice a day to estimate milk consumption on a weekly basis. Estimations were adjusted by least-squares for the effects of genetic group, week of estimation, and their interaction, with sex of calf and calf and cow weights in the week of estimation as covariables. Then a non-lineal regression equation of the form: y = b0Wb1e -b2b2W was fitted for each individual, where y = milk consumption and W = week of estimation. Curves for A and C were very close in their shape, but with a greater consumption (P < 0·01) for C. For the 2nd year, there were differences among A and N both in the shape of the curve and in consumption at the peak of lactation (P < 0·01). Differences in time to peak lactation were also found: for A calves, it was week 9, for C calves week 10 and for N calves week 3·8. The N group showed a sharper decline in persistency than the other groups, suggesting different patterns in milk consumption.

Countries, which import a significant amount of semen, embryos and animals, are faced with the problem of how properly to evaluate the animals in the national evaluation system when information on the foreign parents is generally missing. Additional problems arise when the foreign parents obtain an evaluation, usually on the basis of progeny, in the country of import with the result that there are two published evaluations for the animals in question. This paper presents a post-iterative method of incorporating foreign information into home country evaluations. The foreign information is initially converted to the same scale and base as in the home country using procedures recommended by the International Bull Evaluation Service. The method consists essentially of calculating a combined evaluation for animals with home and foreign information as a weighted average of yield deviations, parent averages and progeny contributions from the foreign and home countries. The combined evaluations are used to adjust the evaluations of progeny on the basis of formulae derived from the usual mixed model equations. The same principles were used to combine reliabilities from the respective home and foreign reliabilities. The results from the application of the method to the United Kingdom (UK) Holstein Friesian population are presented. There was re-ranking of both bulls and cows, especially foreign bulls with few UK daughters.

The effects of a dietary supplement with calcium salts of fatty acids and methionine hydroxy analogue on reproductive performance, blood metabolites, milk production, milk composition, body weight and body condition score was studied in lactating dairy cows. Autumn-calving, Holstein-Friesian cows (no. = 162) were assigned 1 week post calving to one of two diets: (1) unsupplemented maize-silage-based complete diet while housed before turn-out to perennial ryegrass pasture and (2) the same diet with 400 g per cow per day of a supplement with calcium salts of long-chain fatty acids and methionine hydroxy analogue (Megalac Plus, Volac Ltd). Eleven cows were removed from the study following randomization for reasons not related to the experiment leaving 151 cows on dietary treatments. The diets were offered until the end of the 18-week breeding period. Cows receiving supplement had higher milk yield and milk lactose production and lower milk protein and milk fat proportion (P < 0·05). Body weight and body condition scores were not different between treatments in the first 20 weeks of lactation (P > 0·05). Overall reproductive performance was not different between dietary treatments (P > 0·05). However, first lactation animals (no. = 33) receiving the dietary lipid and methionine supplement tended to have increased conception rates to first and second service (P < 0·09) which resulted in a shorter calving-to-conception interval in those animals (P < 0·06). Services per conception (P < 0·08), services per cow served (P < 0·05) and services per conception for pregnant cows (P < 0·05) in first lactation animals was reduced in the supplemented group. Although plasma cholesterol concentrations were increased following lipid and methionine supplementation (P < 0·01), plasma progesterone concentrations on day 5 and day 8 after artificial insemination were not different between dietary treatments (P > 0·05). In conclusion, a dietary supplement of calcium salts of fatty acids and methionine hydroxy analogue increased milk yield, milk lactose production and blood cholesterol concentration but did not improve reproductive performance, except in first lactation cows.

Thirty six individually-fed pigs were used in a within-litter comparison of the 6 treatments of a 3 × 2 factorial experiment. The pigs were about 9 weeks old at the start and were slaughtered as their individual weights reached about 200 lb.

Three types of basal diet were given with and without a supplement of CuSO4.5H2O included at 0·1% (250 p.p.m. added Cu).The diets were based on (1) barley and fish meal, with 17% crude protein for pigs up to 103 lb. live-weight and 15·4 % from then on, (2) maize and soya (extracted soya bean meal), with about the same levels of protein and (3) maize and soya, but with only 13·4% crude protein for pigs up to 103 lb. and 11·9% for pigs of 103 lb. to 200 lb. Daily feed allowances were determined from a fixed scale based on live-weight.

Pigs given the high-protein maize-soya diets grew more rapidly, required less feed per lb. gain and had fatter carcasses than those given the barley-fish meal diets. This was probably because of the higher TDN content of the maize-soya mixture.

Pigs given the low-protein maize-soya diets grew less rapidly, required more feed per lb. gain and had fatter carcasses with smaller ‘eye’ muscles than those receiving the high-protein maize-soya diets, these being the usual effects of an inadequate supply of total protein or of an essential amino acid.

CuSO4.5H2O4 added as 0·1% of each of the three types of diet improved growth rate before 103 lb. live-weight but had no consistent effect on feed conversion efficiency. Between 103 lb. and slaughter the copper sulphate did not affect performance on the barley-fish meal or high-protein maize-soya diet, but in the low-protein maize-soya diet it reduced feed conversion efficiency and rate of gain by 5%. Although this interaction was not statistically significant it agrees with an observation made in Florida and warrants further investigation.

Genetic and phenotypic parameters were estimated for farmed red deer on eight farms distributed throughout the United Kingdom. Genetic parameters were estimated using restricted maximum likelihood (REML) analysis. Heritabilities for date of calving were low on seven of the eight farms (< 0–05), while repeatabilities were low to moderate (0·06 to 0·37). Heritabilities of all weights tended to be moderate to high on most farms (0·31 to 0·49; 0·22 to 0·89; 0·33 to 0·48; 0·37 to 0·45 and 0·37 to 0·90 for birth weight, weaning weight, mid-winter weight, turn-out weight and other weights respectively). The exception was farm 8 for which heritability estimates were very low (<0·08). This is attributed to inbreeding effects on this farm. Phenotypic and genetic correlations between post-weaning traits tended to be high, indicating selection at any stage of growth will be expected to lead to an increased growth at the other stages. Animals whose bloodlines originated in the forests of Eastern Europe (Yugoslavia, Hungary, Germany) were heavier at all stages indicating their usefulness as ‘terminal sire’ breeds. Hinds of mainland ‘European’ parentage also tended to calve earlier.

It has been demonstrated with Australian breeds and conditions that active immunization of ewes against androstenedione can induce increases in lambing rate of 20 or more lambs per 100 ewes mated (Cox, Wilson, Scaramuzzi, Hoskinson, George and Bindon, 1982; Geldard and Scaramuzzi, 1983). More recent work (Geldard, 1985) involving active immunization against androstenedione (Fecundin®, Coopers Animal Health, UK) has shown that similar results can also be achieved with some United Kingdom breeds. However, the successful application of this product in practice requires a knowledge of the patterns of reproductive response that can be obtained with a much wider range of genotypes and production systems.

Fifty entire male pigs between 7 and 28 days and 50 entire male pigs between 28 and 56 days of age' were given basal diets containing peanut meal as the protein supplement. These diets contained 4·5 to 6·1 g threonine per kg and were supplemented with graded additions of synthetic L-threonine.

It was found that the amount of threonine required for maximum performance and nitrogen retention was 6·6 g/kg dry matter (DM) between 7 and 28 days of age and 5·4 g/kg DM between 28 and 56 days of age. These values were calculated to correspond to 0·43 and 0·36 g threonine per MJ digestible energy.

The concentration of threonine in the blood plasma did not give a clear indication of the threonine requirement of the pigs.

‘ANIMAL – An International Journal of Animal Bioscience’ is the central element in a new and exciting collaborative venture between the European Federation for Animal Science (EAAP), Institut National de la Recherche Agronomique (INRA), and British Society of Animal Science (BSAS). It merges three high-quality and successful journals (Animal Science, Animal Research and Reproduction, Nutrition, Development) into a single forward-looking publication that will reduce fragmentation in the sector, improve synergies and, we hope, act as a catalyst for integrating process-level and systems science in the animal biosciences.

Feed conversion ratio (FCR) in grow-finishing pigs is one of the most important determinants of pig farm profitability and production efficiency. In its simplest form, FCR represents the amount of feed used per unit weight gain of the pig. Yet, this approach entails various limitations hampering its practical applicability such as availability of accurate data and large variation in ways to adapt FCR values for different starting and end weight as well as mortality rates. Various stakeholders are using their own formulas to determine FCR creating a ‘definition nonconformity’ when comparing FCRs among farms. This study aimed to optimize the calculation of FCR through the use of participatory qualitative research. A multidisciplinary research group of 9 persons (animal scientists, veterinarians and agricultural economists) and a consulting group of 31 stakeholders (representing the Flemish primary sector, feed industry, pharma, genetic companies, large retailers, academia and policy institutions) were involved. The decision problem analysis started with a literature review, followed by 25 in-depth interviews and their analyses (NVivo 11™). This led to an additional literature review and the formation of focus (expert) groups that helped to formulate preliminary FCR formulas. Revision rounds between the research team and the stakeholders further fine-tuned the formulas with the final result being two distinct complimentary formulas that are fit for purpose. Both refer to carcass gain per kg feed intake (plain (CGF) and standardized (CGFstandardized)). The first formula (CGF), namely ${{{\it{number \, delivered \, pigs}} \times {\it{average \, warm \, carcass \, weight}} - {\it{number \, stocked \, piglets}} \times {\it{average \, piglet \, weight}} \times {\it{piglet \, carcass \, yield}}} \over {{\it{feed \, consumption}}}}$ is an objective representation of the animals’ performance. The second formula (CGFstandardized) was developed for farm benchmarking, incorporating a seven-step standardization process that corrects for mortality and ‘standardizes’ for a fixed (yet fictive) live weight trajectory of 25 to 115 kg. This second formula allows to compare farms (or batches of fattening pigs) with different weight trajectories and different mortality rates. A webtool was designed to ease this standardization process (https://varkensloket.be/tools/CGF).

The aim of the present study was to evaluate the prediction ability of models that cope with longevity phenotypic expression as uncensored and censored in Nellore cattle. Longevity was defined as the difference between the dates of last weaned calf and cow birth. There were information of 77 353 females, being 61 097 cows with uncensored phenotypic information and 16 256 cows with censored records. These data were analyzed considering three different models: (1) Gaussian linear model (LM), in which only uncensored records were considered; and two models that consider both uncensored and censored records: (2) Censored Gaussian linear model (CLM); and (3) Weibull frailty hazard model (WM). For the model prediction ability comparisons, the data set was randomly divided into training and validation sets, containing 80% and 20% of the records, respectively. There were considered 10 repetitions applying the following restrictions: (a) at least three animals per contemporary group in the training set; and (b) sires with more than 10 progenies with uncensored records (352 sires) should have daughters in the training and validation sets. The variance components estimated using the whole data set in each model were used as true values in the prediction of breeding values of the animals in the training set. The WM model showed the best prediction ability, providing the lowest χ2 average and the highest number of sets in which a model had the smallest value of χ2 statistics. The CLM and LM models showed prediction abilities 2.6% and 3.7% less efficient than WM, respectively. In addition, the accuracies of sire breeding values for LM and CLM were lower than those obtained for WM. The percentages of bulls in common, considering only 10% of sires with the highest breeding values, were around 75% and 54%, respectively, between LM–CLM and LM–WM models, considering all sires, and 75% between LM–CLM and LM–WM, when only sires with more than 10 progenies with uncensored records were taken into account. These results are indicative of reranking of animals in terms of genetic merit between LM, CLM and WM. The model in which censored records of longevity were excluded from the analysis showed the lowest prediction ability. The WM provides the best predictive performance, therefore this model would be recommended to perform genetic evaluation of longevity in this population.

Boars have a decisive impact on the progress in pig production, however, there is no recent information about the optimal growth parameters during the rearing period for modern breed later used in artificial insemination (AI) stations. Therefore, the objective of the research was to conduct semen parameter and conception rate analyses on the basis of growth rate and meat content assessments made during the rearing of AI boars of different genotypes. The study was carried out between 2010 and 2014 and included 184 boars in five breed combinations: 46 Polish Large White, 50 Polish Landrace, 27 Pietrain, 36 Duroc×Pietrain and 25 Hampshire×Pietrain. Boars were qualified by daily gains and meat content assessment (between 170 and 210 days of life). A total number of 38 272 ejaculates were examined (semen volume (ml), spermatozoa concentration (×106 ml−1), total number of spermatozoa (×109) and number of insemination doses from one ejaculate (n)). The fertility was determined by the conception rate (%). Semen volume, spermatozoa concentration and conception rate (P<0.01), followed by the total number of spermatozoa and insemination doses (P<0.05) were characterized by the highest variability in relation to breed of boars. The effect of daily gains was reported for spermatozoa concentration, number of insemination doses, conception rate (all P<0.01) and total number of spermatozoa (P<0.05). The peak of growth for spermatozoa concentration, total number of spermatozoa, insemination doses and conception rate was achieved for 800 to 850 g gains. Meat content affected semen volume, number of insemination doses and conception rate (P<0.05). Rearing boars while maintaining daily gains at the 800 to 850 g level and 62.5% to 65% meat content helps AI stations to increase the efficiency and economic profitability, and the number of insemination doses to increase by up to 300 doses/boar within a year. The analyses of growth parameters may help increase the efficiency and economic viability of AI stations.

The dietary inclusion of feed additives to improve the carcass characteristics of the final product is of great importance for the pork production chain. The aim of our study was to evaluate the effects of the association of ractopamine (RAC) and conjugated linoleic acid (CLA) on the performance traits of finishing pigs during the last 26 days prior to slaughter. In total, 810 commercial hybrid barrows were used. Animals were distributed among treatments according to a randomised block design in a 3 × 3 factorial arrangement, with three RAC levels (0, 5 or 10 ppm) and three CLA levels (0, 0.3 or 0.6%). Pigs fed the diet with 5 ppm RAC had higher average daily feed intake (ADFI) (2.83 kg; P < 0.05) when compared with those fed 10 ppm RAC and the control diet (2.75 and 2.74 kg, respectively). Lower ADFI values (P < 0.01) were observed with the diets containing CLA compared with the control diet with no CLA (2.73 and 2.75 v. 2.85 kg/day, respectively). The average daily weight gain of pigs fed 5 and 10 ppm RAC was +148 and +173 g/dayhigher (P < 0.001), respectively, than those fed the control diet. Dietary RAC levels influenced (P < 0.001) feed conversion ratio (FCR), which was reduced as RAC levels increased, with the pigs fed 10, 5 and 0 ppm RAC presenting FCR values of 2.57, 2.71 and 3.05, respectively. FCR also improved (P < 0.05) with the inclusion of 0.6% CLA relative to the control diet (2.70 v. 2.84, respectively). There was a significant interaction between CLA × RAC levels (P < 0.01) for final BW, loin eye area (LEA) (P < 0.05) and backfat thickness (BT) (P < 0.05). The treatments containing 10 ppm RAC + 0.6% or 0.3% CLA increased LEA and reduced BT. In conclusion, the level of 10 ppm inclusion of RAC increased the overall performance parameters of pigs and therefore improved production efficiency. The combined use of RAC and CLA promoted a lower feed conversion ratio as well as better quantitative carcass traits, as demonstrated by the higher LEA and lower BT. The dietary inclusion of CLA at 0.3% improved feed efficiency, however, without affecting LEA or BT yields.

This experiment evaluated different strategies for allocating first-cut grass silages to dry dairy cows that had low body-condition score (BCS) at drying off. A total of 48 moderately yielding Holstein-Friesian cows were used, receiving one of three dietary treatments in the dry period and a single lactation diet based on a flat-rate of concentrates and grass silage ad libitum. Throughout the dry period, one group received a low-digestibility silage (harvested 15 June 1998; LL; metabolisable energy (ME) = 10.3 MJ/kg dry matter (DM)) and a second group received a high-digestibility silage (harvested 9 May 1998, HH; ME = 11.7 MJ/kg DM). A third strategy (LH) offered the low-digestibility silage in the early dry period and the high-digestibility silage in the final 3 weeks before calving. The silages had very different crude protein concentrations (144 and 201 g/kg DM) and intakes were widely divergent (10.1 v. 13.5 kg DM/day) across the dry period. No concentrates were fed during the dry period. Silage quality had a very large effect on liveweight change, with treatment means of 0.32 and 1.75 kg/day for LL and HH, respectively. BCS changes followed a similar pattern, though no cows became over-conditioned and blood metabolites were within normal ranges. Increased silage digestibility in the late dry period led to a substantial increase in milk fat concentration and a smaller increase in milk protein concentration, the latter confined to the first full week of lactation. Depression of milk fat appears related to low blood glucose when dry cows in low body condition are fed at a low level. The LH strategy avoided the tendency for lower milk yields and fat concentration that resulted from feeding the low-digestibility silage until calving. This strategy also avoided the higher calf weights that resulted from feeding the high-digestibility silage in the early dry period.

In a 2×2 factorial design, 12 Thai Native and 12 Holstein bulls were fed ad libitum a total mixed ration (20 : 80; roughage : concentrate) with whole cottonseed (WCS) or sunflower seed (SFS) as oilseed sources. The rations contained 7% crude fat and were fed for 90 days. Plasma was taken at three times during the experiment, and at slaughter the longissimus dorsi and subcutaneous fat were sampled for fatty acid analysis. Ration did not affect rumen fermentation parameters. The plasma fatty acid profile was not affected by ration. In subcutaneous fat, a ration×breed interaction for the saturated fatty acid (SFA) and c9t11 CLA proportions was observed, resulting from larger differences between the rations in Thai Native compared with Holstein bulls. The WCS ration resulted in higher proportions of SFA and lower proportions of monounsaturated fatty acids and c9,t11 CLA compared with the SFS ration (P<0.01). In the intramuscular fat, the WCS ration was also associated with a lower c9t11 CLA proportion (P<0.01) and higher SFA proportion (P<0.05). The intramuscular proportion of polyunsaturated acids was higher and the proportion of SFA was lower in Thai Native compared with Holstein bulls (P<0.05), irrespective of ration.

Molecular cloning, tissue distribution and ontogenetic regulation of sodium/proton exchanger isoform 2 (NHE-2) mRNA expression were evaluated in the pig small intestine during postnatal development. The 2872-bp porcine full cDNA sequence of the NHE-2 (EF672046) cloned in this study showed 80% and 70% homology with known human and mouse gene sequence, respectively. Hydrophobic prediction suggests 13 putative membrane-spanning domains within porcine NHE-2. The porcine NHE-2 mRNA was detected in the brain, liver, kidney, heart, lung, small intestine and muscle. The small intestine had the highest NHE-2 mRNA abundance and the brain, lung and liver had the lowest NHE-2 mRNA abundance (P < 0.05). Along the longitudinal axis, the duodenum had the highest NHE-2 mRNA abundance and the ileum and colon had the lowest NHE-2 mRNA abundance (P < 0.05). The NHE-2 mRNA level was increased from day 1 to day 26 in the duodenum (P < 0.05) and dropped dramatically on day 30 (P < 0.05). There is no difference between day 1 and day 7 (P > 0.05). After day 30, the NHE-2 mRNA level remained the same except on day 90 (P > 0.05). The mRNA expression of NHE-2 was not only differentially regulated by age but also differentially distributed along the small intestine of piglets at early stages and growing stages of life, which may contribute to changes in NHE activity.

I am not setting up to be an expert on the raising of store cattle in general and I propose now to tell you something of my own experiences from the Hill Farmers', angle and to air my favourite theory that a tremendous increase in beef production (as well as in other commodities) could come from the upland grazings of this island.

The question I asked myself ,right away, back in 1930, was would cattle live on the hills during the winter? All that I ever saw on the hills were just the local small.herds in summer on the rough grazings on what we call in Wales, Ffridd land, in Scotland, and North of England, Inbye land; enclosed by a fence or a stone wall, near the homestead.

Three experiments (EXP) were conducted to determine the role of insulin-like growth factor-I (IGF-I) in the control of growth hormone (GH) and LH secretion. In EXP I, prepuberal gilts, 65 ± 6 kg body weight and 140 days of age received intracerebroventricular (ICV) injections of saline (n = 4), 25 μg (n = 4) or 75 μg (n = 4) IGF-I and jugular blood samples were collected. In EXP II, anterior pituitary cells in culture collected from 150-day-old prepuberal gilts (n = 6) were challenged with 0.1, 10 or 1000 nM [Ala15]-h growth hormone-releasing hormone-(1-29)NH2 (GHRH), or 0.01, 0.1, 1, 10, 30 nM IGF-I individually or in combinations with 1000 nM GHRH. Secreted GH was measured at 4 and 24 h after treatment. In EXP III, anterior pituitary cells in culture collected from 150-day-old barrows (n = 5) were challenged with 10, 100 or 1000 nM gonadotropin-releasing hormone (GnRH) or 0.01, 0.1, 1, 10, 30 nM IGF-I individually or in combinations with 100 nM GnRH. Secreted LH was measured at 4 h after treatment. In EXP I, serum GH and LH concentrations were unaffected by ICV IGF-I treatment. In EXP II, relative to control all doses of GHRH increased (P < 0.01) GH secretion. Only 1, 10, 30 nM IGF-I enhanced (P < 0.02) basal GH secretion at 4 h, whereas by 24 h all doses except for 30 nM IGF-I suppressed (P < 0.02) basal GH secretion compared to control wells. All doses of IGF-I in combination with 1000 nM GHRH increased (P < 0.04) the GH response to GHRH compared to GHRH alone at 4 h, whereas by 24 h all doses of IGF-I suppressed (P < 0.04) the GH response to GHRH. In EXP III, all doses of IGF-I increased (P < 0.01) basal LH levels while the LH response to GnRH was unaffected by IGF-I (P > 0.1). In conclusion, under these experimental conditions the results suggest that the pituitary is the putative site for IGF-I modulation of GH and LH secretion. Further examination of the role of IGF-I on GH and LH secretion is needed to understand the inhibitory and stimulatory action of IGF-I on GH and LH secretion.

The aim of this study was to test for the existence of causative genetic variation affecting body composition traits within or adjacent to the porcine insulin-like growth factor 2 (IGF2) gene beyond the known IGF2-intron3-G3072A mutation. A focussed quantitative trait loci analysis using four microsatellite markers within the telomeric region of porcine chromosome 2p was conducted in a large resource population comprising 2741 F2 offspring. The analysis of two subsets of animals that were alternatively homozygous for the in3G3072A mutation provides evidence for additional genetic variation significantly contributing to the overall quantitative trait nucleotide variance within our population.