A review of work reported in the literature was used to present quantitative descriptions of energy dispositioning in the growing pig. These are detailed in the text, which points to preferred values, as well as to anomalies and lacunae. The review was prepared with the objective of allowing from its content the inclusive and quantitative modelling of energy requirement. Requirement is approached as the sum of the component factors; maintenance, protein retention and lipid retention. Conventional expressions of maintenance requirement, as some function of pig mass, were found unconvincing in their variety of expression of coefficients and exponents. The review concluded that maintenance is properly related to protein turn-over, and thereby requires at least to include elements of concomitant protein metabolic activity. It was also judged that maintenance costs might be farm-specific. The energy requirements for activity, gaseous losses and disease were identified as important, but unsatisfactory in their quantification. Exploration of the energy costs of uncomfortable ambient temperatures suggested that whilst the responses of the pig are open to sophisticated and relatively exact calculation, the description of comfort remained inexact. The efficiency of retention of lipid by direct incorporation was high and may comprise a substantial proportion of the dietary lipid supply. There was little evidence of variation in the efficiency of utilization of metabolizable energy from carbohydrate for lipid retention. The linear-plateau paradigm for protein retention was adopted. The efficiency of utilization of energy for protein retention measured by a variety of approaches was found to be highly variable, prone to error and the literature confused. It was concluded that the efficiency of use of metabolizable energy for protein retention would be a function of at least: (a) the absorbed substrate being metabolized for the synthesis of body protein, (b) the rate of total protein tissue turn-over associated with the retention of newly accreted protein and not already accounted in the estimate of maintenance, (c) the mass of protein tissue involved in turn-over, and (d) the degree of maturity attained, and any influence maturity may have upon the rate of turn-over of total body protein. Algorithms for energy requirement are presented based upon protein turn-over and these appear to have some consistency with empirical findings.

The aims of this study were to examine population structure and inbreeding trend in six dog breeds in Finland and to assess the inbreeding depression for hip and elbow dysplasia. Data consisted of 289 569 dogs, of which 36 924 dogs also had a record for hip and/or elbow dysplasia screening. From the early 1980s onwards, inbreeding trends were decreasing in the Golden Retriever, the Labrador Retriever, the Rough Collie and the Rottweiler, probably as a result of importations of dogs, and somewhat increasing in the Finnish Hound and the German Shepherd. When analysed per generation, observed mean inbreeding coefficients were higher than the expected ones in each breed, indicating that breeders have not actively avoided inbreeding. As a class effect, the inbreeding level was significant only for hip dysplasia in the Labrador Retriever and the German Shepherd breeds. As a regression, inbreeding level of a dog had only a minor effect on both of the dysplasias. Hip dysplasia in the Labrador Retriever appeared to be more influenced by longer term aggregation of homozygosity (long-term inbreeding) in animals than by shorter-term inbreeding. When analysed from two data sets with a minimum of five and two ancestral generations for each dog in the data, a statistically significant association between hip dysplasia and inbreeding for the Labrador Retriever could be detected only in the former data set.

A Bayesian threshold-liability model with Markov chain Monte Carlo techniques was used to infer genetic parameters for clinical mastitis records collected on Holstein-Friesian cows by one of the United Kingdom’s national recording schemes. Four data sets were created to investigate the effect of data sampling methods on genetic parameter estimates for first and multi-lactation cows, separately. The data sets were: (1) cows with complete first lactations only (8671 cows); (2) all cows, with first lactations whether complete or incomplete (10 967 cows); (3) cows with complete multi-lactations (32 948 records); and (4) all cows with multiple lactations whether complete or incomplete (44 268 records). A Gaussian mixed linear model with sire effects was adopted for liability. Explanatory variables included in the model varied for each data set. Analyses were conducted using Gibbs sampling and estimates were on the liability scale. Posterior means of heritability for clinical mastitis were higher for first lactations (0·11 and 0·10 for data sets 1 and 2, respectively) than for multiple lactations (0·09 and 0·07, for data sets 3 and 4, respectively). For multiple lactations, estimates of permanent environmental variance were higher for complete than incomplete lactations. Repeatability was 0·21 and 0·17 for data sets 3 and 4, respectively. This suggests the existence of effects, other than additive genetic effects, on susceptibility to mastitis that are common to all lactations. In first or multi-lactation data sets, heritability was proportionately 0·10 to 0·19 lower for data sets with all records (in which case the models had days in milk as a covariate) than for data with only complete lactation records (models without days in milk as a covariate). This suggests an effect of data sampling on genetic parameter estimates. The regression of liability on days in milk differed from zero, indicating that the probability of mastitis is higher for longer lactations, as expected. Results also indicated that a regression on days in milk should be included in a model for genetic evaluation of sires for mastitis resistance based on records in progress.

A breeding experiment in Coopworth sheep where selection was applied to backfat depth was evaluated after 14 years (1981-94). There were three self-replacing lines, two selected for increased or decreased subcutaneous fat depth, and an unselected control (average size = 51 ewes per line per year). Reproductive traits, ewe body weight and ewe fleece weight were monitored in each line as potential correlated responses. In the last 4 years studied, the fat (F), control (C) and lean (L) lines differed significantly in the proportion of ewes lambing (0·87, 0·93, 0·94 respectively), litter size at birth (1·64, 1·83 and 1·89), and lamb survival up to weaning, unadjusted for birth rank and sex (0·88, 0·81 and 0·74). The overall reproductive trait, lambs weaned per ewe joined (1·22, 1·33 and 1·26), did not differ significantly among lines. From pre-mating weights of ewes present in 1993 or 1994, means for mature ewes by line were 60·1, 62·4 and 63·3 kg, respectively (P < 0·01). Means for weight at scanning time (7 months of age) by line, as a proportion of mature weight were: 0·533, 0·561 and 0·559, respectively (P < 0·05). There were also significant line differences in ewe fleece weights, with the 1993 and 1994 data averaging 3·93, 4·05 and 4·27 kg respectively (P < 0·01). For weight of lamb weaned per ewe weaning at least one lamb, the L line had a 0·09 higher mean proportionally than the F line (P < 0·05), but for a composite trait which was a weighted combination of weight of lambs weaned and ewe fleece weight per ewe joined (with or without allowance for different ewe live weights), the L line was no longer significantly different from the F line. Repeatabilities and single-record heritabilities were also estimated for various ewe traits. The implications are that lean-lamb selection would be associated with only small changes in net reproduction, ewe fleece weight and live weight, but larger differences would be expected from selection in the opposite direction.

The effect of double-muscling (DM) genotype (double-muscling, mh/mh; heterozygous, mh/+; normal, +/+) of Belgian Blue (BB) young bulls on the intramuscular fatty acid composition, in particular conjugated linoleic acid (CLA) and polyunsaturated fatty acids (PUFA) was examined in five different muscles. The relative fatty acid composition showed only minor differences between muscles within genotypes. However, the DM genotype had a large effect on both the intramuscular total fatty acid content and on the relative fatty acid composition. Across muscles, the mh/mh animals had a lower total fatty acid content compared with the +/+animals (907 v: 2656 mg/100 g muscle; P < 0·01) and a higher PUFA proportion in total fatty acids (27·5 v 11·3 g/100 g total fatty acids; P < 0001), resulting in a higher PUFA/saturated fatty acid ratio (0·55 v 0·18; P < 0·01) and a lower n-6/n-3 ratio (5·34 v. 6·17; P < 0·01). The heterozygous genotype was intermediate between the two homozygous genotypes. The relative CLA content was similar in the mh/mh and +/+ genotypes and approximated 0·4 to 0·5 g/100 g total fatty acids. From the data it is further suggested that differences in the metabolism of the n-3 and n-6 fatty acids could exist between DM genotypes.

It is hypothesized that the fat colour of steers raised at pasture can be manipulated by altering animal growth patterns using the effects of post-pubertal surgical castration and oestradiol treatment. The fat colour of 151 steers of three genotypes of beef cattle, castrated at approximately 9 months or 18 months of age and treated, or not treated, with oestradiol after castration, was studied.

Surgical castration of beef cattle at both 9 months of age or 18 months of age caused no readily apparent animal welfare problems. The combined effects of early or late castration and oestradiol treatment produced varying growth patterns with early castrates exposed to two post-castration episodes of growth associated with carotene-rich forage and late castrates only one such episode of growth.

Late castrates and early castrates treated with oestradiol had a less yellow fat than early castrates not treated with oestradiol. The proportion of carcasses with commercially significant yellowness in the fat was decreased by either late castration or by oestradiol treatment. There was no effect of genotype on fat colour.

Glucocorticoids and their tissue receptors are involved in many metabolic and developmental processes. Until now only two short fragments with a total length of 200 amino acids were known from the glucocorticoid receptor of the pig. Therefore we sequenced the main part (2.1 kb) of the porcine receptor. In addition, we subcloned a cDNA fragment of this sequence coding for 135 aa of the modulatory region in a pET expression vector. The protein fragment was expressed in E. coli as a his-tag fusion protein. In the SDS-PAGE, the crude E. coli extracts showed an enrichment of a 15 kDa protein which corresponds to the estimated molecular weight for the receptor fragment.

After lysis and Ni-NTA affinity chromatography under denaturing conditions the protein was further purified either by dialysis (native protein) or by SDS-PAGE (linearized form). Both forms were emulsified together in adjuvant and used for rabbit immunization.

The resulting antibodies were characterized by western blot analysis, immunoprecipitation, and additionally by immunohistochemistry. Western blot analysis confirmed the binding of the denatured protein by the antiserum and revealed a high binding affinity. Immunoprecipitation demonstrated that both the occupied and unoccupied forms of the receptor are detected. The specificity of the antiserum for pGCR was additionally demonstrated by immunohistochemistry.

Studies in rodents and primates strongly indicate that prenatal stress affects the survival, behaviour and physiology of the offspring. Stressful stimuli during gestation may have a direct or hormone mediated effect on the development of stress systems in the foetal organism, resulting in an altered coping during stressful situations. The present study was conducted to elucidate prenatal stress effects in domestic pigs on the responses of the hypothalamicpituitary- adrenocortical (HPA) axis and the sympatho-adrenomedullary (SAM) system as well as on morbidity, mortality and growth of the offspring. Pregnant sows were subjected to a restraint stress for five minutes daily during the last five weeks of gestation. Endocrine reactions of the piglets were tested at 3, 7, 21 and 35 days of age using an immobilization test and an ACTH challenge test. Prenatally stressed piglets showed lower basal plasma cortisol and increased corticosteroid binding globulin (CBG) concentrations at 3 days of age, indicating decreased free cortisol concentrations after birth. Cortisol levels after ACTH stimulation and catecholamine levels after immobilization were not affected by the stress treatment of the sows. Piglets from stressed sows tended to have lower noradrenaline : adrenaline ratios at three days of age compared with the control piglets. In addition, stressed sows tended to have lower litter weights after birth. The morbidity and mortality during the suckling period was higher in the prenatally stressed litters, as shown by a higher frequency of diseased and perished piglets per litter. We suppose that prenatal stress during late gestation in pigs alters the development of the HPA system and impairs the vitality of the offspring.

A 3-week feeding trial using 300 1-day-old male broiler chicks was conducted to evaluate the effects of adding three levels of a microbial phytase (Finnfeed phytase; 250, 500 and 1000 U per kg diet) to a maize-soya-bean-meal diet containing 3·0 g/kg non-phytate phosphorus and 8·0 g/kg calcium. A diet containing 4·0 g/kg non-phytate phosphorus and 9·0 g/kg calcium served as the positive control. The responses were evaluated in terms of broiler performance, toe ash contents, ileal phytate degradation, ileal digestibility of nitrogen, amino acids, phosphorus, starch and fat, apparent metabolizable energy, apparent ileal digestible energy, and apparent retention of phosphorus and nitrogen. The addition of 500 U phytase per kg diet to the phosphorus-deficient maize-soya-bean-meal diet improved the performance and toe ash contents of broilers to equal those given the positive control diet. Ileal phytate degradation data provided direct evidence to the efficacy of phytase in hydrolysing the phytic acid. Addition of 500 U phytase per kg to the maize-soya-bean-meal diet which contained 3·0 g phytate-phosphorus per kg resulted in more than doubling of phytate degradation from 0·218 to 0·481. Supplemental phytase improved ileal digestibility of nitrogen, amino acids, starch and lipids, with these improvements being eventually reflected in enhancements in ileal digestible energy and apparent metabolizable energy.

To investigate the utilization of different carbohydrate sources and the possible protein-sparing effects of carbohydrates for grouper (Epinephelus malabaricus), six isoeneregtic purified diets were prepared. Three dietary protein levels (500, 460, 420 g/kg) were achieved by substitution with three levels (143, 195, 246 g/kg) and two sources (glucose and starch) of dietary carbohydrate. Each of the six diets was given to triplicate groups of grouper in a recirculating rearing system for 8 weeks. In the glucose group, weight gain of fish decreased with increasing dietary glucose and decreasing protein content. In the starch group, weight gain of fish given the 500 g/kg protein diet was higher (P < 0 ·05) than fish given the 460 and 420 g/kg protein diets. At each of the dietary protein levels weight gain of the glucose-group fish and the starch-group fish were similar (P > 0·05). At the 500 g/kg dietary protein level body lipid content of the starch-group fish was higher than that of glucose-group fish. At 500 and 460 g/kg dietary protein levels, fish given starch diets had higher hepatic hexokinase activity than fish given the glucose diets. These results suggest that, at the levels studies, the utilization of starch and glucose by grouper is similar. Decreasing the dietary protein level from 460 g/kg to 420 g/kg by increasing the starch content in the diet from 195 g/kg to 246 g/kg did not reduce (P > 0·05) weight gain and food efficiency, suggesting that starch could spare some protein when the dietary protein level is low.

Young male red deer follow a seasonal growth pattern that can be shifted by altering the photoperiod they experience. An increase in photoperiod to 16 h of light per day (16L : 8D) during winter advances the onset of rapid growth and high food intake that normally commences in spring. These changes are associated with increased growth hormone (GH) and insulin-like growth factor-1 (IGF-1) secretion. The GH/IGF-1 axis is acutely sensitive to the level of nutrition and the relative rôles of photoperiod and nutrition in determining the spring IGF-1 rise is unknown. The present experiment set out to examine this by exposing two groups of deer (no. = 8 per group) to a photoperiod shift during their 1st year of life (16L : 8D from 2 June), designed to cause accelerated growth and increased food intake after approximately 7 weeks. However, after 6 weeks the food intake (pellets containing 11 MJ metabolizable energy and 160 g crude protein per kg dry matter (DM)) of one group (LDRES) was clamped, thereby preventing the intake component of the response. The intake of the other group (LDAL) remained ad libitum for a further 12 weeks until 6 October, when the experiment concluded.

During the first 6 weeks of 16L : 8D, growth rate (118 (s.e. 15·4) g/day) and food intake (1·37 (s.e. 0·031) kg DM per head per day) did not differ between the groups. Food intake following the clamp in LDRES averaged 1·40 (s.e. 0·015) kg per head per day. The intake of LDAL increased 2 weeks after the clamp and thereafter was higher than LDRES (P < 0·001). Food intake of LDAL averaged 2·13 (s.e. 0·051) kg during the nutritional clamp period. Growth rates increased in both groups during the first 3 weeks of the clamp, averaging 237 (s.e. 25·0) g/day, then growth slowed in LDRES and live weights diverged. Growth rates until the end of the experiment (147 (s.e.23·0) g/ day v. 299 (s.e. 12·5) g/day, P < 0·001) and mean live weight over the last 5 weeks of the experiment were lower (P < 0·05) in LDRES than LDAL, weights reaching 88·3 (s.e. 1·86) kg and 97·9 (s.e. 2·74) kg respectively on the final sampling date. Metatarsal bone length grew more in LDAL than in LDRES (3·1 v. 2·2 cm, s.e.d. = 0·23, P < 0·01). Prior to the nutritional clamp, mean plasma prolactin and IGF-1 concentrations increased at 3 and 6 weeks after 16L : 8D respectively, in both groups. Prolactin concentrations were lower in LDRES than LDAL on two occasions, at weeks 3 and 7 after the onset of the nutritional clamp, and IGF-1 concentrations were lower in LDRES than LDAL (676 v. 872 ng/ml, s.e.d. = 73·8, P < 0·05) over the last 7 weeks of sampling.

In summary, a photoperiodically driven increase in IGF-1 occurred even when the usual associated increase in food intake was prevented. This indicates that the seasonal IGF-1 rise in red deer is not a consequence of the increased food intake, although the latter appears necessary to maintain elevated IGF-1 concentrations. The rise in IGF-1 may therefore be considered as a component of the photoperiodically entrained seasonal drive to grow, and the increase in food intake a response to satisfy the increased energy demand.

A comparison of in vitro microbial activity was made between inocula from faeces of adult and unweaned pigs, using a range of carbohydrate-rich substrates. The substrates tested were classified into groups (fibre-rich, grains, gums, pectin, saccharides, storage carbohydrates, and miscellaneous). Proximate and fibre analyses were determined for all substrates tested. Fermentation kinetics were measured according to the cumulative gas production technique. End-point products such as gas, volatile fatty acids and ammonia were also determined. The faeces from the adult pigs (ATF) were collected from four castrated finisher pigs (Dutch Landrace × Great Yorkshire). These were offered a diet based on highly digestible maize starch and fish meal, so as to be as free as possible of fermentable carbohydrates. The unweaned piglet faeces were collected from 19 unweaned piglets (male and female) which were 27 to 30 days old. The parameters were tested for significance by an analysis of variance using the Tukey's studentized range test of multiple comparisons. There were significant differences in the fermentation patterns both due to source of substrate and inoculum. It would appear that the metabolic activity of the microflora does differ significantly between adult and weanling pigs, though this varied for the different carbohydrates tested. Suggestions are made as to how to select potential carbohydrate ingredients for an in vivo experiment, based on their in vitro fermentation characteristics.

This study was designed to investigate the size distribution of bovine steroidogenic luteal cells throughout pregnancy. Corpora lutea collected from three different stages of pregnancy were used. Luteal tissue was dissociated into single-cell suspension by enzyme treatments. Cells were stained for 3β-hydroxysteroid dehydrogenase (HSD) activity a marker for steroidogenic cells. The steroidogenic cells covered a wide spectrum of size ranging from 10 to 60 µm in diameter. There was a significant increase in mean cell diameter (P > 0·05) as pregnancy progressed. Mean diameter of 3β-HSD positive cells increased from 17·03 (s.e. 1·3) µm in the corpus luteum of early pregnancy to 33·38 (s.e. 2·4) µm in the corpus luteum of advanced pregnancy. The ratio of large (>22 µm in diameter) to small (10 to 22 µm in diameter) luteal cells was 0·32 : 1·0 in the early pregnancy, with the 10 to 22 µm cell size class predominant. However, the ratio of large to small luteal cells was increased to 6·49 : 1·0 µm as pregnancy advanced and 23 to 42 µm cell sizes become predominant. It is likely that small luteal cells develop into large cells as gestation progresses. Development of pregnancy is associated with an increase in size of steroidogenic luteal cells.

A series of laboratory and animal studies examined the use of chemical and biological agents to enhance the digestibility of Rhodes grass (grass) cut at 60 (young) and 100 (mature) days of regrowth and ensiled as big round bales. The treatments included an untreated control (C), a microbial inoculant (I), NaOH, CaO and NaOH plus inoculant (NaOH + I). Inoculant was grown anaerobically, using a starter culture of rumen fluid from cattle given Rhodes grass. Treatments C, I, NaOH, NaOH + I, were offered separately to twelve dairy heifers, in a 3 ✕ 4 randomized complete block design, repeated twice for each grass silage. C and I had substantial mould growth, compared with no visible mould in NaOH or NaOH + I. CaO treatment was effective in preventing mould growth, but had little effect on the chemical composition and in sacco digestibility of mature grass silage. NaOH reduced NDF content and increased in sacco digestibility (P < 0·05) but not the in vivo digestibility (P > 0·05) of both mature- and young-grass silage. The effects of other treatments on nutritive value were non-significant at both stages of maturity. NaOH increased the intake of mature-grass silage by 24-26% (P < 0·05), but had little effect on the intake of young-grass silage (P > 0·05). Treatment I consistently reduced grass silage intake (P < 0·05) for young-grass silage. The findings of these studies show that treating mature Rhodes grass with NaOH will improve its nutritive value and reduce mould growth in conserved herbage. However none of the treatments in this study had any consistently positive effects on the in vivo nutritive value or storage quality of young-grass silage.

The effects of space allowance during transportation and duration of a mid-journey lairage period on measurements of stress, injury, dehydration, food restriction and rest in young calves were assessed during and after transport. Groups of calves were transported for two 9-h journeys (at a space allowance of either 0·375 or 0·475 m2 per calf) separated by a mid-journey lairage period of either 1 or 12 h. Non-transported calves were offered milk replacer and drinking water either at the usual times or only at the same times as the transported calves.

During transport, transported calves spent significantly less time lying down and had a greater plasma cortisol concentration than control calves. Under the driving conditions used, increased space allowance was not associated with greater injury or loss of stability. The duration of the mid-journey lairage was not an important factor; the shorter lairage time, giving the calves sufficient time to receive milk replacer but little opportunity to rest, had no major detrimental effects on the variables used to assess welfare. Although there was little evidence that transport affected immunological variables, there was some evidence that it adversely affected the health of the calves post transport.