Whole, dry barley treated with ammonia (A), whole, untreated barley (WU) or ground barley (G) were fed with hay and a little high protein concentrate to 7 to 11-month-old lambs. Most apparent digestibility coefficients were found to be 3 to 5 units higher in the diet with barley A than in diets with barley WU or G, the differences being significant. Calculation of the digestibility of barley by difference showed that the coefficients were 8 to 10 units higher in barley A than in barley WU or G as regards dry matter and organic matter. Digestion of crude fibre was better in both A and WU than in G. These differences were also significant.

Including dry feed materials (absorbents) with grass at ensiling has been shown to reduce effluent output and improve silage fermentation (Offer and Al-Rwidah, 1989) although the effects of this practice on animal performance have been somewhat variable (Ferris and Mayne, 1990; Jones, Jones and Moseley, 1990). However little is known about the fate of these absorbents during ensilage or the effects of ensiling upon their chemical composition. The aim of this investigation, which was part of a large scale dairy cow production study was to examine the nutrient recovery and compositional changes occurring with unmolassed sugar-beet pulp (SBP) when ensiled with grass at three levels of inclusion.

Freezing/thawing procedures induce enhanced reactive oxygen species (ROS) formation in mammalian sperm and these ROS may be a cause for the decrease in sperm function following cryopreservation. In the present study, we used a chemiluminescence method to detect ROS-induced damage in goat spermatozoa. Iron-induced luminescence of fresh and frozen/thawed sperm cells was assessed using a luminometer. It was shown that the freezing/thawing procedure had a significant effect on some luminescence parameters. Semen freezing significantly increased the values of integral, peak max, T.half (rise) and T.max (peak) parameters. A significant correlation was observed between the percentage of motile spermatozoa and integral, peak max and T.half (rise) parameters. In conclusion, the results of the present study indicate that measurement of induced luminescence can be an alternative, sensitive and relatively simple method for assessing the effect of cryopreservation on oxidative damage to spermatozoa.

Two groups of six male goats were used to assess the effects of rumen-protected supplements offish oil on intake, digestibility and nitrogen (N) balance. The animals were offered a diet consisting of forage and concentrate, the latter fraction supplemented with 0 (control) or lOOg/kg of rumen-protected fish oil supplement (PFO), containing a high proportion of the n-3 series (whole diet contained 0 or 60 g PFO per kg dry matter). No significant differences (P > 0.05) were found between the two groups concerning live-weight gain, food intake, digestibility of DM, organic matter, N, neutral-detergent fibre and energy. In contrast, there were differences (P < 0.05) regarding the digestibility of fat and of acid-detergent fibre, which were higher among the animals given the PFO diet. With respect to the individual fatty acids, we observed higher digestibility (P < 0.05) of C14:0, C16:0, C18:0 and C20:0 among the animals given the PFO diet. The digestibility of C14:0, C18:0 and C20:0 was found to be negative among the animals given the control diet. No significant differences (P > 0-05) were found regarding digestibility of total C18:1. In contrast, the coefficients for C18:2 (n-6) and C18:3 (n-3) were higher (P < 0.05) among the non-supplemented animals. The intake and faecal flow values of C18:0 suggest that the mono- and polyunsaturated fatty acids with 18 atoms of carbon may, in both cases, undergo partial hydrogenation, which would be greater among the control group. The utilization of C20:5 (n-3) and, especially, of C22 : 6 (n-3), which were consumed only by the animals given the PFO diet, was estimated at 1-000. The PFO diet also produced lower levels ofurinary-N excretion (P < 0.05), giving rise to higher N balances (P < 0.05).

The delayed onset of heat-induced panting (at 42°C) immediately following previous shearing and exposure to cold was studied in 54 Scottish Blackface and 53 Tasmanian Merino sheep.

In control sheep (not previously cold-exposed) thermal panting commenced in 15 min. In cold-treated sheep, when the cold was intensified stepwise from +26°C (+30cC being thermoneutral) down to −10°C, using 2-hr exposures, or lengthened from 2 hr to 16 hr at +8°C, the delay (block) to panting increased non-linearly from 40 to 70 min.

The minimum intensity of cold required to produce a block (26°C in Merinos, 22°C in Blackfaces) was similar to that inducing peripheral vasoconstriction. More intense vasoconstriction preceded longer blocks, but vasoconstriction sometimes occurred without a subsequent block.

Merinos were more sensitive than Blackfaces to the blocking effects of cold, and, once blocked, the effect in Merinos was less easily removed by re-warming.

The time taken for cancellation of the heat debt during heat stress could account for half the block. The remainder, a delay of about 30 min, was attributed to a specific inhibition of respiratory control in the central nervous system.

In a prospective 2-year study, milk progesterone and oestrone sulphate determinations were used to monitor and assess pregnancy in lactating cows. The testing was done centrally at a government regional veterinary establishment which was responsible for providing semen to the farms of the area and also had available specialist expertise in animal reproduction. Sample collection and dissemination of test results were achieved through the network of the artificial insemination service. This approach was preferred because it was considered ergonomic, cost-effective and reliable. Comparison of oestrus behavioural signs and progesterone on the day of insemination revealed that 7·8% (89/1133) of the animals tested had high progesterone levels. Single progesterone testing on day 21 post insemination was not satisfactory for pregnancy diagnosis as the positive predictive value was 83·0% (147/177). The combination of low progesterone on day 0 and high progesterone on day 21 improved the positive predictive value to 87·4% (235/269). Results from 400 samples taken 110 to 130 days post insemination from 53 animals revealed that cows with oestrone sulphate concentrations greater than 0·1 μg/l actually calved. This assay appears to be particularly suitable as a pregnancy confirmation test. A pilot field study implementing a programme of testing on days 0, 21 and 42 for progesterone and between days 110 to 130 for oestrone sulphate not only achieved almost absolute pregnancy predictive values but careful result analysis strongly indicated that the approach of systematic testing can also reveal the fertility profile of a given herd and help to identify potential causes of pregnancy failure from the period of the reproduction cycle in which they occur.

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.

These experiments investigated the efficacy and safety of the use of anabolic agents for finishing cull dairy cows over a two month period before slaughter. The safety of the treatment was assessed by measuring the residues of trenbolone acetate (TBA) and its metabolites in samples collected during the treatment period and at slaughter.

Body weight and gain data from eight studies conducted with weaner pigs to determine the relationship between stocking density and performance were used to evaluate the effect of various stocking densities on several factors which measure variation within pens. The initial weight of the pigs ranged from 5·7 to 8·3 kg and final weight ranged from 17·7 to 32·1 kg. There were 244 pens of pigs with floor space ranging from 0·11 to 0·28 m2 per pig. Average daily gain and body weight were depressed as stocking density increased. Natural logarithms of variance, coefficients of variation and ranges of average daily gains and body weights were not increased by stocking density. Body weights and daily gains appeared equally effective in measuring variance of weaner pigs housed at various densities. These results indicate that increasing stocking density within the range of densities tested does not cause a greater variation in body-weight gains.

On a fattening diet in which final molasses supplied from 68 to 76% of the metabolizable energy and napier grass some 10%, the treatments in a 2 × 2 × 3 factorial design were breed (Brahman or Brown Swiss × Brahman), source of supplementary protein (fish meal or poultry waste) and protein level (low, medium or high—replacing urea). Mean daily gains to 404 kg live weight were better for the crossbreds (0·89 compared with 0·77 kg), as was conversion rate in terms of Meal ME per kg gain (25·6 compared with 29·5); fish meal improved gains by 44% and conversion rate by 39% as compared with poultry waste when the two supplements were fed at levels designed to equate N intakes from this source. The superiority of the crossbreds was only apparent on the fish meal diets where they averaged 1·19 compared with 0·94 kg/day for the Brahmans. Daily N × 6·25 intakes decreased from 3·8 g/kg live weight on the low level of poultry waste to 2·9 on the high level due to low palatability of this material. On this treatment (poultry waste), daily gain (kg) was significantly related (b = 0·119±0·031; P<0·01) to N×6·25 intake (g) per unit live weight (kg). Commercial half carcass dissection showed the crossbreds to have significantly more edible meat, more bone and less e×cess fat than Brahmans. Protein source had no effect on carcass composition.

In trials 1 and 2, supplements of urea and cottonseed meal increased the protein content of the basal diets from 12·2 to 14·0–14·6%, but had no significant effects on growth rate or carcass characteristics. In trial 3 the effect of cottonseed meal on growth rate was almost significant but urea had less effect. In trial 4, the basal diet contained 11·0% protein; soya bean meal increased this to 13·1% and had an almost significant effect on growth rate. Lysine and lysine + urea had no effect.

Eight pregnant beef cows and four rumen-fistulated cows were given 1·67 kg barley dry matter per day and 5·1 kg chopped oat straw dry matter treated by one of four different methods. The straw treatments (given in a 4 × 4 Latin square design) were (A) nil, (B) sodium hydroxide (25 g/kg straw, dry matter basis), (C) a fully soluble liquid supplement containing urea, calcium, phosphorus, sodium, trace elements and vitamins (40 g/kg straw, dry matter basis), and (D) sodium hydroxide plus liquid supplement. In the absence of liquid supplement 0·3 kg per day of the straw dry matter was not consumed, and with the sodium hydroxide plus liquid supplement treatment the cows would have consumed more straw than was offered. Sodium hydroxide increased the digestibility of the straw organic matter from 0·46 to 0·50 (P <0·05), and this was further increased to 0·53 (P <0·01) for the combined sodium hydroxide plus liquid supplement treatment. The calculated metabolizable energy intakes from straw were increased from 31 (nil) t o 36 by either the sodium hydroxide or liquid supplement treatments (P <0·05) and to 41 by the combined treatments (P <0·001). Sodium hydroxide tended to increase the concentrations of n- and iso-butyric acids in the rumen liquor.

Twin Scottish Half bred × Suffolk lambs born to well-nourished ewes suffered no ill effects, in terms of growth rate or serum immunoglobulin levels, when deprived of colostrum for periods of up to 9 h after birth provided they received adequate colostrum after the deprivation period was completed.

Poor ewe nutrition during the last 8 weeks of pregnancy, when combined with 9-h periods of colostrum deprivation, adversely affected serum immunoglobulin levels and appeared to increase mortality.

The aim of this study was to estimate the parameters of the lactation curve of dairy cows in Scotland so as to improve the prediction of milk yield. The data used for deriving the parameters were ‘milk test’ yield values recorded by the Scottish Milk Records Association during a 2-year period. The data were grouped, according to lactation number, breed and area of Scotland, into 27 groups. The data pertaining to each group were then averaged so as to produce by regression analysis a curve for each calving week, lactation number and area. Areas and breeds were found to affect the shape of the lactation curves.

A major problem facing breeders interested in using bulls from other populations is that the foreign bull evaluations cannot be directly compared with the evaluations produced in the United Kingdom (UK). This is due to differences in the units of measurement, the base against which all bulls are compared and the method used to express the merit of the bulls. In order that selection is possible on an equal basis, it is necessary to be able to convert bull evaluations from the scale used in the country of export to that used in the importing country.

The general formula used to convert evaluations is of the form Y = a + bX where Y is the converted evaluation, X is the evaluation in the exporting country, a is the difference between the bases used for bull evaluations and b is the factor to take account of the differences in scale.

Salbutamol (albuterol) is a β-adrenergic agonist marketed as a racemic (50: 50) mixture of R- and S-enantiomers (rac-salbutamol). Since only R-salbutamol is pharmacologically active and S-salbutamol has a longer half-life in humans, we examined R-salbutamol as a performance enhancer and repartitioning agent in domestic chickens. The effects of feeding diets containing R-salbutamol (5, 10 and 15 mg/kg diet) and rac-salbutamol (10 mg/kg diet) from day 21 to 42 post hatching on growth performance, carcass characteristics and tissue concentrations of R- and S-salbutamol in male and female broilers were compared with a control diet. R-salbutamol in the diet lowered the weight gains in both sexes, but the magnitude of reduction was greater in males as indicated by a significant R-salbutamol ✕ gender interaction. R-salbutamol also lowered food intake and improved food conversion ratios in both sexes. The relative weights of breast muscle and leg muscle were significantly increased and the relative weight of the fat pad was significantly decreased in birds of both sexes given diets containing R-salbutamol. Carcass protein content increased and carcass fat content decreased but the differences were not statistically significant. A significant dose-response effect was observed for tissue concentrations of R-salbutamol in all tissues, except the fat. Performance and carcass parameters in chickens given the 5 mg/kg R-salbutamol diet were similar to those given the 10 mg/kg rac-salbutamol diet, but tissue concentrations of R-salbutamol were lower. Chickens given the 10 mg/ kg rac-salbutamol diet had higher tissue concentrations of salbutamol than chickens given the 10 mg/kg R-salbutamol diet and higher concentrations of S-salbutamol than R-salbutamol in liver and leg muscle. Overall, these results demonstrate that R-salbutamol is an effective repartitioning agent in broiler chickens.

Feeding different groups of 1 year-old prepubertal female rainbow trout for 0, 4, 8 or 12 months on either high (1.0% body weight day-1) or low (0.4%) rations produced significant changes in fecundity, total egg volume and in the percentages of fish which spawned. Fish fed high ration for the first 4 or 8 months of the year-long cycle had up to 56% higher fecundities even after weight influences had been partitioned by covariance analysis. Groups of fish fed high ration for the first 4 months of the cycle included the highest percentages of spawning fish. By optimising feeding regimes commercial hatcheries could produce up to 3x more eggs from existing stocks.

The influence of pre-slaughter nutrition on the potency of foetal serum in cell culture was studied. Ewes carrying late-gestation foetuses (120-day gestation) were either fasted for 66 h (F), fasted for 66 h but drenched with Ketol, a propylene glycol preparation, (5 × 120 ml doses; FK), given food ad libitum (A), or given food ad libitum and drenched with Ketol (5 × 120 ml doses; AK). Following slaughter foetal blood was collected for the determination of potency in cell culture using industry-standard cell culture bioassays: cloning efficiency, plating efficiency and a 96 h cell proliferation assay. Foetal serum insulin-like growth factor (IGF) concentrations were also measured. Pre-slaughter fasting or drenching with Ketol had no effect on the potency of foetal serum in any of the cell culture bioassays. Fasting significantly lowered foetal plasma IGF-1 levels (F < 0·01). Foetal IGF-2 levels were unaffected by fasting or drenching with Ketol.

Mutants of Bacillus subtilis can be developed to overproduce Val in vitro. It was hypothesized that addition of Bacillus subtilis mutants to pig diets can be a strategy to supply the animal with Val. The objective was to investigate the effect of Bacillus subtilis mutants on growth performance and blood amino acid (AA) concentrations when fed to piglets. Experiment 1 included 18 pigs (15.0±1.1 kg) fed one of three diets containing either 0.63 or 0.69 standardized ileal digestible (SID) Val : Lys, or 0.63 SID Val : Lys supplemented with a Bacillus subtilis mutant (mutant 1). Blood samples were obtained 0.5 h before feeding and at 1, 2, 3, 4, 5 and 6 h after feeding and analyzed for AAs. In Experiment 2, 80 piglets (9.1±1.1 kg) were fed one of four diets containing 0.63 or 0.67 SID Val : Lys, or 0.63 SID Val : Lys supplemented with another Bacillus subtilis mutant (mutant 2) or its parent wild type. Average daily feed intake, daily weight gain and feed conversion ratio were measured on days 7, 14 and 21. On day 17, blood samples were taken and analyzed for AAs. On days 24 to 26, six pigs from each dietary treatment were fitted with a permanent jugular vein catheter, and blood samples were taken for AA analysis 0.5 h before feeding and at 1, 2, 3, 4, 5 and 6 h after feeding. In experiment 1, Bacillus subtilis mutant 1 tended (P<0.10) to increase the plasma levels of Val at 2 and 3 h post-feeding, but this was not confirmed in Experiment 2. In Experiment 2, Bacillus subtilis mutant 2 and the wild type did not result in a growth performance different from the negative and positive controls. In conclusion, results obtained with the mutant strains of Bacillus subtilis were not better than results obtained with the wild-type strain, and for both strains, the results were not different than the negative control.