With the increase in the use of wet feeding systems, there has been a controversy over the optimum water to feed ratio to be used in these systems. Braude et al., (1967) showed that the feed conversion ratio was 20% higher for wet fed pigs compared to dry fed pigs. However, Forbes et al., (1968) found no significant difference in daily gain between wet and dry fed pigs.

Gill et al., (1987) conducted an experiment to investigate the effects of different water to feed ratios on the performance of growing pigs provided with an additional water supply. They showed that liveweight gain and feed conversion significantly improved (p < 0.05) as the water to feed ratio of the liquid feed was increased from 2:1 to 3.5:1.

The objective of this experiment was to investigate whether water to feed ratio effects digestibility, digestible energy and nitrogen retention.

It is known that uptake of di- and tripeptides by distinct peptide transport systems is an important biological process by which amino acids are absorbed from the gastrointestinal tract (Rubino et al 1971; Webb and Bergman, 1991). However, until recently it was generally accepted that absorbed peptides had to be completely hydrolysed in to free amino acids within the enterocyte (Krzysik and Adibi, 1977) prior to their transport into the circulation. Nevertheless, it has been suggested that, in ruminant species at least, a substantial proportion of the total amino acid uptake from the gastrointestinal tract may be in the form of peptides (Webb, 1990; Seal and Parker, 1991; Webb and Bergman, 1991) and that a large part of this absorption may occur across the stomach region (i.e. rumen and omasum) (Webb, 1990). Consequently, the present study was designed to assess the uptake of amino acids in the form of low molecular weight peptides across the gastrointestinal tract of growing lambs.

In Bangladesh, locally produced fishmeal is available as a protein source of lactating cows but there is a need to find an alternative concentrate such as a legume browse which can be grown on small farms. An experiment has been carried out to assess the effect on performance of partly replacing fishmeal with fresh foliage from Sesbania sesban.

Milk quotas have resulted in a reduction in dairy cow numbers between 1983 and 1987 which represents a loss of almost 250,000 calves for beef rearing. Increasing slaughter weights is one way to make up for some of the consequent shortfall in beef production. However slaughter weights will not increase unless it is profitable to the producer.

MLC investigations are showing that differences in performance within a group of finishing cattle means that there is extra profit in keeping faster growers longer than average. Table 1 shows slaughter weights of a group of Charolais cross male suckled calves at different ranges of daily gain. Optimised slaughter weights for each sub-group and the extra gross margin after interest which should have accrued if they had been sold at the optimised weights are also given. Within the group the fastest growing bulls should have been kept longest and would have shown the biggest increase in margins.

The data were collected from seven dairy farms in India on Sahiwal × Friesian crosses over a period of 30 years (1937–1966). There were nine distinct genetic groups (grades); Sahiwal, 1/8, 1/4, 3/8, 1/2, 5/8, 3/4 and 7/8 Friesian and Indian Friesians (animals having 15/16 or more Friesian blood).

Least-square analysis of variance was run to examine the effects of grades, farms, periods, seasons, and breed of sire on body weights at birth, 19 weeks, 12 months and 3 years. The effects due to grades, farms and periods were significant for all the traits. The effects due to season and breed of sire were significant for all traits except for weight at 3 years.

The least-square constants showed that, with increase in Friesian inheritance, birth weight increased considerably, while the increase in body weights at 19 weeks, 12 months and 3 years was only marked up to the 1/2-Friesian group.

There was no evidence from three experiments with 60, 600 and 400 Welsh Mountain ewes producing mostly single lambs that housing, tested as an extreme form of shelter, was of benefit to reproductive performance. This was so when the ewes were kept indoors throughout the whole of the winter, or only at mating or during late pregnancy. Also, housing during early lactation did not lead to improved lamb growth rate.

Housing at lambing was associated in two experiments with reductions in perinatal lamb mortality from 5·1% to 3·1% and from 7·2% to 5·9%, though the differences were not significant.

Flushing had no significant effect on conception rate or reproductive performance, but the data were in accord with the view that when applied to ewes in moderately thin condition it leads to reduced barrenness and some increase in twinning.

Lactation records of Jersey cattle on Jersey Island are recorded within National Milk Records of England and Wales (NMR). Since it is a closed breed population, it is not possible to amalgamate these data with Jerseys recorded in the United Kingdom (UK). Presently genetic evaluations of Jersey Island bulls are carried out using heifer records with a modification of the model used in the UK to account for the smaller herd sizes. Cows are not evaluated.

The objective of this study was to analyse Jersey Island data in order to estimate genetic parameters and establish genetic trends after evaluating all bulls and cows using an Individual Animal Model (LAM).

Heart rate, ventilation measurements and gas exchange were studied in seven Hinterwaelder (Bos taurus) (494 (s.e. 16) kg) and five zebu (Bos indicusj oxen (516 (s.e. 60) kg), while the animals were standing, walking and pulling different loads. During standing, the heart rate, respiration rate, ventilation volume per min, total carbon dioxide production, total oxygen consumption and oxygen consumption per heart beat were lower in the zebu group than in the Hinterwaelder group (P < 0·05). The higher values for the Hinterwaelder were probably due to their higher metabolic rate, because of their younger age, higher level of feeding and better quality diet. The adaptation of gas exchange to higher work loads was achieved mainly by higher ventilation volumes. The composition of the expired air changed minimally. At similar levels of draught power output, the total energy expenditure minus energy expenditure of walking of the zebu oxen was lower than that of the Hinterwaelder oxen (P < 0·02). On the other hand at similar levels of heat production, the heart rate and ventilation volume per min did not differ significantly between the two breeds (P > 0·05). In spite of the differences in environment, feeding level and draught efficiency, the physiological adaptations made by the two breeds in response to work were similar.

Moving onto silage aftermath is an integral part of the 1.2.3 grazing system. In this system two thirds of the grass area are conserved for first cut silage while the other third is grazed. Between first and second silage cuts the silage aftermath is grazed while the original grazing area is closed for silage. After the second silage cut the whole area is grazed. In this trial the contribution of silage aftermath to the system was investigated by comparing the intake and performance of young cattle moved onto aftermath in raid-season with that of similar animals grazing the same sward continuously.

Thirty-two Hereford x Friesian and thirty-two Limousin x Friesian steers (mean liveweight 193 ± 16.8 kg) were allocated to either Treatment C, grazed continuously on the same sward throughout the experiment or Treatment S where the animals were turned onto silage aftermath in mid-season. Treatments were replicated twice and balanced for breed and liveweight of animals.

Active immunisation against androstenedione (Fecundin, Coopers Animal Health) increases ovulation and lambing rates. A study undertaken during the 1984-85 breeding season in randomly cycling ewes mated during October and November showed an increase in lambing rate of 24 lambs/100 ewes mated amongst ewes treated with Fecundin (Vipond, Keeling and Hunter, 1986). Fecundin increased the Incidence of triplet and quad births, suggesting that the greater benefit from the product would be derived in a situation where management could ensure the survival of additional lambs. The early lambing flock is such a case. Ovulation rates tend to be lower than later on in the breeding season, so fewer triplets might be expected amongst treated ewes. Management tends to be of a high standard, and the value of the early finished lamb is high.

This study was designed to test whether Mucuna pruriens, a natural source of l-dihydroxyphenylalanine (l-DOPA, a dopamine precursor) feeding, can influence development and reproductive conditions in the high food value bird, Japanese quail, Coturnix coturnix japonica. Experiments were performed in both male and female Japanese quail. One-week-old quail chicks were divided into three groups of 36 birds each. Group I was provided with normal diet and served as control. Group II was provided with food mixed with l-DOPA (50 mg/15 g food) and Group III was provided with food mixed with M. pruriens seed powder (480 g/kg food). At the age of 3 weeks (when birds were sexually distinguished) Group I was divided into two sub-groups IA (male) and IB (female) of six birds each. Similarly, Groups II and III were sub-divided into IIA (male), IIB (female) and IIIA (male), IIIB (female), respectively, of six birds each. Observations were made up to the age of 5 weeks. Male experimental groups (IIA and IIIA) showed significantly increased testicular activity, cloacal gland volume, body weight (BW), plasma testosterone and LH level in comparison to control (IA). Similarly female experimental groups (IIB and IIIB) showed significantly greater weight of reproductive organs (uterus, ovary, oviduct and ovarian follicle), BW, egg weight and size and number of follicles. On the other hand, plasma prolactin level was significantly low in comparison to control (IB). Results suggest that M. pruriens is a rich natural source of l-DOPA and the development and reproduction in Japanese quail might be associated with the dopaminergic system of the brain.

Golden hamsters of one common laboratory strain had a high incidence of hydrocephalus internus. When a severity score of hydrocephalus was used, a major autosomal recessive locus could be identified. However, when a binary score (hydrocephalus, no hydrocephalus) was used, no such major locus could be detected and results of test matings were not consistent with Mendelian inheritance. Golden hamsters with severe forms of hydrocephalus had a dorsally compressed and ventrally intact hippocampus. Implications for the behavior and well-being of affected hamsters are unknown but researchers using this strain should be aware of the likely presence of hydrocephalus.

Livestock food was contaminated with starling excrement by placing caged starlings (Sturnus vulgaris) over livestock food troughs and feeders, and allowing starling excreta to fall on food for periods ranging from 30 to 56 consecutive days. Several levels of contamination were tested by varying the number of caged starlings over troughs, from 1 to 18 birds per m2 of trough area. During the winters of 1979 and 1980, four trials were conducted involving 78 pigs of both sexes, 24 steers and 18 male calves. No significant differences were observed in daily rate of weight gain or efficiency of food conversion (food offered per unit gain), suggesting that neither cattle nor pigs appeared to be adversely affected by exposure to starling excreta in their food. Food rejection observed during these trials appeared to be a negligible problem overall. Although limited disease incidence did occur, it did not appear to be associated with food contamination.

The N fraction of fresh grasses, silages and hays is generally considered to be extensively degraded in the rumen. However published N degradability values for each type of material vary over quite a wide range. This may, at least in part, be due to an effect of the stage of growth of the harvested material since with increasing maturity there are marked changes in chemical composition and botanical features. Accordingly the ruminal N degradability characteristics of perennial ryegrass, harvested at different stages of growth and conserved as hay or silage, were determined using the polyester bag procedure.

Crops of young primary growth (C1), first regrowth (C2) second regrowth (C3) and mature primary growth (C4) were harvested from a field of perennial ryegrass c.v.S23. For each crop the fresh grass was stored frozen, conserved as field-cured hay and conserved by ensiling in laboratory silos either directly or after wilting and in both cases with or without formic acid addition (3l/tonne). The silos were opened after 90d and the silages subsequendy stored frozen.

An experiment was made to examine the effects of food intake and an orally active progestagen on plasma steroid concentrations and subsequent reproductive performance of multiparous sows. Thirty-five multiparous Landrace × Large White sows were assigned to one of four treatments immediately after parturition. Treatment H-AT sows were offered a high level of food intake throughout lactation: 3·5 kg of a diet containing 160 g/kg dry matter (DM) of crude protein and 13 MJ digestible energy per kg DM given twice daily. Treatment H+AT sows were offered the same food intake as H-AT sows and in addition they were given 20 mglday of allyl trenbolone (AT) mixed with the morning feed. Treatment L-AT sows were given 1·5 kg of the same diet offered twice daily during lactation and treatment L+AT sows were also offered this lower level of food intake and given AT. The respective levels of food intake were offered to sows from the 1st day of lactation onwards until weaning at 21 days post partum. Litter weights at weaning were influenced significantly by feeding level (P < 0·001) and also by AT administration (P <0·05). Sows on the high level of feeding had the heaviest litters and food-restricted sows had the lightest litters. AT treatment depressed litter weight at weaning. There was no effect of food level or AT on the plasma concentrations of progesterone or oestrogens during lactation. There was a highly significant (P <0·001) difference in mean plasma oestrogen concentration between high (H-AT and H+AT) and low (L-AT and L+AT) fed groups during early pregnancy in the subsequent cycle. Sows given a combination of high energy in lactation and AT (H+AT) exhibited shorter intervals from weaning to oestrus than both groups of food-restricted (L-AT and L+AT) sows fP <0·01) but treatment had no significant effect on either the farrowing rate or on the subsequent litter size. It is concluded that despite significant changes in the live weight and condition of sows and changes in steroid hormone concentrations due to food intake and the administration of allyl trenbolone, there were no significant effects on reproductive performance.

The objective was to study the effect of rumen-escape starch and coarseness of ingredients in pelleted concentrates on performance, carcass quality and rumen wall characteristics in rosé veal calf production. Two alternative concentrates (Coarse and Slow) were compared with a traditional (Control) concentrate. Control was based on finely ground ingredients, whereas in Coarse, the same ingredients were coarsely ground resulting in a mean particle size before pelleting of 1.5 in Coarse and 0.6 mm in Control. Slow compared with Control and Coarse contained finely ground sorghum and corn instead of barley and wheat which increased the amount of rumen-escape starch to 59 compared with 22 g/kg in Control and Coarse. All concentrates had the same total starch (362 g/kg), NDF (168 g/kg), CP (154 g/kg) and DE (15.5 MJ/kg DM) content and a pellet diameter of 3.5 to 4 mm. Use of an ‘indicator of starch digestibility’ method gave a value of 98.6% for Control and Coarse and 91.1% for Slow (P < 0.001). A total of 57 Holstein bull calves (n = 19 per treatment) were offered one of the three concentrates ad libitum from weaning ( $$$2\frac{1}{2}$$$ months of age) to slaughter (<10 months of age). Concentrate intake was recorded individually. Barley straw was available ad libitum but intake was not recorded. Average daily gain (1.43 kg/day), concentrate conversion efficiency (3.7 kg DM concentrate/kg gain), LW at slaughter (386 kg), carcass weight (194 kg) and EUROP conformation (3.9) were not affected by type of concentrate (P > 0.05). Papillae length and shape evaluated in atrium ruminis and the cranial part of the ventral rumen sac at slaughter were not affected by type of concentrate (P > 0.05). Rumen wall characteristics showed degrees of plaque formation (i.e., papillary aggregation), hyperaemia and necrotic areas in all treatment groups, but with no general difference between type of concentrate (P > 0.05). Incidence of liver abscesses (LAs, 16%) was not affected by type of concentrate (P > 0.05). There were no differences in performance or rumen wall characteristics between liver-abscessed and non-abscessed calves. The results show a high level of production performance with the three types of pelleted concentrates and indicates that neither the more coarse ingredients nor the additional rumen-escape starch tested, when fed ad libitum, could improve rumen wall characteristics or reduce LAs of rosé veal calves.

The results are given from trials which were designed to demonstrate the effects of feeding antibiotics and a tranquiliser to beef cattle. In Trial 1 the feeding of 80 mg. aureomycin daily produced no significant effect. In Trial 2 the feeding of neither 2·5 mg. hydroxyzine nor 80 mg. terramycin nor the two combined produced any significant effect except to depress the level of intake of dry-matter over the whole trial period. This reduction in drymatter intake did not lead to an increase in efficiency of conversion (lb. dry-matter intake per lb. live-weight gain). In trial 2 the tranquiliser tetrahydrozoline was unsuccessfully used at the beginning of the trial in an attempt to reduce the loss in live-weight suffered when the animals were tied up.

This study was conducted to examine the relationship between soya-bean agglutinin and cholecystokinin in stimulating pancreatic enzyme synthesis in rats. In experiment 1, 30 rats were given daily gastric infusions of 0, 3·5, 7·0, 10·5, or 14·0 mg of soya-bean agglutinin (no.=6) for 14 days. Compared with the control group, soya-bean agglutinin reduced weight gains, enhanced absolute and relative dry pancreatic weights, elevated serum cholecystokinin levels, and stimulated cholecystokinin mRNA expression in the intestine (P<0·001). Pancreatic nucleic acid composition and the pancreatic activities of the enzymes amylase, trypsin and chymotrypsin all increased in response to increasing levels of soya-bean agglutinin (P<0·001). In experiment 2, duodenal cells obtained from two rats were incubated at 37°C with either saline, 100 μg/ml soya-bean agglutinin, or a mixture of 100 μg/ml soya-bean agglutinin and 10 mmol/m of the L-type, calcium channel antagonist verapamil. Soya-bean agglutinin stimulated cholecystokinin mRNA expression and cholecystokinin release from small intestinal mucosal cells, and the effect was attenuated by verapamil. In experiment 3, pancreatic acinar cells, obtained from three rats, were incubated at 37 °C with either saline, or cholecystokinin (100 fmol/ml) and soya-bean agglutinin (1000 fmol/ml), either alone or in combination. Amylase, trypsin, and chymotrypsin activities from both culture media and acini cells were stimulated by both the soya-bean agglutinin and the cholecystokinin treatments. Enzyme activities, when the two factors were incubated in combination, were intermediate to those obtained when the factors were incubated alone. This suggesting that soya-bean agglutinin may depress the action of cholecystokinin on pancreatic enzymatic activities. In summary, soya-bean agglutinin appears to stimulate pancreatic enzyme synthesis both directly and also through a cholecystokinin-mediated pathway.

1. The data relating to 16 multi-location trials involving several varieties of egg-laying chickens per trial have been analysed to obtain estimates of variety × location (genotype-environment) interactions for rearing and laying mortality, hen-month and hen-housed egg production and 32-week egg weight. Significant interactions were found in about a third of the trials for all five traits though in only two cases did the interaction variance account for more than 20% of the total variance.

2. Genetic correlations for varieties between locations have been calculated as 0·49 for rearing mortality, 0·50 for laying mortality, 0·72 for hen-month production, 0·76 for hen-housed production and 0·91 for egg weight. These are in close agreement with previous published estimates.

3. The between-and within-variety components of variance have been calculated for each trait on each location separately. The regressions within trials and pooled values of the components on the mean level of all varieties on the location have been calculated. For hen-month production the pooled regres-son of the within-variety component on mean was negative, whilst for all other traits the pooled regressions were positive. The pooled regressions of the between-variety components on mean were all positive. It is suggested that this information indicates that comparison of varieties for single traits should be carried out on locations favourable for maximum expression of the trait. The difficulties which variety comparisons, for several traits having different optimum management regimes, would cause and the need for a more intensive investigation of the conditions conducive to genotype-environment interactions are stressed.