Fully slatted concrete floors are prevalent in beef cattle housing. However, concerns have been raised about welfare of cattle accommodated on slats. The objective of this study was to evaluate the effect of diet and floor type on the intake, performance and cleanliness of dairy-origin bulls from a mean age of 8 months to slaughter at 15.5 months old. Forty-eight bulls, which had a mean initial live weight of 212 kg (SD = 23.7), were allocated one of four treatments which consisted of two floors and two diets, arranged in a 2×2 factorial design. The floors evaluated were a fully slatted concrete floor and a fully slatted concrete floor covered with rubber; while the diets offered were either a high concentrate diet or a grass silage-based diet supplemented with concentrates. Over the entire experimental period, floor type had no significant effect on intake. Interestingly, however, when bulls were offered concentrates ad libitum, those accommodated on rubber covered slats consumed more concentrates than those accommodated on concrete slats. No effect of floor type on intake was noted when bulls were offered the grass silage supplemented with concentrate diet. There were no significant interactions between floor and diet on animal performance. Animals accommodated on rubber covered slats had a significantly better performance than those accommodated on concrete slats, as assessed by live weight at slaughter and live weight gain/day (P < 0.01) and estimated carcass gain/day (P < 0.05). The diet offered had no significant effect on animal performance. Bulls accommodated on rubber covered slats were significantly cleaner than those accommodated on concrete slats on day 97 (P < 0.001), but there was no significant effect of floor type when measured at other time points in the experiment. It is concluded from this study that diet has an important role to play in assessing bulls’ responses in performance to the effect of covering concrete slatted floors with rubber. Bulls offered a high concentrate diet had a higher concentrate intake, higher performance but a similar feed conversion ratio (FCR) when accommodated on rubber covered slats compared to those accommodated on fully concrete slatted floors. Animals offered this intensive diet were less efficient (as measured by a higher FCR) than those offered a supplemented grass silage-based diet.

The objective of this study was to assess the effect of feeding steam flaked wheat and maize in diets with high and low levels of dairy products and to examine the effect of sequence of feeding the processed cereals in diets for newly weaned pigs. In experiment 1, 96 pigs were weaned at 27 days of age, blocked on sex and weight and assigned as individually penned pigs to four dietary treatments as follows: (a) high dairy product diet (6 kg of starter diet containing 230 g/kg milk powder followed by a link diet containing 125 g/kg milk powder to 26 days) with uncooked cereal (HDP), (b) high dairy product diet with steam flaked cereal (HDPC), (c) low dairy product diet (6 kg of starter diet containing 125 g/kg milk powder followed by a link diet containing no milk powder to 26 days) with uncooked cereal (LDP) and (d) low dairy product diet with steam flaked cereal (LDPC). In experiment 2, 96 pigs were weaned at 19 to 24 days of age, blocked on sex and weight and assigned as individually penned pigs to four dietary treatments containing: (a) uncooked cereal for 26 days, (b) uncooked cereal for 14 days followed by cooked cereal to 26 days post weaning, (c) cooked cereal for 26 days and (d) cooked cereal for 14 days followed by uncooked cereal to 26 days post weaning. Steaming and flaking of wheat and maize did not significantly affect pig performance during the experimental period or at any subsequent period up to slaughter. Daily gain from day 0 to 26 post weaning was 415 and 453 g/day (s.e.13•5; P < 0•05) for low and high dairy product diets, respectively. Food conversion efficiency (FCE) from day 0 to 14 post weaning on the low and high dairy product diets was 1•86 and 1•33 g/g (s.e. 0•14; P < 0•05), respectively. Pigs given the high dairy product diets during the experimental post-weaning period reached final carcass weight 5 days earlier than pigs given the low dairy product post-weaning diets (P < 0•05). In experiment 2, treatment did not affect food intake (mean = 450 s.e. 13•2 g; P > 0•05), daily gain (mean = 382 s.e. 12•5 g; P > 0•05) or FCE (mean = 1•19 s.e. 0•02 g/g; P > 0•05). In conclusion, feeding steamed flaked wheat and maize in post-weaning diets failed to improve pig performance irrespective of dairy product or sequence of feeding cooked cereals.

Forty-five Large White × Landrace gilts were given food to realize energy intakes recommended by the Agricultural Research Council (1981) to attain maternal weight gains in pregnancy of either 40, 20 or 10 kg using a diet containing 125 g crude protein and 12·5 MJ digestible energy (DE) per kg over three parities. During a 3-week lactation period all animals were given a standard level of feeding. Maternal weight gains in pregnancy were much greater than those anticipated, for all treatments during each parity. The relationship between the actual and the predicted weight gains (kg) was the same for all three parities, actual AW = 22·62 + 0·71 predicted AW (R = 0·69). There was a large range of weight gains within treatments which was related to backfat thickness (P2 measurement (mm)) at conception in the second and third pregnancies, AW = 10·52 + 0·62 P2 measurement (R = 0·63) and to the change in P2 measurement, AW = 38·37 + 1·68 AP2 (R = 0·38) in the first pregnancy. The daily gain per MJ DE intake decreased wth parity and with decreasing energy intake. Numbers of piglets born and weaned were similar for all treatments; birth weights were also similar but there was an unexplained significant difference in piglet weaning weight in parity 2. There were no significant differences among treatments for either the total number or weights of piglets produced over the three parities.

1. Two experiments were conducted, one with pigs fed individually on a restricted scale of feeding, and one with pigs fed ad libitum in groups, to test Probioticum as a feed additive with and without nitrovin and zinc bacitracin.

2. Growth rate, feed conversion, killing-out percentage and carcass quality were measured.

3. No significant difference was shown in any of the characteristics measured between diets containing any of the additives, singly or in combination.

Sheep of three pure breeds, the Scottish Blackface, South Country Cheviot and Welsh Mountain, and the crosses among these breeds, were inbred mostly by younger-parent offspring matings for three generations. Observations on lambs at 12 weeks of age were weight of fleece per unit area of skin, mean and variance of fibre length, both primary and secondary follicle density, and fibre diameter. The observations were analysed for the effects of inbreeding of the lamb and its dam, breed type, parity, and the sex and birth type of the lamb. Variation in the traits was also analysed for their relationship to lamb's live weight.

Secondary follicle density and the density ratio (Ns/Np) decreased with inbreeding of the lamb. Primary follicle density increased whilst secondary fibre diameter and mean fibre length decreased with inbreeding of the dam. The effects of inbreeding on the density ratio and on secondary fibre diameter were correlated with inbreeding effects on the lamb's 12-week live weight. For other traits inbreeding did not have a clear-cut effect. Heterosis observed in F2 lambs was in general greater than that previously recorded for F1. For mean fibre length and mean fibre diameter the comparison of the crossbred deviations from mid-parent of the F2 and inbred lambs suggested epistatic interactions were involved. The effect of inbreeding crossbreds and inbreeding purebreds was different for secondary follicle density and primary fibre diameter, the two traits most clearly exhibiting heterosis in the F2. Lambs from first parity ewes had finer primary fibres and lighter fleece samples than had lambs from later parities.

The Oxylog, a portable breath-by-breath gas analyser, was used on seven animals to determine standing metabolic rate, energy cost of walking on soils of different consistencies and efficiency of work ploughing and carting. The average standing metabolic rate of animals was 5·63 (s.e. 0·12) W/kg M00·75. The consistency of the soil on which animals worked had a marked effect on their energy cost of walking which was 1·59 (s.e. 0·069) on unploughed soil, 2·15 (s.e. 0·084) on ploughed soil and 1·0 (s.e. 0·10) J/m per kg live weight on laterite tracks. The efficiency of ploughing sandy soils (i.e. ratio of work done to energy used for work) was 0·32 and was not significantly different from the efficiency of carting with different loads. The efficiency of doing work was not influenced by the type of work performed, the draught force exerted or the walking speed.

Castrated and entire male buffalo calves of about 2 years of age were made to work by pulling a stone roller weighing 80 kg at a constant speed of about 3 km/h on even ‘Kachha’ ground for 3 h. Blood levels of lactic acid and pyruvic acid and the Icteric index increased, whereas blood levels of bicarbonate and proteins decreased in response to exercise. No change was observed in blood glucose or chloride levels. There was no difference in the concentrations of blood constituents of the two groups.

The records of 1397 cows calving in the spring were collected in the years 1979 to 1984. They were from 638 Angus and 759 Hereford × Friesian cows, and were used to examine the dependencies of post-partum anoestrous interval (ppai), length of oestrous cycle after calving, and conception rate to each oestrus after calving.

Two-year-old cows had longer ppai (P < 0·05) than older cows (76 v. 72 days), and Hereford × Friesian cows had shorter (P < 0·05) ppai than Angus cows (68 v. 72 days). Cows due to begin calving on 8 August (early calving) had longer (P < 0·01) ppai than cows due to begin calving on 19 September (71 v. 55 days).

The linear regression between ppai and calving date (−0·60) did not differ between years, nor between early and late calving. Non-parametric regressions showed that the dependence between ppai and calving date was linear between plus or minus 20 days of the mean ppai in both early- and late-calving herds. Outside these limits variability of ppai increased and there was no relationship with calving date.

The length of the first oestrous cycle after calving was 22 days in 2-year-old cows and 24 days in older cows. Second and third oestrous cycles after calving were 20 days for all breeds and age classes. There was a correlation of −0·41 between the ppai and the length of the first oestrous cycle after anoestrum. There was no significant deviation from normality of ppai or the succeeding post-partum oestrous cycle lengths.

The conception rate to the first oestrus after calving was significantly lower (P < 0·01) than for later oestrous periods. The conception rate to first post-partum oestrus showed dependence on the ppai, logit regressions showing a 0·005 to 0·01 proportional improvement in conception at first oestrus per day increase in ppai.

The significance of these results to the construction of mathematical models of reproduction in the beef cow is discussed.

Forty-eight individually-fed Large White pigs, initially 10 weeks of age, were used to test the effects of growth checks induced by severe restriction of feed intake. The checks were imposed at 50 lb. or 100 lb. live-weight and lasted for 5 weeks, during which live-weight gains averaged only 1·6 lb. and 4·1 lb. per pig, respectively. The daily feed allowances of the unchecked controls and of other pigs while not on check were according to a fixed scale based on live-weight. All pigs were slaughtered as their individual weights reached 200 lb. and a number of measurements were made on the carcasses.

Excluding the period of the check, efficiency of feed conversion and rate of gain were better for pigs checked at 50 lb. than for the controls. The difference in age at a given weight caused by the check was narrowed by about 6 days at the end of the experiment. Indications of a similar compensation in growth of pigs checked at 100 lb. were mostly explained by the rapid growth of these pigs before 100 lb. and by the sudden increase i n their weight at the end of the check period which was probably due to increased gut fill.

A check at 50 lb. or 100 lb. did not affect either the specific gravity of the carcass, which was taken as an indication of the overall proportion of lean to fat, the area of ‘eye’ muscle, the depth of backfat over the shoulder, the thickness of streak or the Danish ‘slight of lean’ measurement, but the check at 50 lb. increased the thickness of fat at position (1) over the ‘eye’ muscle. Both checks increased the minimum thickness of back fat in females but not in castrates and reduced the average rump fat in castrates but not in females. It was concluded that the checks did not affect carcass composition although they probably caused changes in the distribution of the backfat.

Changes in tocopherol concentrations in the milk of Shorthorn cows, and blood of their calves associated with a change from a winter diet of hay to lush spring pasture were examined. During the winter feeding period the tocopherol levels in the colostrum (108 μg/100 ml) and milk (40 μg/100 ml) were low. A significant increase occurred in the milk tocopherol concentrations after the cows were turned out to spring pasture. Immediately before the animals were turned out to pasture the tocopherol levels were lower in calves with high serum levels of glutamic oxalacetic transaminase, indicative of muscular dystrophy. Plasma tocopherol levels in all calves increased throughout the grazing period, reaching a maximum average value of 919 μg tocopherol/100 ml after 63 days. Six Limousin × Shorthorn calves out of a total of 41 died with nutritional muscular dystrophy but no mortalities occurred among 26 purebred Shorthorn calves.

Experiments were designed to exchange rumen contents and vary the volumes of rumen contents between two pairs of rumen fistulated cows from herds selected for high (HS) or low (LS) susceptibility o t bloat. After exchanges between HS and LS cows the animals were tested on bloat-potent lucerne. The volume of rumen contents was lower in LS than in HS cows by 3·05 1. Increasing the volume of rumen contents of LS cows caused them to bloat to a degree never previously attained. The degree of bloat (i.e. score) was related to the volume of rumen fluid (r = 0·71) regardless of its origin (HS or LS) or the susceptibility of the recipient cow. The results implied that LS cows from this selection experiment did not bloat because they had a lower relative volume of rumen digesta than HS cows.

The rate of incisor, pre-molar and molar tooth loss was studied in two groups of Masham ewes, one from 8·75 to 12·25 years of age, and the other from 7·25 to 9·25 years of age. Incisors were lost at the rate of 0·93 per year in group 1 and pre-molars from the lower jaw at the rate of 1·04 per year. The rate of loss of molars from the lower jaw and pre-molars from the upper jaw was much slower, whilst there was virtually no loss of molars from the upper jaw.

Mean litter size declined gradually from age 7 in group 1, but there was no decline up to age 9 years in group 2. Lambing percentage declined gradually from age 6 years, with a marked drop after age 10 years caused by an increase in barrenness and lamb mortality. Selling percentage also began to decline from age 6 years but dropped sharply after age 9 years following an increase in the number of lambs having to be reared by hand. Ewe live weight, lamb birth weight and lamb growth to 4 weeks of age showed no decline up to 12 years of age.

In the present study, the rôle of gammaglutamyltransferase (GGT) during lactation has been investigated in the water buffalo. GGT activity has been evaluated in the mammary tissue at 4 and 6 months after calving and during the non-lactating period. The highest GGT activity levels were found at day 120 (32·57±7·41 U per g) of lactation and were statistically higher than those at 180 (10·76±3·6 U per g) or during the non-lactating period (9·86±7·94 U per g). Histochemistry confirmed these findings and revealed that GGT reactivity was distributed throughout the cytoplasm of alveolar epithelial cells. Such results showed that the GGT production is high during lactation thus supporting the hypothesis that this enzyme plays a rôle in determining milk production in water buffalo by supporting milk protein synthesis.

Four castrated crossbred (Karagouniki♂ × Friesian♀) rams were used in a 4 × 4 Latin-square design to determine the apparent digestibility of four diets based on alfalfa hay and maize grain and containing varying proportions of whole cottonseed (WCS). The proportions of WCS studied were 0, 175, 355 and 530 g/kg diet dry matter (DM) and the respective apparent digestibility coefficients of DM were 0·744, 0·716, 0·689 and 0·625; of organic matter, 0·772, 0·739, 0·718 and 0·643; and of neutral-detergent fibre (NDF), 0·409, 0·481, 0·522 and 0·472. The gross energy (GE) apparent digestibility coefficients were 0·745, 0·722, 0·704 and 0·641, for the same order of treatments. The effect of the incorporation of WCS instead of maize grain in the diet in significantly reducing DM, OM and GE digestibility was evident. The lowest digestible energy value of WCS was observed in the treatment with the highest level of WCS.

Two experiments were carried out using 130 Friesian-type castrated males (steers) to compare pelleted dried grass with rolled barley as supplements to high quality grass silage for fattening steers. There were six treatments in each experiment and, in addition, Experiment 1 had a pre-experimental slaughter group. The animals on each treatment were group-fed grass silage ad libitum for 98 and 112 days in Experiments 1 and 2 respectively. The treatments were (1) no supplement, (2) 1·5 kg dried grass, (3) 3·0 kg dried grass, (4) 4·5 kg dried grass, (5) 1·5 kg barley and (6) 3·0 kg barley per head daily. Each increase in the level of supplement depressed silage DM intake but there was no difference between dried grass and rolled barley. At each level of supplementation, live-weight and carcass-weight gain for animals fed dried grass and barley were similar. Responses in terms of live weight and carcass weight to increasing increments of supplementary feed declined as the level of supplementation was increased.

Testicular activity of wild and laboratory strains of Meriones unguiculatus and its seasonal dependence was studied. Comparative intraspecific measurements were performed in adult males of the laboratory strain (LAB) and in male offspring of wild Mongolian gerbils (WF-1 to WF-3). All animals were reared under identical conditions including a constant light regime. LAB and WILD were examined in January, July and October. Testicular spermatozoa were counted, proportions of different cell types were analysed using DNA flow cytometry, and total germ cell transformation was calculated from DNA histograms. Intratesticular testosterone concentrations were measured with an enzyme immunoassay. The results showed that differences of testicular activity are dependent on the season as well as the strain and the generation. The season affected testicular parameters in LAB resulting in lowered testosterone and sperm production in July and October, respectively. In contrast, all testicular cell parameters were significantly lower for WF-1 in January compared with October. These seasonal differences were neutralized or diminished in WF-2 and WF-3. In the WILD, total testicular activity was lower and varied more in all months studied, but the differences compared with the values in LAB decreased in the successive generations. WF-3 showed the lowest discrepancy of testis weight and spermatogenic output compared with LAB. The data suggest endogenous cues for seasonal regulation of spermatogenesis, but this endogenous rhythm seems to be subsided or lost rapidly. These findings indicate rapid, adaptive changes in the early offspring generations from wild populations during breeding in the laboratory.

This paper reports the procedures put into place in the UK for the genetic evaluation of pedigree beef cattle and estimation of genetic trends using a comprehensive model to allow critical analysis of progress made under previous data recording schemes. Live weights of Simmental, Limousin, Charolais, South Devon and Aberdeen Angus beef cattle, recorded by the Meat and Livestock Commission (MLC) from 1970 to 1992 were analysed, as part of a project to introduce best linear unbiased predictions (BLUP) of breeding value in the British beef industry. Birth weights were available from MLC or the relevant breed society, (4000 to 84000 records, depending on the breed) and 200- and 400-day weights were estimated by within-animal linear regression on all available weights (resulting in 8000 to 48000 records per breed). Animals were retrospectively assigned to contemporary groups within herds, separately for each trait, taking account of observed calving patterns. Records were adjusted to correct for heterogeneity of variance between herds. BLUP evaluations were then performed within breed, fitting a multivariate individual animal model. In addition to additive direct genetic effects, additive maternal genetic and dam permanent environmental effects were included for birth weight and 200-day weight. Unknown parents were assigned to genetic groups, based on estimated date of birth. The model included fixed effects for contemporary group, sex, month of birth, birth type (single or multiple), embryo transfer births, fostered calves, breed of dam, proportion purebred and age of dam. Genetic trends were estimated by regressing estimated breeding values for animals on their year of birth. Trends in birth weight, 200-day weight and 400-day weight between 1970 and 1992 were approximately 0·09, 0·73 and 1·38 kg per annum respectively for the Charolais breed; 0·08, 0·76 and 1·33 kg per annum for the Simmental; 0·06, 0·53 and 0·89 kg per annum for the Limousin; 0·12, 1·02 and 1·86 kg per annum for the Aberdeen Angus; and 0·03, 0·38 and 0·82 kg per annum for the South Devon breed.

The newborn piglet is prone to hypothermia because of the body heat which is lost in evaporating birth fluids from its surface and because the climatic environment provided for the piglet at birth can be sub-optimal. If deep body temperature drops by over 2°C from the norm of 39° C the pig suffers from reduced locomotor vigour and becomes, more lethargic (Stephens, 1971). Such disadvantages can make the piglet less effective in competing for a teat and colostrum and also more prone to be overlain by the dam (English and Morrison, 1983). Because of the possible consequences of hypothermia, therefore, there is a need to quantify piglet body temperature trends from birth in the variable conditions provided for farrowing and to develop improved approaches for reducing the problem.

Studies in newborn piglets were conducted on a large commercial unit in which farrowing took place in pens with solid floored front creeps with underfloor heating, while the remainder of the pen floor was of woven wire. Mean temperatures (4 cm above floor level) in the front creep and the remainder of the pen were 22.6°C and 21.4°C respectively. Rectal temperature (at a depth of 4 cm) was recorded using a hand held digital thermometer in 168 piglets in 17 litters at 10 minute intervals in the first hour of life, at hourly intervals thereafter up to 10 hours and also at hourly intervals from 24 to 36 hours of age.

The low feed intake and stress associated with abrupt weaning in conventional pig farming often result in poor post-weaning performance, which is related to impaired intestinal function. We investigated effects of housing conditions before weaning on performance around weaning of relatively light and heavy piglets. Before weaning, piglets were housed either with five sows and their litters in a multi-suckling (MS) system or in pens with individually housed sows in farrowing crates (FC). After weaning at 4 weeks of age (day 0), 16 groups of four piglets (two light and two heavy litter-mates) were housed under equal conditions in enriched pens. Mannitol (day −5 and day 5) and galactose (day 5) were orally administered as markers for gastrointestinal carbohydrate absorption, and after 20 min a blood sample was taken (sugar absorption test). In addition, BW, feed intake and faecal consistency as an indicator for diarrhoea, were assessed frequently during 2 weeks post-weaning. Pre-weaning housing, weight class and their interaction did not affect post-weaning faecal consistency scores. Weight gain over 2 weeks did not differ between pre-weaning housing treatments, but MS piglets gained more (0.67±0.12 kg) than FC piglets (0.39±0.16 kg) between days 2 and 5 post-weaning, P=0.02), particularly in the ‘heavy’ weight class (interaction, P=0.04), whereas feed intake was similar for both treatments. This indicates a better utilisation of the ingested feed of the MS piglets compared with the FC piglets in the early post-weaning period. Pre-weaning mannitol concentrations were unaffected by pre-weaning housing, weight class and their interaction. On day 5 post-weaning, however, MS piglets had a lower plasma concentration of mannitol (320 v. 592 nmol/ml, SEM=132, P=0.04) and galactose (91 v. 157 nmol/ml, SEM=20, P=0.04) than FC piglets, regardless of weight class. In conclusion, MS and FC piglets differed in aspects of post-weaning gastrointestinal carbohydrate absorption and in weight gain between days 2 and 5 after weaning, but pre-weaning housing did not affect feed intake, weight gain and measures of faecal consistency over the first 2 weeks after weaning.

In the first of two trials, groups of 10 Chios lambs were fed on long or chopped straw for 13 weeks. They ate 0·61 and 0·65 kg per day, and lost a total of 7·6 and 8·5 kg body weight, respectively. Over the next 20 weeks, the supplementation of chopped straw with either 150 g of soya bean meal or a molasses-urea mixture given ad libitum increased straw intake. The decline in body weight was reversed and the lambs gained 0·04 kg/day on both treatments.

In Trial 2, the intakes of straw by non-lactating ewes were 0·78, 0·78 and 0·70 kg/day with supplements of molasses-urea, barley-urea and barley only, respectively. Ewes on the barley and the barley-urea supplements gained 5·3 and 4·6 kg respectively over the 16-week period whereas those given the molasses-urea supplement lost 2·6 kg.