Random regression (RR) analysis has been recommended to estimate the genetic parameters of longitudinal data. The objective of this study was to evaluate the growth of turkeys using RR models. Data were collected from 957 turkeys and included 15 478 individual body weight recorded during the first week of life and between weeks 2 and 32 by 2-week intervals. To take into account the repeated measurements of weight for each animal, a specific overall growth curve was modelled using a cubic smoothing spline. Animal deviation to this curve was also modelled using an RR function. All data were analysed with the ASReml package. The results showed an increase in heritability estimates over the trajectory and peaked at 0.60 around 20 to 32 weeks of age. Genetic correlations showed that turkeys could be selected at earlier time points, at 12 weeks of age, in order to increase the growth rate. In general, genetic correlation estimates were higher among adjacent ages, decreasing markedly with the increase of distance between ages. Negative genetic correlations were observed between ages.

The optimal balance of amino acids in the diet of the growing pig was estimated by ARC (1981) on the basis of a number of disparate studies augmented by data on the amino acid composition of the whole body on the premise that the amino acids incorporated into accreted body proteins are the major determinant of requirements and that this pattern is not distorted by inequalities in the utilisation of individual amino acids. In an accompanying paper (Wang & Fuller, paper no. 91) an optimal pattern was derived by direct experiment which was shown to be utilised better than that described by ARC (1981). That pattern, however, which related to one particular rate of nitrogen input and the particular rate of protein accretion which that input supported, includes two components, a requirement for maintenance and a requirement for protein accretion. There is clear evidence from studies with rats and chicks that the optimal pattern of amino acids for maintenance and growth are quite different and so the optimal pattern for any particular rate of growth will depend on the relative contributions of the two components. The purpose of this experiment was to estimate both.

The effect of cereal straw supplement on turnip diets has been studied in Romanov × Rasa Aragonesa ewes in early lactation. Measurements were made of level of intake, blood characteristics and performance under pen-fed and grazing conditions. Barley straw supplementation resulted in a proportional increase of 0·1 in turnip intake to give daily intakes of 82 and 94 g organic matter per kg M0·75 for pen-fed and grazing ewes respectively.

Ewes fed on turnips showed a significant decrease in red blood cell numbers, haemoglobin and packed cell volumes though remaining within the range considered as normal for this species. Heinz bodies were present in proportionately up to 0·25 of erythrocytes and no clinical symptoms were observed.

The average weight gain of lambs reared by the grazing ewes was 173 g/day. However, growth rates of lambs and weight losses of ewes on turnip diets were lower than expected from the performance of animals on a control diet based on barley, lucerne and straw.

Data on calves sired by Charolais bulls and their contemporaries in 22 commercial herds in Northern Ireland indicate that the Charolais calves were significantly heavier than their contemporaries at weaning as well as at birth. Although the weight of dam was also significantly greater for the Charolais calves, all the evidence indicated that this was not associated with calf weight and did not, therefore, invalidate the conclusion on calf weights.

The present results suggest that although interaction between breed of sire and sex is not statistically significant for calf weights neverthe-less the superiority of Charolais sires was much greater for males than for females. The interaction was significant for daily gain to weaning. Separate analyses for the two sexes indicated that the Charolais-cross males gained significantly better than their contemporaries whereas no significant difference in gain could be detected in the females.

An experiment was undertaken to examine the possibility that progressive adjustments in tissue insulation on the trunk might occur following repeated wind cooling. Two sheep were exposed at right angles to an air flow of 12 mph for 6 hr daily on each of 7 consecutive days.

When first exposed to the wind the heat loss from the fleece-covered surfaces increased due to a reduction in insulation and apparently increased vaso-dilatation. After the first day there was a progressive increase in surface vaso-constriction before exposure and a gradual decrease in the extent of the vaso-dilatation during exposure. The results indicate the possibility of centrally-induced peripheral adjustments in blood flow occurring on the trunk of the sheep in response to repeated wind cooling.

An initial experiment was conducted to investigate the variability of selected metabolites in the plasma from guanacos. A second experiment directly compared plasma biochemical values for guanacos with those for sheep. During the first experiment, jugular blood samples were collected from five mature castrated guanacos using an embedded experimental design. Weekly blood samples were collected at the same time (09.00 h) on the same day each week for 7 weeks. Daily blood samples were collected at the same time each day (09.00 h) during week 5. On day 2 of week 5, blood samples were collected every 3 h from 09.00 h for a 24-h period. No evidence of a cyclical pattern of plasma parameters was observed on a weekly, daily or 3-h basis. During the second experiment, the metabolic profiles of 11 mature castrated guanacos and 11 mature barren ewes (Merino × Welsh Mountain) were compared. Significant differences in plasma concentrations of all metabolites except urea-nitrogen (guanacos -15·42 mmolll, sheep - 15·60 (s.e.d. 1·506) mmolll) were found with values for guanacos v. sheep as follows: glucose (7·63 v. 3·63 (s.e.d. 0·268) mmolll); acetate (0·26 v. 0·48 (s.e.d. 0·035) mmol/l); β hydroxybutyrate (0·06 v. 0·50 (s.e.d. 0·019) mmol/l); albumin (33·4 v. 29·5 (s.e.d. 0·93) g/l); and total protein (53·8 v. 65·6 (s.e.d. 2·12) g/l); (P < 0·001 for all previous variables); non-esterified fatty acids (0·48 v. 0·29 (s.e.d. 0·048) meq per 1; P < 0·01) and a-amino N (2·44 v. 2·66 (s.e.d. 0·088) mmolll; P < 0·05). This study indicates that the reference plasma metabolite concentrations of sheep are not suitable alternatives for use for nutritional or veterinary purposes with guanacos, but those of llamas or alpacas are. The results also suggest that energy capture and transport in camelids may be markedly different from that in conventional ruminants.

Six sheep were used in a Latin-square experiment to investigate the effect of pre-harvest treatment of pasture with glyphosate (Roundup, a translocated herbicide) on the palatability of hay. Four hays were used: control (C), Roundup (R), quinine (Q, 100 mg/kg) and Roundup with quinine (QR). During each week one of the following choices was given to each animal: (a) C/C; (b) C/R; (c) R/R; (d) Q/C; (e) Q/R; and (f) C/QR. There were no significant effects of treatment on the proportion chosen or on total daily intake, mean meal size or rate of eating. It was concluded that neither pre-harvest treatment with Roundup nor post-harvest treatment with quinine affected the palatability of hay.

Forty crossbred heifers, mated to one sire, that calved in a 20-day period were used to study the effect of varying time and level of post-partum nutrition on productivity. Heifers were individually fed for 90 days post partum beginning at parturition: (1) proportionately 1·3 National Research Council (NRC) 1984 recommendations for 45 days followed by 0·7 NRC for 45 days (130·70); (2) 1·0 NRC for 90 days (100·100); and (3) 0·7 NRC for 45 days followed by 1·3 NRC for 45 days (70·130). Milk production, growth and body condition were estimated periodically during the lactation. The 130·70 heifers maintained their weight during the first 45 days of lactation, while the 100·100 and the 70·130 heifers lost weight (−0·33 and 0·60 kg/day, respectively). During the second 45-day period, the 100·100 and 70·130 heifers gained weight (0·24 and 0·72 kg/day, respectively) while the 130·70 heifers lost weight (−0·39 kg/day). Visual condition scores paralleled weight changes during both phases of the feeding period. Milk production varied according to nutrient intake and treatment differences were greatest at 45 days post partum (8·1, 7·3 and 6·1 kg/day for 130·70, 100·100 and 70·130, respectively). Calf weight gains were unaffected by dam nutrition. Days to first oestrus, days to conception or services per conception were not significantly different (P > 0·05) among treatment groups. Based on this experiment, neither of the alternate feeding systems resulted in decreased performance when compared with feeding at a constant level. Therefore, it appears that latitude exists in the way heifers can be fed early in their first lactation, without adversely affecting production.

Heritabilities of birth, weaning, 6-month and yearling weights adjusted for significant non-genetic factors and obtained from half-sib correlations were 0·10±0·03, 0·22±0·05, 0·37±0·09 and 0·48±0·07 respectively. Genetic correlations of birth weight with later weights were small and negative except with weaning weight. Genetic correlations among other weights were large and positive. The phenotypic correlations among these weights were positive and statistically highly significant.

Farm livestock in the U.K. (i.e. Scotland, Wales, and England) enjoys a higher and less vulnerable health status than any country in the European Community (E.C.) other than Denmark and Ireland (Eire and Ulster). There are three main reasons for this. First, the physical barriers of the sea. Only Foot and Mouth disease (F.M.D.) is known to be able to blow across the Channel and then only under very limited climatic conditions. Second, the expertise of the veterinary arm of A.D.A.S., supported by laboratories such as the A.V.R.I, at Pirbright and the C.V.L. at Weybridge. Their ability to eradicate and/or control infectious disease has been well proven over many years. Third, the national control exercised over imports of live animals and animal products. Until now, of course, M.A.F.F. has been able to exercise an efficient safeguard.

To maintain this privileged position, all three factors would have to be maintained intact. The first, the barrier of the sea, would be difficult to erode. The channel tunnel will barely dent it.

Salernitano (SAL) is an ancient Italian horse breed developed over the course of the ages together with Napoletano and, during the 20th century, by crossing with Thoroughbred horse lines. Excellent in hurdle jumping, this breed is currently facing a concrete risk of extinction due to the lack of appropriate management strategies. This research is the first SAL genetic characterization that aims to set up the basic knowledge for a conservation plan. A representative sample of 61 SALs was analyzed by means of a set of 16 microsatellites markers (short tandem repeats (STRs)). The sequence of hypervariable D-loop mtDNA region was also performed on a subset of 24 mares in order to study the maternal diversity and obtain a complete picture of the internal genetic variation. All the molecular data were analyzed together with those obtained from three Sicilian horse breeds investigated in a previous research (Siciliano, Sanfratellano and Sicilian Oriental Purebred). STRs markers revealed a moderate level of genetic diversity in SAL (alleles/locus 5.1, He 0.67) and confirmed the hunch of genetic erosion. Autosomal variability highlighted a very light deficit of homozygotes (FIS=−0.067). Experimental D-loop sequences were compared by multiple alignments with those retrieved from biological databases and revealed two unreported haplotypes. The phylogenetic network, which was built on mtDNA sequences, included various cosmopolitan and European horses and showed SAL haplotypes distributed among different mtDNA lineages.

In a 2 × 2 factorial experiment, the effect of implants of the growth promoter Zeranol, with and without supplementary food, on the growth rate, blood metabolite and hormone profiles of lambs finished at pasture was examined. For lambs fed no supplement, Zeranol implants increased growth rates from 166 to 185 g/day (s.e. of difference = 11·4) whereas for animals fed supplement the response to Zeranol was much greater, the growth rates being 167 and 234 g/day (s.e. of difference = 12·8). Supplement given to lambs not treated with Zeranol replaced a proportion of the herbage intake while, in lambs given supplement and treated with Zeranol, herbage intake was greatly increased (P < 0·001). Plasma glucose and urea concentrations were not affected by treatment but non-esterified fatty acids (NEFA) were depressed and albumin levels increased by Zeranol implants, while supplementary food caused reductions in plasma NEFA and urea concentrations. It is suggested that Zeranol treatment and supplementary food acted synergistically through changes in insulin and growth hormone concentrations to induce a much larger increase in growth rate in the treated animals given supplementary food than in those given either Zeranol or supplement alone. The response to Zeranol may also have been altered by differences in thyroid hormone status associated with supplementary food.

The test proofs of 29 Holstein-Friesian sires (12 Canadian and 17 US) with milking daughters in both Canada and the USA were compared. The mean test rating of the Canadian and US sires respectively was 125±74 kg and 265±57 kg higher in Canada than in the United States.

These results were supported by others obtained in milking trials in Denmark and West Germany.

The fat percentage of US Holstein progeny was higher in Canada and Europe than in the USA, suggesting that the low fat percentage of the US Holstein in its country of origin cannot be attributed simply to lack of genetic potential.

It is suggested that the US Holstein be considered as a substitute for the Canadian for the improvement of milking performance in European Friesian populations.

Fully slatted concrete floors are labour-efficient, cost-effective and thus common in beef cattle housing. However, the welfare of cattle accommodated on them has been questioned. The objective of this study was to evaluate the effect of floor and diet on hoof health and lying behaviours of housed 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 (SD = 23.7) kg, were allocated to 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 overlaid with rubber, while the diets offered were either a high concentrate diet or a grass-silage-based diet supplemented with concentrates. The mean total duration of the study was 216 days. Floor had no significant effect on claw measurements measured on day 62 or 139. However, bulls accommodated on slats overlaid with rubber had a tendency to have a higher front toe length measured pre-slaughter than those accommodated on concrete slats (P = 0.063). Floor had no significant effect on the net growth of toes or heels during the duration of the study. The number of bruises (P < 0.01) and the bruising score (P < 0.05) were significantly higher on day 62 in bulls accommodated on fully slatted concrete floors than on concrete slats overlaid with rubber, but there was no significant effect of floor on these parameters on day 139 or at the measurement taken pre-slaughter. There was a tendency for bulls accommodated on concrete slats to have a higher probability of having sole bruising at the end of the experiment than those accommodated on slats overlaid with rubber (P = 0.052). Diet had no significant effect on toe length or heel height, number of bruises, or overall bruising score at any time point of the study. There was little evidence in the current study to suggest that bulls lying on fully slatted concrete floors could not express lying postures similar to those on concrete slats overlaid with rubber.

The present study tested a hypothesis that dietary fish oil (eicosapentaenoic acid+docosahexaenoic acid) in a commonly achievable dose ameliorates a systemic inflammation in pigs. Two groups of pigs of 16 animals each were fed a diet with either 2.5% of fish oil (F) or a control diet with 2.5% of palm oil (P). After 70 days of fattening, eight F and eight P pigs were challenged (F+; P+) i.v. by lipopolysaccharide. After 3 h, all pigs were sacrificed and blood, liver and visceral adipose tissue (VAT) samples were taken. No significant effect (P>0.05) of dietary oil on the feed intake and daily weight gain was found out. Less neutrophils (16.8% v. 28.8%; P<0.05) were found in the F+-leukocytes of the peripheral blood; F+ pigs had lower (P<0.05) percentage of the swine leukocyte antigen-D-related CD163+ (SLA-DR+ CD163+) macrophages in the VAT (15.4% v. 21.8%) and lower expression of the SLA-DR-CD163+ surface molecules of the VAT macrophages. No difference (P>0.05) between F+ and P+ pigs in the peroxisome proliferator-activated receptor γ, GPR120, Adipor1 and Adipor2 (adiponectin receptor) gene expression, respectively, was established; plasma adiponectin was the same (21.1 ng/ml) in F+ and P+ pigs. In comparison with the P+ pigs, increased expression of the lipopolysaccharide-binding protein (LBP) gene and intercellular adhesion molecule 1 (ICAM1) gene was found out in the liver of the F+ pigs; expression of the tumor necrosis factor α (TNFα) gene was higher in the liver but lower in the VAT of the F+ pigs (P<0.05). The F+ pigs had higher (P<0.05) plasma concentration of both anti-inflammatory cytokine interleukin-4 (0.46 v. 0.04 ng/ml) and pro-inflammatory TNF-α (13.41 v. 7.72 ng/ml). It was concluded that dietary fish oil at the tested amount had a negligible effect on expression of the evaluated receptor genes and plasma adiponectin, and had an ambiguous effect on expression of cytokine genes and plasma cytokine levels.

Data from 726 male and 765 female pigs (364 litters) from 28 threebreed crosses obtained from mating Poland China boars to gilts and sows from different two-breed-crosses were analysed. The 28 two-breed-crosses were obtained from mating Yorkshire (Y), Landrace (Ld), Lacombe (Lc), Hampshire (H), Duroc (D), Berkshire (B) and Large Black (LB) sows to Ld, Lc, H, D, B, LB and Tamworth (T) boars in an incomplete diallel mating design. The traits studied were age at slaughter (72 kg carcass weight), carcass backfat measurement and an index combining both traits.

The youngest pigs to reach slaughter weight were those from LB x D sows (191·3 days) while the oldest were from T x D sows (211·6 days). The pigs with the least depth of backfat were those involving the Hampshire breed (mean 7·28 cm) while those involving the Large Black had the thickest backfat (mean 7·81 cm). In descending order, the five highest ranking crosses based on the index were those from H x Ld, H x Lc, LB x D, Lc x Ld and H x Y sows.

The performance of Hereford × Friesian calves sired by Hereford bulls selected for either lean growth rate (LGR) or lean food conversion ratio (LFCR), or by unselected Hereford bulls, was evaluated on 327 calves on three farms over 2 years. Animals started test at 130 days of age on average and remained on test for approximately 300 days, whereupon all animals were slaughtered and carcass dissections were undertaken. Individual food intake was measured on tioo of the farms (189 animals), but only intake per pen of animals was measured on the third farm and individual food intake had to be estimated. LGR, LFCR and other traits describing performance were calculated from the growth, food intake and carcass composition data.

If no breed or environment interactions exist it is expected that proportionately 0-5 of the genetic differences between selected and control line bulls would be transmitted to their offspring. For the LGR and LFCR line bulls these values were 0·38 and 0·44, respectively, however the LGR value had a much smaller confidence interval. Genetic correlations derived from regressing breeding values predicted from offspring performance on breeding values predicted from the bulk's own performance in the selection experiment were 0·62 (s.e. 0·28) and 0·96 (s.e. 0·28) for LGR and LFCR, respectively. Heritabilities were: live-weight gain on test, 0·27; daily gain, 0·48; food intake, 0·06; food conversion ratio, 0·46; predicted carcass lean content, 0·10; killing-out proportion, 0·10; LGR, 0·36 and LFCR, 0·48.

The paper reports the results of experiments to study the effects of different levels of dietary protein on the performance and carcass quality of bacon pigs fed on a high-energy diet: (a) to make similar rates of live-weight gain on all treatments, (b) to make similar rates of live-weight gain but with the level of protein on some treatments being reduced at 130 lb., (c) to allow ad libitum feed intake on all treatments, (d) to obtain two distinct

patterns of growth (fast-fast and slow-fast) on each of two levels of dietary protein.

In the comparison of the two contrasting patterns of growth there was no significant interaction between rate of gain during the period 40–125 lb. live-weight and level of dietary protein. Differences in carcass density and linear measurements were significant and the results suggest that irrespective of growth pattern there was a carcass response to level of protein.

Where diets of different protein content were given ad libitum or to obtain a uniform growth pattern on all treatments, growth rates were generally good, with little difference in feed intake between the treatments within each experiment; variations in level of protein therefore had little effect on growth rate. In some of the comparisons, significant carcass differences were found in terms of density, dissection data and linear measurements; in others only the density differences were significant.

The results suggest that with each of the feeding systems a level of about 17% crude protein, associated with 12% fish meal, is more likely than lower levels to give lean bacon carcasses. In the one experiment in which the protein level was reduced at 130 lb. live-weight there was no marked effect on carcass composition.

It is well established that the genetic merit of the Holstein-Friesian dairy cow for milk production has increased over the past 20 years. Previous studies have examined the effect of feeding system on indices of body tissue reserves of medium genetic merit Holstein-Friesian dairy cows. The aim of the current study was to examine the weight and concentration of body components in high genetic merit Holstein-Friesian dairy cows, managed on four different grassland-based feeding regimes, using direct measures of body composition. Results indicate that there was no significant effect of different grassland-based feeding regimes on the weight or composition of body components of high genetic merit cows. Therefore, high levels of cow performance can be sustained from very different grassland-based systems of milk production without having a detrimental effect on body tissue reserves.