Dexamethasone (16 mg) induced parturition in sheep when injected i n the dam on day 141 of gestation. The mean time of parturition was 49·0 ±2·18 hr after the injection, with 90% of the injected ewes lambed by the 143rd day of gestation compared with the 147th day in the control group. There was no ill effect on the ewe or the lamb born.

The objective of this study was to examine the effect of increased maternal nutrition in early to mid gestation on changes in serum growth factors of the sow and foetuses. Furthermore, the effect of the foetal sera on in vitro proliferation and differentiation of porcine primary myoblasts was examined. Pregnant sows were either given food either in accordance to requirements (2 kg/day; C) until day 50 or 70 of gestation or given food in accordance to requirements until day 25 and then ad libitum (A) until day 50 or 70. Sows were slaughtered at the Institute's veterinary controlled slaughterhouse at day 50 or 70, respectively. Serum from sows and pools of cord-blood serum from each litter were analysed for glucose, lactate, insulin, insulin-like growth factor (IGF; IGF-1 and -2) and IGF binding proteins (IGFBPs). IGF-1 (P < 0·001) was higher in A compared with C sows, and a 28-kDa IGFBP (P < 0·05) and a 24-kDa IGFBP (P < 0·05) was higher in serum from day 70 compared with day 50 sows. There was no significant effect of food intake on growth factor concentrations in foetal serum or on serum-induced proliferation and differentiation of myoblasts. A 28 kDa IGFBP, IGFBP-2 and -3 were all higher (P < 0·06) and serum-induced proliferation (P < 0·001) and differentiation (P < 0·1) lower at day 70 than day 50. Maternal food intake did not influence the DNA and RNA concentrations and the CPK activity in the foetal longissimus dorsi muscle. The glucose concentration in the liver was higher in C than A foetuses at day 70 of gestation, but not at day 50.

In conclusion, no significant effects of maternal nutrition were found on serum growth factor concentrations in the foetuses or on serum-induced proliferation and differentiation of primary myoblasts.

There are many flocks in Britain where first-cross ewes are mated with a Down ram in order to produce offspring of both sexes to be fattened for slaughter between 3 and 12 months of age. The ewes are normally bred out of hill ewes by rams of the special crossing breeds, the Border Leicester being the most popular example. Commonly the crossbred flock is maintained by the annual buying in of young sheep at 6 or 18 months old. These replace animals lost through normal wastage and those sold after a set number of lamb crops. In such a situation the flock owner relies on others to produce his crossbred ewes and can himself do nothing to improve their performance through selective breeding. He can only attempt to cull ewes with a poor performance. Any gains from such culling are, of course, temporary and must be maintained by a regular system of culling within each separate intake of females. The success of a culling scheme depends partly upon the extent to which future production is predictable from past performances. This is normally assessed by the correlation between an individual's successive records: the intra-class correlation or repeatability (t). The work reported here estimates the repeatability of various productive traits within two crossbred ewe flocks and considers the scope for culling within such flocks.

Twenty-nine Holstein-Friesian and 20 Norwegian dairy herd replacements were used to investigate the effect of habituating heifers to the milking parlour environment prior to calving on subsequent lactational performance. The heifers commenced the study at 3 weeks prior to calving when they were allocated on the basis of breed, genetic merit and live weight to either a habituation or no habituation (control) treatment. Heifers were housed together in cubicle accommodation with grass silage offered ad libitum along with 1 kg of concentrates per head per day offered in the feeding passage (control treatment) or in the food managers in the milking parlour (habituation treatment). Animals in the habituation treatment were exposed to the full milking parlour routine once daily (afternoon milking) in a 20-point rotary herringbone parlour. Holstein-Friesian heifers averaged 2.6 kg/day more milk than the Norwegian replacements. Holstein-Friesian heifers also had higher fat and protein yields than Norwegian heifers, however they also lost more body condition during the first 3 months of lactation. Habituated heifers yielded on average 1.3 kg/day more milk (P < 0.001) than the control group of heifers over the first 100 days of lactation (26.7 v. 25.4 (s.e.d. 0.38) kg/day), with the difference being greatest in the first 2 to 3 weeks of lactation. In early lactation, animals on the habituation treatment lost more live weight (0.16 v. 0.02 (s.e.d. 0.061) kg/day) (P < 0.05) and body condition than those on the control treatment. Duration of milking was longer (P < 0.001) (378.4 v. 340.5 (s.e.d. 6.53) s) and milk flow rate slower (P < 0.001) (2.20 v. 2.46 (s.e.d. 0.041) kg/min) respectively for the habituation compared with control group. Somatic cell counts (SCC) were lower (P < 0.001) for habituation group (1.66 v. 1.79 (s.e.d. 0.037) log10 SCC per ml), but there was no significant treatment effect on locomotion scores. Reproductive performance was lower for habituated heifers, with increased intervals to conception (P < 0.05) (102 v. 83 (s.e.d. 9.22) days). Habituating heifers to the milking parlour environment prior to calving increased milk production but appeared to have some detrimental effects on reproductive performance.

Stochastic simulation was used to compare the results of alternative breeding systems in a sheep population divided into 10 flocks of 120 ewes. The breeding systems compared were selection within closed flocks (CF), a closed nucleus system (CNS), an open nucleus system (ONS) and open nucleus systems with the selection of nucleus replacements being restricted to either nucleus born males (ONSRm) or nucleus born females (ONSRf). Selection was for a best linear unbiased prediction of breeding value for lamb live weight which had a heritability of 0·17. The open nucleus breeding systems (ONS, ONSRm, ONSRf) resulted in higher rates of genetic gain, more predictable selection responses and lower rates of inbreeding than either the closed nucleus system (CNS) or selection within closed flocks (CF). Initial genetic differences between flocks resulted in higher rates of genetic gain in the nucleus breeding systems due to the use of between flock genetic variance. In the ONS system up to 25% of nucleus sires and approximately 50% of nucleus dams were born in base flocks. Nevertheless if selection of either nucleus sires or dams was restricted to nucleus born animals there was very little change in genetic gain or rate of inbreeding.

Gestation length and birth weight of 939 calves born at Santa Monica Experimental Station, Valenc, a, State of Rio de Janeiro, were studied. The calves were of six red and white Holstein-Friesian (HF) × Guzera (G) grades: 1/4, 1/2, 5/8, 3/4, 7/8 and ≥ 31/32.

As the grade × sex interaction for birth weight was significant, data for each sex were analysed separately. A model, including the effects of grade, year-season of birth, grade × year season interaction and age of dam as a covariate, resulted in the following least-square means for the six grades in the above order (± s.e.): gestation length for cows carrying male calves, 290·0 (± 0·9), 281·2 (± 0·9), 285·3 (± 0·8), 278·8 (± 0·9), 280·5 (± 0·9) and 279·3 (± 0·9) days; gestation length for female calves, 287·5 (± 0·9), 280·1 (± 1·0), 285·3 (± 0·9), 274·5 (± 1·1), 279·2 (± 0·9) and 276·4 (± 1·0) days; birth weight for males, 34·6 (± 0·7), 28·6 (± 0·8), 34·2 (± 0·7), 32·4 (± 0·7), 35·0 (± 0·7) and 34·7 (± 0·7) kg; birth weight for females, 29·9 (± 0·6), 29·5 (± 0·7), 33·4 (± 0·6), 31·9 (± 0·7), 33·6 (± 0·6) and 32·6 (± 0·6) kg.

Direct (g1) and maternal (gM) breed additive effects (HF - G), and direct (h1) and maternal heterosis (hM) were estimated. The estimates of g7, gM, h1 and hM were respectively, for gestation length for male calves: -21·5 (± 1·9), 10·6 (± 2·1), 1·5 (± 1·8) and -1·6 (± 11) days; for gestation length, for female calves: -21·9 (± 2·1), 14·6 (± 2·5), 5·7 (± 2·1) and -1·5 (± 1·2) days; for birth weight of male calves: -3·5 (± 1·5), 7·1 (± 1·8), -0·6 (± 1·5) and 1·0 (± 0·9) kg; and for birth weight of female calves: 4·7 (± 1·4), 4·1 (± 1·6), 2·8 (± 1·3) and 2·0 (± 0·8) kg. The difference in birth weight between males and females was 4·7 (± 0·9) for G-sired calves and 0·8 (± 0·4) for HF-sired calves.

Leptin has an important rôle in the control of appetite and energy expenditure. Several studies have reported the effects of leptin in ruminants. However, little is known about changes in circulating leptin concentrations in neonates of ruminant species, or the effects of weaning on plasma leptin concentrations. The main objectives of this experiment were: to examine plasma leptin concentrations in lambs, in the period from just after birth through to weaning; to examine the effect of weaning on plasma leptin concentrations, and to compare leptin concentrations measured using a ‘multi-species’ leptin radio-immunoassay (RIA) kit and a specific ovine RIA in lambs during the 6-month period after weaning. In a previous paper, we reported leptin concentrations using a commercial RIA during the post-weaning period. However, we were not able to measure plasma leptin concentrations from just after birth to weaning as they were apparently below the level of sensitivity of the assay. In the present study, five crossbred lambs were removed from their dams within 2 days after birth, and bottle-fed on milk replacer at a level sufficient to meet a 1•2 times maintenance metabolizable energy intake. Lambs were weaned 45 days after birth, and housed individually in pens. The lambs were offered timothy hay, rolled barley and soya-bean meal to meet a 200 g daily gain during the post-weaning period. During the pre-weaning period, blood samples were collected within 5 h of birth and thereafter at 09:00 h; every day from 2 to 6 days of age; at 2-day intervals from 6 to 14 days of age; and at 3-day intervals from 14 to 45 days of age. During the post-weaning period, blood samples were collected before and 3 and 6 h after the morning meal at the ages of 0•5, 1, 2, 3, 4, 5 and 6 months. Plasma leptin concentrations slightly increased (P < 0•05) just after birth and then remained constant until 45 days old (P > 0•05). Additionally, plasma leptin concentration was not significantly changed following weaning. During the post-weaning period, plasma leptin concentrations were compared using two RIA systems. The correlation between plasma leptin concentrations measured by the ‘multi-species’ leptin RIA kit and specific ovine RIA was poor (r = 0•41). These findings are consistent with other reports and suggest that the ‘multi-species’ leptin RIA kit is not suitable for estimating leptin plasma concentrations in ruminants.

Twenty-seven mature boars were housed in individual pens for 9 weeks under one of the following social conditions: isolated from female pigs; near sexually non-receptive female pigs; and near sexually receptive female pigs. The sexual behaviour of the boars during the 9-week treatment period was observed weekly in standard 15- min tests. The sum of the individual courting behaviour activities and the total time spent ejaculating were significantly greater for the boars housed near either sexually receptive or sexually non-receptive females than for those boars isolated from female pigs (P<0·01 and P<0·05, respectively). Although the boars housed near sexually receptive and sexually non-receptive females achieved 43 and 38% more copulations, respectively, than those isolated from females, the difference was significant only for the latter comparison (P<005). There was no consistent difference in testosterone concentration over a 12-h period between boars housed near sexually-receptive females and those isolated from females.

β-Casomorphin is an opioid-like bioactive peptide derived from β-casein of milk that plays a crucial role in modulating animal’s feed intake, growth, nutrient utilization and immunity. However, the effect of β-casomorphin on lipid metabolism in chickens and its mechanism remain unclear. The aim of this study was to investigate the effects of β-casomorphin on fat deposition in broiler chickens and explore its mechanism of action. A total of 120 21-day-old Arbor Acres male broilers (747.94±8.85 g) was chosen and randomly divided into four groups with six replicates of five birds per replicate. Three groups of broilers were injected with 0.1, 0.5 or 1.0 mg/kg BW of β-casomorphin in 1 ml saline for 7 days, whereas the control group received 1 ml saline only. The results showed that subcutaneous administration of β-casomorphin to broiler chickens increased average daily gain, average daily feed intake and fat deposition, and decreased feed : gain ratio (P<0.05). The activity of malate dehydrogenase in the pectoral muscle, liver and abdominal adipose tissue was also increased along with the concentrations of insulin, very-low-density lipoprotein and triglyceride in the plasma (P<0.05). The activity of hormone-sensitive lipase in the liver and abdominal adipose tissue and the concentration of glucagon in the plasma were decreased by injection with β-casomorphin (P<0.05). Affymetrix gene chip analysis revealed that administering 1.0 mg/kg BW β-casomorphin caused differential expression of 168 genes in the liver with a minimum of fourfold difference. Of those, 37 genes are directly involved in lipid metabolism with 18 up-regulated genes such as very low density lipoprotein receptor gene and fatty acid synthase gene, and 19 down-regulated genes such as lipoprotein lipase gene and low density lipoprotein receptor gene. In conclusion, β-casomorphin increased growth performance and fat deposition of broilers. Regulation of fat deposition by β-casomorphin appears to take place through changes in hormone secretion and enzyme activities by controlling the gene expression of lipid metabolism and feed intake, increasing fat synthesis and deposition.

The interest to develop assisted reproductive technologies and cryobanking for farm animal genetic resource conservation has recently increased. However, cryopreservation for ex-situ management of genetic diversity sometimes is not routinely feasible, owing to the lack of facilities (AI centres, laboratories) and expertise near the local breed farming area. In these cases, epididymal sperm obtained from slaughtered or castrated animals, associated with the possibility of managing rather long periods between animal death, sperm recovery and freezing, would increase the opportunities to create semen storages. This investigation addresses the pre-freeze/post-thaw quality of goat epididymal sperm as a function of testicle storage temperature (environment or +5°C) and time elapsed between animal’s death and sperm recovery (0, 24, 48, 72 h) to establish the optimal protocols for the recovery and cryopreservation of epididymal sperm in this species. Testicles of 50 mature bucks collected at the abattoir were divided in two groups: half of the testicles (n=50) were transported to the laboratory at environment temperature (E), whereas the remaining half (n=50) at a refrigeration temperature (R) of +5°C. In the two groups (E) and (R), one testicle from each pair was processed after slaughter forming the time 0 groups (0E and 0R). The contralateral testicle was processed after 24, 48 or 72 h of storage, at the corresponding temperature. Sperm motility and kinetic parameters, viability and morphology were assessed in pre-freeze and post-thaw samples. Until 48 h postmortem, both E and R temperatures are able to maintain good pre-freeze epididymal sperm quality. After 48 h postmortem, R temperature is fundamental to reduce epididymal sperm quality decay in pre-freeze samples. Moreover, testicle refrigeration also has a positive impact on post-thaw samples, allowing a lower decline through time considering total motility, kinetics parameters, sperm viability and sperm abnormalities. Therefore, when sperm cryopreservation is not immediately practicable, goat testicles should be transported and stored at 5°C up to a maximum of 48 h postmortem to ensure an acceptable sperm quality.

A total of 1922 first generation crossbred cows born between 2005 and 2012 produced by inseminating purebred Israeli Holstein cows with Norwegian Red semen, and 7487 purebred Israeli Holstein cows of the same age in the same 50 herds were analyzed for production, calving traits, fertility, calving diseases, body condition score, abortion rate and survival under intensive commercial management conditions. Holstein cows were higher than crossbreds for 305-day milk, fat and protein production. Differences were 764, 1244, 1231 for kg milk; 23.4, 37.4, 35.6 for kg fat, and 16.7, 29.8, 29.8 for kg protein; for parities 1 through 3. Differences for fat concentration were not significant; while crossbred cows were higher for protein concentration by 0.06% to 0.08%. Differences for somatic cells counts were not significant. Milk production persistency was higher for Holstein cows by 5, 8.3 and 8% in parities 1 through 3. Crossbred cows were higher for conception status by 3.1, 3.6 and 4.7% in parities 1 through 3. Rates of metritis for Holsteins were higher than the crossbred cows by 7.8, 4.6 and 3.4% in parities 1 to 3. Differences for incidence of abortion, dystocia, ketosis and milk fever were not significant. Holstein cows were lower than crossbred cows for body condition score for all three parities, with differences of 0.2 to 0.4 units. Contrary to comparisons in other countries, herd-life was higher for Holsteins by 79 days. A total of 6321 Holstein cows born between 2007 and 2011 were higher than 765 progeny of crossbred cows backcrossed to Israeli Holsteins of the same ages for milk, fat and protein production. Differences were 279, 537, 542 kg milk; 10.5, 17.7, 17.0 kg fat and 6.2, 12.9, 13.2 kg protein for parities 1 through 3. Differences for fat concentration were not significant, while backcross cows were higher for protein percentage by 0.02% to 0.04%. The differences for somatic cell score, conception rate, and calving diseases other than metritis, were not significant. Holstein cows were lower than backcross cows by 1.5% to 2.5% for conception status in parities 1 to 3 and lower for body condition score for parities 1 and 2, with differences in the range of 0.06 to 0.09 units. Culling rates were higher, and herd-life lower for the crossbred cows. The gains obtained in secondary traits for crossbred cows did not compensate for the major reduction in production.

Two hundred and thirteen Suffolk × (Cadzow Improver × Scottish Blackface) young female sheep were mated either after the natural occurrence of puberty or at 140, 182 and 224 days of age in Year 1 and 140 and 182 days of age in Year 2 after treatment with progestagen (MAP) and 750 i.u. PMS; 90 to 100% of sheep ovulated after hormone treatment. Few sheep were found with embryos or live lambs in Year 1, possibly because of inadequacies in artificial insemination. In Year 2, after natural mating, the incidences of cleaved ova, live embryos 26 days after mating and live lambs born were 82, 33 and 23% respectively for sheep mated at 140 days; 100, 31 and 23% respectively for sheep mated at 182 days; and 100, 62 and 31% respectively for sheep mated after puberty. The occurrence of a second post-treatment ovulation in sheep without embryos at 26 days increased with age at treatment.

In order to describe the lactation curves of milk yield (MY) and composition in buffaloes, seven non-linear mathematical equations (Wood, Dhanoa, Sikka, Nelder, Brody, Dijkstra and Rook) were used. Data were 116 117 test-day records for MY, fat (FP) and protein (PP) percentages of milk from the first three lactations of buffaloes which were collected from 893 herds in the period from 1992 to 2012 by the Animal Breeding Center of Iran. Each model was fitted to monthly production records of dairy buffaloes using the NLIN and MODEL procedures in SAS and the parameters were estimated. The models were tested for goodness of fit using adjusted coefficient of determination ( $$_{{{\rm adj}}}^{2} $$ ), root means square error (RMSE), Durbin–Watson statistic and Akaike’s information criterion (AIC). The Dijkstra model provided the best fit of MY and PP of milk for the first three parities of buffaloes due to the lower values of RMSE and AIC than other models. For the first-parity buffaloes, Sikka and Brody models provided the best fit of FP, but for the second- and third-parity buffaloes, Sikka model and Brody equation provided the best fit of lactation curve for FP, respectively. The results of this study showed that the Wood and Dhanoa equations were able to estimate the time to the peak MY more accurately than the other equations. In addition, Nelder and Dijkstra equations were able to estimate the peak time at second and third parities more accurately than other equations, respectively. Brody function provided more accurate predictions of peak MY over the first three parities of buffaloes. There was generally a positive relationship between 305-day MY and persistency measures and also between peak yield and 305-day MY, calculated by different models, within each lactation in the current study. Overall, evaluation of the different equations used in the current study indicated the potential of the non-linear models for fitting monthly productive records of buffaloes.

This study investigated high mortality in broilers transported to slaughter in Norway by comparing data from flocks with normal and high mortality during transportation. The data sources consisted of necropsy findings in 535 broilers dead-on-arrival (DOA), production data and slaughterhouse data, along with average journey duration for the 61 associated flocks. The mean Norwegian DOA% for 2015 was 0.10. In this study, normal-mortality flocks were defined as flocks with a mean DOA% up to 0.30 and high mortality as flocks with a mean DOA% above 0.30. DOA% was calculated per flock. The most frequent pathological finding was lung congestion which was observed in 75.5% of the DOA broilers. This postmortem finding was significantly more common in broilers from high-mortality flocks (89.3%) than in DOA broilers from normal-mortality flocks (58%). The following variables had a significantly (P<0.05) higher median in the high-mortality flocks: flock size, 1st week mortality, foot pad lesion score, carcass rejection numbers and journey duration. The results indicate that high broiler mortality during transportation to the abattoir may be linked to several steps in the broiler production chain. The results suggest that preventive measures are to be considered in improvement of health and environmental factors during the production period and throughout the journey duration.

A mathematical model based on the energy requirements of the dairy cow and the lactation model of Wood was constructed to determine the effect on net returns over concentrates of different calving intervals for different weeks of the year under different feeding management conditions. The model was computerized, and this enabled an investigation of the effect on net returns of varying silage metabolizable energy levels and different nutritional management systems. The importance of the modelling approach in examining a range of interacting factors simultaneously is highlighted. To illustrate this approach, results are presented here with 1981 prices for milk, concentrates and calves kept constant over a period of 4 years and also, to validate this approach, using actual prices paid over the period 1976 to 1981.

Seven- to 10-month-old calves are the typical production of Galician Blond (GB), the most important bovine local beef breed in Spain. As meat lipid repercussions on human health depend on their fatty acid (FA) profile, this study aimed at analysing the individual FA at weaning and at the end of the feeding finishing period, especially trans and cis 18:1 isomers in total lipids of the Longissimus thoracis muscle in GB male calves. Distribution of main FA in veal lipids was characterized by gas–liquid chromatography (GLC) analysis on a high polar glass capillary column. Total trans and cis 18:1 isomers were purified, from total FA (TFA) methyl esters, by preparative reversed-phase high-performance liquid chromatography, to allow subsequent specific analysis of their different isomers by GLC. Calves stayed with their mothers at pasture for 2 or 5 months in intensive or semi-extensive systems, followed by an indoor feeding period. The weaned (W) group was finished on concentrate and hay, whereas the non-weaned (NW) group was finished on concentrate and hay and it continued suckling until slaughter. The studied effects did not present interactions. The duration of the indoor finishing period hardly had a significant influence on the parameters analysed. Compared to W calves, NW calves had higher proportions (% TFA) of 18:3n-3 (+38%, P < 0.0001), 20:5n-3 (+22%, P = 0.005), 22:5n-3 (+13%, P = 0.042), cis monounsaturated FA (MUFA; +8%, P = 0.032), total MUFA (+8%, P = 0.013), n-3 polyunsaturated FA (PUFA; +25%, P = 0.0001) and conjugated linoleic acid (CLA; +48%, P < 0.0001) to the detriment of 18:0 (−10%, P = 0.002), 18:2n-6 (−25%, P = 0.004) and n-6 PUFA (−20%, P = 0.011). With regard to cis and trans 18:1 isomers, NW calves had higher proportions (% total cis or trans 18:1) of Δ11trans and Δ16trans (+25% and +22%, respectively, P < 0.01) and Δ13 + 14trans (+13%, P < 0.05) and lower proportions of Δ6 to 8 and Δ10trans (−28% and 58%, respectively, P < 0.001). NW calves’ meat might be more suitable for human health than W calves’ meat due to the increase of anti-atherogenous FA such as n-3 PUFA, CLA and 18:1 Δ11trans.

1. Using 12 castrated Large White pigs, the way in which the size and number of recognizable fat cells (i.e. > 6·0 μm) increases during growth from 26 to 109 kg live weight, and the relationships between fat cellularity and body fat content were determined.

2. Fat biopsy samples were taken at 87, 145 and 188 days of age from the shoulder region. This region grew rapidly in volume but was early maturing since its relative growth during the period of the experiment was low compared with other regions, particularly the mid-back to loin region.

3. The growth of fat that occurred during the experiment was due to increases in both the size and number of recognizable cells. There was no indication that the number of cells had become constant even at 188 days of age.

4. Subcutaneous or total fat expressed as a percentage of total dissectible tissue weight was related quite closely (r = 0·6 to 0·7, residual s.d. about 8% of mean fat percentage) to average fat cell size measured at 145 and 188 days. The number of cells at these times, defined as the number in a cylinder whose depth was known and whose cross-sectional area was 1 mm2 on day 1, was not significantly correlated with whole body fatness.

5. Appetite was strongly linked to the rate of fat deposition and to the weight of fat at 188 days, but not to fat expressed in percentage terms. This was, however, closely related to the corrected food conversion ratio (r = 0·90, residual s.d. 2% of mean total fat percentage).

6. Fat thickness measured by ultrasonics before slaughter was no better as a predictor of percentage fat than average fat cell size.

Four ruminally fistulated Holstein heifers (BW = 264 ± 12 kg) were used in a 4 × 4 Latin square design experiment to determine the effect of increasing levels of sodium bicarbonate (BICARB; 0%, 1.25%, 2.50% and 5%, on concentrate dry matter (DM) basis) on DM intake (DMI), water consumption and ruminal fermentation. Sampling was carried out in the last week of each four 21-day experimental periods. Heifers were offered concentrate (13.4 ± 0.04% crude protein (CP), 13.3 ± 0.44% NDF, 51.7 ± 0.97% starch) and barley straw once daily at 0830 h ad libitum. There was a linear decrease in concentrate DMI and a linear increase in straw DMI with increasing buffer level in the diet, resulting in a tendency towards a linear decrease in total DMI. Intake of concentrate was 6.89, 7.66, 6.72 and 5.72 ± 0.83 kg/day, whereas straw intakes were 0.73, 0.84, 0.94 and 1.06 ± 0.14 kg/day, for the 0%, 1.25%, 2.5% and 5% BICARB, respectively. Water consumption was not affected by treatments when expressed as l/day or percentage of BW, but increased linearly when expressed as l/kg of DMI. The percentage of total daily water drunk in the morning (from 0830 to 1230 h) increased linearly with the level of buffer. Mean ruminal pH and total area under the pH curve were not affected with increasing buffer level. The lowest daily pH (5.65 ± 0.09) was not affected by treatments. A quadratic tendency (P ⩽ 0.10) was observed in the number of hours and the area under the pH curve in which ruminal pH was below 5.8, with high values only at the 0% BICARB. Additionally, increasing bicarbonate level caused a linear increase in the ruminal pH at 2 and 4 h after feeding. Daily average NH3 N (2.4 ± 0.9 mg N/100 ml) and total volatile fatty acids (VFA) (143 ± 12 mM) concentrations were not affected by treatments. Daily average molar proportion of propionate decreased linearly, and acetate proportion and the acetate-to-propionate ratio were increased with increasing buffer level in the diet. Molar percentage of butyrate, isobutyrate and isovalerate, and branched-chain VFA concentration increased linearly as the level of bicarbonate increased in the diet. Results indicate that high levels of BICARB to finishing heifers fed high-concentrate diets may result in a decreased DMI without significant effects on mean ruminal pH, which may affect animal performance. All individual VFA proportions, except valerate, were changed by the addition of bicarbonate.

Real-time ultrasound data of backfat thickness, longissimus muscle depth and longissimus area were carried out on 335 pigs (164 gilts and 171 barrows) using the Pie Medical Scanner 200 equipped with an ASP-18 probe and 3·5 MHz to predict carcass lean content in positive stress Pietrain (TT) and negative stress Pietrain (CC or CT). They were given food ad libitum and slaughtered at an average age of 213 days and an average weight of 101 kg. The day before slaughter, longitudinal and transverse images were taken at the last rib. After slaughter, the lean meat content was estimated by a CGM (capteur gras-maigre) equipped with an 8-mm diameter Sydel probe. The carcass lean proportion was higher in homozygote TT than homozygote CC and heterozygote CT individuals (P < 0·05). Gilts had more lean meat than barrows (P < 0·05). The correlation between the lean meat proportion and ultrasound backfat thickness (UBFT) or ultrasound longissimus muscle depth (ULMD) respectively was moderate. The prediction of lean meat proportion using UBFT, ULMD and ULMA gave an R2 which varied from 0·35 to 0·79. Real-time ultrasound is a tool that could potentially be used to predict the composition of pig carcasses before slaughter particularly if measurements can be taken with a higher degree of accuracy than at present.

The effects on genetic and economic responses of adding faecal egg count (FEC) in the aggregate genotype of dairy sheep in Greece were investigated. The extra responses obtained in the full aggregate genotype were expressed as a percentage change of the responses in terms of genetic gain, profit and selection response of single traits before adding the trait. The initial aggregate genotype included the traits milk fat yield (FY) and number of lambs weaned per ewe per year (NLW). Inclusion of FEC in the aggregate genotype resulted always in increased genetic gain and profit. The extra responses from adding the FEC in the index selection were variable and often very large, depending on the parameters varied i.e. the economic weight of FEC and the genetic correlation of FEC with the other production traits. For a wide range in the size of the genetic correlations between FEC and other traits, gains of FEC and no appreciable losses of responses for FY and NLW were predicted when FEC accounted proportionately for 0·10 to 0·20 of the total monetary genetic deviation. While FEC showed a wide range of change, selection responses of FY and NLW remained remarkably insensitive under various weightings of FEC and different genetic correlations of FEC with the production traits. The genetic and economic efficiency of alternative selection schemes were also evaluated. A two-stage selection procedure involving preliminary selection of rams on dam’s FEC, FY, NLW and on their own FEC and final culling on progeny’s FEC, FY and NLW was predicted to be the most efficient in both genetic and economic terms. Female replacements should be selected on dam’s FEC, FY and NLW (first stage) and their own FEC, FY and NLW (second stage). When repeated measurements of FEC are taken, the recommended number of FEC measurements was found to be 4.