Twenty-four Large White × (Landrace × Large White) gilts were allocated to one of four treatments such that one gilt from each of the litters was on each treatment. Three of the treatments involved 30-min daily contact with a boar, the boar being either (1) 2 years of age, (2) 11 months of age, or (3) 6·5 months of age, at the start of the trial. The fourth group were controls, receiving no boar stimulation.

The experiment began at a gilt age of 165 days and continued until puberty was detected. The gilts were slaughtered 5 days after puberty was reached.

The results indicate no significant difference for age at puberty between gilts exposed to the 2-year- or 11-month-old boars (182·0 v. 181·6 days respectively), although both were significantly younger at puberty than gilts exposed to the 6·5-month-old boars or having no boar contact (P<001) (206·0 v. 203·0 days respectively).

This study investigated the effects of genotype and diet on meat fat composition and palatability obtained from Alentejana (AL) and Barrosã (BA) breeds. Herein, 20 males from each breed allocated at 11 months of age were fed ad libitum a low-forage diet or a high-forage diet and slaughtered at 18 months of age. Trained sensory panel analysis found that the longissimus lumborum (Ll) muscle from BA had higher tenderness, juiciness and overall acceptability scores than the AL breed. The highest scores for those attributes were observed in the BA breed fed the high-forage diet. Regarding the semitendinosus (St) muscle, breed was a source of variation of tenderness scores. In contrast to the Ll muscle, the highest tenderness scores for the St muscle were observed in the AL breed. The intramuscular fat (IMF) content was positively correlated with tenderness, juiciness and overall acceptability in Ll muscle and negatively correlated with flavour in the St muscle. The levels of 14:0 and 16:0, 16:1c9, 18:1c9 and 18:1c11 were positively correlated to juiciness, tenderness and overall acceptability in the Ll muscle. These correlations were not observed in the St muscle, which may be related to its low IMF content. Nonetheless, negative correlations were observed for the St muscle between flavour and 14:0, 16:0 and 18:0 FA contents.

The IMF varied widely in the Ll but not in the St muscle. The latter had higher levels of 16:1c9 and trans fatty acids (∑TFA) in the BA than in the AL breed. Regarding the Ll muscle, the BA had higher amounts of 14:0, 16:0, 16:1c9, 18:0, 18:1c9, 18:1c11, saturated fatty acids (∑SFA), cis monounsaturated fatty acids (∑cis MUFA), ∑TFA and n-3 polyunsaturated fatty acids (∑n-3 PUFA) than the AL breed. The diet exerted an influence on the IMF content and on the levels of 14:0, 16:0, 16:1c9, 18:0, 18:1c9, 18:1c11, ∑SFA, ∑cis MUFA and ∑TFA in both Ll and St muscles. Moreover, the levels of ∑n-3 PUFA in the Ll muscle and 18:2n-6, 20:4n-6, ∑n-6 PUFA and ∑PUFA in the St muscle were influenced by diet. The results obtained in this study, with two Portuguese breeds, confirm that genetic background plays a major role in the determination of meat eating quality.

The movement of sows (Sus scrofa domesticus) out of individual gestation stalls and into group housing can introduce new sources of stress due to the enhanced environmental and social complexity. Some sows may have the behavioral capacity to adapt to these changes better than others. However, little is known about individual differences in behavioral responses, or personality traits, in gestating sows and how they impact the animal’s ability to cope with group housing. The temporal consistency in the assessment of an animal’s behavior is a prerequisite to the establishment of personality traits and was addressed at an interval of approximately five months during two consecutive gestation periods in the present study. Forty-six group-housed sows from a commercially available genetic line were assessed for aggressive and social behaviors at mixing into a group, reaction to human approach, ease of handling, exploration of an open field, and reaction to a novel object. Principal component analysis revealed the presence of three traits accounting for over 60% of the variance in behaviors: aggressive/dominant, avoidant of humans and active/exploratory. Individual component scores were significantly correlated between pregnancies demonstrating temporal stability of trait assessment. Significant relationships were found between aggressive/dominant component scores and individual feed rank at electronic sow feeding stations and skin lesion scores, as well as between avoidant of humans component scores and average number of stillbirths per litter. These findings provide evidence for the temporal stability of distinct behaviors contributing to personality traits within a group of genetically similar sows and demonstrate how these traits may be useful in identifying individuals likely to succeed in group housing.

The exogenous enzymes are less consistent in their effects as their beneficial effects depend upon the types and level non-starch polysaccharides (NSP) present in the diets. Therefore, exogenous enzymes should be selected on the basis of types and amount of the NSP in the pig diets. The objectives of the present experiments were to investigate the effects of dietary level of mannan and β-mannanase supplementation on growth performance, apparent total tract digestibility (ATTD) of energy and nutrients, and blood metabolites of growing pigs. In Exp. 1, 96 barrows were randomly allotted to four treatments on the basis of BW. There were four replicates in each treatment with six pigs per replicate. The dietary treatments were a corn–soybean meal (SBM)-based control diet and three other diets consisted of the control diet supplemented with 400, 800 or 1600 U of β-mannanase/kg diet. The final BW, average daily gain (ADG) and blood glucose increased (linear, P<0.05) with increasing concentrations of dietary β-mannanase. The ATTD of dry matter (DM), gross energy (GE) and β-mannan was higher (linear, P<0.05) with increase in dietary β-mannanase concentrations. In Exp. 2, 288 barrows were allotted to six treatments in a 2×3 factorial arrangement of mannan level (high v. low) and addition of β-mannanase (0, 400 or 800 U/kg diet). There were four replicates in each treatment with 12 pigs/replicate. Pigs were fed corn–SBM-based low-mannan diet (6.1 g/kg) or high-mannan (25.2 g/kg) diet in which corn and SBM were partially replaced with 50 g/kg diet palm kernel meal. All diets were fed in meal form for 42 days. Pigs fed diets supplemented with β-mannanase had greater (P<0.05) final BW, ADG, feed to gain (F : G), the ATTD of DM, GE, and β-mannan and blood glucose concentration compared with pigs fed diets without β-mannanase. In addition, the final BW, ADG, F : G and the ATTD of GE and β-mannan were reduced (P<0.05) in low mannan level. The dietary level of mannan and the β-mannanase supplementation had no effects (P>0.05) on the concentrations of blood total cholesterol, triacylglycerides and blood urea nitrogen. These results indicate that supplementation of β-mannanase to low- or high-mannan diets have potential to improve the performance of growing pigs. In addition, palm kernel meal may partially replace corn and SBM without reducing pig performance if β-mannanase is added to diet.

Bovine blood neutrophil oxidative burst activity, the total leukocyte count and its differentiation, as well as progesterone, glucose and cortisol levels were studied on 10 cows from 1 week prior to calving until 8 weeks after parturition.

From day –7 before parturition a decrease in the metabolic oxidative burst activity of neutrophils was observed, reaching the lowest value 3 days after calving (0·28 (s.e. 0·06) nmol/l H2O2 per min 106 neutrophils) (P <0·01). Thereafter, values increased with a maximum of activity 26 days after parturition (0·57 (s.e. 0·05) nmol/H202 per min per 106 neutrophils). At the end of the experiment the neutrophils H2O2-productionwas comparable to values observed on day–7.

The maximum total leukocyte count was observed on the day of parturition (8, 108 (s.e. 370) leukocytes per /A blood) (P <0·01) returning to normal levels about 3 weeks after calving. Lymphocytes and neutrophils showed a trend analogous to that of the total leukocytes. Eosinophils and monocytes did not change during the entire period. With the rapid increase of circulating neutrophils observed on the calving day, a marked left shift was observed with a maximum number of immature neutrophils (48·6%) observed on day +3 (1477 (s.e. 242) immature neutrophils per fjl blood) (P <0·01), reaching normal values about 4 weeks after parturition.

A significant increase (F < 0·01) of plasma glucose was found on the day of parturition (91·4 (s.e. 6·8) mg per 100 ml plasma), while the levels of cortisol reached their maximum 3 days after calving (22·05 (s.e. 8·46) nglml plasma).

Progesterone levels averaged 4·07 (s.e. 1·21) jigll 7 days before calving, declining precipitously to 0·06 (s.e. 0·45) Hg/l 3 days after calving (F < 0·01), remaining very low for a period of about 3 weeks. Minimum and maximum anoestrus post-partum were 22 and 57 days, respectively.

Despite great hormonal variation observed in the peripartum period, no significant correlation was found between measured hormones and the oxidative burst activity of neutrophils.

Eight Border Leicester castrated male lambs (wethers) were fostered on to 8 Merino ewes (MB) at birth, and 10 Merino wethers were fostered on to Border Leicester ewes (BM). Two additional groups of 10 wethers consisted of Border Leicester lambs (BB) and Merino lambs (MM) reared by their natural mothers. The lambs and ewes grazed together and growth rate, and milk and herbage consumption of the lambs were recorded.

Live-weight gains to weaning at 74 days were 275, 245, 204 and 184 g/day for groups BB, MB, BM and MM respectively. Lambs reared by Border Leicester ewes received more milk and consumed less grass than lambs of similar genotype reared by Merinos, but BM lambs consumed less milk than BB lambs. Merino lambs also consumed less grass than Border Leicester lambs.

It was concluded that Merinos grew more slowly than Border Leicester lambs primarily because of their lower voluntary food intake. The lower milk production of Merino ewes was considered to be of secondary significance since if herbage is available ad libitum, lambs with high voluntary intakes will compensate for the lack of milk by consuming more forage.

This study was conducted to verify whether vitamin (Vit) E or natural clay as feed additives has the potential to modulate the deleterious effects resulting from exposure to cadmium (Cd) in growing Japanese quail. 648 Japanese quail chicks (1 week old) were used to evaluate the effects of dietary Cd (0, 40, 80 and 120 mg/kg diet) and two levels of Vit E (0, 250 mg/kg diet) or two levels of natural clay (0 and 100 mg/kg diet) to study the influences of Cd, Vit E, clay or their different combinations on growth performance, carcass traits, some blood biochemical components and Cd residues in muscles and liver. Live BW and weight gain of quails were linearly decreased with increasing dietary Cd levels. Moreover, feed conversion was significantly worsened with increasing Cd level. Mortality percentage was linearly increased as dietary Cd level increased up to 120 mg/kg diet. Carcass percentage was linearly decreased as dietary Cd level increased. While, giblets percentage were linearly and quadratically differed as dietary Cd level increased. Cd caused significant changes in total plasma protein, albumin, globulin, A/G ratio, creatinine, urea-N and uric acid concentrations as well as ALT, AST and ALP activities. Increasing dietary Cd level was associated with its increase in the muscles and liver. Dietary supplementation with 250 mg of Vit E/kg diet or 100 mg clay/kg improved live BW, BW gain and feed conversion when compared with the un-supplemented diet. Quails fed diet contained 250 mg Vit E/kg and those fed 100 mg clay/kg had the highest percentages of carcass and dressing than those fed the un-supplemented diet. Blood plasma biochemical components studied were better when birds received 250 mg of Vit E/kg diet and those received 100 mg clay/kg. Cd residues in the muscles and liver were significantly less in the birds had 250 mg of Vit E/kg or those received 100 mg clay/kg diet than those un-supplemented with Vit E. Growth performance traits and blood plasma biochemical components studied were significantly affected linearly by the interactions among Cd and each of Vit E and clay levels. In conclusion, the present results indicate that the deleterious effects induced by Cd plays a role in decreasing the performance of Japanese quail and that dietary supplementation with natural clay or Vit E may be useful in partly alleviating the adverse effects of Cd.

Digestibility is a key parameter in the evaluation of feeds; however, the measurements on animals require heavy experimental trials, which are hardly feasible when large numbers of determinations are required – for example, in genetic studies. This experiment aimed at investigating the possibility to predict digestibility from NIRS spectra measured on faeces. A total of 196 samples were available from a digestibility experiment investigating the effects of age and genetic background of Large White pigs fed the same diet, rich in fibre (NDF=21.4% DM). Digestibility of dry matter (dDM), organic matter (dOM), nitrogen content (dN), energy (dE) and apparent digestible energy content (ADE) were calculated, as well as total N content of faeces (N). The faeces samples were submitted to reflectance NIRS analysis after freeze-drying and grinding. Calibration errors and validation errors were, respectively, 0.08 and 0.13% DM for total N in faeces, 0.97% and 1.08% for dDM, 0.79% and 1.04% for dOM, 1.04% and 1.47% for dN, 0.87% and 1.12% for dE and 167 and 213 kJ/kg DM for ADE. These results indicate that NIRS can account for digestibility differences due to animal factors, with an acceptable accuracy. NIRS appears to be a promising tool for large-scale evaluations of digestibility. It could also be used for the study of digestibility of different feeds, after appropriate calibration based on a wide range of feed types.

The ability of the biochemical measurements, haem iron, intramuscular fat (IMF%), moisture content, and total, soluble and insoluble collagen contents, to predict untrained consumer sensory scores both across different muscles and within the same muscle from different carcasses were investigated. Sensory scores from 540 untrained French consumers (tenderness, flavour liking, juiciness and overall liking) were obtained for six muscles; outside (m. biceps femoris), topside (m. semimembranosus), striploin (m. longissimus thoracis), rump (m. gluteus medius), oyster blade (m. infraspinatus) and tenderloin (m. psoas major) from each of 18 French and 18 Australian cattle. The four sensory scores were weighted and combined into a single score termed MQ4, which was also analysed. All sensory scores were highly correlated with each other and with MQ4. This in part reflects the fact that MQ4 is derived from the consumer scores for tenderness, juiciness, flavour and overall liking and also reflects an interrelationship between the sensory scores themselves and in turn validates the use of the MQ4 term to reflect the scope of the consumer eating experience. When evaluated across the six different muscles, all biochemical measurements, except soluble collagen, had a significant effect on all of the sensory scores and MQ4. The average magnitude of impact of IMF%, haem iron, moisture content, total and insoluble collagen contents across the four different sensory scores are 34.9, 5.1, 7.2, 36.3 and 41.3, respectively. When evaluated within the same muscle, only IMF% and moisture content had a significant effect on overall liking (5.9 and 6.2, respectively) and flavour liking (6.1 and 6.4, respectively). These results indicate that in a commercial eating quality prediction model including muscle type, only IMF% or moisture content has the capacity to add any precision. However, all tested biochemical measurements, particularly IMF% and insoluble collagen contents, are strong predictors of eating quality when muscle type is not known. This demonstrates their potential usefulness in extrapolating the sensory data derived from these six muscles to other muscles with no sensory data, but with similar biochemical parameters, and therefore reducing the amount of future sensory testing required.

The peri-parturient period is crucial for controlling worms as the acquired immunity of ewes is disrupted, resulting in an increase in faecal worm egg counts. Two hypotheses were tested in this experiment – that ewes bred for worm resistance would have lower faecal worm egg counts than unselected control ewes, during late pregnancy and lactation, under similar but separate grazing areas; and also that numbers of infective nematode larvae would be lower on pastures grazed by resistant ewes than pastures grazed by unselected control ewes. Faecal samples were collected from resistant and unselected ewes in late pregnancy and early lactation, during the winter rainfall season, and analysed for numbers of Trichostrongylus colubriformis and Teladorsagia circumcincta. Pasture samples were taken 1 week before and 7 weeks after lambing started and analysed for infective larvae. In all sheep, worm egg counts rose 2 weeks prior to lambing and continued into lactation. Worm egg counts were significantly lower in the resistant ewes from 1 week before lambing to 2 weeks after lambing. There were no differences in egg counts between single- and twin-bearing ewes in the resistant line. However, twin-bearing control ewes had significantly higher egg counts than single-bearing control ewes. Following lactation, plots grazed by resistant ewes had substantially less contamination with T. colubriformis larvae, but there were no differences in numbers of T. circumcincta larvae. Our results demonstrate that sheep bred for worm resistance has lower worm burdens during the peri-parturient phase and that lambs born to resistant ewes face a lower larval challenge during their introduction to grazing. In our environment, selection for low worm egg counts has produced sheep highly resistant to T. colubriformis, but has had less impact on resistance towards T. circumcincta.

Video image analysis (VIA), carcass shape and colour data were collected for 1211 lambs of known gender, breed type and carcass weight over a 1-week period using the VIAscan® system developed by the Australian Meat Research Corporation. Classification data (thickness of soft tissue over the 12th rib (GR measurement) and subjective conformation scores on a five-point scale of the leg, loin and shoulder) were assessed by an Agriculture and Agri-Food Canada grader after carcasses had chilled at 5°C for 3 to 6 h. Dissections into saleable meat yield (no. = 58) were performed after carcasses had chilled an additional 24 h. The timing of this study, which was dependent on availability of the VIA equipment, influenced the age and type of lambs available for analysis. The majority of lambs evaluated were wool-breed wethers, age > 10 months, of average GR (15·7 (s.d. 0·2) mm) and muscle conformation (3·0, s.d. 0·1). VIA improved the prediction of saleable meat yield (R2 = 0·71, residual s.d. = 14g/kg) compared with the current classification system (R2 = 0·52, residual s.d. = 18 g/kg). Although prediction ofGR measurement by VIA resulted in a large residual error (residual s.d. = 2·4 mm), the proportion of waste fat (perirenal and subcutaneous) and bone dissected from the carcass was accurately predicted (R2 = 0·62, residual s.d. = 11 g/kg). Proportions of leg (R2 = 0·71, residual s.d. = 7 g/kg) and shoulder (R2 = 0·62, residual s.d. = 9 g/kg) primals were also accurately predicted by VIA, although there were no significant predictors for the proportion of the loin (P > 0·15). VIA improved the prediction of saleable meat yield compared with the current classification system. However collection of additional data including some from extremely lean or well muscled animals would be required before VIA could be recommended to classify lamb carcasses

The mean daily digestible organic matter intake (D) of each of 47 adult sheep during a grazing period of mean length 48 days was estimated by the chromium sesquioxide/faecal nitrogen technique. Mean live-weights (W) and mean daily weight gains (G) were also measured.

The regression of D on W and G, and the underlying or functional relationship between D, W and G were both estimated. From the underlying relationship, the preferred equation, the maintenance requirement of a 100 lb. sheep at pasture is estimated to be 1·02 lb. digestible organic matter daily. This value is 24% higher than the corresponding value for housed sheep obtained previously by us.

This result is compared with other estimates of the energy cost of grazing and it is concluded that further work is needed in order to define those circumstances which elevate the maintenance requirements of grazing animals.

The objectives of this study were to investigate the effects of different dietary sources of unsaturated fatty acids (fish oil (FO) and/or linseed oil (LO)) on laying performance, egg yolk fatty acid composition, ovarian follicular development, antioxidative properties, immune response and tibial bone characteristics in aged laying hens. A total of 100 Hisex Brown hens at 56 weeks of age were housed individually in laying cages in an open-sided building under a 16 h light:8 h dark lighting schedule. Hens were randomly divided into four experimental treatments (n = 25 each). Birds were fed ad libitum diets containing 2.5% vegetable oil (C, control), 2.5% FO, 2.5% LO and a mixture of 1.25% LO +1.25% FO (LO + FO) from 56 to 68 weeks of age. Egg production, egg quality characteristics and yolk lipid profile were analyzed. At 68 weeks of age, ovarian follicles were classified and tibial bone characteristics were determined. Serum thiobarbituric acid reactive substance (TBARS), glutathione peroxidase (GSH-Px) activity and total antioxidant capacity were measured. Incorporation of n-3 polyunsaturated fatty acids (n-3PUFA) into the egg yolks has been successful by using dietary FO and/or LO. There were no significant effects of treatments on hen-day egg production, feed intake, egg weight, egg shape index, albumen height, Haugh units and yolk height. However, dietary FO and/or LO supplementation had a significantly positive effect on eggshell percentage, eggshell thickness and yolk color. At 68 weeks of age, there was no significant difference among dietary treatments for tibial bone measurements. Also, no negative effects were detected in ovarian follicular development and weights of the ovary and oviduct, expressed in both absolute terms and relative to body weight. Dietary 2.5% LO, 2.5% FO and a mixture of 1.25% FO + 1.25% LO enhanced GSH-Px activity, total antioxidant capacity and antibody titers significantly in comparison with control. It could be concluded that inclusion of mixed sources of n-3PUFA in diets at moderate levels (2.5%) increased the n-3PUFA content and decreased the n-6/n-3 ratio content in the yolk, improved the antioxidative status, reduced lipid peroxidation, enhanced the antibody response and did not have any negative influence on ovarian follicular development and tibial bone characteristics in aged laying hens.

Myoglobin and haemoglobin concentrations were determined in the m. longissimus dorsi of 133 Dorset Horn × Corriedale lambs, varying in age from 98 to 310 days, and killed at a live weight of 32 kg. Analysis of the data showed that age, over the period studied, was not a critical factor in determining the myoglobin concentration within the muscle. The average pigment level in the muscle of ewes was some 20% greater than in ‘cryptorchids’ and approximately 10% greater than in wethers. Haemoglobin was found to represent about 40% of the total haem pigment.

This study was designed to explore the effect of protein source on muscle susceptibility to lipid peroxidation in two representative species of fish farmed for human consumption: the freshwater rainbow trout and the seawater European sea bass. Four isoproteic diets (digestible protein in the range 366 to 392 for rainbow trout and 391 to 415 g/kg for European sea bass) were formulated to contain one of the following as the main protein source: fish meal, warm water alcohol-extracted or toasted soya protein concentrates or maize gluten meal. Highest daily growth indices were always achieved using the diets based on fish meal as the main source of protein (P < 0·05). Fish of both species given diets containing maize gluten and the toasted soya protein concentrate showed slowest growth. The depressant growth effect of the vegetable protein concentrates was greater in sea bass than in rainbow trout. Dietary treatment was not correlated with any significant effect on whole-body composition or intramuscular fat content except for ash concentration in European sea bass. Under conditions of forced peroxidation in vitro for 240 min, muscle specimens of trout and sea bass given diets containing fish protein as the main source of protein showed the highest peroxidation levels (P < 0·05); while the lowest peroxidation values were found in fish given maize gluten-containing diets (P < 0·05). In the present case, the partial substitution of fish meal with vegetable proteins in diets led to a lower susceptibility of fish flesh to peroxidation. This finding may have applications in the production of fish of improved quality and longer shelf life.

Grasslands being used in sheep farming systems are managed under a variety of agricultural production, recreational and conservational objectives. Although sheep grazing is rarely considered the best method for delivering conservation objectives in seminatural temperate grasslands, the literature does not provide unequivocal evidence on the impact of sheep grazing on pasture biodiversity. Our aim was therefore to review evidence of the impacts of stocking rate, grazing period and soil fertility on plant communities and arthropod populations in both mesotrophic grasslands typical of agriculturally improved areas and in native plant communities. We therefore conducted a literature search of articles published up to the end of the year 2010 using ‘sheep’ and ‘grazing’ as keywords, together with variables describing grassland management, plant community structure or arthropod taxa. The filtering process led to the selection of 48 articles, with 42 included in the stocking rate dataset, 9 in the grazing period dataset and 10 in the soil fertility dataset. The meta-analysis did not reveal any significant trends for plant species richness or plant community evenness along a wide stocking rate gradient. However, we found frequent shifts in functional groups or plant species abundance that could be explained by the functional properties of the plants in the community. The meta-analysis confirmed that increasing soil fertility decreased plant species richness. Despite the very limited dataset, plant species richness was significantly greater in autumn-grazed pastures than in ungrazed areas, which suggests that choosing an appropriate grazing period would be a promising option for preserving biodiversity in sheep farming systems. Qualitative review indicated that low grazing intensity had positive effects on Orthoptera, Hemiptera (especially phytophagous Auchenorrhyncha) and, despite a diverse range of feeding strategies, for the species richness of Coleoptera. Lepidoptera, which were favoured by more abundant flowering plants, also benefited from low grazing intensities. Spider abundance and species richness were higher in ungrazed than in grazed pastures. In contrast, there are insufficient published studies to draw any firm conclusions on the benefits of late grazing or stopping fertilization on insect diversity, and no grounds for including any of this information in decision support tools at this stage.

Embryo transfer following multiple ovulation could allow faster rates of genetic change in sheep, by increasing the effective female reproductive rate. The gains would come from lower generation intervals or increased selection among females, or both. They require good embryo transfer rates at 6 to 8 months of age. These are not adequate at present and need to be improved by research and development, justified by the extra genetic gains shown here to be possible. If high rates of embryo transfer (10 progeny per donor) could be achieved, then, with appropriate selection schemes, the rates of genetic change could be doubled compared with efficient schemes using normal reproduction. This applies to most traits, to those measured before reproductive age (growth traits and carcass traits estimated in the live animal), to female reproductive traits and to wool traits measured at 14 to 16 months of age. With moderate rates of embryo transfer (5 progeny per donor), gains of 50 to 70% in genetic response could be obtained. To limit the rate of inbreeding to moderate levels in a closed selection flock, some 100 to 200 females (1000 progeny) would be required. Application of the methods may be difficult with current breeding structures, and the development of special nucleus selection stocks i s proposed.

In an examination of the productivity of goats and sheep on a Masai group ranch in Kenya, estimated least-squares means for pre-weaning mortality were 28·6% for goats and 32·1% for sheep. Three productivity indices based on total live weight of young produced per female per year, per kg female per year and per kg metabolic weight per year gave values of 11·1 kg, 410 g and 0·99 kg for goats and 14·1 kg, 473 g and 1·18 kg for sheep. The effects of environmental variables on these indices, the comparative advantage accruing to the variables, mortality, reproductive success and weight gain were used to construct a proposed set of interventions for the improvement of small ruminant production in south-central Kenya.

This study investigates the effects of two feeding systems and two dairy cow breeds on milk yield and composition, physical and sensorial properties of Camembert and Pont-l’Evêque cheeses. The experiment consisted of a 2 × 2 factorial arrangement of treatments. A low energy grass diet with only 15% of concentrate (LowGS) was compared with a high-energy maize silage diet with 30% concentrate (HighMS). Thirty-four Holstein (Ho) and 34 Normande (No) cows in early lactation were assigned to one of two feeding systems for a 6-week period. Cows on the LowGS feeding system had lower milk yield, fat and protein content. In both feeding systems, No cows had lower milk yields but higher milk protein contents than Ho cows. The LowGS feeding system altered milk fatty acid (FA) composition by reducing saturated FA. Breed had only a small impact on milk FA. Concerning milk coagulating properties, only the firmness was reduced by the LowGS feeding and the Ho breed. The effects of breed and feeding system on the protein content of cheeses were more marked in Camembert cheese than in Pont-l’Evêque cheese. However, the Camembert cheese from Ho-LowGS was, in fact, characterized especially by lower protein content. LowGS feeding system and No breed produced more yellow cheeses. Feeding systems had limited effects on the firmness of Camembert and Pont-l’Evêque cheeses measured by penetrometry. In sensory analysis, Ho breed and LowGS feeding produced a Camembert cheese with a more melting texture in the mouth due to the increase of spreadability index and of proteolysis. The type of cheese also had an influence: the effects were more important on Camembert cheese than on Pont-l’Evêque cheese. Only the Ho-LowGS treatment produced a very specific Camembert cheese different from the others. The feeding systems and breed of dairy cow have no determinant effect on PDO (protected designation of origin) Camembert and Pont-l’Evêque cheeses, especially regarding taste. In this kind of trial, despite the effects of feeding systems and breed on milk composition, the role of cheese ripening and microbiology appears to be of considerable importance.

A promising tool to improve daily gain in pigs is the missense mutation (Asp298Asn) in the melanocortin-4 receptor (MC4R) gene, especially in the Belgian pig industry where the slow-growing Piétrain breed is very frequently used as the sire breed. The MC4R is expressed in the appetite-regulating region of the brain where it regulates feed intake and energy balance. The mutation has been associated with differences in fatness, daily gain and feed intake. However, less information on the correlated effects on meat quality is available. In order to evaluate the influence of the MC4R mutation on carcass and meat quality parameters, a total of 1155 pigs of a four-way cross were slaughtered at an average live weight of 109 kg, and data about daily live-weight gain, carcass and meat quality were collected. Allelic frequencies were 0.69 for the G-allele (298Asp variant or well-conserved variant) and 0.31 for the A-allele (298Asn variant or the mutated variant). Barrows and gilts were almost equally distributed in this population with, respectively, 49.9% and 50.1%. Moreover, independent of this mutation, the relationship between average daily gain (ADG) and carcass on the one hand and meat quality traits on the other hand was evaluated in this population. A significant positive influence of the MC4R mutation on ADG (P < 0.001) was found, accompanied by a higher fat thickness (P < 0.05) and a lower carcass lean meat content (P < 0.01), whereas muscle thickness and carcass conformation traits were not affected. The effects on meat quality traits were not significant, except for a lower shear force (P = 0.054) and a higher intramuscular fat content (P = 0.052) in AA animals. In the longissimus, pH and pork quality meter (PQM) values were not influenced, and effects on drip loss and colour were not apparent. Residual correlation coefficients between ADG and carcass lean meat content on the one hand and meat quality traits on the other hand were generally very low (|r|>0.1). Higher ADG, higher carcass fat thickness and lower carcass lean meat content were correlated with slightly lower shear force values (|r|∼0.1, P < 0.05). In conclusion, in the studied population, the Asp298Asn mutation in the MC4R gene was associated with improved daily gain, higher carcass fatness and almost no effect on meat quality traits.