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The aim of this Research Reflection is to describe the basic rumen function of goats and its modification in response to environmental factors, as well as to discuss similarities and differences when compared to other ruminants. In so doing we shall reveal the adaptive capacity of goats to harsh environments. The basic rumen function in goats is similar to other species of ruminants, as stressed by the opportunity to apply the updates of feeding systems for ruminants to goats. The rumen epithelium acts as a protective barrier between the rumen and the host, but it can be damaged by toxic compounds or acidosis. The rumen also plays an important role in water balance, both for dehydration and rehydration. Recent studies show that the microbiota exhibits a high fractional stability due to functional redundancy and resilience, but this needs more investigation. The microbial community structure differs between goats and cows, which explains the difference in sensitivity to milk fat depression following intake of high lipid diets. Goats also differ from other ruminants by their enhanced ability to feed-sort, but as with cows they can suffer from acidosis. Nevertheless, goats can be considered to be very resistant to environmental factors such as water stress, salt stress or heat stress, and this is especially so in some endogenous breeds. They also are able to detoxify tannins, polyphenols and other secondary metabolites. Some new trials involving feeding behaviour, microbiota and omics or approaches by meta-analyses or modelling will improve our knowledge of rumen function in goats.

Partie 2 - Déterminants alimentaires et non alimentaires en élevage de la qualité des produits (Chapitre 8); National audience

The objective of the study was to evaluate ruminal biohydrogenation (BH) and apparent transfer of long-chain (FA) from duodenum into milk in dairy goats fed Ca salts of palm oil (CaS, 45 g/d) or lipid-encapsulated conjugated linoleic acids (LE-CLA, 45 g/d providing 4.5 g trans-10, cis-12 C18:2/d and 4.5 g cis-9, trans-11 C18:2/d). Twelve lactating multiparous dairy Saanen or Alpine goats (65±3 days in milk) were randomly allocated to two experimental treatments (CaS vs LE-CLA) for a 3 wks experiment. The goats were fitted with a ruminal cannula and a T-type duodenal cannula for the measurement of duodenal flow by supplying 2.4 g of Cr 2 O 3 /d through the rumen cannula during 3 wks: the first one was for reaching steady-state concentration of this marker in the digestive tract, the second wk was for measuring the daily flow of faecal chrome and nutrient faecal digestibility, and the third wk was for the duodenal sampling. LE-CLA did not affect intake, duodenal flow and apparent ruminal digestibility of DM, OM, NDF and starch. Compared to CaS, LE-CLA tended to decrease total digestibility of DM and NDF whereas total digestibility of starch was not affect by dietary treatments. The duodenal flow of FA was higher than FA intake in goats fed CaS or LE-CLA. LE-CLA increased the duodenal flows of C18:2 trans-10, cis-12, and C18:2 cis-9, trans-11, leading to a calculated 16% protection from BH for both FA. The LE-CLA treatment tended to decrease the duodenal flows of C18:2 cis-9, trans-12 and C18:2 trans-9, cis-12. The ruminal biohydrogenation of C18:1 cis-9, C18:2 cis-9, cis-12, and C18:3 cis-9, cis-12, cis-15 was not affected by the LE-CLA treatment. Average apparent transfer between the duodenum and milk fat was 22%, 44%, 36% and 22% for C18:2 trans-10, cis-12, C18:2 cis-9, trans-11+ C18:1 trans-11, C18:2 cis-9, cis-12 and C18:3 cis-9, cis-12, cis-15, respectively. Apparent transfer efficiency of long-chain FA was not affected by LE-CLA treatment.

Thirty male lambs were assigned to one of 3 concentrate diets supplemented with 45 (El)), 286 (El)) or 551 (E2) mg/kg DM of DL-alpha-tocopheryl acetate to test the effect of vitamin E supplementation on muscle, caudal and perirenal fatty acid (FA) compositions. Specific attention was paid to C18:1 10t, usually observed in high proportions with high-starch or high-unsaturated FA diets. Vitamin E supplementation increased the a-tocopherol plasma concentrations of lambs. It did not modify lamb growth and slaughter parameters. Vitamin E supplementation did not modify FA composition in most tissues but it increased the C18:2 n-6/C18:3 n-3 ratio in muscle and adipose tissues of the El group compared to E0 and E2 groups. Vitamin E supplementation enhanced the C18:1 10t proportion in muscle and adipose tissues and it decreased the C18:2 9c,11t proportion in adipose tissues, especially in the E2 group. These changes may not be favourable for the nutritional value of lamb meat. (C) 2013 Elsevier Ltd. All rights reserved.

The objective of this trial was to study the interaction between the supplementation of lipid-encapsulated conjugated linoleic acid (CLA; 4.5 g of cis-9,trans-11 C18:2 and 4.5 g of trans-10,cis-12 C18:2) and feeding level to test if milk performance or milk fatty acid (FA) profile are affected by the interaction between CLA and feeding level. Twenty-four dairy goats were used in an 8-wk trial with a 3-wk adaptation to the experimental ration that contained corn silage, beet pulp, barley, and a commercial concentrate. During the third week, goats were assigned into blocks of 2 goats according to their dry matter intake (DMI), raw milk yield, and fat yield. Each block was randomly allocated to control (45 g of Ca salt of palm oil/d) or CLA treatment. Within each block, one goat was fed to cover 100% (FL100) of the calculated energy requirements and the other was fed 85% of the DMI of the first goat (FL85). Individual milk production and composition were recorded weekly, and milk FA composition was analyzed in wk 3, 5, and 7. Conjugated linoleic acid supplementation reduced milk fat content and fat yield by 17 and 19%, respectively, independent of the feeding level. It reduced both the secretion of milk FA synthesized de novo, and those taken up from the blood. No interaction between CLA and feeding level was observed on milk secretion of any group of FA. The CLA supplementation had no effect on DMI, milk yield, protein, and lactose yields but it improved calculated net energy for lactation balance. Goats fed the FL100 × CLA diet tended to have the highest DMI and protein yield. The interaction between CLA and feeding level was not significant for any other variables. Compared with the goats fed FL100, those fed FL85 had lower DMI, lower net energy for lactation balance, and lower digestible protein in the intestine balance. The body weight; milk yield; milk fat, protein, and lactose yields; and fat, protein, lactose, and urea contents in milk were not affected by feeding level. In conclusion, reduction in energy spared via fat yield reduction after CLA supplementation was not partitioned toward milk lactose or protein in goats at a low feeding level, possibly because of a simultaneous shortage of energy and amino acids. In goats on the high feeding level, energy spared tended to be partitioned toward milk protein yield, and at the same time to the prevention of excessive lipid mobilization.

In equids, placentation is diffuse and nutrient supply to the fetus is determined by uterine size. This correlates with maternal size and affects intra-uterine development and subsequent post-natal growth, as well as insulin sensitivity in the newborn. Long-term effects remain to be described. In this study, fetal growth was enhanced or restricted through ET using pony (P), saddlebred (S) and draft (D) horses. Control P-P (n = 21) and S-S (n = 28) pregnancies were obtained by AI. Enhanced and restricted pregnancies were obtained by transferring P or S embryos into D mares (P-D, n = 6 and S-D, n = 8) or S embryos into P mares (S-P, n = 6), respectively. Control and experimental foals were raised by their dams and recipient mothers, respectively. Weight gain, growth hormones and glucose homeostasis were investigated in the foals from birth to weaning. Fetal growth was enhanced in P-D and these foals remained consistently heavier, with reduced T3 concentrations until weaning compared to P-P. P-D had lower fasting glucose from days 30 to 200 and higher insulin secretion than P-P after IVGTT on day 3. Euglycemic clamps in the immediate post-weaning period revealed no difference in insulin sensitivity between P-D and P-P. Fetal growth was restricted in S-P and these foals remained consistently lighter until weaning compared to S-D, with elevated T3 concentrations in the newborn compared to S-S. S-P exhibited higher fasting glycemia than S-S and S-D from days 30 to 200. They had higher maximum increment in plasma glucose than S-D after IVGTT on day 3 and clamps on day 200 demonstrated higher insulin sensitivity compared to S-D. Neither the restricted nor the enhanced fetal environment affected IGF-1 concentrations. Thus, enhanced and restricted fetal and post-natal environments had combined effects that persisted until weaning. They induced different adaptive responses in post-natal glucose metabolism: an early insulin-resistance was induced in enhanced P-D, while S-P developed increased insulin sensitivity.

The effects, on the maternal mammary gland, of diets containing similar lipid percentages but differing in composition of polyunsaturated fatty acids (PUFA) have been assessed in rats during pregnancy and lactation. For this purpose, tuna fish oil (an n-3-PUFA-enriched oil) and corn oil (an n-6-PUFA-enriched oil) were included in diets at ratios such that the caloric inputs were the same as that of the control diet. As expected, the maternal diet affected the tissue composition of dams. Unexpectedly, only the tuna fish oil diet had an effect on pup growth, being associated with the pups being underweight between the ages of 11 and 21 days. The maternal mammary gland of rats fed the tuna fish oil diet displayed two main modifications: the size of cytoplasmic lipid droplets was increased when compared with those in control rats and the mammary epithelium showed an unusual formation of multilayers of cells. These results show that the tuna fish oil diet, during pregnancy and lactation, exerts specific effects on mammary cells and on the formation of lipid droplets. They suggest that this maternal diet affects the functioning of the mammary tissue.

Eighty eight lambs were used in a 2 x 2 factorial arrangement 1) to investigate the effect of maternal dietary linseed supplementation and /or lamb linseed supplemented concentrate on growth performance, carcass fat quality and fatty acid (FA) composition of muscle and dorsal adipose tissue of indoor lambs 2) to study the relationships between subcutaneous fat quality and FA composition. Feeding linseed to ewes increased C18:3 n-3 (ALA) proportion in milk and therefore the ALA supply to suckling lambs. However, ALA and n-3 polyunsaturated FA (n-3 PUFA) proportions in lamb tissues were not affected. Feeding linseed to lambs during the post-weaning period significantly increased the proportions of ALA and n-3 PUFA in tissues. Softer and more coloured fat was associated with a decrease in even medium-chain saturated FA and increases in odd and methyl FA proportions but not with ALA proportion in subcutaneous adipose tissue.

Maternal hypercholesterolemia has been shown to lead to fetal intra-uterine growth retardation (IUGR) in rabbits. The effects of a long term maternal hyperlipidemic and hypercholesterolemic diet on embryo, fetal and post-natal development, have not been addressed so far. Rabbit does were fed either a hypercholesterolemic (0.2%) hyperlipidic (8%) (HH) or a control (C) diet from 10 weeks of age. Sixteen does (N = 8 HH and N = 8 C) were euthanized at 18 weeks to assess the effect of the diet on dams before mating. Embryos from 18 females (N = 9 HH and N = 9 C) were collected from the oviducts at the 16-20 cell stage (embryonic genome activation stage) for gene expression analysis (micro array and quantitative RT-PCR). Thirty females (N = 16 HH and N = 14 C) were mated naturally and fetal growth was monitored by ultrasound. Six of them (N = 4 HH and N = 2 C) were euthanized at D28 of gestation to collect fetuses and placentas. Finally, the remaining 24 does delivered at term and litters were cross fostered and equilibrated in number to create 4 groups according to the biological dam and the foster dam (C-C, C-HH, HH-C, HH-HH). Growth was monitored until weaning. A subset of 26 offspring from the 4 groups was fed the control diet until 25 weeks of age and then fed the HH diet for three weeks. All does had similar growth rates and bodyweight. Transcriptomic analyses evidenced an overexpression of Adipophilin in HH embryos at the stage of embryonic genome activation. This was confirmed by quantitative RT-PCR. During pregnancy, IUGR was observed from D9 by ultrasound and subsequently, fetal weight at 28 days, birthweight and fat deposition in newborn offspring were significantly decreased in HH (P < 0.05). After weaning, there was no significant difference for weight between HH-HH and HH-C offspring and both groups became significantly heavier (P < 0.0001) than C-C and C-HH offspring. During the 3 weeks when offspring were fed the HH diet, the differences in feed intake were no longer significant between groups but the differences in body weight remained. At post-mortem, offspring from HH does had significantly more abdominal and inter-scapular fat than offspring from C does (P < 0.05). These data illustrate the importance of maternal nutrition before and during gestation in the establishment and control of the growth trajectory of the conceptus and in the onset of disease in adult life.

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Sixty male lambs were used in two trials to study the efficiency of transfer and elongation of linolenic acid (ALA) in muscle and caudal adipose tissue and to assess factors affecting this process and related changes in fatty acid (FA) profile. In experiment 1, lambs were fed a control diet or extruded linseed (L) diet either with wheat (W, rapid starch) or corn (C, slow starch). In experiment 2, lambs were fed L with ‘‘normal” rapeseed, or high-oleic rapeseed, or soybean. In experiment 1, L increased ALA proportion and total n-3 PUFA in muscle and adipose tissue. In adipose tissue but not in muscle, LC lambs had higher proportion of ALA than LW lambs. In experiment 2, increasing linoleic acid (LA) intake increased LA proportion in muscle and adipose tissue but did not modify ALA proportion. Moreover, in muscle, it did not change the desaturation and elongation processes of ALA to long-chain n-3 PUFA.

A multidisciplinary research programme was developed to get a scientific expertise for the quality assessment of products obtained from cloned livestock. Thirty-seven bovine Holstein female clones of five different genotypes and their products were analysed in comparison with 38 control animals obtained by conventional artificial insemination and raised under the same conditions at the same experimental farm. Animal evaluation included over 150 criteria and more than 10 000 measurements to check the physiological status and health over a 3-year period. All the parameters studied were in the normal range for age and breed, but some significant differences were detected between clone and control groups in terms of delayed onset of puberty in clones, higher neutrophil counts in haematology or lower biochemical plasma concentrations of gamma glutamyl transferase. Milk and meat analyses were conformable to expected values. We, however, found some differences in fatty acid (FA) composition of milk and muscle suggesting a possible deviation in lipid metabolism as assessed by higher delta-9 desaturase activity indexes in both milk and muscles from clones compared with controls. Repeated muscle biopsies in the semitendinosus muscle of the same animals demonstrated a higher oxidative activity in muscle of young clones (8 months of age) compared with controls, suggesting a delayed muscle maturation in clones. Nutritional evaluation of milk and meat using the rat feeding trials did not show any difference between clone and control products for food intake, growth rate, body composition of the rats, nor for possible allergenicity. Possible reactivation of bovine endogenous retroviruses (BERVs) was analysed and compared between normal and cloned cattle. As expected, these BERV sequences are not transcribed and no RNA was detected in the blood of clones, donor animals or controls; therefore, it may be assumed that the sanitary risk associated with BERV sequences is not higher in cattle derived from somatic nuclear transfer than in cattle born from conventional reproduction. Our results confirm that the quality and safety of products (milk and meat) from adult and clinically healthy cloned cattle is globally similar to normal animals. However, from a strictly biological point of view, the slightly delayed maturation we observed in the muscle of clones together with some marginal differences identified in FA composition of both muscle and milk, point to the need for more refined analysis to totally exclude any risks from the consumption of those products.

The effects of linseed content in concentrates on the fatty acid (FA) composition of adipose tissues and muscles of lambs were studied in a 2 × 4 design: males (M) vs. females (F) and linseed content (0%, L0, 3%, L3, 6%, L6, 9%, L9). FA proportions were determined both on a DB-wax and on a CP-Sil column in perirenal (PR), dorsal subcutaneous (SC) adipose tissue and in longissusmus dorsi muscle (IM). No effects of linseed contents in the diet on growth performances either in male or female lambs were observed. Linseed supplementation tended to decrease the fatness score. The proportion of linolenic acid increased linearly with the linseed content in the diet, from: 0.6, 0.5, and 0.5% for L0 to 1.9, 1.6, and 1.3% for L9, in PR, SC and IM, respectively. The increase in n − 3 PUFA and in total PUFA was similar to that of linolenic acid. The n − 6: n − 3 ratio decreased from 5.7, 5.3 and 5.8 for L0 to 1.8, 1.7 and 2.7 for L9, in PR, SC and IM, respectively. There was no change in the proportion of docosahexaenoic acid with linseed supplementation. The proportions of C18:1 trans -10 and C18:1 trans -11 did not vary in PR, SC and IM with linseed supplementation. The total proportion of trans -octadecenoic acid was high in each tissue type and group of lambs. C18:1 trans -10 represented about half of the total trans -octadecenoic isomers. With an increase in linolenic acid, most cis - and trans -octadecenoic isomers also increased, but trans -10 and trans -11 isomers did not and cis -9 and cis -11 isomers decreased. With linseed supplementation there was a decrease in the Δ9 desaturase indices in SC.

Scientific expertise was developed during a 3-year study to evaluate a large number of bovine female clones (n = 37; from 4 to 36 months of age) and their products through a multidisciplinary approach and compare them to non-cloned breed, age and sex-matched contemporary control animals (n = 38) maintained under the same conditions at the same experimental farm of INRA. In clone and control groups, most parameters measured for health and development of the animals as well as evaluation of milk and meat products were within the normal range for the breed. The strict comparison between cloned animals and controls allowed us to detect slight significant differences between the two groups. Cloned heifers reached puberty significantly later (+62 days) and at higher body weight (+56 kg) than controls. There were slight differences in antigen-specific induced proliferation of lymphocytes after vaccination with ovalbumin before 10 months of age, but responses were normal responses in older animals. There were differences in the fatty acid (FA) composition of milk and muscle arising from two families of clones, suggesting a possible deviation in lipid metabolism as assessed by higher Delta-9 desaturase activity indices in both milk and muscle from clones compared to controls. Nutritional evaluation of milk and meat using the rat model did not reveal any difference between products derived from clones versus controls.

The aim of the study was to investigate the effect of substituting cereals by sugar beet pulp in the feed on the fatty acid (FA) composition of subcutaneous adipose tissue in indoor lambs. Forty-nine male lambs of the Lacaune dairy breed were fed from 23.6 (± 4.1) to 41.0 (± 1.9) kg live weight with hay and a pelleted concentrate containing either 80% of barley and wheat (group C) or 70% sugar beet pulp (group P). The FA composition of caudal adipose tissue sampled at slaughter was determined. The subcutaneous adipose tissue softness was not different between the two groups. The water content and the proportion of odd-numbered (oddFA) and methyl branched-chain FA (BCFA) were high but not significantly different between the two groups (respectively, 22.6% of wet weight, 7.7 and 9.7% of total FA). On the contrary, the proportion of even-numbered saturated FA (ESFA) and especially C18:0 was low but slightly higher in the P group. The proportions of C18:2 and C18:3 were higher in group C than in group P (3.2 vs. 2.2%, P, Effet de la nature de l'énergie ingérée, céréales vs. pulpes de betteraves, sur la composition en acides gras du tissu adipeux caudal d'agneaux de bergerie. L'objectif de ce travail était de mesurer l'incidence de la distribution de pulpes de betteraves en remplacement des graines de céréales dans le régime alimentaire d'agneaux de bergerie sur la composition en acides gras (AG) du tissu adipeux de couverture. Au total, 49 agneaux mâles, de race Lacaune " lait " ont été engraissés de 23,6 (± 4,1) à 41,0 (± 1,9) kg. Ils disposaient en libre accès de foin et d'un aliment concentré aggloméré composé de 80 % d'orge et de blé (lot C) ou de 70 % de pulpe de betterave (lot P). La composition en AG d'un échantillon de tissu adipeux caudal prélevé sur chaque animal lors de l'abattage a été déterminée. L'index de fermeté ne diffère pas significativement entre les 2 groupes. La teneur en eau et la proportion des AG à chaîne carbonée impaire ou ramifiée ont été élevées et non significativement différentes (respectivement, 22,6 % du poids frais, 7,7 et 9,7 % des AG totaux). Inversement, les teneurs en AG saturés pairs et notamment en C18:0 ont été faibles. Les teneurs en C18:2 et C18:3 ont été plus élevées dans le lot C que dans le lot P (3,2 vs. 2,2 %, P

The aim of the present work was to study the relationships between lamb growth performance, soft adipose tissue and fatty acid composition of subcutaneous adipose tissue of intensively reared lambs, and to determine if the occurrence of soft fat, and of odd numbered (Odd FA) and methyl-branched-chain fatty acids in subcutaneous adipose tissue was related to plasma concentrations of methylmalonic acid (MMA). For this purpose, a sensitive gas chromatography assay to measure low plasma concentrations of MMA was developed and validated. In all, 49 male lambs were reared from 23.6 to 41.0 kg. They were fed ad libitum with hay and pelleted concentrates containing either cereals (80%, C) or sugar beet pulp (70%, BP). Plasma concentrations of MMA were measured 12 days before slaughter. Softness score and fatty acid compositions of caudal adipose tissue were determined after slaughter. At the end of the trial, 75% of the carcasses had soft adipose tissue. The occurrence of soft fat appears to be related to high metabolisable energy intake per kg body weight. Soft fat was characterised by a higher water content, a lower proportion of saturated even-numbered fatty acids and higher proportions of Odd FA and methyl-branched-chain fatty acids in caudal adipose tissue, compared to firm fat. Despite high proportions of Odd FA and branched-chain fatty acids in caudal adipose tissue, plasma concentrations of MMA were low (2.02±1.98 μmol/l). No clear relationships between MMA concentrations and soft fat or the proportions of branched-chain fatty acids other than the Iso and Anteiso acids was observed. It was concluded that the present study does not support the hypothesis that the liver’s capacity to metabolise MMA was exceeded.

International audience; The aim of this study was to investigate the effect of substituting wheat and barley by sugar beet pulp on the quality of subcutaneous adipose tissue of intensively reared lambs. Rumen fermentation and methylmalonate plasma concentration, both considered as indicators of lamb metabolism, were also studied. Forty-nine male lambs of the Lacaune dairy breed were fed from 23.6 ($\pm$ 4.1) kg to 41.0 ($\pm$ 1.9) kg live weight with hay and a pelleted concentrate containing either wheat and barley (80% , group C) or sugar beet pulp (70% , group P). Rumen fluid samples were collected at 0, 1, 2, 4 or 6 hours after the last meal before slaughter from 5 lambs per diet at each time. The plasma concentration of methylmalonate was measured in two samples per lamb collected 12 and 36 d before slaughter. The calculated metabolisable energy intake and average daily gain were not significantly different between group C and P (3.27 mcal$\cdot$d$^{-1}$ and 309 g$\cdot$d$^{-1}$). Six hours after the last meal, the rumen concentration of total volatile fatty acids was higher in group C than in group P (186 vs. 137 mmol$\cdot$L$^{-1}$, $P < 0.01$) and the acetate/propionate ratio was lower (0.91 vs. 2.07, $P < 0.01$). The average concentration of methylmalonate in plasma was higher in group C than in group P (2.76 vs. 1.92 $\mu$mol$\cdot$L$^{-1}$, $P = 0.09$). However, the diet had no significant effects on the firmness and colour of subcutaneous adipose tissue; globally, the quality was poor. No relationship between plasma concentration of methylmalonate and fat firmness scores was observed.; Effet de la nature de l'aliment concentré, céréales vs. pulpes de betteraves, sur les fermentations ruminales, la concentration plasmatique en méthylmalonate et la qualité des gras de couverture d'agneaux de bergerie. Le but de ce travail était de vérifier l'effet de l'introduction de pulpes de betteraves dans le régime sur la qualité du gras de couverture des agneaux de bergerie, en s'intéressant plus particulièrement aux fermentations ruminales et aux concentrations plasmatiques en méthylmalonate, pris comme critères d'estimation du métabolisme des agneaux. Ainsi, 49 agneaux mâles, de race Lacaune "lait " , ont été engraissés de 23,6 ($\pm$ 4,1) à 41,0 ($\pm$ 1,9) kg. Ils disposaient en libre accès de foin et d'un aliment concentré aggloméré composé de 80 % de céréales (lot C) ou de 70 % de pulpes de betteraves (lot P). Des échantillons de jus de rumen ont été prélevés lors de l'abattage, 0, 1, 2, 4 ou 6 heures après la distribution du dernier repas, sur en moyenne 5 agneaux par temps et par régime. La concentration plasmatique en méthylmalonate a été mesurée sur 2 prélèvements effectués 12 et 36 jours avant abattage. L'ingestion d'énergie métabolisable calculée et la vitesse de croissance n'ont pas été significativement différentes sur la période de finition (3,27 mcal$\cdot$j$^{-1}$ et 309 g$\cdot$j$^{-1}$). Six heures après le début du repas, les concentrations ruminales en acides gras volatils totaux ont été plus élevées dans le lot C que dans le lot P (186 vs. 137 mmol$\cdot$L$^{-1}$, $p < 0,01$) et le rapport acétate/propionate plus faible (0,91 vs. 2,07, $p < 0,01$). Les concentrations plasmatiques moyennes en méthylmalonate du lot C ont été supérieures à celles du lot P (2,76 vs. 1,92 $\mu$mol$\cdot$L$^{-1}$, $p = 0,09$). Cependant, aucune influence significative du régime n'a été observée sur la fermeté et la couleur du gras sous-cutané ; la qualité des gras n'a été satisfaisante dans aucun des deux lots. Par ailleurs, aucune liaison n'a été mise en évidence entre les notes de fermeté du gras et les concentrations plasmatiques en méthylmalonate.

The aim of the present trial was to study the effect of dietary propionate supplementation on growth performance, intake patterns and on the proportion of odd-numbered and methyl-branched chain fatty acids in internal or in subcutaneous adipose tissues. These fatty acids are responsible, in part, for abnormally soft subcutaneous adipose tissue. Eleven male lambs were fed ad libitum carbohydrate-rich diets based mainly on barley, supplemented (P diet) or not supplemented (C diet) with 5.6% DM of sodium propionate. During the trial, the intake patterns were recorded on three non-consecutive days over a 9h-period. The fatty acid compositions of four adipose tissue sites, two subcutaneous (dorsal, caudal) and two internal (omental, perirenal) were analysed. The ME intake (3.32+/-0.44Mcal per day) and average daily gain (316+/-64g per day) were not different (P>0.10) between the C and P treatments. The intake patterns of these lambs given ad libitum access to feed did not show any large meal even after the morning distribution of feed. No differences in intake patterns were observed between the two diets. The dietary propionate supplementation increased (P

Partie 2 - Déterminants alimentaires et non alimentaires en élevage de la qualité des produits (Chapitre 7); National audience

Partie 2 - Déterminants alimentaires et non alimentaires en élevage de la qualité des produits (Chapitre 5); National audience

Partie 2 - Déterminants alimentaires et non alimentaires en élevage de la qualité des produits (Chapitre 7); National audience

Partie 2 - Déterminants alimentaires et non alimentaires en élevage de la qualité des produits (Chapitre 4); National audience

Partie 3 - Qualité des produits animaux et attente des consommateurs : intégration du volet alimentation et mise en oeuvre par les acteurs des filières (Chapitre 12); National audience

Partie 2 - Déterminants alimentaires et non alimentaires en élevage de la qualité des produits (Chapitre 7); National audience

Partie 2 - Déterminants alimentaires et non alimentaires en élevage de la qualité des produits (Chapitre 7); National audience

Partie 3 - Qualité des produits animaux et attente des consommateurs : intégration du volet alimentation et mise en oeuvre par les acteurs des filières (Chapitre 13)

Partie 2 - Déterminants alimentaires et non alimentaires en élevage de la qualité des produits (Chapitre 7); National audience

Partie 1 - Alimentation animale, formulation des régimes et réglementation (Chapitre 3); National audience

Partie 2 - Déterminants alimentaires et non alimentaires en élevage de la qualité des produits (Chapitre 9); National audience

Partie 1 - Alimentation animale, formulation des régimes et réglementation (Chapitre 2); National audience

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Partie 1 - Alimentation animale, formulation des régimes et réglementation (Chapitre 1); National audience

Partie 2 - Déterminants alimentaires et non alimentaires en élevage de la qualité des produits (Chapitre 6); National audience