Agroecology uses natural processes and local resources rather than chemical inputs to ensure production while limiting the environmental footprint of livestock and crop production systems. Selecting to achieve a maximization of target production criteria has long proved detrimental to fitness traits. However, since the 1990s, developments in animal breeding have also focussed on animal robustness by balancing production and functional traits within overall breeding goals. We discuss here how an agroecological perspective should further shift breeding goals towards functional traits rather than production traits. Breeding for robustness aims to promote individual adaptive capacities by considering diverse selection criteria which include reproduction, animal health and welfare, and adaptation to rough feed resources, a warm climate or fluctuating environmental conditions. It requires the consideration of genotype × environment interactions in the prediction of breeding values. Animal performance must be evaluated in low-input systems in order to select those animals that are adapted to limiting conditions, including feed and water availability, climate variations and diseases. Finally, we argue that there is no single agroecological animal type, but animals with a variety of profiles that can meet the expectations of agroecology. The standardization of both animals and breeding conditions indeed appears contradictory to the agroecological paradigm that calls for an adaptation of animals to local opportunities and constraints in weakly artificialized systems tied to their physical environment.

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Agroecology uses ecological processes and local resources rather than chemical inputs to develop productive and resilient livestock and crop production systems. In this context, breeding innovations are necessary to obtain animals that are both productive and adapted to a broad range of local contexts and diversity of systems. Breeding strategies to promote agroecological systems are similar for different animal species. However, current practices differ regarding the breeding of ruminants, pigs and poultry. Ruminant breeding is still an open system where farmers continue to choose their own breeds and strategies. Conversely, pig and poultry breeding is more or less the exclusive domain of international breeding companies which supply farmers with hybrid animals. Innovations in breeding strategies must therefore be adapted to the different species. In developed countries, reorienting current breeding programmes seems to be more effective than developing programmes dedicated to agroecological systems that will struggle to be really effective because of the small size of the populations currently concerned by such systems. Particular attention needs to be paid to determining the respective usefulness of cross-breeding v. straight breeding strategies of welladapted local breeds. While cross-breeding may offer some immediate benefits in terms of improving certain traits that enable the animals to adapt well to local environmental conditions, it may be difficult to sustain these benefits in the longer term and could also induce an important loss of genetic diversity if the initial pure-bred populations are no longer produced. As well as supporting the value of within-breed diversity, we must preserve between-breed diversity in order to maintain numerous options for adaptation to a variety of production environments and contexts. This may involve specific public policies to maintain and characterize local breeds (in terms of both phenotypes and genotypes), which could be used more effectively if they benefited from the scientific and technical resources currently available for more common breeds. Last but not least, public policies need to enable improved information concerning the genetic resources and breeding tools available for the agroecological management of livestock production systems, and facilitate its assimilation by farmers and farm technicians.Keywords: agroecology, livestock, cross-breeding, local breed, breeding scheme ImplicationsTo promote transition towards agroecological systems, a major concern is the need to develop breeding strategies that will ensure sufficient diversity within and across breeds and encourage the use of breeds with characteristics that are well adapted to local and sustainable animal production. Breeding programmes in all livestock sectors need to evolve so that larger numbers of diverse and complementary genotypes become available to fit the full range of environmental conditions and production systems. In addition, the performance of animals from local breeds and cross-bred po...

Dans l’ouest du Burkina Faso, des laiteries se heurtent à un problème d’approvisionnement en lait local, car la production est faible, saisonnée, atomisée et coûteuse à collecter. Cette étude a eu pour objectif d’identifier des leviers pour augmenter la production et réduire la saisonnalité. Elle a été réalisée chez 18 polyculteurs-éleveurs de la région des Hauts-Bassins impliqués dans la production de lait. Une analyse multivariée basée sur des variables de structures, de fonctionnement et de performance des exploitations a permis d’identifier cinq types de polyculteurs-éleveurs impliqués dans cette production : « les allaitants » à faible niveau d’intrants et à orientation pastorale à grands effectifs de vaches (T1), à effectifs moyens (T2) ; les allaitants à orientation agropastorale (T3) ; les laitiers spécialisés et à visée commerciale ayant peu recours aux fourrages verts (T4), ou à forte utilisation de fourrage vert (T5). Les types T1 et T2 se caractérisaient par une alimentation quasi exclusive au pâturage en toute saison, et un niveau de production de lait inférieur à deux litres par vache par jour au pic de lactation. Le lait issu de ces exploitations était faiblement commercialisé et rarement vendu aux laiteries. Les types T3 ont davantage eu recours aux fourrages secs et aux aliments, ce qui leur a permis d’améliorer leur production de lait commercialisée fréquemment en laiterie (env. 2 L/vache/jour au pic de lactation). Les types T4 et T5 se caractérisaient par un recours à des races améliorées, et une utilisation importante de fourrages et d’aliments achetés toute l’année, leur assurant une production de lait plus élevée (5–13 L/vache/jour au pic de lactation). Ces exploitations vendaient leur lait en totalité à la laiterie. Nos résultats soulignent que la production était fortement pénalisée par une alimentation trop pauvre en aliments et en fourrages de qualité, et que la saisonnalité des mises bas aggravait la chute de production en fin de saison sèche.

This study aimed to evaluate the substitution of imported corn and soybean by local feed resources from tropical production settings such as entire green banana and Gliricidia sepium forage as energy and protein sources, respectively, in sheep diets. Two experiments were conducted: first, a 'growth trial' and second, an in vivo digestion study. In the 'growth trial', 40 Martinik lambs [body weight (BW): 29.4 +/- 3.6 kg; 6 months old) were used and distributed into four groups of 10 lambs each according to treatment: HBGl (banana + gliricidia at low level; 1500 g/day; 119 g/kg BW(0.75)), HBGh (banana + gliricidia at high level; 3000 g/day; 238 g/kg BW(0.75)), HBS (banana + soybean cake) and Control (corn + soybean cake). In digestion trial, four Martinik rams (BW: 57.2 +/- 3.45 kg) fitted with ruminal and duodenal cannulae were used; treatments (HBG, HBS and Control) were similar but adjusted to metabolic body weight (MW) and just one level of gliricidia was used. Intake, average daily gain (ADG), feed intake to gain index (F:G), apparent total and ruminal digestibilities as well as nitrogen balance, microbial efficiency and volatile fatty acid (VFA) profile were monitored. Lambs fed HBGh had greater dry matter (DM) intake based on MW and ADG (173 g/day vs. 141 g/day; p < 0.001), whereas HBGl lambs showed the lowest ADG (71.5 g/day) and the worst F:G (14.4; p < 0.001). The DM, organic matter (OM), neutral detergent fibre and acid detergent fibre digestibilities were not influenced by treatment, whereas crude protein digestibility was higher (p = 0.024) in diets offered banana or corn + soybean cake (687 g/kg DM and 658 g/kg DM, respectively). Ruminal DM and OM digestibilities did not differ among treatments. Total or individual VFA concentrations were also not influenced by the diet. Higher (p = 0.006) ruminal fluid pH values were recorded for diets combining banana and gliricidia (6.54) or banana and soybean (6.39) until 3 h after a meal. As all animals on gliricidia- and banana-supplemented diets gained weight and maintained a positive N balance, it is concluded that green banana and gliricidia forage may be a viable alternative to replace conventional energy and protein supplements in sheep diets.

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Digestive effects of diet supplementation with an exogenous fi brolytic enzyme preparation (cellulase and xylanase activities) were evaluated under in vivo and in vitro conditions. Eight lactating Murciano-Granadina dairy goats (four per treatment) were used to measure the total tract digestibility of an ad libitum total mixed ration (forage, 65%; concentrate, 35%) to which the enzyme was, or was not, added to the concentrate. In vitro degradability and gas production were also studied using 2 goats (1 per dietary treatment) as ruminal liquor donors. Dry matter digestibility increased by effect of the enzyme supplemented goats, while digestibilities of organic matter, protein and fi bre fractions did not vary. Differently, in vitro trial showed no differences either in dry matter or fi bre degradabilities or in gas production. In conclusion, supplementing dairy goat concentrate with a fi brolytic enzyme preparation, under our conditions, enhanced in vivo dry and organic matter digestibilities although the effects were not observed in vitro.

Background Among the adaptive capacities of animals, the management of energetic body reserves (BR) through the BR mobilization and accretion processes (BR dynamics, BRD) has become an increasingly valuable attribute for livestock sustainability, allowing animals to cope with more variable environments. BRD has previously been reported to be heritable in ruminants. In the present work, we conducted genome-wide studies (GWAS) in sheep to determine genetic variants associated with BRD. BR (i.e. levels) and BRD (i.e. changes over time) were obtained through body condition score measurements at eight physiological stages throughout each productive cycle in Romane ewes (n = 1034) and were used as phenotypes for GWAS. After quality controls and imputation, 48,593 single nucleotide polymorphisms (SNP) were included in the GWAS. Results Among the 23 QTL regions identified, a major QTL associated with BR during pregnancy and lactation was identified on chromosome 1. In this region, several significant SNPs mapped to the leptin receptor gene (LEPR), among which one SNP mapped to the coding sequence. The point mutation induces the p.P1019S substitution in the cytoplasmic domain, close to tyrosine phosphorylation sites. The frequency of the SNP associated with increased BR levels was 32%, and the LEPR genotype explained up to 5% of the variance of the trait. Higher fatness levels in ewes carrying the LEPR p.P1019S mutation were observed all along the productive cycle. Conclusions These results provide strong evidences for involvement of LEPR in the regulation of BR in sheep and highlight it as a major candidate gene for improving adaptive capacities by genetic selection.