Ovulation rate and early embryonic survival rate in female rabbits of a synthetic line and a local Algerian population

[EN] A higher litter size at birth has been reported in female rabbits from a Synthetic line than in those of the Local Algerian population. The aim of this work was to analyse whether this difference in litter size was due to a higher ovulation rate and/or embryonic survival rate in Synthetic line than in Local Algerian population. In total, 24 multiparous female rabbits from Synthetic line and 23 from Local population were used in this experiment. Litter size at birth was recorded up to the first 3 parities. Litter size was 20% higher in Synthetic line than Local population. At their 4th gestation, the females were euthanized at 72 h post coitum. Synthetic line females had 50% more ova and embryos than those of Local population (+4.42 ova and +3.92 embryos, respectively). Synthetic line displayed a lower percentage of normal embryos and a larger number of unfertilized oocytes than Local population (–2.81% and +0.64 oocytes, respectively), but differences were not relevant. Synthetic line showed a lesser embryonic stage of development at 72 h post coitum, showing a higher percentage of early morulae (31.50 vs. 8.50%) and a lower percentage of compact morulae (51.45 vs. 78.65%) than Local population. No relevant difference was found for early embryonic survival rate between Synthetic line and Local population. In conclusion, the difference in litter size was mainly due to a higher ovulation rate in the Synthetic line, allowing more embryos to develop in this line.Belabbas, R.; García, M.; Ainbaziz, H.; Berbar, A.; Zitouni, G.; Lafri, M.; Bouzouan, M.... (2016). Ovulation rate and early embryonic survival rate in female rabbits of a synthetic line and a local Algerian population. World Rabbit Science. 24(4):275-282. doi:10.4995/wrs.2016.5301.SWORD275282244Argente, M. J., Santacreu, M. A., Climent, A., & Blasco, A. (2003). Relationships between uterine and fetal traits in rabbits selected on uterine capacity1. Journal of Animal Science, 81(5), 1265-1273. doi:10.2527/2003.8151265xBelabbas R., AinBaziz H., Ilès I., Zenia S., Boumahdi Z., Boulbina I., Temim S. 2011. Study of prolificacy and its main biological components in rabbits of local Algerian population (Oryctolagus cuniculus). Livest. Res. Rur. Dev., 23: 61.Brun J.M., Baselga M. 2004. Analysis of reproductive performances during the formation of a rabbit synthetic strain. In Proc.: 8th World Rabbit Congress, September 7-10, 2004, Puebla, Mexico, 32-37.Bolet, G., & Theau-Clément, M. (1994). Fertilisation rate and preimplantation embryonic development in two rabbit strains of different fecundity, in purebreeding and crossbreeding. Animal Reproduction Science, 36(1-2), 153-162. doi:10.1016/0378-4320(94)90062-0Buhi, W. C., & Alvarez, I. M. (2003). Identification, characterization and localization of three proteins expressed by the porcine oviduct. Theriogenology, 60(2), 225-238. doi:10.1016/s0093-691x(03)00027-xGacem M., Lebas F. 2000. Rabbit husbandry in Algeria. Technical structure and evaluation of performances. World Rabbit Sci., 8(Suppl. 1): B75-80.Gacem M., Zerrouki N., Lebas F., Bolet G., 2008. Strategy of developing rabbit meat in Algeria: creation and selection of a synthetic strain. In Proc.: 9th World Rabbit Congress, June 10-13, 2008, Verona, Italy, 85-89.Nancarrow C.D., Hill J.L. 1995. Oviduct proteins in fertilization and early embryo development. J. Reprod. Fertil., (Suppl) 49: 3-13.Salvetti P., Guérin P., Theau-Clément M., Hurtaud J., Beckers J.F., Joly T. 2007. Essais d'amélioration de la production d'embryons chez la lapine. In Proc.: 12èmes Journées de la Recherche Cunicole, 27-28 Novembre 2007, Le Mans, France, 41-44.Xie, S., Broermann, D. M., Nephew, K. P., Bishop, M. D., & Pope, W. F. (1990). Relationship between oocyte maturation and fertilization on zygotic diversity in swine. Journal of Animal Science, 68(7), 2027. doi:10.2527/1990.6872027xYoussef Y.K., Iraqi M.M., El-Raffa A.M., Afifi E.A., Khalil M.H., García M.L., Baselga M. 2008. A joint project to synthesize new lines of rabbits in Egypt and Saudi Arabia: emphasis for results and prospects. In Proc.: 9th World Rabbit Congress, June 10-13, 2008, Verona, Italy, 1637-1642

Inference of breed structure in farm animals: Empirical comparison between snp and microsatellite performance

Knowledge of population structure is essential to improve the management and conservation of farm animal genetic resources. Microsatellites, which have long been popular for this type of analysis, are more and more neglected in favor of whole-genome single nucleotide polymorphism (SNP) chips that are now available for the main farmed animal species. In this study, we compared genetic patterns derived from microsatellites to that inferred by SNPs, considering three pairs of datasets of sheep and cattle. Population genetic differentiation analyses (Fixation index, FST ), as well as STRUCTURE analyses showed a very strong consistency between the two types of markers. Microsatellites gave pictures that were largely concordant with SNPs, although less accurate. The best concordance was found in the most complex dataset, which included 17 French sheep breeds (with a Pearson correlation coefficient of 0.95 considering the 136 values of pairwise FST, obtained with both types of markers). The use of microsatellites reduces the cost and the related analyses do not require specific computer equipment (i.e., information technology (IT) infrastructure able to provide adequate computing and storage capacity). Therefore, this tool may still be a very appropriate solution to evaluate, in a first stage, the general state of livestock at national scales. At a time when local breeds are disappearing at an alarming rate, it is urgent to improve our knowledge of them, in particular by promoting tools accessible to the greatest number

EFFET DES TRAITEMENTS HORMONAUX SUR LES PARAMETRES DE REPRODUCTION CHEZ DES BREBIS «OULED-DJELLAL»

L’induction et la synchronisation des chaleurs par des éponges vaginales de FGA, constituent le moyen d’atteindre une homogénéisation d’un troupeau ovin. La stimulation ovarienne, au retrait des éponges, par la PMSG permettrait d’améliorer les taux de la fertilité, de la fécondité et de la prolificité. Pour atteindre ces objectifs, nous avons effectué une étude sur 100 brebis de race"Ouled Djellal". L’induction du part représente également une technique qui permet aussi l’homogénéisation du troupeau. Pour cela, nous avons utilisé une étude d’induction d’agnelage par 3 produits différents sur 80 brebis issues de la première partie de l’étude, qui ont été réparties en 4 lots renfermant chacun 20 brebis. Tous les traitements ont été effectués à 145 jours de gestation. Le lot I a été pris comme témoin, n’a subit aucun traitement, le lot II a subit un traitement par la dexaméthasone, le lot III a subit un traitement au benzoate d’oestradiol et enfin le lot IV a subit un traitement par la prostaglandine (PGF2α). Les résultats obtenus ont montré que la dose de 500 UI de la PMSG a permis l’obtention d’une stimulation maximale des ovaires, ce qui nous a permis d’enregistrer des taux de fertilité de 75±10 %, des taux de fécondité de 130±11.55% et des taux de prolificité de 175±20.41%. Nous avons enregistré des intervalles de temps moyens traitement-agnelage de 43.45±17 heures, 28.95±4.66 heures, 146.95±39.98 heures et de 124.75±44.88 heures avec la dexaméthasone, le benzoate d’oestradiol, PGF2α, et le lot témoin respectivement. Le benzoate d’oestradiol et la dexaméthasone ont réduit efficacement la durée de gestation, alors que la PGF2α n’a pas eu cet effet du fait que l’intervalle enregistré est plus proche de celui du lot témoin. L’ensemble des produits utilisés n’a pas présenté d’effets indésirables sur les brebis et leurs progénitures. Sauf quelques effets de rétention placentaire, au delà de 4 heures post-partum, avec le benzoate d’oestradiol dont nous avons enregistré un taux de 25%. Ces techniques permettent donc une bonne homogénéisation du produit des troupeaux et l’amélioration des performances de reproduction avec des charges abordables aux éleveurs

Seasonal distribution of Rickettsia spp. in ticks in northeast Algeria

This article discusses research conducted on the sampling of two tick species: Ixodes ricinus and Rhipicephalus bursa. Ticks were collected in northern Algeria (El Tarf) in 2014 and studied for differences in abundance and seasonal distribution of population dynamics, as well as tested by PCR for the presence of Rickettsia spp. By molecular tools, four Rickettsia pathogens agents were detected: R. helvetica, R. monacensis, R. raoultii and R. massiliae. Keywords: Algeria, Ixodes, PCR, Rhipicephalus, Rickettsia, tick

Phenotypic characterization of the major sheep breed in Algeria

International audienceNorth Africa represents a livestock biodiversity hotspot with breeds that have evolved in conditions as harsh as varied. In Algeria, among the eight major sheep breeds, the Ouled-Djellal receives the preference of most farmers thanks to its reputation of best meaty breed. In this study, the phenotypic variability of the Ouled-Djellal was investigated taking into account the multiplicity of management practices and environments, using multivariate discriminant analysis, as recommended by the Food and Agriculture Organization (FAO). A total of 1104 females and 84 males were sampled in a large area including the cradle of the breed, with 18 quantitative measures (20 for males) and 14 qualitative traits. This study provides the first fine phenotypic characterization of an Algerian breed. Moreover, two patterns of phenotypic structuration were highlighted (i) the four regions sampled were clearly discriminated; hence the use of main markets in each region induced gene flows mostly restricted within the boundaries of the region (ii) sheep reared in altitude showed lower conformation than sheep reared in plains; hence our results postulated that high plateaus are not optimum production environment for Ouled-Djellal. Some local breeds are highly adapted to specific harsh environments encountered in the Algeria; the spread of the Ouled-Djellal in the country, without regard of production environment characteristics, represents a danger for most of the other breeds progressively abandoned or genetically diluted with the Ouled-Djellal because of crossbreeding practices

Inventory and update on argasid ticks and associated pathogens in Algeria

International audienc

Seroprevalence of West Nile virus antibodies in equids in the North-East of Algeria and detection of virus circulation in 2014

International audienceWest Nile fever (WNF) is a viral disease of wild birds transmitted by mosquitoes. Humans and equids can also be affected and suffer from meningoencephalitis. In Algeria, since the 1994 epidemic, no data on WNV circulation was available until 2012. In September 2012, a fatal human case of WNV neuro-invasive infection occurred in Jijel province. This study describes the first seroprevalence study of West Nile virus (WNV) antibodies conducted in the equine population in Algeria. During 2014, serum samples were collected from 293 equids (222 donkeys and 71 horses) asymptomatic and unvaccinated for WNV in three localities in Northeastern wetlands of Algeria. Antibodies against WNV were found in 51 samples (seroprevalence 17.4%) of sampled equids, distributed as follows: 19 (seroprevalence 26.8%) horses and 32 (seroprevalence 14.4%) donkeys. Moreover 7 horses coming from Blida, in the center of Algeria, were tested before and after an 8-months stay in North-East Algeria. We observe a seroconversion in 2 horses, showing WNV circulation in 2014 in this specific region of Algeria. (C) 2016 Published by Elsevier Ltd

Genome-wide analysis highlights genetic dilution in Algerian sheep

International audienceAlgeria represents a reservoir of genetic diversity with local sheep breeds adapted to a large range of environments and showing specific features necessary to deal with harsh conditions. This remarkable diversity results from the traditional management of dryland by pastoralists over centuries. Most of these breeds are poorly productive, and the economic pressure leads farmers to realize anarchic cross-breeding (that is, not carried out in the framework of selection plans) with the hope to increase animal's conformation. In this study, eight of the nine local Algerian sheep breeds (D'men, Hamra, Ouled-Djellal, Rembi, Sidaoun, Tazegzawt, Berber and Barbarine) were investigated for the first time by genome-wide single-nucleotide polymorphism genotyping. At an international scale, Algerian sheep occupied an original position shaped by relations with African and European (particularly Italian) breeds. The strong genetic proximity with Caribbean and Brazilian breeds confirmed that the genetic make-up of these American breeds was largely influenced by the Atlantic slave trade. At a national scale, an alarming genetic dilution of the Berber (a primitive breed) and the Rembi was observed, as a consequence of uncontrolled mating practices with Ouled-Djellal. A similar, though less pronounced, phenomenon was also detected for the Barbarine, another ancestral breed. Genetic originality appeared to be better preserved in Tazegzawt, Hamra, D'men and Sidaoun. These breeds should be given high priority in the establishment of conservation plans to halt their progressive loss. For Berber and Barbarine that also occur in the bordering neighbor countries, urgent concerted transnational actions are needed