Essais de production et de collecte d'embryons chez la vache Somba

Des essais de collecte d'embryons ont été menés dans un troupeau de vaches trypanotolérantes de race Somba, pendant quatre cycles de polyovulation réalisés en différentes saisons. Un progestatif (Norgestomet, Crestar® Intervet) et des gonadotrophines (soit p-FSH Pluset® Serono, soit Folltropin® Vetrepharm) ont été utilisés selon des dosages modifiés en raison du poids des animaux. Les donneuses ont été ensuite fécondées deux fois à 12 heures d'intervalle, par saillie naturelle ou insémination artificielle, la semence de trois taureaux ayant été récoltée et congelée sur place en paillettes. Le taux général de réponse à la polyovulation a été de 72 p. 100. Les embryons ont été collectés à 6,5 jours, au stade de morula compactée ou de jeune blastocyste. Sur l'ensemble des 30 collectes, 87 embryons ont pu être récupérés. Parmi ces embryons, 39 (45 p. 100) appartenaient aux catégories Q1 et Q2 et étaient congelables, 19 (22 p. 100) appartenaient à la catégorie Q3 et les 29 restants (33 p. 100) appartenaient à la catégorie Q4 (non transférables). La production moyenne d'embryons transférables (1,9 par donneuse) n'a pas été affectée significativement par le type de gonadotrophine utilisé, mais le taux d'embryons congelables a été plus élevé en saison humide fraîche qu'en saison humide chaude (respectivement 59 vs 38 p. 100)

Serial analysis of gene expression (SAGE) in bovine trypanotolerance: preliminary results

In Africa, trypanosomosis is a tsetse-transmitted disease which represents the most important constraint to livestock production. Several indigenous West African taurine (Bos taurus) breeds, such as the Longhorn (N'Dama) cattle are well known to control trypanosome infections. This genetic ability named "trypanotolerance" results from various biological mechanisms under multigenic control. The methodologies used so far have not succeeded in identifying the complete pool of genes involved in trypanotolerance. New post genomic biotechnologies such as transcriptome analyses are efficient in characterising the pool of genes involved in the expression of specific biological functions. We used the serial analysis of gene expression (SAGE) technique to construct, from Peripheral Blood Mononuclear Cells of an N'Dama cow, 2 total mRNA transcript libraries, at day 0 of a Trypanosoma congolense experimental infection and at day 10 post-infection, corresponding to the peak of parasitaemia. Bioinformatic comparisons in the bovine genomic databases allowed the identification of 187 up- and down- regulated genes, EST and unknown functional genes. Identification of the genes involved in trypanotolerance will allow to set up specific microarray sets for further metabolic and pharmacological studies and to design field marker-assisted selection by introgression programmes

Selection assisted by a BoLA-DR/DQ haplotype against susceptibility to bovine dermatophilosis

Bovine dermatophilosis is a severe skin infection of tropical ruminants inducing a severe loss in productivity and a 15% mortality rate. This disease is caused by the actinomycete bacterium Dermatophilus congolensis associated with the tick Amblyomma variegatum. Currently there are no prospects for a vaccine, and acaricide or antibiotic control is hampered by the development of chemoresistance. Animal breeders have observed that dermatophilosis susceptibility seems to be determined genetically, and we previously identified a BoLA-DRB3-DQB class II haplotype marker for high (R2 = 0.96) susceptibility to the disease. With this marker, we developed a successful eugenic selection procedure for zebu Brahman cattle in Martinique (FWI). Over a period of five years, a marked reduction in disease prevalence, from 0.76 to 0.02 was achieved, and this low level has been maintained over the last two years. The selection procedure, based on a genetic marker system targeting the highly polymorphic BoLA locus, eliminates only those individuals which are at the highest risk of contracting the disease. In the present work, we discuss the properties of this system, including the "heterozygote advantage" and the "frequency dependence" theories, and examine their involvement in the biological mechanisms at the host/pathogen interface. We speculate on the exact role of the MHC molecules in the control of the disease, how the natural selection pressure imposed by the pathogens selectively maintains MHC diversity, and how our results can be practically applied for integrated control of dermatophilosis in developing countries

Gaps and opportunities for the integrated delivery of mother-child care, postpartum family planning and nutrition services in Burkina Faso, Côte d'Ivoire and Niger

# Background Maternal and infant deaths can be prevented through integrated service delivery during pregnancy, postpartum, and early childhood. Our study analyses the gaps and opportunities associated with integrating maternal, newborn, and child health (MNCH) services with postpartum family planning (PPFP) and nutrition services at different points of contact in health facilities in a preintervention context in west Africa. # Methods We conducted a qualitative study from June to July 2018 in Burkina Faso, Côte d'Ivoire and Niger. The points of contact studied at the health facility level were the prenatal care, postpartum care and immunisation/growth monitoring services. Individual in-depth interviews were used to collect data from key informants (providers, community health workers and mother-child health programme managers). To measure the degree of service integration, we used the dimensions and indicators included in the Integra Initiative framework concerning four aspects of integration: physical (the availability of multiple services in the health facility), temporal (the availability of care more than one day per week), provider level, and functional (the receipt of integrated services by the client). # Results The findings of this study show that the integrated delivery of MNCH, PPFP, and nutrition services is configured in similar ways in Burkina Faso, Côte d'Ivoire and Niger and is insufficient at all points of contact. Physical integration is high. However, the study found important gaps in temporal, functional and provider-level integration. The main barriers to integrated service delivery are the shortage of providers, the lack of training in integrated service delivery, and insufficient service organisation. However, the availability of multiple services throughout the week, the multiple points of contact between the mother-child pair and the health system, and the multiple skills of providers represent opportunities for functional integration through the establishment of a formal referral system between the different care units with follow-up and feedback among service providers. # Conclusions The provision of training and the development of a well-organised referral system in different health facilities, taking into account the specific characteristics of each health facility (urban/rural, primary health facility/district hospital), can improve the delivery of integrated MNCH, PPFP, and nutrition care to the mother-child pair

Serial analysis of gene expression (SAGE) in bovine trypanotolerance: preliminary results

In Africa, trypanosomosis is a tsetse-transmitted disease which represents the most important constraint to livestock production. Several indigenous West African taurine Bos taurus) breeds, such as the Longhorn (N'Dama) cattle are well known to control trypanosome infections. This genetic ability named “trypanotolerance” results from various biological mechanisms under multigenic control. The methodologies used so far have not succeeded in identifying the complete pool of genes involved in trypanotolerance. New post genomic biotechnologies such as transcriptome analyses are efficient in characterising the pool of genes involved in the expression of specific biological functions. We used the serial analysis of gene expression (SAGE) technique to construct, from Peripheral Blood Mononuclear Cells of an N'Dama cow, 2 total mRNA transcript libraries, at day 0 of a Trypanosoma congolense experimental infection and at day 10 post-infection, corresponding to the peak of parasitaemia. Bioinformatic comparisons in the bovine genomic databases allowed the identification of 187 up- and down- regulated genes, EST and unknown functional genes. Identification of the genes involved in trypanotolerance will allow to set up specific microarray sets for further metabolic and pharmacological studies and to design field marker-assisted selection by introgression programmes