The procedure of somatic cloning is associated with important losses during pregnancy and in the perinatal period, reducing the overall efficacy to less than 5% in most cases. A mean of 30% of the cloned calves die before reaching 6 months of age with a wide range of pathologies, including, for the most common, respiratory failure, abnormal kidney development, liver steatosis. Heart and liver weight in relation to body weight are also increased. Surviving animals, although mostly clinically normal, differ from controls obtained by artificial insemination (AI) within the first 1-2 months, to become undistinguishable from them thereafter. Hemoglobin concentrations, for instance, are lower, and leptin concentrations are elevated. In response to the lack of prospective studies addressing the health of adult clones, a long-term, 3-4-year study is currently being conducted to assess the health of mature bovine clones at INRA. Preliminary results over 1 year of study do not show any statistical difference between groups for hematological parameters.

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.

Contents The aim of this study was to determine whether postpartum variations of plasma IGF‐1 and IGFBP concentrations, oocyte production and quality were related to parity and subsequent conception rate in Holstein dairy cows. Holstein dairy cows [10 primiparous (PP) and 22 multiparous (MP)] were allotted in six batches and sampled once weekly between calving and oestrous synchronization treatment started at 71.2 ± 2.0 days postpartum. During the 3 weeks before treatment, ovum pick‐up (OPU) was performed twice weekly. Oocytes were scored on a 4‐point scale, and oocytes from OPU1, 3 and 5 were fertilized in vitro. Seventeen cows became pregnant after first and second AI and were considered as fertile (F), while the others were considered to be subfertile (SF). Logistic regression was carried out to investigate the relationships between repeated measurements and fertility including parity and batch effects in the models. Likelihood of fertility significantly increased when plasma urea and IGFBP‐3 concentrations decreased and was higher in PP compared with MP cows. There was a trend for fertility to increase when plasma IGF‐1 concentrations increased (p = 0.07). In vitro cleavage and development rates were similar between SF and F cows (46.4% and 28.3% in SF vs 55.0% and 22.1% in F). Parity had an effect on plasma IGF‐1 concentrations (PP: 61.65 ± 2.67 vs MP: 41.63 ± 5.81 ng/ml, p < 0.001), mean number of follicles aspirated per session (PP: 5.7 ± 1.3 vs MP: 9.5 ± 0.8, p < 0.05) and fertility (PP: 8/10 = 80% vs MP: 9/22 = 41%, p < 0.05) but not on the number of oocytes recovered per session nor their quality. In conclusion, postpartum plasma urea and IGFBP‐3 concentrations, but not oocyte production and quality before breeding, were related to subsequent conception rate in our experimental design. Parity had a significant effect on energy status, follicular growth and fertility and needs to be considered when investigating relationships between nutrition and reproduction.

A procedure that uses an original molecular marker (IS200-PCR) and that is based on the amplification of DNA with outward-facing primers complementary to each end of IS200 has been evaluated with a collection of 85 Salmonella enterica subsp. enterica serotype Typhimurium isolates. These strains were isolated from a group of 10 cows at different stages: during transportation between the farm and the slaughterhouse, on the slaughter line, from the environment, and from the final product (ground beef). The 85 isolates were characterized by their antibiotic resistance patterns and were compared by IS200-PCR and by use of four other genotypic markers. Those markers included restriction profiles for 16S and 23S rRNA (ribotypes) and amplification profiles obtained by different approaches: random amplified polymorphic DNA analysis, enterobacterial repetitive intergenic consensus PCR, and PCR ribotyping. The results of the IS200-PCR were in accordance with those of other molecular typing methods for this collection of isolates. Five different genotypes were found, which made it possible to refine the hypotheses on transmission obtained from phenotypic results. The genotyping results indicated the massive contamination of the whole group of animals and of the environment by one clonal strain originally recovered from one cow that excreted the strain. On the other hand, a few animals and their environment appeared to be simultaneously contaminated with genetically different strains.

No abstract

A procedure that uses an original molecular marker (IS200-PCR) and that is based on the amplification of DNA with outward-facing primers complementary to each end of IS200 has been evaluated with a collection of 85 Salmonella enterica subsp. enterica serotype Typhimurium isolates. These strains were isolated from a group of 10 cows at different stages: during transportation between the farm and the slaughterhouse, on the slaughter line, from the environment, and from the final product (ground beef). The 85 isolates were characterized by their antibiotic resistance patterns and were compared by IS200-PCR and by use of four other genotypic markers. Those markers included restriction profiles for 16S and 23S rRNA (ribotypes) and amplification profiles obtained by different approaches: random amplified polymorphic DNA analysis, enterobacterial repetitive intergenic consensus PCR, and PCR ribotyping. The results of the IS200-PCR were in accordance with those of other molecular typing methods for this collection of isolates. Five different genotypes were found, which made it possible to refine the hypotheses on transmission obtained from phenotypic results. The genotyping results indicated the massive contamination of the whole group of animals and of the environment by one clonal strain originally recovered from one cow that excreted the strain. On the other hand, a few animals and their environment appeared to be simultaneously contaminated with genetically different strains.

Neopsora canimum est un protozoaire parasite identifié récemment chez le bétail et les animaux de compagnies. Son cycle est inconnu. Le seul mode de transmission connu est la voie transplacentaire. La néosporose est une cause majeure d'avortements dans de nombreux pays. Cet article présente un cas d'avortements bovins associés à Neospora en France.

Une affection tumorale similaire à la neurofibromatose de l’Homme vient d’être découverte chez le porc. Cette maladie, de caractère génétique dominant, a été retrouvée dans plusieurs élevages sous deux des trois formes rencontrées chez l’Homme, l’une à grosses tumeurs sous-cutanées et l’autre, strictement intradermique. Ces lésions ont été étudiées aux plans clinique et anatomopathologique. Les cellules tumorales ont été mises en culture et le séquençage de leur génome entrepris. Ce travail revêt une importance toute particulière car il n’existait jusqu’alors aucun modèle animal de cette maladie très fréquente chez l’Homme.