Infertility in small ruminants remains an obstacle quite striking and is a major handicap for the improvement of zootechnical parameters in females made reproduction; the case is very spectacular to marginalized areas in North East Africa (steppes) or plant cover is quite small leads the animal to traverse large distances in search of food more rigorous weather conditions , why the animal performance is still quite small compared to those obtained by precision farming, note that among those parameters whose indices are low, the striking example is fertility in females made reproduction leads to low weight performance.
Unfortunately to date we did not yet quantified accurately in Algerian conditions what is related to genetic potential and what is related to environmental variations. Concerning reproduction performances of local sheep, including fertility outputs, many researches, that have to be realized in optimal conditions, are needed to serve as reference. However, in other breeds, all the factors that could affect production and reproduction are well known. You can start by reading the two reviews below.
Genetic aspects of reproduction in sheep. Notter DR. Reprod Domest Anim. 2008 Jul;43 Suppl 2:122-8. doi: 10.1111/j.1439-0531.2008.01151.x. Review.
Aspects of reproductive performance in small ruminants--opportunities and challenges.Hanrahan JP.Reprod Suppl. 2003;61:15-Review.
Parmi les facteurs forts limitants de la fertilité chez le mouton on peu citer la balance énergétique de la brebis (positive ou négative), étant donnée que les brebis suitées en système pastorale extensif sont souvent en déficit énergétique; la brebis ne peut revenir en cyclicité qu'après avoir récupérer ses réserves corporelles. D'autre part, la présence des agneaux sous leurs mères, durant de longues périodes (sevrage tardif), serait un second facteur important vu l’effet négatif de l'allaitement sur la cyclicité de la brebis. En fin, il est très important de connaître les variations pondérales des brebis ( de la mise bas jusqu'au sevrage) en relation avec le potentiel laitier des femelles pour pouvoir établir un trouble de la fertilité!
