Ram Reproduction

Producers often forget that the ram contributes 50% of the genetic makeup of offspring, affecting not only production traits (birth weight, average daily gain), but also the reproductive traits of potential flock replacements (semen production, ovulation rate, onset of puberty, seasonality).

The ram should be given special attention throughout the year, but especially in preparation for and during the breeding season. A veterinarian or owner who is prepared to perform a breeding soundness examination (BSE), who is knowledgeable of ram diseases, and who can make recommendations and/or decisions on ram management, can provide valuable service and input to sheep pro-ducers.[3]

A breeding soundness exam includes visual appraisal of general health and body condition, as well as a soundness check on feet, legs, eyes, jaws, and dentition. A scrotal circumference measurement is taken, along with palpation of the testicles. The testicles should palpate firm, but not hard, having no signs of abscesses, injuries, orchitis, or any other condition that could affect fertility. The penis and sheath should be examined for posthitis (pizzle rot), ulcerative dermatosis, adhesions, or injury (including shearing trauma). Often, a blood sample is collected during the BSE in order to conduct a serological test for ovine sexually transmitted diseases, i.e., Brucella ovis. Semen samples are collected usually by electro-ejaculation and analyzed microscopically for color, percent live cells, percent motility, and percent abnormal spermatozoa. Upon palpating the scrotum, both testicles should be fully descended into the scrotal sack. At this time, a measurement is taken of the scrotum at the point of the greatest circumference, and available standard guidelines for these dimensions should be utilized. Research has shown that daughters from sires with larger testicle circumferences have higher pregnancy rates than females sired by males with smaller circumferences. Breeding soundness exam results apply only on the day the exam was conducted. Rams may be designated satisfactory, temporarily unsatisfactory, or unsatisfactory. Temporarily unsatisfactory rams may be examined again after an appropriate time, depending on the abnormality. Unsatisfactory breeders, with permanent testicular abnormalities, serological positive for B. ovis, scrotal hernia, sterility, etc. should be culled.[3]

Rams should be maintained separately from ewes except when breeding. The breeder rams should be sorted by age classification, i.e., virgin rams separated from mature and previously utilized breeding rams. This will reduce possible exposure to B. ovis from undetected, infected older rams.

Teaser rams are used to advance the breeding season, synchronize estrus in ewes, and detect the return to estrus in nonpregnant ewes. Prior to being surgically altered (vasectomy or epididymectomy), teaser rams should be carefully selected for libido and preferably chosen from breeds with an extended breeding season (Dorset, Finnish Landrace, Polypay). Teasers will breed ewes, and therefore, should be free of venereally transmitted diseases.

Artificial insemination of sheep, although not as widely practiced as in the dairy and beef cattle industries, is used in the purebred sector of the domestic sheep industry. Newer assisted reproduction technologies are being developed that will enhance the use of AI in the sheep industry.

Pregnancy Guide

Pregnancy Guide

A Beginner's Guide to Healthy Pregnancy. If you suspect, or know, that you are pregnant, we ho pe you have already visited your doctor. Presuming that you have confirmed your suspicions and that this is your first child, or that you wish to take better care of yourself d uring pregnancy than you did during your other pregnancies; you have come to the right place.

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