Bovine Reproduction. Группа авторов

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Bovine Reproduction - Группа авторов


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circumference of two year old bulls of several beef breeds. Theriogenology 27: 485–491.

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       Mike Thompson1 and James Alexander2

       1 Willow Bend Animal Clinic, Holly Springs, MS, USA

       2 Alexander Veterinary Services, Bentonia, MS, USA

      When a bull breeding soundness examination (BBSE) is performed for the purpose of evaluating a bull's potential to breed in a natural service situation, the physical component takes on paramount significance. In fact, as soon as any physical abnormality that would impede natural service is observed, or the bull does not meet the minimum standards for scrotal circumference (SC), the examination need not proceed to evaluation of semen characteristics. Thus, goals of the physical examination portion of a BBSE are the identification of undesirable genetic traits, structural or physical impediments to breeding, and pathology of the reproductive tract. Even though it is common for inadequacies to exist in this area of the BBSE, it is often ignored or rushed through without attention to detail or in a consistent systematic manner. Therefore it is of utmost importance that the physical examination be done using a consistent protocol. Additionally, the SC, which is an indirect metric for testicle size and thus sperm production potential, must be measured and meet minimum standards.

      The history can be addressed prior to or during the physical examination. The history can provide the examiner with insight into genetics, condition, management, vaccination, any disease testing programs, and history of disease in the herd. The breed or breed composition should be obtained to help establish what genetic abnormalities or which conformation traits, maturity rates, and age of puberty may be common to that breed. The ration fed previously and at present should be established as well as the level of each ingredient in the rations and the poundage fed to each bull. The veterinarian needs to determine what body condition scores were attained at different stages of development. Management practices should be established with regard to large or small group facilities, parasite control, pasture or dry lot, through space, and water availability. These management practices can influence the level of foot problems and increased incidence of diseases such as vesiculitis. The herd vaccination program should be ascertained, if for no other reason than for buyer information. Information on disease control programs should be established for buyer information and the reason for those programs. The history of disease in the herd may explain the results of the BBSE examination and again be useful information to the herd owner and/or buyer.

      For a bull to survive and function as a natural service sire (pasture or range environment), he must be able to walk, eat, see, and bear weight on his back legs. Thus, a basic examination should begin with a history, examination at a distance, and an assessment of a bull's conformation, gait, and overall appearance.

      Examination at a Distance

      Conformation

Photo depicts a three-year-old Angus bull that exhibits the screw claw abnormality. This bull will require annual hoof trimming to remain sound.

      Examination Close Up

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