Equine Reproductive Procedures. Группа авторов. Читать онлайн. Newlib. NEWLIB.NET

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Издательство: John Wiley & Sons Limited
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Жанр произведения: Биология
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isbn: 9781119555933
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(i.e., teasing behavior).

Abbreviation Levels: Option 1 Levels: Option 2 Behavior
H + +++ In heat
O Out of heat
H/O +/– ++ Coming into or going out of heat
I + Indifferent

      Silent Estrus

      Maiden mares may not show heat well and foaling mares may not show heat at all unless the foal is restrained and/or safely away from the stallion. Subordinate mares may be inhibited from expressing estrus in the presence of a dominant mare. In addition, a mare may have a preference for, or an aversion toward, an individual stallion. Mares with “silent estrus” may have lower concentrations of estradiol 17 β than mares expressing normal estrus.

      There are many systems used for teasing mares, including chutes, rails, fences, pens, and paddocks. Keys to successful teasing are patience, persistence, and knowing the behavioral characteristics of each mare. Consequently, it is advantageous for the same individual(s) to tease mares each day, so that slight variations in individual responses can be recognized.

      1 Ginther OJ. 1979. Reproductive Biology of the Mare: Basic and Applied Aspects. Ann Arbor, MI: McNaughton and Bunn, pp. 59–68.

      2 McCue PM, Scoggin CF, Lindholm ARG. 2011. Estrus. In: McKinnon AO, Squires EL, Vaala WE, Varner DD (eds). Equine Reproduction, 2nd edn. Ames, IA: Wiley Blackwell, pp. 1716–27.

       John J. Dascanio

       School of Veterinary Medicine, Texas Tech University, USA

      The mare’s perineum should be washed prior to internal reproductive procedures and in preparation for foaling, to remove gross debris and to reduce bacterial numbers. In addition, the perineum is washed prior to perineal surgery such as the placement of a Caslick suture (vulvoplasty). The perineum is also washed as part of the minimum contamination breeding technique to reduce contamination of the uterus during natural cover or artificial insemination.

      Equipment and Supplies

      Tail wrap, tail rope, non‐irritant soap, roll cotton, stainless steel bucket, plastic bag/bucket liner, paper towels, examination gloves.

       A tail wrap should be placed prior to washing of the perineum. This may be a reusable neoprene wrap, Velcro® wrap, gauze wrap, flexible elastic wrap (Vetrap™), or an obstetrical sleeve.

       A reusable neoprene Velcro® wrap is cost effective and quick in application. It should be washed regularly with a disinfectant soap and dried before reuse. This is especially important if the wrap is used with different mare populations. The prevention of disease transmission is difficult with the reuse of this wrap without sanitation; thus, if there is a suspicion of such, a disposable tail wrap should be used.

       A gauze wrap is placed on the tail using one of two techniques. With both techniques the wrap goes from the base of the tail to a level just below the ventral commissure of the vulva. Technique one is to start at the top of the tail and with every circumferential wrap, flip some tail hairs upward so that they become trapped between successive layers (Figure 3.1). This prevents the tail wrap from slipping down the tail. This tail wrap must be unwound to remove. The second type of gauze wrap starts at about the level of the ventral vulvar commissure (Figure 3.2). A small piece of gauze is left hanging and the wrap placed around the tail, moving upward to the tail base. Hair should not be included between layers, with each layer overlapping the previous slightly. Once at the tail base, the gauze is twisted 360 degrees so that the twisted part is on the dorsal tail, while the ventral aspect of the wrap remains flat and untwisted. This allows the twist to bite into the tail hair on the dorsum, preventing slippage of the wrap, while the flat underneath aspect prevents blood occlusion. The wrap is continued downward and is twisted upon every circumferential wrap ending at the point where the wrap began. The small hanging piece of gauze from the beginning is tied to the remaining wrap to prevent the wrap from coming loose. This wrap may be pulled from the top to slide down the tail and removed without having to unwind the wrap when the procedure is completed. This wrap acts like a Chinese finger trap.Figure 3.1 Gauze tail wrap with tail hairs flipped up to prevent sliding of the wrap down the tail.Figure 3.2 Gauze tail wrap twisted 360 degrees on the dorsum of the tail while the ventral aspect is wide.Figure 3.3 Elastic tail wrap encompassing the entire tail.

       If an obstetrical sleeve is used for a tail wrap, the tail is placed entirely inside the sleeve. The sleeve may be split at the tail base and tied together to close the sleeve around the tail base, or elastic adhesive tape or an elastic band and clamp may be used to wrap around the sleeve at the tail base to secure it. This type of tail wrap is useful for mares with diarrhea to prevent soiling of the tail hairs.

       If a flexible elastic wrap is used such as Vetrap™, the wrap may either be used to wrap the entire tail or the upper portion (Figure 3.3). The entire tail is wrapped for a dystocia or a fetotomy to prevent tail hairs from interfering with the procedure. To place the entire tail in a wrap, fold the tail hairs so that the hairs do not extend beyond the tail stump. Wrap the elastic wrap around the tail/tail hairs so that no hair is visible along the entire tail length. This in effect creates a “club” with the tail wrapped completely.

       After wrapping, the tail is held to the side so that the perineum can be washed or the tail is tied to the mare (Figure 3.4).

       Alternative tail wrap techniques include use of a sock held in place by 5 cm (2 inch) medical tape (Figure 3.5) or a plastic bag (75 × 25 cm (30 × 10 inches)) held in place by 2.5 cm (1 inch) rubber tubing and a clamp (Figure 3.6). The wrapped tail can be held out of the way by using an elastic cord (Figure 3.7) or being tied to the mare as previously described.