Entering the Rectum
1) The cow is restrained by placing it in a chute or stanchion.
2) The cow is approached in a way that minimizes fright to the animal. Do not make sudden movements or act in a loud, frightening way, especially if the cow is not habituated to people. Dairy cows will usually not kick although some will. One can approach the cow slightly from the side to avoid kicks. The cow can be gently touched on the flank or back to make it aware of the palpator’s presence and to allow evaluation of the cow’s temperament.
3) Before beginning palpating, the arm used for palpation (either will do; whatever is most comfortable) should be covered with a palpation sleeve. A variety of sleeves are available. One workable alternative is to use an inexpensive, disposable palpation sleeve with a tighter-fitting latex glove fitted over the hand. The palpation sleeve can be attached to the sleeve of the coveralls or work shirt with a hemostat or clothespin.
4) After donning the palpation sleeve, the glove should be lubricated with K-Y jelly or a commercially-available lubricant such as those sold by Nasco or ABS.
5) Approaching the cow while standing somewhat sideways, grab the tail with the ungloved hand and push it aside (for cows prone to kicking, the tail can be raised perpendicular to the cow to prevent kicking). The anus can be identified as the upper of the two openings under the tail (the lower one being the vulva). If there is only one opening present, look around to see which of your co-workers has slipped a bull or steer into the string of animals being palpated.
6) To enter the rectum, form the hand into a cone shape by bringing the fingers and thumb together and use a slight rotary motion to insert the fingers and hand into the rectum. Entering the rectum takes some physical effort because of the strength of the anal sphincter muscle and because of peristaltic contractions in the rectum. The contractions often subside after the arm has been placed in the rectum. If the contractions are especially large (the cow has arched her back to generate additional contractile force), one can have a coworker press down on the animal’s spine to lower the pressure. To enter the rectum while strong contractions are taking place, the palpator must use enough force to overcome the contractions while being careful to avoid injuring the cow.
7) After the rectum has been entered, the palpator should remove fecal material from the rectum by using the cupped hand as a rake. Removal of fecal matter is not always necessary if the feces are not abundant or are very soft.
8) It is possible for the cow to suck air into the rectum, especially if the palpator makes many rapid in-an -out motions with the arm. When this occurs, it is nearly impossible to palpate the reproductive tract because the rectum balloons outwards. To reduce the problem, air can sometimes be removed by grasping a fold of the rectal wall and slowly moving it backwards to the anus.
Finding and Palpating Structures in the Reproductive Tract
1) For a new palpator, the cervix is usually the best landmark to help find the reproductive tract. The cervix can be identified as a rope-like or chicken-neck-like structure about 3 inches in diameter that is usually in the pelvic cavity along the midline. Sometimes, the bladder can displace the reproductive tract so that it lies to the right side of the pelvic cavity.
2) The cervix can be picked up and held in the hand. Do not attempt to grab the cervix between thumb and the first two fingers of the hand because it is hard to hold the cervix in this manner. Rather, grab the cervix from the side while placing the the fingers underneath the cervix and the thumb on top. If the reproductive tract is located far forward in the abdominal cavity, one can use the cervix to pull the reproductive tract into the pelvic cavity.
3) The uterus can be identified and examined by following the cervix forward. To do so, the cervix and uterus is grasped in the hand so that the hand lies over the tract with the palm down and the thumb underneath the tract. The external bifurcation can be identified as the point where the two uterine horns branch from the uterine body. The two horns should be roughly the same size although this will not be the case during late pregnancy and the early postpartum period. The uterine horns can very greatly in size depending upon the reproductive status of the animal. At estrus, the horns tend to be in a turgid, muscular state. Acyclic and sterile animals will often have a very small or nearly- infantile reproductive tract. After calving, the uterine horns will be very large, with one uterine horn larger than the other and with the reproductive tract displaced into the abdominal cavity.
4) The ovaries are either tucked slightly underneath the uterus or located to the side of the uterus at a variable distance. Sometimes, the ovaries can be found by grasping the uterus, and then, after release of the uterus, turning the hands counterclockwise while using the fingers to probe for the ovary.
4) Once located, the ovary can be grasped with the fingers while the ovary is held in the palm. The fingers can be moved along the entire surface of the ovary – periodic pressure is applied by the fingertips to search for ovarian structures. Follicles appear as pliable, fluid-filled structures. Care must be taken to avoid rupturing preovulatory follicles. Corpora lutea appear as hard structures that often protrude from the edge of the ovary. Sometimes, the ovulation fossa can be identified as a protruberance from the surface of the corpus luteum.
5) The oviducts are usually not found during palpation unless some pathology is present (i.e., oviductal inclusion or infection).