Bovine Reproduction. Группа авторов
Читать онлайн книгу.the bull enters the chute, the examination should begin with the head. The areas on and around the eyes should be examined for squamous cell carcinomas, corneal damage, and lymphomas. The nasal passages are checked for even and equal air flow, the oral cavity is examined for abnormalities, and the age of the bull is confirmed by checking the dentition (Figure 8.2). This is also a good vantage from which to observe the front feet for interdigital fibromas and the screw claw abnormality.
Figure 8.2 Examination of the oral cavity and dentition to assess aging.
Examination of the Reproductive System
Scrotum and Testicles
The scrotum, testes, and spermatic cord should be examined carefully for fluid, fibrotic tissue, size, symmetry, shape, and texture. The scrotum should be examined for scars and its ability to extend or stretch to allow the testicles to cool. The testes should be palpated and have the texture of meat and be freely moveable within the scrotum. Any fibrotic or swollen areas should be noted. The epididymides should be palpated from the head dorsally, down the body, ventrally to the tail, for abnormalities such as epididymitis or fibrosis. The spermatic cord is palpated from the external inguinal ring distal to the testicle for abnormalities such as hernias, hematomas, fibrosis, or fluid. The external prepuce should be observed and palpated for abscesses and swellings, as well as hematoma of the penis directly anterior to the scrotum. Problems identified during scrotal examination can include scrotal skin lesions such as frostbite, dermatitis, scrotal edema, and blood warts. There are several normal variations of scrotal shape and testicular positioning within the scrotum. Thus, the presence of hydroceles and hematoceles as well as inguinal hernias must be ruled out in bulls with aberrances in scrotal size and shape [2, 5].
Ancillary testing utilizing ultrasound or thermography, although usually not necessary to classify a bull by the SFT standards, can be useful to further investigate abnormalities discovered during the physical examination [2].
Internal Reproductive Genitalia
A transrectal examination is utilized to evaluate the internal reproductive genitalia and can be aided or enhanced with the use of ultrasound. Each of the secondary sex organs should be carefully identified and palpated for any changes from the norm. The urethralis muscle is the first to be encountered and should be palpated for abscesses and tumors. As you palpate forward, the prostate and seminal vesicles (vesicular glands) are encountered. Palpation of both vesicular glands should begin at the bifurcation with the vesicle surrounded by the hand as it is palpated toward and to each distal endpoint. Texture, size, the presence of heat or pain, and distinction of the lobulations should be noted. Vesicular adenitis is one of the most common abnormalities suggested by the internal reproductive examination. Evidence of previous infection or injuries to the seminal vesicles can also be diagnosed by the presence of fibrosis and adhesions. Approaches to the diagnosis and treatment of vesicular adenitis are discussed in Chapter 14. The paired ampullae should be examined next for abnormalities as well as gently massaged to aid in semen collection. The examiner should use the transrectal examination as an opportunity to palpate the internal inguinal rings for size and the presence of hernias. The caudal abdomen should also be palpated for the presence of enlarged lymph nodes that could be suggestive of infection or neoplasia [5].
Penis and Internal Prepuce
The penis has already been palpated during the examination of the external prepuce but must be carefully examined and palpated while extended during the collection stage of the BBSE. Problems such as warts, hair rings, lacerations, and persistent frenulum will be discovered at this point. The internal prepuce presents itself for thorough examination during erection, allowing the opportunity to observe lacerations, warts, and fibrotic areas from old injuries that may cause deviations of the penis preventing coitus. The necessity of completely extending the penis at some point of the examination cannot be overemphasized as the previously mentioned conditions will be missed if this is not done. In‐depth coverage of urogenital injuries and their diagnosis, management, and correction are covered in Chapters 15, 18, and 19.
Example of an Examination Protocol
The examination begins with a history and examination at a distance. Evaluate conformation and be certain to record observations and identification of those bulls that have issues. Watching each bull approach the chute is a good time to observe the gait of the bull and overall appearance. Once in the chute, the bull's identification (tag, tattoo, or brand ID), eyes, head, and front claws are observed and observations recorded [6]. From the side of the bull, the testicles are palpated and SC measured (Figure 8.3), the prepuce is palpated for abnormalities, and the hind feet are observed. At this point the scrotal measurement and any observations are recorded. The rear of the bull is then approached and the back, hind legs, and especially the hock joints are observed and/or palpated. Transrectal palpation is then performed, again using a constant sequence. In the pelvic area, the urethralis muscle is followed forward to the seminal vesicles, which are palpated and massaged, the fornix of the seminal vesicles is located, and the ampullae are palpated and massaged, as are the inguinal rings, pelvic lymph nodes, the kidney, and any viscera within reach. The ampullae and the seminal vesicles are then massaged again. The urethralis muscle and the prostate are identified and massaged while progressing toward the anus. In addition to identifying abnormalities or eliciting a painful response, which may indicate a problem, palpation and massage serves to stimulate the bull and facilitate ejaculation (Figure 8.4). Thereafter, the electroejaculator is placed on the standard program and the probe is inserted into the rectum. At this point any observation or abnormalities from palpation are recorded. As erection and protrusion occur, the internal prepuce and the penis are examined by observation and palpation for abnormalities. After microscopic examination of the semen has been done, the bull is then released from the chute. The bull is observed leaving the chute and the chute area for lameness. It is of utmost importance that a standard protocol be developed to ensure that all areas of the physical examination and SC are checked and recorded [2, 5].
Figure 8.3 The correct way to measure SC. The testes are pushed toward the bottom of the scrotum and the scrotal tape is placed at the widest area. The scrotal tape should be pulled tightly.
Figure 8.4 Transrectal palpation to evaluate the internal reproductive tract and prepare the bull for electroejaculation.
Scrotal Circumference
The SC measurement is obtained while doing the general and reproductive examination [6]. It can be obtained from the side or the rear, depending on preference, facilities, and the bull's temperament.