Bovine Reproduction. Группа авторов
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Marden, W. (1954). New advances in the electroejaculation of the bull. J. Dairy Sci. 37: 556–561.
9 9 Ball, L. (1973). Electroejaculation of the bull. Bovine Pract. 7: 46–48.
10 10 Barker, C. (1958). The collection of semen from bulls, rams and bucks by electro‐ejaculator. Can. J. Comp. Med. 22: 3–8.
11 11 Nilsson, L. and Tanis, J. (1959). Report on finger‐electrode electroejaculator. J. Am. Vet. Med. Assoc. 134: 25–26.
12 12 Palmer, C. (2005). Welfare aspects of theriogenology: investigating alternatives to electroejaculation of bulls. Theriogenology 64: 469–479.
13 13 Etson, C., Waldner, C., and Barth, A. (2004). Evaluation of a segmented rectal probe and caudal epidural anesthesia for electroejaculation of bulls. Can. Vet. J. 45: 235–240.
14 14 Furman, J., Ball, L., and Seidel, G. (1975). Electroejaculation of bulls using pulse waves of variable frequency. J. Anim. Sci. 40: 665–670.
15 15 Salisbury, G., VanDemark, N., and Lodge, J. (1978). Physiology of Reproduction and Artificial Insemination of Cattle. New York: WH Freeman and Company.
16 16 Barth, A. (2007). Evaluation of potential breeding soundness of the bull. In: Current Therapy in Large Animal Theriogenology, 2e (eds. R.S. Younquist and W.R. Threlfall), 228–240. Philadelphia: WB Saunders Company.
17 17 Hopper, R. and King, E. (2015). Evaluation of breeding soundness: basic examination of the semen. In: Bovine Reproduction (ed. R.M. Hopper), 68–78. Chichester: Wiley.
18 18 Hill, H., Frank, F., Homan, N., and Gassner, F. (1956). Electroejaculation in the bull. J. Am. Vet. Med. Assoc. 128: 375–380.
19 19 Falk, A., Waldner, L., Cotter, B. et al. (2001). Effects of epidural lidocaine anesthesia on bulls during electroejaculation. Can. Vet. J. 42: 116–120.
20 20 Barth, A. (1997). Evaluation of potential breeding soundness of the bull. In: Current Therapy in Large Animal Theriogenology (ed. R.S. Youngquist), 222–236. Philadelphia: WB Saunders Company.
21 21 Blockey, M. (1976). Sexual behavior of bulls at pasture: a review. Theriogenology 6: 387–392.
22 22 Boyd, G., Healy, V., Mortimer, R., and Piotrowski, J. (1991). Serving capacity tests are unable to predict the fertility of yearling bulls. Theriogenology 36: 1015–1026.
23 23 Barth, A., Arteaga, A., Brito, L., and Palmer, C. (2004). Use of internal artificial vaginas for breeding soundness evaluation in range bulls: an alternative for electroejaculation allowing observation of sex drive and mating ability. Anim. Reprod. Sci. 84: 315–325.
24 24 Palmer, C., Amundson, S., Brito, L. et al. (2004). Use of oxytocin and cloprostenol to facilitate semen collection by electroejaculation or transrectal massage in bulls. Anim. Reprod. Sci. 80: 213–223.
25 25 Palmer, C., Brito, L., Arteaga, A. et al. (2005). Comparison of electroejaculation and transrectal massage for semen collection in range and yearling feedlot beef bulls. Anim. Reprod. Sci. 87: 25–31.
26 26 Roberts, S. (1986). Veterinary Obstetrics and Genital Diseases (Theriogenology), 3e. Woodstock, VT: Author.
27 27 Barth, A. and Oko, R. (1989). Abnormal Morphology of Bovine Spermatozoa. Ames, IA: Iowa State University Press.
28 28 Anderson, J. (1939). Investigations on the semen of fertile and sterile bulls. Vet. J. 95: 457–473.
29 29 Blom, E. (1973). The ultrastructure of some characteristic sperm defects and a proposal for a new classification of the bull spermiogram. Nord. Vet. Med. 25: 383–391.
30 30 Blom E. Sperm morphology with reference to bull infertility. Proceedings of 1st All India Symposium on Animal Reproduction, Ludhiana, 1977, pp. 61–81.
31 31 Saacke, R., Dalton, J., Nadir, R. et al. (2000). Relationship of seminal traits and insemination time to fertilization rate and embryo quality. Anim. Reprod. Sci. 60–61: 663–677.
32 32 Saacke, R. (2008). Sperm morphology: its relevance to compensable and uncompensable traits in semen. Theriogenology 70: 473–478.
33 33 Barth, A. and Bowman, P. (1994). The sequential appearance of sperm abnormalities after scrotal insulation or dexamethasone treatment in bulls. Can. Vet. J. 34: 93–102.
34 34 Meyer, R. and Barth, A. (2001). Effect of acrosomal defects on fertility of bulls used in artificial insemination and natural breeding. Can. Vet. J. 42: 627–634.
10 Ultrasound Examination of the Reproductive Tract
Harry Momont1, Mary Keeler2, and Michael Nicholson2
1 Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin‐Madison, Madison, WI, USA
2 ABS Global, DeForest, WI, USA
Introduction
Diagnostic ultrasound has become the standard for medical imaging of soft tissue. The genital tract is an obvious target for this diagnostic modality and while ultrasound is routinely employed for evaluation of the female genital system its use in male domestic animals remains much less common. In the bull, for example, the routine bull breeding soundness examination (BBSE) as recommended by the Society for Theriogenology does not require ultrasonographic assessment of the genital system [1, 2]. In many cases of infertility in the bull, adequate diagnostic and prognostic information is obtained without the use of ultrasonography. A major advantage of ultrasonography is the ability to localize and objectively assess morphologic changes in tissue.
A thorough history, complete physical examination, and a BBSE should accompany an ultrasound examination of the bull's genital system. We routinely perform ultrasound evaluations for bulls with palpable or visible abnormalities of the genital system; those with pyospermia, hemospermia, azoospermia, or oligospermia; those with low semen volume; and bulls that persistently produce high numbers of morphologically abnormal or immotile sperm. As with any medical technology, the use of ultrasonography for examination of the bull will expand as veterinarians become more familiar with the modality and its applications.
Equipment and General Methodology
A wide variety of ultrasound equipment is available for diagnostic imaging. Most veterinary clinics providing service to cattle owners will already have a portable, real‐time, B‐mode system with a linear intrarectal probe that is used for reproductive examination of cows. All illustrations in this chapter were obtained with this type of system. Typical probe frequencies range from 5 to 7.5 MHz and are more than adequate for imaging the bull's reproductive tract. More detailed images of the epididymis and penile tissues can be obtained using probes with a smaller footprint and higher frequency. Representative images may be captured, labeled, measured, and saved for inclusion in the medical record. These applications are available with most ultrasound systems.
In order to adequately assess a machine that you intend to purchase, it is advisable to use it in an actual clinical setting so you can critically evaluate functionality and image quality under real‐world conditions. Beyond the primary issue of image quality, durability and resistance to damage from dirt and moisture are important considerations when purchasing an ultrasound unit to be used in cattle environments.
Operator safety is always a concern when working with bulls. A chute or stock with a head catch and squeeze option is ideal. For added security, the bull's head can be secured with a halter. Most bulls will tolerate scrotal, perineal, and rectal examinations with little restraint beyond confinement in the chute. If a kick bar is used behind the bull, extreme caution is needed to avoid placing the arms and hands in a dangerous position. For fractious bulls or for examination of the prepuce and penis cranial to the scrotum, we prefer sedation (xylazine 0.01–0.02 mg/kg IV).
While it is beyond the scope of this chapter, a fundamental understanding of ultrasound