VIRGINIA COOPERATIVE EXTENSION SERVICE EXTENSION DIVISION - VIRGINIA POLYTECHNIC INSTITUTE AND ST ATE UNIVERSITY - BLACKSBURG, VIRGINIA 24061

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1 VIRGINIA COOPERATIVE EXTENSION SERVICE EXTENSION DIVISION - VIRGINIA POLYTECHNIC INSTITUTE AND ST ATE UNIVERSITY - BLACKSBURG, VIRGINIA VIRGINIA-MARYLAND REGIONAL COLLEGE OF VETERINARY MEDICINE VIRGINIA VETERINARY NOTES November 1980 No. 10 WHAT'S INSIDE Brucellosis Vaccination Information Meetings... Page 2 Time and location of meetings is given. Beef Breeding-Reproduction Symposium..... Page 2 Two symposiums will be held next month for producers, extension agents and veterinarians. Ram Epididymitis... Page 3 A vaccine is now available in Virginia. Evaluation of Procedures for the Diagnosis of Brucella ovis in Rams (Epididymitis)... Page 4 Six diagnostic procedures are compared. Gerbi 1 s Page 5 Facts about gerbil behavior, management, and health. Changes in Periparturient Fecal Egg Counts in Beef Cows Calving in the Spring Page 5 This experiment proved that worming beef cows at calving time is beneficial. d_ tl. f);a_c_~ G. A. Macinnis, D.V.M. Extension Specialist Virginia Cooperat111e Extension Ser111ce programs. act1111t1es. and employment opportunities are available to all people regardless of race. color. religion, sex. age, national origin. handicap, or poltt1cal aff11iat1on An equal opportunity/affirmat111e action employer. Issued in furtherance of Cooperat111e Extension work. Acts of May 8 and June 30, 1914, and September 30, 1977, 1n cooperation with the U. S. Department of Agriculture W. A. Van Dresser Dean Extension D1111s1on. Cooperat111e Extension Service. V1rgin1a Polytechnic Institute and State Un111ers1ty, Blacksburg. Virginia ; M. C. Harding, Sr.. Administrator Extension Program. Virginia State Un111ers1ty, Petersburg, Virginia 23803

2 -2- BRUCELLOSIS VACCINATION INFORMATION MEETINGS Virginia will switch to the reduced-dosage brucellosis vaccine in January, so it is important that all practicing veterinarians who plan on vaccinating calves for brucellosis attend one of the informational meetings that will be held at the Virginia Department of Agriculture Regional Laboratories. The dates and times of the meetings are as follows: Ivor - 7:45 p.m., November 24 Richmond - 1 :30 p.m., November 25 Lynchburg - 7:45 p.m., December 2 BEEF BREEDING-REPRODUCTION SYMPOSIUM Warrenton - 7:45 p.m., December 3 Harrisonburg - 7:45 p.m., December 8 Wytheville - 7:45 p.m., December 11 A one day Beef Breeding-Reproduction Symposium will be held on Monday, December 8,at the Red Carpet Inn on Interstate 64 west of Waynesboro. The symposium will be repeated on Thursday, December 11, at the Holiday Inn, Wytheville. The symposium is designed for purebred and commercial cattle breeders, extension agents, veterinarians, and other professional workers. The registration fee is $7.00 and includes coffee breaks, lunch, and proceedings. The program is as follows: BEEF BREEDING-REPRO SYMPOSIUM PROGRAM t-unday, DECEMBER 8, RED CARPET INN - WAYNESBORO IBURSDAY, DECF11BER 11, HOLIDAY INN - WYrnEVILLE 8:00-9 :30 a.m. - REGISTRATION - Registration fee -$7. 00 (includes lunch and proceedings). 9 :30-12:00 Noon - MORNING PROl.RAM - Steve Umberger, Moderator. 9:30 a.m. - (VELCOME - E. B. Morse & Benny Burkett, Host Extension Agents. 9: 35 a. m. - "MAKING BEST USE OF GENETIC SELECTION TOOLS (Pelt 0!t.m<t11c.e e,6,t..i11q, Sope.Jt.wlt S-ULe.6. va TMn,6 e'l - L. A. Swiqer, Head, An i ma I Science De rt : 15 a.m. - "MANAGEMENT FOR TOP PRODUCTION & REPROVUCTJON (Scl.ec.U.011, B11.e.e.clrn_9 I ca.lv.v1g Sc.he.du.le.&_, U!i..t ng Ava.<lable Va.ta)" - A. L. E 1 I er, Jr., VP I &SU 10 :45 a.m. - "Tiff ff.rtile BULL - HO(J) TO SELECT ANO MANAGE" - W. E. Beal, VPl&SU - 11:20 a.m. - "HCM TO USE YOUR VETERINARIAN (FeJttiUty and P1tegnanc.y Te.&t6, E~.tJtou:6'Sync.hJt.01i.tzilio11, HeJtd Heillh)" - T. L. Bibb, VP I &SU 12: 00 f'mn - LUNCH 1:00-4:00 p.m. - AFTERNOON PROGRAM - A. L. Eller, Jr., Moderator. 1:00 p.rn. -"PLANNED NUTRITION - Tiff KEY TO RfPROOUCTIVE SUCCESS" - H. J. Gerken, Jr. & W. 0. Lamm, VPl&SU 1:40 p.m. - "ESTROUS SYNCHl<ONIZATION ONE VEAR AFTER - How ha.6 it wo11.ke.d & What ;to exrec.;t" - Norman Vince I, Va.-N.C. Select Sires 2:20 p.m. - "PRACTICAL APPLICATION OF SYNCHRONIZED BREEDING - B'leedetr..6 Speak Ou,t" - Ernie Reeves, Mt. Solon & Roger Winn, Jr. Ax ton.. 3:00 p.m. - Coffee Break 3:15 p.m. - "OVA TRANSrER - A NEW DIMENSION" - J. A. Lineweaver & T. L. Bibb, VPl&SU 3: 50 p. m. - Q_UEST10NS & ANSWERS 4:10 p.m. - ~!WOSI~0 WRAP-UP - A. L. Eller, Jr., VPl&SU 4: 15 p.m. - ADJOURN.

3 -3- RAM EPIDIDYMITIS The incidence of ram epididymitis in Virginia flocks is high enough that the sheep breeders are concerned and will be seeking help in the control of this disease. The primary cause is Brucella ovis. The organism is discharged from an infected ram through the semen and the urine. The organisms gain entry into another ram by: 1) Breeding a ewe which has recently been bred by an infected ram. 2) Infected rams breeding other rams (sodomy). 3) Rams ingesting contaminated feed or water. The infection rarely causes a problem in the ewe. In the ram, the organism localizes in the epididymus causing tissue inflammation, swelling and scar formation. As the disease progresses, the functional testicular tissue shrinks and is replaced by scar tissue.. Reproductive failure occurs when the testicle is degenerate and/or when the epididymus becomes blocked from the inflamation and scarring. Epididymitis usually affects only one testicle and the ram is usually not totally infertile. However, testicular volume is directly correlated with fertility and the loss of one testicle reduces the breeding capacity of the affected ram. The results of a European study indicate 0-44 percent conception rates using rams that had both testicles affected and a 78 percent conception rate when only one testicle was affected. Healthy reproductively sound ewes should have conception rates of 95 percent and up. There is no known cure for the disease. It has been shown in California that a rigid culling and vaccination program can reduce the incident to less than one percent. There is an experimental vaccine made by the Colorado Serum Company that is effective in helping control this disease. Through the efforts of the Virginia Sheep Breeders, Dr. Jack Roth, State Veterinarian's Office, George Allen, Animal Science Department, Virginia Tech, and Dr. Tom Bibb, Virginia-Maryland Regional College of Veterinary Medicine permission has been granted for this vaccine to be shipped to and used in Virginia. The USDA has given Barber Veterinary Supply, Richmond permission to distribute the vaccine in Virginia and also have made Dr. Bibb responsible for compiling data on its use - doses used, effectiveness, etc. Veterinarians who purchase, use or dispense this vaccine will be contacted by Dr. Bibb for clinical information. Specific directions for its use come with the vaccine but the initial treatment calls for two vaccinations approximately 30 days

4 -4- apart some days ahead of the breeding season. Thereafter, an annual booster shot is required to maintain immunity. An annual vaccination program in conjunction with an annual rigid testicle palpation and culling program should reduce the evidence of epididymitis in rams. Thomas L. Bibb, D.V.M. Virginia-Maryland Regional College of Veterinary Medicine VPI & SU Blacksburg, Virginia EVALUATION OF PROCEDURES FOR THE DIAGNOSIS OF BRUCELLA OVIS INFECTION IN RAMS (EPIDIDYMITIS) Epididymitis caused by Brucella ovis is probably the most common cause of breeding impairment in rams rhe disease can be controlled, but to do so, it is necessary to identify and eliminate all infected rams. What diagnostic tests are available and which are the most reliable? Webb, et al, reported in the April 1980 Australian Veterinary Journal the results of their evaluation of 6 diagnostic procedures. Ten rams free of the disease were inoculated wi th a culture of Brucella ovis into the preputial cavity. Observations were undertaken at weekly intervals for one year to follow changes in clinical, bacteriological, and serological findings. l. Clinical examination - body temperature remained normal in all rams. Palpation of the epididymides revealed lesions (swellings) in 1 ram 3 weeks after innoculation and in all rams by 8 weeks; lesions had disappeared in 3 rams at the completion of the trial. 2. Detection of inflammatory cells in semen - the presence of inflammatory cells in semen samples was the earliest indication of infection being demonstrated in 2 rams at 2 weeks and in all rams by 6 weeks. In subsequent tests, 86% of samples were positive. At the final sampling all 10 rams were positive. Polymorphonuclear leucocytes were the main cells present throughout the trial. 3. Brucella ovis in semen smears - at 4 weeks Brucella ovis organisms were detected in semen smears of 3 rams and at 27 weeks in all 10 rams. Thereafter, the number of positive smears varied from 0-7 and, on only one examination (at 27 weeks) were all 10 rams positive. Overall, 52% of the semen smears from 4 weeks onward were regarded as positive. 4. Culture of Brucella ovis - Brucella ovis was cultured from semen of 5 rams after 4 weeks and from all rams at 5 weeks; thereafter, 97% of samples were positive.

5 -5- GERBILS 5. Complement Fixation Test - all rams developed significant titers to the CFT between 2 and 9 weeks; thereafter, the CFT was a reliable indication of infection in 6 rams, highly suggestive in 3, and unreliable in one. 6. Indirect Haemagglutination Assay - by 8 to 10 weeks all rams developed significant titers to the IHA which were then maintained in all rams for the remainder of the trial. Because of the relative simplicity and accuracy of the Indirect Haemagglutination Assay, the authors believe that this test should be further evaluated as a routine diagnostic test for Brucella ovis infection in rams. These desert rodents from Mongolia are clean and easy to handle. They tend to be monogamus and usually live two to four years. Hardier than hamsters, gerbils reach puberty at approximately 10 weeks of age, can be mated at 12 weeks, have an average gestation of 25 days, and produce litters of 4 or 5 young which are weaned at three weeks. Lab feed or rodent chow provide a balanced diet for these little animals. They drink relatively little water and have a concentrated urine. Coprophagy is considered normal behavior. Gerbils have few medical problems. The most common defect is a tendency to have spontaneous epileptiform seizures. Up to 20% of the population may be affected and a genetic basis is the probable cause. Injectable antibiotics, particularly pen-strep combinations, can be the cause of toxic reactions. Short course on Management of Small Mammals November 1980 Stuart L. Porter, V.M.D. Blue Ridge Community College CHANGES IN PERIPARTURIENT FECAL EGG COUNTS IN BEEF COWS CALVING IN THE SPRING A herd of mature Angus and Angus-Holstein-Friesian cows calving between March and May was maintained at 80% and 100% of National Research Council's recommended total digestible nutrient (TON) levels during the winter. Changes in fecal nematode egg counts of these cows, expressed as eggs/5 g of feces and quantitated by the Wisconsin sugar flotation technique, were detected perinatally and were correlated with breed, nutritional level, and time of year. A limited, yet highly significant increase in egg output was found in cows at calving. Anthelmintic treatment at calving caused postcalving egg counts that were statistically lower than were those from nontreated cows. When breed and nutritional level were considered independently, there was less influence on egg counts than when the interaction of breed and nutritional level was examined.

6 -6- Angus-Holstein-Friesian cows fed 80% TON requirements had the greatest perinatal increase in egg output, and those fed 100% TON had the smallest increase of all groups. Angus cows responded in an opposite manner to the nutritional level and had increases in egg counts intermediate to those counts of Angus-Holstein-Friesian cows. This characterization of the periparturient egg output by mature cows aided in evaluating the role of grazing cows in contaminating pastures. Bruce Hammerberg, DVM, PhD Virginia-Maryland Regional College of Veterinary Medicine, VPI & SU W. Dennis Lamm, PhD Department of Animal Science VPI & SU American Journal of Veterinary Research Vo 1. 41, No. 10 COOPERATIVE EXTENSION SERVICE U. S. DEPARTMENT OF AGRICULTURE VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY BLACKSBURG, VIRGINIA OFFICIAL BUSINESS PENAL TY FOR PRIVATE USE, S300 POSTAGE AND FEES PAID U. S. DEPARTMENT OF AGRICULTURE AGR-tOt Third Class Bulk Rate ri