Field outbreaks of hyperoestrogenism (vulvo-vaginitis) in pigs consuming maize infected by Fusarium graminearum and contaminated with zearalenone

During the spring and summer of 1979 field outbreaks of porcine hyperoestrogenism characterized by swelling and reddening of the vulva and teats in prepubertal gilts and enlargement of the mammae in young males occurred in the mistbelt of the Natal Midlands. On a farm in the Ixopo district, pigs were fed a mixed ratio containing home-grown yellow maize stored on the cob in a crib and all the young pigs with a mass of 25-85 kg (=a total of 350) were affected. Maize ears from the crib had a high percentage (91%) of kernels infected by Fusarium graminearum and contained 10 mg/kg of zearalenone. The mixed ration contained 0,95 mg/kg zearalenone. After dilution of the contaminated maize with good quality white maize, a dramatic decrease in both the incidence and severity of clinical signs occurred within 3-4 days. On a farm in the Winterton district, approximately 80% of the growing pigs with a mass of more than 40 kg fed a mixed ration containing shelled yellow maize from the silo of the local Agricultural Co-operative were affected. The incidence as well as the severity of the swelling of the vulvas and/or treats were lower than on the farm at Ixopo, thus indicating a lower level of oestrogen intake. A sample of maize from the silo delivered to this farm contained only 0,06 mg/kg zearalenone while the mixed ration did not contain chemically detectable levels of zearalenone. This is the first published record of field outbreaks of porcine hyperoestrogenism associated with the ingestion of F. graminearum infected maize contaminated with zearalenone in the Republic of South Africa.

[Allergic skin reaction in infectious rhinotracheitis and infectious pustular vulvovaginitis in cattle]

Through a skin-allergic reaction were subjected to a study cattle of different ages (calves-sucklings, growing calves and grown up calves), originating from 4 different from the epizootic point of view cow-farms--one latent focus, two foci with an apparent infection and one cow-farm in good health conditions. On the healthy cow-farm the skin-allergic reaction and the virus neutralizing reaction were not marked. On the farms affected with latent infection and with manifestation of abortions with cows, the skin-allergic reaction with calves till the age of 3 months was negative, whereas the virus neutralizing reaction was usually positive; with the calves at the age of about 6 months the skin-allergic reaction began slightly to become positive. The virus neutralizing reaction was also positive. With the grown up animals both reactions were positive. In the development of recently brought clinical infection among the calves, without affecting their mothers, both reactions were negative with newly born calves, whereas from the second month onward, they began to become positive.

Evaluation of the rabbit as a laboratory model for infectious bovine rhinotracheitis virus infection

Experimental infection of rabbits with infectious bovine rhinotracheitis virus (IBRV) produced diverse manifestations of disease which included abortion, conjunctivitis, dermatitis, vulvovaginitis, systemic infection, neonatal death and respiratory tract infection. Each disease syndrome was studied using virus isolation, fluorescent antibody examination and histologic examination. Conjunctivitis, dermatitis and vulvovaginitis lesions were characterized by edema, infiltration of mucosa and submucosa with inflammatory cells and ulceration of epithelium. Systemic infection resulted in severe necrosis of liver and adrenal glands with large numbers of cells containing intranuclear inculsions. Pregnant rabbits aborted within 48 hours following inoculation of IBRV. Virus infection and viral lesions were not demonstrated in aborted fetuses.

Infectious bovine rhinotracheitis: a review and update

Infectious bovine rhinotracheitis (IBR), a herpesvirus infection of cattle, has diverse clinical manifestations. Known mainly as a respiratory tract disease characterized by tracheitis, rhinitis, and fever, IBR plays a prominent role among causes of undifferentiated bovine respiratory disease and abortion. It also causes conjunctivitis, infectious pustular vulvovaginitis, balanoposthitis, and rarely, encephalitis. The virus is readily transmitted and has worldwide distribution. Some cattle develop a latent infection, which can be reactivated. The disease can be diagnosed by clinical signs and lesions and by a variety of virologic and immunologic techniques. Control of IBR is based largely on vaccination. A review is timely because efficient utilization of the wide assortment of available vaccines requires knowledge of recent developments in the diagnosis, immunology, and epidemiology of the disease.

Isolation of mycoplasmas from the genital tract of horses

Vaginal swabs from 19 mares and penile swabs from 4 stallions were cultured for mycoplasmas. A single semen sample from one of the stallions was also examined. Twelve vaginal swabs and 2 penile swabs yielded mycoplasmas. Ten of the positive vaginal swabs were from mares with vaginitis, or with a history of failure of conception. Two were from apparently healthy mares, but one had been served by an infected stallion. One positive penile swab was from a stallion with ulcerative lesions and the other from a stallion with breeding difficulties. All 14 strains of mycoplasma utilised arginine, and the growth of 11 strains was inhibited by hyperimmune serum against one strain.

Studies on the effects of infectious bovine rhinotracheitis virus on reproduction in heifers

Natural venereal infection of heifers with IBR virus resulted in vulvovaginal lesions in 9 of 12 heifers at 3 weeks after introducttion to bulls, and virus was isolated from 5 of the 9 affected animals. The infection was not associated with any effect on conception. Experimental nasal and conjunctival infection of 18 heifers pregnant for 3, 5 or 7 months with a genital strain of IBR virus caused mild rhinitis or conjunctivitis in all inoculated animals and virus was recovered from 14 animals at 8 days after inoculation. No effects on pregnancy were recorded.

The effect of natural and artificial breeding using bulls infected with, or semen contaminated with, infectious bovine rhinotracheitis virus

Ten cows and heifers (Group B) were inoculated into the uterus at oestrus with semen followed by IBR virus for the first insemination and semen alone if a second insemination was necessary. All animals developed infectious pustular vulvo-vaginitis (IPV), and 2 cows conceived to the first and 2 to the second insemination (pregnancy rate of 40 percent requiring 4.5 services per conception). This group was compared with 10 control animals (Group A) which were treated similarly but received tissue culture fluid instead of virus at the first insemination. Group A had a pregnancy rate of 90 percent requiring 1.7 services per conception. Natural mating of 4 bulls with preputial infections due to infectious bovine rhinotracheitis (IBR) virus with 9 susceptible cows and heifers (group D), resulted in the production of lesions of IPV. The IPV infection did not affect their fertility (pregnancy rate of 89 percent requiring 1.4 services per conception) when it was compared to a similar group of females (group C) mated to the same bulls prior to infection with IBR virus (pregnancy rate of 100 percent requiring 1.2 services per conception). The 6 animals in Group B that were not pregnant and returned to oestrus 3 times were found on slaughter to have endometritis, salpingitis and vaginitis. A high incidence, 5 out of 18 (28 percent), of shortened oestrous cycles (less than 18 days) was a feature of the breeding pattern of this group. The undesirable consequences of distributing semen contaminated with IBR virus from artificial insemination centres are apparent.

Pathology of Mycoplasma agalactiae induced granular vulvovaginitis (GVV) in goats

Granular vulvovaginitis (GVV) was experimentally produced in female kids by topical application of M. agalactiae on the scarified vulvar mucosa. Grossly visible GVV lesions were seen in 25 out of 30 infected kids, yet all were positive for microscopic lesions. Microscope lesions that appeared by 7 days post infection (DPI) were comprised of stromal oedema, lymphocytic infiltration into the lamina propria and perivascular accumulation of a few lymphocytes. The lesions observed between 28 and 49 DPI were comparable to those of spontaneous cases (severe). The changes seen in kids euthanized between 56 to 70 DPI were suggestive of the chronic stage of the disease. M. agalactiae was reisolated from all the infected kids from 7 to 70 days after inoculation. The pathology and pathogenesis of this condition have been described and discussed.

Infectious bovine rhinotracheitis-infectious pustular vulvovaginitis viral isolates from cattle with epididymitis and vaginitis

Infectious bovine rhinotracheitis-infectious pustular vulvovaginitis (IBR-IPV) viral isolates were obtained from cattle affected with epididymitis-vaginitis. Isolation of virus from the diseased animals indicated that the genital form of IBR-IPV virus infection exists in Kenya and that epididymitis-vaginitis may be associated with IBR-IPV virus. Serums prepared from cattle having the genital form of the disease did not always have detectable antibody titers.