Turnover of Dominant Follicles prior to First Ovulation and Subsequent Fertility in Postpartum Dairy Cows

Contents: The ovaries of 64 multiparous Holstein cows were scanned twice weekly by ultrasonographyfrom Day 6 postpartum until 60 days or return to normal estrous cycle, and turnover of dominant follicles in relation to subsequent fertility were determined. The mean (SD) number of days from parturition to detection of the first postpartum dominant follicle (10 mm) was 9.0 0.5, which was predominantly located in the ovary contralateral to previous pregnancy in 54/64 cows. The first postpartum dominant follicle ovulated in 34 cows, failed to ovulate in 18, became cystic in 10, and only 2 were diagnosed as ovarian quiescent which delayed the detection of dominant follicles until days 25 and 30 postpartum. Number of dominant follicles in cows with anovulated first dominant follicle was 2.8. 1.1 prior to first ovulation (range 2–5). Growth and regression of cystic follicles were observed 24 times in 6110 cows, and a total of 20 cystic follicles persisted 32.7 9.0 days (range 18–58 days) except one which persisted for 124 days. Conception rate was 89.5% and postpartum interval to conception within 180 d after calving was 96.7 days in cows detected with less than 3 dominant follicles before first ovulation compared with those of 42.9% and 141 days in cows detected with more than 4 dominant follicles. It is concluded that the number of dominant follicles detected prior to first ovulation varied from I to 5, which positively correlated with ovulation intervals, while only those cows which first ovulated less than 3 dominant follicles resulted in reasonable reproductive performance.     

Survey of infectious coryza of chickens in Indonesia.

A survey of infectious coryza of chickens was performed in West Jawa of Indonesia between 1987 to 1988 by the detection of hemagglutination-inhibition (HI) antibody against Haemophilus paragallinarum (Hpg) in non-vaccinated healthy laying (12 farms, 196 chickens) and native (8 farms, 197 chickens) chickens. HI antibodies against Hpg were detected not only in the native chickens but also in the laying chickens, regardless of the district, and were observed in 70% (14/20) of farms and 19% (73/393) of chickens. HI antibodies against serotype A were detected from 11 farms (55%) and 11% (45/393) in chickens. Those against serotype C were detected from 5 farms (25%) and 8% (30/393) in chickens. Three Hpg strains were isolated from different chickens affected with infectious coryza. Two of them were identified as type A and the other as type C by the rapid plate agglutination test. These results demonstrated that the outbreaks of infectious coryza caused by serotype A and C strains had occurred in Indonesia.     

A survey of antibodies to arthropod-borne viruses in Japanese cattle

Sera collected from the southern parts of Japan were subjected to serological tests for antibodies to 24 arthropod-borne or suspected arthropod-borne viruses. A high incidence (82%) of hemagglutination-inhibiting (HI) antibodies was found with Japanese encephalitis (JE) virus. HI antibodies to other Flaviviruses, Murray Valley encephalitis, Apoi, Kunjin, Stratford and Kokobera, were also found in some of the sera, but seemed to be due to cross reaction with JE virus. High neutralizing (NT) antibody incidences were obtained with Akabane (60%) and Aino (30%) viruses known to be endemic in Japan. NT antibodies were also found for Bunyaviruses, Batai and Wongla; Reoviridae viruses, D'Aguilar, Warrego, and Mitchell River; and Kowanyama and Belmont viruses. Complement fixing antibodies were found for Reoviridae viruses bluetongue type 1 and Ibaraki; Picornavirus Nodamura and Rhabdovirus bovine ephemeral fever. No antibodies were detected with Reoviridae viruses Corriparta and Eubenangee; Bunyavirus Trubanaman; and Alfavirus Chikungunya.     

Epizootic diarrhoea of adult cattle associated with a coronavirus-like agent

An epizootic of acute diarrhoea of adult cattle occured in Japan during the winter of 1976 to 1977. A majority of adult cattle clinically diagnosed as having the disease, showed a significant rises in antibody titres to bovine coronavirus, whereas only a smal; minority showed serological evidence of recent infection with calf rotavirus, bovine adenovirus type 7, parainfluenza virus type 3, or bovine viral diarrhoea-mucosal disease virus. A coronavirus-like agent was detected by electron-microscopy in faecal material from a cow with diarrhoea, and was subsequently isolated in primary bovine kidney cell cultures.     

Bar-structure in bovine erythrocytes infected with Theileria sergenti

The purpose of this study is to elucidate some morphological characteristics of the bar-structure in bovine erythrocytes infected with Theileria sergenti. The bar-structure, the veil or the both were observed in infected erythrocytes. Infected bovine erythrocytes were classified into four types according to the included structures. Infected cells containing bar-structures increased with the progress of parasitemia. In Giemsa-stained blood preparations, bar-structures appeared purplish-red and measured a mean of 1.6 micron in length and up to 0.1 micron in width. Bar-structures were usually straight, sometimes S-shaped, and located in the periphery of infected erythrocytes. In the direct fluorescent antibody test with T. sergenti-positive bovine serum both piroplasms and bar-structures exhibited fluorescence. However, in the indirect fluorescent antibody test with monoclonal antibodies against piroplasms only piroplasms showed a highly specific fluorescence. Electron microscopy revealed that bar-structures were vesicular in structure, surrounded by a double membrane connected to the host cell membrane.