Hemoglobin Binding Assay (HBA), one of the methods of bovine serum haptoglobin (Hp) analysis, was modified to shorten the reaction time. The values of bovine serum Hp determined by modified HBA highly correlated with those determined by single radial immunodiffusion assay, and the assay reproducibility (intra- and inter-assay) was acceptable. In healthy postpartum cows, the concentration of serum Hp was elevated until 3 days after parturition and subsequently decreased. The values of the mean, median, and 95th percentile in healthy cows (6-16 weeks after parturition, n = 754) were 110, 98, and 170 μg/ml, respectively. The median value in healthy heifers (n = 41) was 88 μg/ml (mean 91 μg/ml). The levels of serum Hp in cows suffering from post parturient mastitis and a retained placenta were significantly higher than those in healthy cows (1 and 3 days after parturition). Serum Hp was significantly high in cows with acute mastitis or clinical mastitis, compared to those in healthy cows. These results suggest that the modified HBA could be a useful method for diagnosis in postpartum cows.
In this study, we assessed six cases of extraintestinal pathogenic Escherichia coli (ExPEC) infection in Japanese black calves and used PCR analysis to detect the virulence-associated genes of the ExPEC isolates obtained from the internal organs of each calf. The clinical signs in the calves included ananastasia, opacity eyes, and respiratory disorder. Histological analysis confirmed the presence of bronchopneumonia, multifocal necrosis,and centrilobular necrosis in the liver, purulent meningitis, and disseminated intravascular coagulation. The virulence-associated genes of the ExPEC isolates encoded toxins (cnf2 and cdt III ), adhesins (F17A and afa8), and siderophores (iutA, fyuA, irp1, and irp2). These results indicated that the virulence-associated genes of these E. coli strains may cause ExPEC infection in calves.
We examined the antibody response of young Holstein breeding calves to Mannheimia haemolytica (Mh) vaccine containing inactivated capsular antigen and leukotoxin (LKT). Twenty calves that had been raised on a dairy farm in the Nemuro District of Hokkaido, Japan, and that had received adequate colostrum, were allocated to four groups that were vaccinated under different schedules. Group A (5 calves) received no injection of Mh vaccine; Group B (5) received a single injection at age 1 month; Group C (5) received a single injection at 5 months; and Group D (5) received two injections, the first at 1 month and the second at 5 months. After weaning, antibody titers against whole cell antigen in Group B were significantly higher than those in Groups A and C. There was no significant difference between Group B and D. These results suggest that a single,early vaccination could ameliorate Mh-associated respiratory disease in calves at weaning and during transportation.
An 8-year-old Fisher’s love bird with skull mass died, considered to be the result of emaciation stemming from feeding difficulties and respiratory failure. At necropsy, the periosteal abnormal proliferative bone was additionally located on the external and internal surfaces of the cranial and mandibular cortical bone. Vascular lesions indicated as atherosclerosis were found in the bone mass and multiple internal organs.