Ketosis occurred to 740 dairy cows in Ishioka, Ibaraki Prefecture, and its vicinity over an eightyear period of 1960 to 1967. A survey was conducted on these cows with the following results.
1. Of the types of ketosis, the digestive type was the most prevalent, affecting 75.3 per cent of all the cows surveyed, and followed by the accompanying type, nervous type, and milk-fever type in the decreasing order. The frequency of occurrence of ketosis was high, or 68.9 per cent within 5 weeks after parturition and 83.4 per cent within 10 weeks after parturition. This period corresponded to a stage when milk yields were increasing.
2. When the occurrence of ketosis was examined by month, the absolute number of affected cows was the largest in March. The rate of affected cows to parturient ones was the highest in February, which was followed by April and March. It was the lowest over a period from July to September.
3. When the occurrence was analyzed by the number of pregnancies, it was of high frequency among cows which had a history of 3 to 5 pregnancies and had shown the highest milk yields and among primiparous cows.
4. As clinical symptoms of bovine ketosis, depression, reduced milk yields, diarrhea, and mammary edema were observed in the digestive type, and excitement, disturbance, and hind-quarter paralysis in addition in the nervous type. The accompanying type of ketosis was induced after the development of s ome digestive or urinary disease
5. The appearance of ketone body in the urine was the most marked immediately after parturition. It was almost parallel to the severity of symptoms. In the case of ketosis appearing 8 weeks or more after parturition, however, outstanding symptoms were manifested, though the apperarance of ketone body was most strongly positive. 6. Some cases of bovine ketosis were cured successfully after treatment had been given 1.8 times on the average. It was difficult, however, to cure 5.7 per cent of the cases treated. These incurable cases were found particularly often among those of accompanying and milk-fever types.
7. Ketosis exerted influence upon the ovarian. function. When it lasted long, the ovary underwent atrophy and dysfunction and the ovulation was disturbed. The average time interval between breeding and conception was 21 days longer than that in the healthy normal cows. There was a tendency that ovarian diseases occuryed rather frequently among cows affected with ketosis.
抄録全体を表示