|Budget Amount *help
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1995: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1994: ¥1,400,000 (Direct Cost: ¥1,400,000)
Most commonly, mastitis begins as a result of penetration of bacteria through the teat canal into the interior of the gland. Therefore, morphorogical differences of the teat shoud be related to the infection. In this research, teat measurements and ultrasonic tomography were applied to evaluate the teat morphology related to milk quality and bacteria.
Teat-base and -apex diameter, -length, teat canal diameter and -length and teat gradient were measured. At the same time, milk quality (electronicconductivity, CMT and somatic cell counts) and bacteria were examined. These parameters were compared between the positive and negative groups divided from the result of milk mastitis tests and bacteriological examination.
The teats of the same materials were examined on ultrasonography by the water bath dipping method. They were then compared with macroscopic and histopathologic findings.
Teat gradient and teat canal diameter were significantly larger in the positive group than in the negative group. The teat canal diameter of the positive group in bacterial examination was significantly larger than that in the negative group. These results suggest that the teat with larger teat grandient and/or teat canal diameter is susceptible to mastitis.
The ultrasonograhic images of normal teats were recorded that the epidermis of teat wall, intima and rosette of Furstenberg appeared as hyperecogenic, the muscle layr as hypoechogenic and the teat sinus and teat canal as anechogenic. Abnormal findings were obtained as follows, obstruction of teat sinus, hypertrophy of intima, abscess and polyp. These abnormalities were confirmed by morphological examination. In the lactating cows, some abnormal teats were found as diverticulum, stenosis and malformation.
Teat measurements and ultrasonography will be a useful methods for preventing mastitis.