To clarify the relationship between follicular wave dynamics and superovulatory response, we used ultrasonography to examine the follicles from Day 2(Day 0 = day of estrus) to the day before the superstimulatory treatment in 15 Holstein heifers. The heifers were divided into a CIDR group and Non-CIDR group. The numbers of corpora lutea (CLs) and remaining large follicles were counted on the day before embryo recovery. Highest and lowest numbers of small follicles were seen on Day 4 and Day 12, respectively in the CIDR group, and on Day 6 and Day 10 in the Non-CIDR group. In both groups, the number of small follicles on the day before the superstimulatory treatment was significantly and positively correlated (CIDR group: r=0.897,P<0.05; Non-CIDR group: r=0.904, P<0.01) with the total number of CLs and remaining large follicles. Peripheral estradiol-17β concentration at the time of embryo recovery was not signifi cantly correlated with either the number of remaining follicles or the quality of embryos. These results suggest that the superovulatory response could be predicted by the number of small follicles, and that CIDR insertion is effective for synchronization of the follicular wave.

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This study was conducted to evaluate the effect of administering a pasty calcium product (PCa, main component Calcium propionate) on postparturient hypocalcemia in dairy cows. In the treatment group, PCa was administered p.o. to the cows before calving (1st dose) and 12 hours later (2nd dose). Blood samples were collected 3 days before expected calving, just before the 2nd dose (12 hours later in the control group), and 1, 2, and 3 days after calving. The incidence of hypocalcemia was 29.4% and 44.4% in the treatment group and the control group respectively. The number of animals treated for hypocalcemia was also less in the treatment group. The total serum calcium concentration declined in both groups post parturition, but its recovery was more rapid in the treatment group than in the control group. No adverse response associated with PCa administration was observed. The results demonstrate that this calcium product is effective in safely preventing postparturient hypocalcemia.

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In this report, we described the clinical and pathological features of two dairy cows showing clinical signs of congestive heart failure. Case 1,a 2-year-old Holstein, showed anorexia, subcutaneous edema of the brisket, and bilateral jugular vein distension. Electrocardiograms showed decreased amplitude of the QRS complex. Echocardiography revealed markedly dilated cardiac chambers and poor left ventricular contractility. The clinical diagnosis based on these observations was dilated cardiomyopathy. Necropsy revealed thin ventricular free walls, and dilation of atrial and ventricular chambers. Microscopic examination of the heart showed enlargement, and vacuolar degeneration of myocytes and interstitial fibrosis, which coincided with the lesions of dilated cardiomyopathy, and this confirmed the diagnosis of dilated cardiomyopathy. Case 2,a 3-year-old Holstein, showed anorexia, subcutaneous edema of the brisket, and bilateral jugular vein distension. Echocardiography revealed left ventricular dilation, increased aortic root diameter, right ventricular diastolic insufficiency arising from myocardial effusion, and lack of coaptation of the aortic valve cusps. Pathological examination of the heart showed left ventricular dilation, increased aortic root diameter, and thickening of the cusps of the aortic valve associated with myxomatous degeneration. The clinical diagnosis based on these observations was aortic valve insufficiency.

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We reported on the examination and treatment of osteochondrosis with subchondral bone deficit in a Japanese black calf. The 41-day-old calf had severe pain, swelling and heat sensation in the right forelimb carpus, and it could not bear weight on the limb. The calf showed a radiolucent area of diameter about 1cm from the proximal end of the third metacarpal bone of the right forelimb in X-ray examination. The synovial fluid was turbid, but bacteria were not observed. Based on these results, we diagnosed osteochondrosis with subchondral bone deficit. On Day 3 after admission, the joint was washed with saline solution, and an anti-inflammatory drug was injected into the joint, but this did not alleviate the symptoms. As an enlarged lesion was observed in X-ray examination on Day 39, curettage and washing were performed through arthroscopic surgery, and intra-articular weekly injections of hyaluronate sodium were adminis tered for 1 month. After the arthroscopic surgery, there was gradual improvement in the symp toms, and repair and osteogenesis in the lesion were seen in X-ray examination on Day 67.

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Twin births in the dairy cows have been increasing recently. Carrying and calving twins is an excessive physiological burden. In this study, the cows were divided into two groups, those with a twin (Twin group) and a single calving (Single group), and the changes in their BCS, body weight, weight change rate (WCR) and body mass index (BMI) during the perinatal period were investigated. Furthermore, to evaluate the effect of twin calving on repro ductive performance, the duration of gestation, stillbirth rate, days to first AI, first AI conception rate, and culling-death rate of the two groups were compared. BCS and WCR between 2 and 1 months before parturition showed increase in the Single group but not in the Twin group. The Twin group had lower BCS than the Single group throughout the observation period. BMI was lower in the Twin group than in the Single group during 1 to 2 months post parturition. Gestation was shorter and stillbirths were more in the Twin group compared to the Single group. Furthermore, after parturition, the first AI was delayed, the first AI conception rate was lower,and the culling-death rate was higher in the Twin group. The results indicate that the cows with twins did not get their higher energy requirement before parturition. It is suggested that the individual management of feeding of cows with twins, such as feeding more, and feeding good quality forage in the late dry period, is important to reduce the physiological burden during the prenatal period.

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