To estimate secondary production of grazing pasture by breeding Japanese Brown cows, the method was investigated. The digestible energy (DE) requirements and animal productive energy for pregnancy and lactation were estimated by the existing formula and parameters. When the relationship between these estimated values and the practical DE intake and live weight gain has been considered, the both values corresponded well with energy balance. And it was shown that this method is available to calculate the DE requirement for maintenance which is important for grazing management of the breeding cows. These results suggested that this method can comprehend the out line of energy balance in the breeding cows under grazing and the results obtained by this method may be useful for the estimation of secondary production and for the management of pasture grazing by the breeding cows.

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A total of 353 breeding records, including 168 milking cows for five years (1983-1988), were obtained from 8 dairy farms near Yamaguchi city. The sizes of herd for each farm ranged from 10 to 25 cows.
The results were classified into four types according to the postpartum ovarian activity; type I, normal cows; type II, cows having functional corpus luteum and the follicule larger than 15mm in diameter during the luteal phase of estrous cycle; type III, cows with follicular cyst; type IV, cows with cystic corpus luteum, and then the 353 records were assigned to 138 (39.1%) for type I, 96 (27.2) for type II, 86 (24.4%) for type III, and 33 (9.3%) for type IV.
The numbers of times for A.I. based on the conception rate were 1.3, 1.6, 1.7, 1.8 for type I, II, III, IV, respectively. The percentages (%) of cows culled for sterility were 0 of type I, 4.2 for type II, 24.4 for type III, and 27.3 for type IV, and the latter three types were significantly high as compared with type I, (P<0.05) .
On the one hand, 161 breeding records were also obtained from 88 dairy cows, which were officially tested for milk yield through their life by the qualified association, were classified according to the same category and described above, being 82 (55.0%), 37 (24.8%) and 30 (20.1%) for type I, II, and III, respectively. The mean values for calving intervals (day) and total milk yield (kg) in these cows were 389.9 and 7876.7 for type I, 412.5 and 8501.7 for type II, 473.6 and 9809.2 for type III, and type III was significantly high (P<0.01) in comparison with the other two types. The average daily milk yield (kg) in the calving intervals for type I, II, III were 20.3, 20.7, 20.8, respectively, and no difference was found in the milk yield among the three groups. There was also no significant difference in the variation of daily milk yield between the types.

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1. Five experiments were conducted with goats to examine the influence of fineness of ground Italian Ryegrass hay on its digestibility and voluntary intake. In experiment 1, 2, 3 and 4, goats were fed ad tibitum with long hay, coarsely ground hay (4 mm screen), medium ground hay (2 mm screen) and finely ground hay (1 mm screen), respectively, and in experiment 5, were restricted to about one-half of hay intake in experiment 1.
2. The daily mean voluntary intakes were not significantly different among long hay (except in experiment 5) and ground hays, but tended to be depressed slightly with increasing the fineness of ground hay.
3. The digestibilities of crude protein (CP), ether extract (EE) and nitrogen free extract (NFE) were not correlated to the fineness of ground of hay, but were correlated to their respective contents of rations.
4. The digestibility of crude fiber (CF) was correlated negatively to the fineness of particle size of feses, but was not correlated to dry matter (DM) intake, content of acid detergent lignin (ADL) and fineness of ground of hay.
5. It was suggested that the digestion of CP, EE and NFE were related to their respective contents of rations, and the digestion of CF was related to the fineness of particle size of digesta.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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