A total of 1, 540 dairy cows were examined to determine the effects of age, milk yield, lactation stage, TDN, DCP levels and temperature regarding hematocrit values (Ht). Except for the DCP level all items affected Ht. Ht during the high temperature season was lower than in low temperature season (p<0.01). Increased water intake during the summer seemed to be one of the factors which decreased Ht.
To get corrected Ht in the summer, multiple regression analysis was performed using 4 variables relating to the Ht. Multiple correlation coefficient was 0.364 (p<0.01).
To reveal the effects of the milking stage and feeding management on Ht, it is recommended that Ht becorrected by age, milk yield and temperature

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Effects of gonadotrophin (GTH), dosage of a follicle stimulating hormone (FSH-P), repeated treatment with GTH, times of artificial insemination (AI), kinds of bull semen, age of donor and times of embryo recovery on superovulation were investigated.
Three hundred thirteen Japanese black cows and thirty-nine Holstein cows were superovulated between Day 9 and 14 (estrus=day 0) with FSH or pregnant mare serum gonadotrophin (PMSG). Prostagrandin was given 48hr after the first FSH-P injection. Forty-eight hr after the PGF₂α injection, cows were inseminated artificially 1-4 times 12 and 24hr after onset of estrus and treated with LH-RH. Embryos were collected on Day 7 post-insemination.
There was no significant difference (P<0.05) in the total number of ova/embryos (8.7±7.8 vs 8.6±7.7) and the transferable embryos (5.1±5.8 vs 4.6±4.9) between FSH-P and PMSG groups, respectively. The acceptable numbers of recovered and transferable embryos were increased using 36mg of FSH-P in Japanese black cows and 48mg in Holstein cows, respectively. The mean number of recovered embryos in the three times repeated treatment for superovulation was significantly lower (P<0.05) in third treatment than those using PMSG. The appearance rates of transferable embryos in 1, 2, 3 and 4times treatment of AI were 57, 48, 53 and 49% respectively, and that there was no significant difference (P<0.05) between insemination groups. However, appearance rates of transferable embryos in 2, 3 and 4times treatment of AI tended to be lower than the 1time treatment of AI. Although various fertilization in vivo at individual semen were found, no significant difference (P<0.05) was observed in the appearance rates of the transferable embryos among the four bulls (46, 51, 61 and 80%, respectively). The number of transferable embryos of the donor below 2 years, above 9years and 3-4 years was significantly higher (2.8±3.6, 2.6±3.2 and 5.9±5.9, P<0.05) than that of 3-4 years donor. Recovered embryos and transferable embryos tended to decrease in the July to September period when compared with other months.

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Beef cattle were examined whether there are selenium and tocopherol deficiencies during the fetal stage or not. The results are as follows: Serum selenium levels of eight Holstein calves and their dams which were fed with a diet of high-content selenium and tocopherol were higher than 35 ppb. Serum tocopherol levels of the dams were over 150μg/100ml.
Eighty-Seven decimal five % of the fetuses and calves of beef cattle which were fed with a diet of lowcontent selenium showed low serum selenium levels under 20 ppb.α-tocopherol levels in the liver of beef calves were lower than those of Holstein calves. Eighty-seven decimal five % of the dams showed low-serum selenium levels under 20 ppb. One of the beef calves that died immediately after birth showed degenerative changes in the skeletal muscles.
From the above findings, all of the fetuses and calves of the beef cattle showd deficient levels in serum selenium and tocopherol and it was suggested that the deficiencies might be caused by a lack of selenium and tocopherol intake by their dams.

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The present study describes the effects of the injection of vitamin D₃ (10×10⁶IU) on the plasma concentration of vitamin D metabolites and minerals in healthy cows during late pregnant and lactating periods. Five Holstein-Friesian cows, aged 3 to 6years, were used in the late pregnant (for 7days from 1week before expected calving) and lactating (for 7days from 12 weeks after calving) periods.
The plasma 25-hydroxyvitamin D (25OHD) concentrations in late pregnant and lactating periods began to rise significantly from 1 and 2days after the injection, respectively. The plasma 25OHD concentration in the lactating period was significantly higher than that in the pregnant period at 1day before, and 6hr and 4 days after the injection. The plasma concentration of 1, 25-dihydroxyvitamin D (1, 25 (OH)₂D) in the pregnant and lactating periods increased at 12hr and 1day after the injection, respectively. The plasma 1, 25 (OH)₂D concentrations in the lactating period were significantly lower than those in the pregnant period at 12hr and 1 day after the injection. The plasma Ca concentration in the lactating period was also significantly lower than that in the pregnant period at 1day before the injection. These results suggest that there are no differences in the effects of the vitamin D3 injection between late pregnant and lactating period, although the activity of 24, 25-dihydroxylase in the lactating period may be increased by the effect of vitamin D₃ injected during the late pregnant period.

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The sensitivity and specificity of a commercial heartworm (Dirofilaria immitis) antigen test kit were evaluated in 100 dogs with and without heartworm infections. All 25 microfilaremic heartworm-infected dogs, in which the number of heartworms ranged from 3 to 91, were identified correctly as positive (sensitivity: 100%). The test detected occult infection in 18 of 25 (72.0%) dogs. All heartworm-free dogs with (25 dogs) and without (25 dogs) roundworm (Toxocala canis) infection were indentified as negative (specificity: 100%). The accuracy in all 100 dogs tested was 93%. Changes in the circulating antigen levels after surgical heartworm removal were examined in 10 dogs using this kit. By surgical treatment, all heartworms were removed in 6 dogs, and removal efficiency ranged from 65.5 to 86.7% in the 4 other dogs. After heartworm removal, the circulating antigen levels declined in all dogs. The mean antigen level in 10 dogs was×730±1238 before removal, ×84±98 at 4 weeks after removal, ×36±39 at 8weeks after, and ×14±8 at 12 weeks after. There were no dogs in which the circulating antigen disappeared.

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During the period from July to August 1990, 80 human sera and 23 wild rat sera collected in Pohnpei, Federated States of Micronesia, wrer examined for antibodies to 14 serovars of Leptospira by a microscopic agglutination test (MAT). Five (6.3%) human sera showed a positive reaction with titers of more than 64. Of these, two had a titer of 128 to icterohaemorrhagiae or autumnalis, and 3 had a titer of 64 to autumnalis, cynopteri or wolffi. Three (13.0%) of wild rat sera showed titers ranging from 16 to 64 to castellonis, hebdomadis or icterohaemorrhagiae. No Leptospira was isolated from the kidneys of 60 rats examined.

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