The antioxidant enzymes, lipid peroxidation and free radicals assessment were made of the effects of selenium, copper and magnesium on bovine endemic fluorosis under high fluoride, low selenium and low copper productive conditions. Thirty-two beef cattle were selected from high fluoride area, and randomly divided into four groups with eight cattle each as follows: (1) high fluoride control group (HFC); (2) supplemented group with 0.25 mg/kg selenium (HFSe); (3) supplemented group with 15 mg/kg copper (HFCu) and (4) supplemented group with 0.25 mg/kg selenium+15 mg/kg copper+1 mg/kg magnesium (HFSeCuMg) per day for 83 days. Moreover, eight beef cattle were selected from non-high fluoride area as normal control group. Blood samples were collected from cattle on 0 d, 30 d and 83 d respectively, to analyze the enzyme activities and concentration of GSH-px, CAT, SOD, MDA and free radicals. The results showed that the contents of free radicals and MDA in HFC group were significantly higher, and the whole blood GSH-px, CAT, erythrocyte SOD activities were lower than the normal control group. Free radicals, metabolic imbalance and antioxidant disorder therefore, play an important role in fluorosis. However, GSH-px, CAT and SOD activities in HFSe group and HFSeCuMg group at 30 d and 83 d were markedly higher than the same groups at the 0 d and the HFC group at the same time. Likewise, there was a corresponding reduction in the contents of free radicals and MDA. These findings indicated that supplementation with selenium, copper and magnesium elevated high fluoride bovine antioxidant enzymes, and decreased MDA and free radicals contents. But, the activities of supplementation selenium group did not increase until day 83. These results demonstrated that fluorosis was associated with lower serum Se and Cu levels than in the control, and it was therefore concluded that fluorosis is associated with decreased serum levels of these minerals. Long-term high fluoride intake under productive condition enhances oxidative stress in the blood, thereby disturbing the antioxidant defense of cattle. Increased oxidative stress could be one of the mediating factors in the pathogenesis of toxic manifestations of fluoride. It is benefical for high fluoride cattle supplemented with proper selenium, copper and magnesium to increase fluoride excretion and obtain the protective impact of the activity of oxidative enzymes, and to decrease lipid peroxidation and free radicals contents.

However, few studies have been performed on lymphoma, the clinical form of EBL, until now (Lim, 1969;Lee et al., 1982), and the reports on characteristics of lymphoma in the naturally BLV-infected cattle are limited in Korea. It is the purpose of this study to assess the frequency and distribution of lymphoma in the BLV-infected cattle. MATERIALS AND METHODS

ABSTRACT. To evaluate clinical effects of autogenous toxoid-bacterin treatment for Staphylococcus aureus subclinical mastitis in lactating cows, 22 cows which had at least one S. aureus infected quarter were selected from among cows at a S. aureus prevalent dairy farm. Eleven cows were injected with their own autogenous toxoid-bacterin and the others were maintained as non-injected control. In the toxoid-bacterin injected group, 27% of infected quarters were cured during the 12-week trial, compared to 5% in the control group. New intramammary infections with S. aureus were only detected in 3 quarters of the control group. Mean IgG antibody titer against S. aureus somatic antigens and α-toxin in serum and milk were significantly increased in the toxoid-bacterin injected group (p<0.05) and remained higher than those of the control group which showed no significant changes (p<0.05). In contrast to the control group, from 3 weeks after the second injection of the toxoid-bacterin injected group, mean S. aureus cfu/ml in milk samples from injected quarters with S. aureus was significantly decreased until the end of the study (p<0.05). In the toxoid-bacterin injected group, significant decreases of mean SCC were detected from milk samples from infected quarters with S. aureus from week 7 to week 10 (p<0.05). These data show that autogenous toxoid-bacterin treatment against S. aureus subclinical mastitis in lactating cows may increase the cure rate of the infections, reduce the severity of the infections and also prevent occurrence of the new infections.

A flock of Arbor Acres chickens were reared in cages and provided with high energy pelleted feed. At 14 d of age, a total of 350 birds were separated into 3 groups randomly as follows: 100 birds were exposed to ambient temperature of 20°C as a control group, 150 birds were exposed to lower ambient temperature of 11°C to induce ascites (group I), and another group of 100 birds were exposed to lower ambient temperature of 11°C and fed diet containing 1% L-arginine for ascitic prophylactic treatment (group II). Blood and tissue samples (lung and liver) were collected from chickens at 3, 4, 5, 6 and 7 wk of age subsequently, to analyze the concentration and activities of free radicals, mononaldehyde (MDA), superoxide dismutase (SOD), Nitric Oxide (NO) and Nitric oxide synthase (NOS). The results showed that the prevalence of ascites in the control, group I and group II was 3%, 9.33% and 3% respectively (p<0.01). The concentration of free radicals in the lungs of 3 wks old preascitic broilers in group I was significantly higher than in the corresponding control group (p<0.05). The concentrations of free radicals in lung and liver in the 7 wk period, and that of NO and SOD in the plasma were significantly lower in group I than in the control group (p<0.01). However, the accumulated MDA contents in group I were higher than in the control group and group II (p<0.05), respectively. In the same way, the activity of NOS in group II was higher than both group I and control group (p<0.01) during the 7 wk period. There was no significant difference between SOD activities of group II and the control group (p>0.05), and also insignificant difference between NOS in group I and the control group (p>0.05). The results of this study indicate that there was a significant decrease in the concentration of MDA in group II. On the other hand, the concentration of free radicals decreased and MDA concentration increased in group I during the 7 wk period. The reduction in concentration of MDA in group II, following arginine supplementation may be associated with the scavenging activity of NO.