Effect of supplemental vitamin E on antibody titer in Japanese black calves vaccinated against bovine herpesvirus-1

Effects of vitamin E supplementation on serum oxidative stress biomarkers, antibody titer after live bovine respiratory syncytial virus vaccination, as well as serum and fecal immunoglobulin A in weaned Japanese Black calves

The purpose of this study was to determine the effects of vitamin E supplementation on blood oxidative stress biomarker in weaned calves. Thirty clinically healthy 12 weeks of age Japanese Black calves were randomly assigned to two groups: 15 calves received 300 IU of vitamin E daily from 12 to 18 weeks of age (VE group), and the other 15 calves did not receive the vitamin E (control group). Blood samples were taken at 12, 14, 16, 18, and 20 weeks of age. The concentration of serum reactive oxygen metabolites at 20 weeks of age were significantly lower in the VE group than those in the control group. Vitamin E supplementation to weaned calves might affect blood oxidative stress.

Effect of Beta-Carotene Supplementation on the Peripheral Blood Leukocyte Population in Japanese Black Calves

The purpose of this study was to determine the effect of beta-carotene supplementation to Japanese Black calves on the peripheral blood leukocyte population. Twenty-two Japanese Black calves were alternately assigned to two groups. Eleven calves received 20 mg/d of beta-carotene orally from 2 to 8 wk of age (BC group), and the other 11 calves did not receive (control group). The serum beta-carotene concentration in the BC group at 4, 8 and 12 wk of age were significantly higher than those in the control group (p<0.05). The numbers of CD4⁺ cells in the BC group were significantly higher than those in the control group at 4 wk of age (p<0.05). These results confirmed that beta-carotene supplementation to Japanese Black calves affected the peripheral blood leukocyte population.

Evaluation of BHV-1 antibody titer in a cattle herd against different BHV-1 strains

Although modified-live multivalent vaccines, such as PregGuard GOLD and Bovi-Shield Gold, have been used routinely in both beef and dairy cattle in the US, abortion and respiratory diseases still occasionally occur following vaccination. To determine whether the antibody induced by the multivalent vaccine can recognize BHV-1 isolates from aborted animals, BHV-1 antibody titer was evaluated with two isolates from abortion cases and two vaccine BHV-1 viruses. Cattle serum was collected from a dairy herd that was vaccinated annually with Bovi-Shield Gold 5 vaccine. Among the 28 cattle tested, no statistical significant difference in serum neutralization titer was observed when test virus was either vaccine virus or clinical isolates. It suggests that the BHV-1 antibody from the vaccinated cattle can recognize both the vaccine virus and clinical isolates. However, it is noticed that cows at 5 years old or older had a significantly lower BHV-1 antibody titer on average than the average of SN titer in 3 year-old cows. Similarly, cows at 5 years or older had a significantly lower BVDV antibody titer than cows at about 2 years of age. In addition, cattle vaccinated within 0-2 months had a significantly higher BHV-1 titer than those that received vaccination 6 months or greater prior to titer measurement. In contrast, cattle that received a vaccination 6 months prior had a significantly higher anti-BVDV antibody titer than those vaccinated within 1-2 months. The BVDV antibody titers remained relatively unchanged between 6 months and 1 year post-vaccination. Our study suggests little antigenic variation exists between BHV-1 disease isolates and BHV-1 of the multivalent vaccines. In addition, BHV-1 antibody titer is relatively lower at 6 months post vaccination in those tested animals. However, the BVDV antibody titer remained relatively high after 6 months from time of vaccination.

Effect of supplemental vitamin E on the peripheral blood leukocyte population in Japanese Black calves

We investigated the effect of supplemental vitamin E on the peripheral blood leukocyte population in Japanese Black calves. Twenty-six calves kept at the same farm were studied. They were divided into two groups; thirteen calves received 300 IU/day of vitamin E orally from 1 to 3 months of age (VE group), and the other thirteen calves did not receive the vitamin E supplement (control group). The VE group showed a higher serum vitamin E concentration at 2 and 3 months of age compared with the control group (P<0.01). The numbers of CD3⁺ cells and CD4⁺ cells were higher in the VE group than in the control group, and the difference was statistically significant at 3 months of age (P<0.05). The numbers of CD21⁺ cells were higher in the VE group than in the control group, and the difference was statistically significant at 2 months of age (P<0.05). The numbers of CD335⁺ cells tended to be higher in the VE group than in the control group. The numbers of CD8⁺ cells and CD14⁺ cells tended to be higher in the VE group than in the control group at 3 and 4 months of age. This study demonstrated that the supplementation of suckling Japanese Black calves with vitamin E might affect the numbers of some immune cell types in the peripheral blood.