Blood 25-hydroxyvitamin D3 concentration of Japanese Black cattle at two farms with different rearing environments, Kagoshima prefecture, Japan.

Forty-two Japanese Black cattle on two farms in Kagoshima prefecture, Japan were used in this study. The rearing style of farm A was in a dark barn with a large roof to block sunlight (n=21). The rearing style of farm B was grazing, and exposed to direct sunlight (n=21). Blood sampling was performed twice on the same cattle in August 2022 (summer) and February 2023 (winter). As the results, the serum 25(OH)D3 concentrations were significantly lower in cattle of farm A than in cattle of farm B (P<0.01), and were significantly lower in winter season than in summer season (P<0.01). These results showed that there were differences in blood 25(OH)D3 concentrations between the farms or seasons.

1,25-Dihydroxyvitamin D3 potentiates the innate immune response of peripheral blood mononuclear cells from Japanese Black cattle.

1,25-Dihydroxyvitamin D3 (1,25(OH)2 D3 ), a bioactive vitamin D, is known to regulate immune responses in mammals. However, its impact on the innate immune responses of Japanese Black cattle, which are beef cattle endemic to Japan, remains unknown. Thus, in this study, we investigated the effect of 1,25(OH)2 D3 on the immune responses of peripheral blood mononuclear cells from Japanese Black cattle. As a result, the treatment of 1,25(OH)2 D3 upregulated the expression of antibacterial peptides, bovine beta-defensin 10 (DEFB10), and lingual antimicrobial peptide (LAP), in the presence and absence of lipopolysaccharide (LPS) stimulation. Moreover, 1,25(OH)2 D3 enhanced the inflammatory responses, including C-X-C motif ligand 8 (CXCL8) and nitric oxide synthase (NOS2), while reducing the expression of anti-inflammatory cytokine IL10, leading to an inflammatory phenotype. However, in contrast to humans and mice, 1,25(OH)2 D3 did not alter the expression of tumor necrosis factor (TNF) and downregulated triggering receptor expressed on myeloid cell 1 (TREM1) with LPS treatment. These results suggest that 1,25(OH)2 D3 potentiates the innate immune responses of Japanese Black cattle, albeit with different effects and mechanisms as compared to humans and mice.

A field study on the effects of inactivated bacteria vaccine for respiratory diseases in Japanese Black calves.

This study evaluated the effects of vaccination for Pasteurella multocida, Mannheimia haemolytica, and Histophilus somni in young Japanese Black calves at an ordinal farm, where respiratory diseases frequently occur at a young age. In total, 105 calves were divided into the vaccination group (n = 52), which received inactivated combined vaccine at 0 and 2 weeks of age, and the control group (n = 53), which received no vaccine. From both groups, eight calves each were randomly selected to determine the antibody titers. And, the incidence of respiratory disease and medical costs (treatment plus vaccination costs) were recorded for each group from birth to 16 weeks of age. In the vaccination group, the antibody titers against P. multocida, M. haemolytica, and H. somni were significantly higher than those in the control group after 8, 12, and 4 weeks of age, respectively (p < 0.05). The incidence of respiratory disease was significantly lower in the vaccination group compared to the control group (p < 0.01), and the medical costs per calf in the vaccination group were 46.4% lower than in the control group. These results might contribute to establishing an effective vaccination program against respiratory diseases in calves at each farm.

Evaluation of antibody response to inactivated bovine ephemeral fever virus vaccine for Japanese Black calves in the field.

The purpose of this study was to investigate the antibody response to the bovine ephemeral fever virus (BEFV) vaccine in Japanese Black calves. Twenty-eight Japanese Black calves, which were raised on an ordinal farm, were divided into two groups. Fifteen calves received the inactivated BEFV vaccine at 12 and 16 weeks of age (vaccination group), and 13 calves did not receive the vaccine (non-vaccination group). Blood samples were obtained at 0, 4, 8, 12, 16, 20, 24, 28, and 32 weeks of age. As the results, in the vaccination group, the antibody titers at 16, 20, 24, 28, and 32 weeks of age were significantly higher than those at 0, 4, 8, and 12 weeks of age (p < 0.01). Additionally, antibody titer in the vaccination group increased after 16 weeks of age and showed a significantly higher level than that in the non-vaccination group throughout the remaining experimental period (p < 0.01). These results might be helpful in establishing a vaccination program against BEFV in calves.