Metataxonomic Analysis of the Uterine Microbiota Associated with Low Fertility in Dairy Cows Using Endometrial Tissues Prior to First Artificial Insemination.

The deterioration in reproductive performance in association with low fertility leads to significant economic losses on dairy farms. The uterine microbiota has begun to attract attention as a possible cause of unexplained low fertility. We analyzed the uterine microbiota associated with fertility by 16S rRNA gene amplicon sequencing in dairy cows.

Effects of Intramammary Antimicrobial Treatment on the Milk Microbiota Composition in Mild Clinical Bovine Mastitis Caused by Gram-Positive Bacteria.

The purpose of this study was to clarify the effects of antimicrobial treatment for mild mastitis caused by Gram-positive bacteria on the milk microbiota in dairy cattle. Sixteen quarters of sixteen cows with mild clinical mastitis from the same herd were included in the study. On the day of onset (day 0), the cows were randomly allocated to a no-treatment (NT; = 10) group or an intramammary antimicrobial treatment (AMT) group that received AMT starting on day 0 (AMT-AMT group; = 6).

Effect of glycyrrhizin administration followed by symptom-based antimicrobial selection therapy on antimicrobial use in clinical mastitis without systemic symptoms.

In bovine mastitis, antimicrobial treatment is often initiated before the causative organism is identified a problem in the prudent use of antimicrobials. In this study, we aimed to reduce the total amount of antimicrobials used in mastitis treatment by administering glycyrrhizin, an anti-inflammatory drug, instead of antimicrobials at the onset of clinical mastitis without systemic symptoms, followed by symptom-based antimicrobial selection therapy (ST), to examine the effect of this treatment strategy on treatment outcomes and antimicrobial use. Comparisons between cases that received antimicrobial treatment starting from the day of diagnosis (blanket antibiotic therapy [BT] group: 33 cases) and cases that received ST starting from the day after the diagnosis (ST group: 57 cases) revealed no difference in the cure rate, milk withholding period, or recurrence rate.

Copy number variations in BOLA-DQA2, BOLA-DQB, and BOLA-DQA5 show the genomic architecture and haplotype frequency of major histocompatibility complex class II genes in Holstein cows.

Bovine major histocompatibility complex (MHC) class II region contains many genes. The bovine leukocyte antigen (BoLA)-DRB3 was reportedly associated with susceptibility of various phenotypes of infections including bovine leukemia virus-induced lymphoma. However, the association of the remaining genes with various phenotypes has not been clarified due to the complicated genomic structure of the MHC class II region.