Expression and single nucleotide polymorphisms of vitamin D receptor gene in cows with puerperal metritis in Egypt.

The aim of this work is to study the expression profile of the vitamin D receptor (VDR), 1-α hydroxylase enzyme, and chemokine regulated on activation normal T-cell expressed and secreted genes (RANTES) genes in dairy cows with puerperal metritis, as well as to study the association between polymorphisms in the VDR gene and occurrence of such disease condition, which is considered a key to advances in the preventive medicine for such a problem in the future. Blood samples were collected from 60 dairy cows; from which 48 dairy cows proved to suffer puerperal metritis and other 12 apparently healthy recent parturient dairy cows were selected randomly for assessment the fold change variation in the expression profiles of the studied genes. Depending on the clinical examination, the normal cut-off point of the serum calcium, phosphorus, glucose, magnesium, potassium, sodium, and chloride, and the normal reference values of parathyroid hormone (PTH), 18 out of 48 dairy cows suffered puerperal metritis with a normal metabolic profile, which underwent further molecular analysis. In the studied dairy cows that suffered puerperal metritis with a normal metabolic profile, the expression pattern of the VDR and RANTES genes showed a significant up-regulation (P < 0.05), whereas the expression pattern of 1α-hydroxylase enzyme gene showed a significant down-regulation (P < 0.05) in comparison with those of healthy recent parturient dairy cows. The sequenced regions of the VDR gene (exon 7, partial intron 6, partial intron 7) didn't exhibit polymorphisms in their nucleotide sequence, and consecutively their amino acid sequence when compared to the published sequence on the gene bank. The results propose that the VDR gene (exon 7, partial intron 6, partial intron 7) polymorphisms do not play a role in the pathogenesis of puerperal metritis in dairy cows, excluding a role of the vitamin D in puerperal metritis.

Antimicrobial profile of multidrug-resistant Streptococcus spp. isolated from dairy cows with clinical mastitis.

OBJECTIVE: The current investigation was designed to point out the prevalence of multidrug-resistant Streptococcus spp. causing acute clinical mastitis and their pattern of antibiotic resistance in dairy cows. MATERIALS AND METHODS: Milk was sampled from 128 dairy cows with 191 infected quarters during the period from August 2017 to December 2018. Bacterial species were isolated from the milk samples and identified based on colony morphology and biochemical tests. Multiplex PCR was done for confirmatory detection of the Streptococcus spp. isolates. RESULTS: The chief isolation percentages, from the sampled milk, were Escherichia coli (26%), then Staphylococcus aureus (23%), and Streptococcus dysagalactiae (23%), then Streptococcus agalactiae (20.1%), and finally coagulase-negative Staphylococci (7.7%). In confirmed PCR streptococci isolates, the antibiotic resistance genes have been detected, including macrolides antibiotic resistance genes (ermB and mefA genes), lincosamides antibiotic resistance genes (linB gene), and tetracycline resistance genes (tetM and tetO genes). Age, parity number, cleaning of bedding materials, cleaning of milking facilities, and utensils and udder cleaning practice were significant risk factors for multidrug-resistant streptococcal mastitis in dairy cows. CONCLUSION: The results of this study explored the phenotypic and genotypic traits of Streptococcus spp. which constitute a usual cause of acute clinical mastitis in dairy cows. The ermB, mefA, tetM, and tetO antibiotic-resistant genes were identified in streptococci isolates from dairy cows' milk with acute clinical mastitis, indicating a public health hazard. Thus, veterinary clinical breakpoints are needed to improve surveillance data, improve the hygiene regimen on the farms, and promote the wise use of antimicrobials.

Effect of selenium and vitamin C on clinical outcomes, trace element status, and antioxidant enzyme activity in horses with acute and chronic lower airway disease. A randomized clinical trial.

Excess production of reactive oxygen species is involved in the pathogenesis of airway disorders in horses. Trace element antioxidants have a beneficial role in oxidant/antioxidant balance. The aim of the present study was to evaluate the effect of a combination of sodium selenite and ascorbic acid on clinical outcome, antioxidant enzymes, and trace elements status in horses with lower airway disease. For this purpose, 40 draft horses with lower airway disease were randomly selected (acute, n = 20; chronic, n = 20). Both acute and chronic cases were randomly allocated into two subgroups (ten each). Groups 1 and 2 were the horses with acute disease, while groups 3 and 4 were chronically ill. For all groups, each horse was administered antibiotic, non-steroidal anti-inflammatory, and mucolytic drug. In addition, groups 2 and 4 were injected with 15 mg/kg sodium selenite and 30 mg/kg ascorbic acid every 24 h for successive 4 weeks. Venous blood samples were obtained from diseased horses on three occasions; at first examination, and at 2 and 4 weeks post-treatment. Clinically, antioxidant supplementation improved the clinical signs with significant decrease (p < 0.05) of the clinical index score in both acute and chronic cases. In supplemented groups compared with non-supplemented, there was a significant increase (p < 0.05) in the levels of copper, zinc, selenium, and iron as well as in the activity of glutathione-S-transferase and catalase. Meanwhile, there was a significant decrease (p < 0.05) in the levels of manganese, malondialdehyde, hydrogen peroxide, and low-density lipoprotein and in the activity of glutathione reductase. The results of the present study indicate that administration of sodium selenite and ascorbic acid may have beneficial effect on clinical outcome and antioxidant balance in horses with acute and chronic lower airway disease.

Antioxidant trace elements in serum of draft horses with acute and chronic lower airway disease.

The aim of the present study was to evaluate the oxidative stress level and antioxidant trace elements status associated with lower airway disease in draft horses. For this purpose, venous blood samples were obtained from draft horses exhibiting signs of lower respiratory tract disorders (n = 83) and from control group (n = 20). Serum trace elements including selenium (Se), copper (Cu), zinc (Zn), manganese (Mn), and iron (Fe) were assayed. Serum malondialdehyde (MDA) and low-density lipoprotein (LDL) levels as well as plasma hydrogen peroxides (H2O2) concentration and activity of plasma glutathione reductase (GR), glutathione-S-transferase (GST) and catalase (CAT) were measured. There was a significant (p < 0.05) decrease of Se, Cu, Zn, and Fe in diseased horses compared with healthy ones, but the Cu/Zn ratio and Mn were increased (p < 0.05). Se was significantly (p < 0.05) decreased in chronically affected horses compared with acute cases, but Mn was increased (p < 0.05). There was an increase of MDA, LDL, and H2O2 levels and GR activity in diseased cases compared with healthy horses. However, there was a significant (p < 0.05) decrease of GST and CAT activity. MDA and LDL levels were increased (p < 0.05) in horses with chronic respiratory disease compared to acute cases, but CAT activity was decreased (p < 0.05). In horses with acute lower airway disease, there was a negative correlation between GR and H2O2 (r = -0.458), and LDL and CAT (r = -0.816). However, in chronic disease, a negative correlation was recorded between Se and MDA (r = -0.590). The results of the present study indicate that oxidative stress, with alteration of antioxidant trace element levels, is a feature of respiratory disease in draft horses.