Efficacy of Vitex pseudo-negundo in a Bovine Mastitis Model Experimentally Induced by Staphylococcus aureus in Rats.

Abstract

Background: Mastitis is one of the most prevalent and economically significant diseases in dairy cattle, causing to inflammation of the mammary gland and reduced milk yield.

Objectives: This study investigated the therapeutic efficacy of Vitex pseudo-negundo (VPN) extracts in an experimentally induced rat mastitis model.

Methods: Sixty female Wistar rats were randomly assigned into six groups of 10. Group I served as the control group. Mastitis was induced by intramammary injection of Staphylococcus aureus (SA) (1.5 × 10⁸ cfu/mL; 10 µL per gland) into the L4, L5, R4 and R5 mammary glands. Group III received intramammary gentamicin (0.25 mg/10 µL/day) for 5 days. Groups IV-VI received VPN extracts-water (0.2603 µg/kg/day), ethanol (0.0803 µg/kg/day) and petroleum ether (0.1042 µg/kg/day), administered at 10 µL per gland for the same duration. Rats were clinically monitored three times daily from the onset of clinical signs until euthanasia.

Result: SA infection significantly increased mammary gland weight, total oxidative status (TOS) and bacterial load and induced tissue pathology, while decreasing total antioxidant status (TAS). C-reactive protein levels remained unchanged. VPN significantly improved mammary gland weight, TOS, TAS, bacterial load and histological parameters (p < 0.001). Mammary gland weight, oxidative stress, bacterial load and histopathological lesion severity all decreased markedly following treatment. Histological examination showed near-normal restoration of mammary gland architecture in all treatment groups.

Conclusion: Preparations of VPN, particularly the water extract, demonstrated strong potential for restoring altered microbiological, biochemical and histological parameters in this rat mastitis model.