Dose Standardization Studies of 'Indigenous Vaccine' for the Control of Mycobacterium Avium Subspecies Paratuberculosis in Naturally Infected Goats

摘要

Mycobacterium avium subspecies paratuberculosis (MAP) infection is most prevalent disease in Indian domestic livestock. Dose rates evaluation studies of ‘indigenous vaccine’ against Johne’s disease (JD) were conducted in naturally infected goats. Adult female goats (29) of Barbari breed (>1.5 years) poor in body condition and suffering with clinical JD were randomly divided into four groups; Goats in group I (n=6) were given 1 mL of plane adjuvant (Gerbu Biotechnik, Germany) used in the vaccine preparation, Group II (n=7) and group III (n=8) goats were vaccinated with 2.5 mg/ml/goat and 5.0 mg/ml/goat dose rates of indigenous JD vaccine, respectively, Group IV (Control, n=8) goats were given 1 ml of PBS. Vaccinated goats were monitored for overall improvements on the basis of health (morbidity), mortality, production (body weights, reproductive efficiency), physical and clinical conditions (weakness, diarrhea, skin coat, deposition of fat in visceral organs), immunological parameters (ELISA titer) and status of shedding of MAP bacilli in feces. Average of body weights gained within one year of vaccination in four groups statistically passed normality test (P value >0.1) and vaccinated goats gained higher body weights as compared to adjuvant (Group I) and control (Group IV) groups. At 360 dpv, goats in group II (2.5 mg/ml) showed higher titer of antibodies as compared to group III (5.0 mg/ml), while it varied in control group (IV). After vaccination clinical condition of goats improved (diarrhea stopped, regeneration of hairs, body coat regained luster). Kids born to vaccinated goats had higher birth weights. Comparative evaluation of two dose rates on above parameters showed that group II goats gained higher body weights (3.10±0.52 kg) and their physical conditions also improved in comparision to group III. Dose rate of 2.5 mg/ml/goat exhibited higher efficiency against JD than 5.0 mg/ml/goat. Therefore, under optimum nutritional conditions, 2.5 mg/ml/goat dose of native vaccine was optimum for the control of JD in goats endemically infected with MAP.