Immune Response and Efficacy of a New Calf Scour Vaccine Injected Once during the last Trimester of Gestation

Volume 3 - Issue 1

Tomáš Žuffa¹, Luc Durel³*, Vladimir hraška², Denisa Svitačová¹, Rosie Reyneke⁴ and Pavol Šťastný⁵

Received: October 25, 2019;   Published: November 08, 2019

DOI: 10.32474/CDVS.2019.03.000153

Full Text PDF

To view the Full Article   Peer-reviewed Article PDF

Abstract

Objectives: The objectives of this study were to 1) evaluate the immune response induced by a single dose of a brand new vaccine against neonatal calf diarrhoea (NCD) in seronegative pregnant cows and 2) verify that calves born from these cows and fed with their colostrum are immunised against pathogenic strains of Rotavirus, Coronavirus and E. coli expressing F5 adhesin.

Materials and methods: The study included 45 seronegative pregnant cows. Control animals (n=15) received a placebo and vaccinated animals (n=30) received a single dose of the test vaccine (Bovigen®Scour, Virbac, France) between 12 and 3 weeks before calving. Serological monitoring of animals was done using an ELISA test kit specific for each antigen. Within 2 hours of calving, all calves were fed with colostrum from their own mother. Newborn calves were then challenged with either an infective dose of E. coli O101:K30, F5 + before 12 hours after birth (n=15), or Rotavirus, or Coronavirus at between 5 and 7 days after birth (two groups of n=15). The calves were monitored for 7-10 days (clinical signs and excretion of pathogens).

Results and discussion: A single injection induced a potent seroconversion, which was then reflected in the concentration of specific antibodies in the colostrum, and in the serum of calves fed this colostrum. Colostrum from vaccinated animals also had significantly (P<0.01) higher antibody titres for Rotavirus (96.1% ± 1.1), Coronavirus (82.3% ± 5.8) and E. coli F5 (81.0% ± 6.8) than that from control animals (13.8% ± 2.9, 12.4% ± 2.9 and 1.4% ± 1.7 respectively). Furthermore, calves that drank colostrum from vaccinated cows had durations of diarrhoea and clinical diarrhoea scores significantly (P<0.01) lower than calves who drank colostrum from the placebo mothers. The calf mortality rate in the control groups ranged from 20% - 40%, while no mortalities were observed in calves from vaccinated cows. Calves of the vaccinated group were also less likely to excrete pathogens, had significantly shorter (P<0.01) pathogen excretion times and excreted significantly less (P<0.01) pathogen than those from the control group.

Conclusion: This study demonstrated that a single injection of the test vaccine administered to seronegative pregnant cattle 12 to 3 weeks prior to calving significantly increased colostrum antibodies against the 3 antigens contained in the vaccine. When properly fed to calves, the colostrum was highly protective against challenge by three major causes of NCD.

Keywords: Neonatal Calf Diarrhoea; Rotavirus; Coronavirus; K99; vaccine; colostrum

Abstract| Introduction| Material and MethodsTests and analyses| Results| Discussion| Conclusion| Disclosure Statement| Highlights| References|