|Schultz, J -|
|Gasbarre, L -|
|Shelton, T -|
|Nordstrom, S -|
|Hutcheson, J -|
|Van Campen, H -|
|Engle, T -|
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 1, 2012
Publication Date: June 1, 2012
Citation: Schultz, J.S., Carroll, J.A., Gasbarre, L.C., Shelton, T.A., Nordstrom, S.T., Hutcheson, J.P., Van Campen, H., Engle, T.E. 2012. Effects of gastrointestinal parasites on parasite burden, rectal temperature, and antibody titer responses to vaccination and infectious bovine rhinotracheitis virus challenge. Journal of Animal Science. 90(6):1948-1954. Interpretive Summary: A collaborative study was conducted involving scientists from the Livestock Issues Research Unit and Colorado State University to evaluate the potential differences in the physiology and immune response of calves that were dewormed prior to, or simultaneously to, being vaccinated. Specifically, the objective of the present study was to determine whether the timing of anthelmintic administration relative to vaccination influences antibody titer response to vaccine components, and rectal temperature and antibody titer response post an intranasal Infectious Bovine Rhinotracheitis Virus (IBRV) challenge. Results from this study indicate that deworming colostrum deprived Holstein bull calves two weeks prior to, or at the time of vaccination, reduced parasite burden and rectal temperature response following an IBRV challenge. However, timing of deworming relative to vaccination had no impact on titers to viral vaccine components, or cytokine response or to the viral challenge. Further studies are needed to gain a more fundamental understanding of the relationship between parasite burden and vaccine efficacy in regards to the immunological associations and economic implications to cattle production. The results of this research will be of particular interest to scientists working in the field of dairy calf health, development of improved vaccination, and health management processes, as well as dairy calf producers in general.
Technical Abstract: Thirty-three colostrum deprived Holstein bull calves (initial BW of 131 ± 4.0 kg) were utilized to determine the impact of timing of anthelmintic administration relative to vaccination on antibody titer response to vaccine components. Colostrum deprived bull calves born at a single dairy were utilized to ensure calves were sero-negative for antibodies specific to vaccine components. When all bull calves were at least three months of age they were randomly sorted into individual pens and placed into one of three treatment groups (n = 33). Treatments consisted of: 1) dewormed 2 wk prior to vaccination (DPV); 2) dewormed at the time of vaccination (DV); and 3) Control – not dewormed (CONT). All treatments were inoculated with infective larvae of brown stomach worms (Ostertagia ostertagi) and intestinal worms (Cooperia spp.) on d 1, 7, 10, 14, and 18 for a total dose of 235,710 infective larvae per calf. Calves (DPV and DV) were dewormed with a 10% fenbendazole suspension at 5 mg/kg BW. The DPV group was dewormed two wk prior to vaccination. On d 35, all treatments were vaccinated and DV calves were dewormed at the time of vaccination. Weekly fecal egg counts, blood, and rectal temperatures were collected throughout the experiment and feed intake and health status were recorded daily. Blood samples were obtained weekly to determine serum neutralizing antibody titers to IBR, BVDV 1, BVDV 2, and PI-3 and cytokine levels for IL-4, IL-6, TNF-alpha, and IFN-gamma. There was a tendency (P < 0.09) for CONT calves to have higher IL-4 concentrations. By design, control animals had greater (P < 0.01) fecal egg counts during the experiment. All treatment groups developed antibody titers to IBR, BVDV 1, BVDV 2, and PI-3 by d 15 post vaccination. On d 88, all calves were challenged with IBR (4 ml of 1.8 x 100 million CCID) and blood samples were obtained on d 0, 1, 3, 4, 6, 8, 10, and 12 post inoculation. Post IBR inoculation animals in all groups had elevated (P < 0.01) rectal temperatures. The CONT group had greater (P < 0.05) rectal temperatures than DPV and DV on d 88, 89, and 97. All treatment groups developed increases in SN titers for IBR, BVD, and BVD II following the IBR challenge. Additionally, all treatment groups had increased rectal temperatures during the final 7 d of the IBR challenge. Therefore, it can be concluded that deworming prior to or at vaccination reduced parasite burden and decreased rectal temperature elevation following an IBR challenge.