Abstract
Objective - To develop a model to evaluate the effect of vaccination against Tritrichomonas foetus on reproductive efficiency in beef herds. Sample Population - A beef herd of 300 cows and 12 bulls (8 bulls ≤ 3 years old and 4 bulls > 3 years old). Procedure - The model was developed by use of data for various risk factors and vaccine efficacy. The reference herd was considered to be one in which T foetus had been diagnosed and bulls were tested for T foetus before the breeding season. Five thousand iterations were run for each of 13 simulations, with each simulation representing a separate combination of risk factors. Results - In all simulations, vaccination resulted in significantly higher calving incidence than nonvaccination. Shared grazing was found to be the most significant risk factor for a decrease in calving incidence attributable to T foetus infection, followed in importance by lack of testing before the breeding season and a higher proportion of old bulls. Combinations of risk factors contributed to a loss of income of up to 22%, some of which could be blunted by vaccination. Conclusions and Clinical Relevance - Highest calving incidence is achieved when all bulls are tested for T foetus before the breeding season and all bulls with positive culture results are culled. Avoiding all risk factors is better than vaccinating, but when this is not feasible for a given herd, the results of this simulation indicate that proper vaccination can decrease economic losses attributable to abortions caused by T foetus.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 770-775 |
| Number of pages | 6 |
| Journal | American Journal of Veterinary Research |
| Volume | 65 |
| Issue number | 6 |
| DOIs | |
| State | Published - Jun 1 2004 |
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ASJC Scopus subject areas
- veterinary(all)
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Development of a simulation model to evaluate the effect of vaccination against Tritrichomonas foetus on productive effieciency in beef herds. / Villarroel, Aurora; Carpenter, Tim; Bondurant, Robert.
In: American Journal of Veterinary Research, Vol. 65, No. 6, 01.06.2004, p. 770-775.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Development of a simulation model to evaluate the effect of vaccination against Tritrichomonas foetus on productive effieciency in beef herds
AU - Villarroel, Aurora
AU - Carpenter, Tim
AU - Bondurant, Robert
PY - 2004/6/1
Y1 - 2004/6/1
N2 - Objective - To develop a model to evaluate the effect of vaccination against Tritrichomonas foetus on reproductive efficiency in beef herds. Sample Population - A beef herd of 300 cows and 12 bulls (8 bulls ≤ 3 years old and 4 bulls > 3 years old). Procedure - The model was developed by use of data for various risk factors and vaccine efficacy. The reference herd was considered to be one in which T foetus had been diagnosed and bulls were tested for T foetus before the breeding season. Five thousand iterations were run for each of 13 simulations, with each simulation representing a separate combination of risk factors. Results - In all simulations, vaccination resulted in significantly higher calving incidence than nonvaccination. Shared grazing was found to be the most significant risk factor for a decrease in calving incidence attributable to T foetus infection, followed in importance by lack of testing before the breeding season and a higher proportion of old bulls. Combinations of risk factors contributed to a loss of income of up to 22%, some of which could be blunted by vaccination. Conclusions and Clinical Relevance - Highest calving incidence is achieved when all bulls are tested for T foetus before the breeding season and all bulls with positive culture results are culled. Avoiding all risk factors is better than vaccinating, but when this is not feasible for a given herd, the results of this simulation indicate that proper vaccination can decrease economic losses attributable to abortions caused by T foetus.
AB - Objective - To develop a model to evaluate the effect of vaccination against Tritrichomonas foetus on reproductive efficiency in beef herds. Sample Population - A beef herd of 300 cows and 12 bulls (8 bulls ≤ 3 years old and 4 bulls > 3 years old). Procedure - The model was developed by use of data for various risk factors and vaccine efficacy. The reference herd was considered to be one in which T foetus had been diagnosed and bulls were tested for T foetus before the breeding season. Five thousand iterations were run for each of 13 simulations, with each simulation representing a separate combination of risk factors. Results - In all simulations, vaccination resulted in significantly higher calving incidence than nonvaccination. Shared grazing was found to be the most significant risk factor for a decrease in calving incidence attributable to T foetus infection, followed in importance by lack of testing before the breeding season and a higher proportion of old bulls. Combinations of risk factors contributed to a loss of income of up to 22%, some of which could be blunted by vaccination. Conclusions and Clinical Relevance - Highest calving incidence is achieved when all bulls are tested for T foetus before the breeding season and all bulls with positive culture results are culled. Avoiding all risk factors is better than vaccinating, but when this is not feasible for a given herd, the results of this simulation indicate that proper vaccination can decrease economic losses attributable to abortions caused by T foetus.
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UR - http://www.scopus.com/inward/citedby.url?scp=3042678982&partnerID=8YFLogxK
U2 - 10.2460/ajvr.2004.65.770
DO - 10.2460/ajvr.2004.65.770
M3 - Article
C2 - 15198217
AN - SCOPUS:3042678982
VL - 65
SP - 770
EP - 775
JO - American Journal of Veterinary Research
JF - American Journal of Veterinary Research
SN - 0002-9645
IS - 6
ER -