Skip to the content

Kansas State University

 

Beef Research News
Brought to you by Kansas State University College of Veterinary Medicine - Farm Animal Section
February 2007

 

 

 

Contents:

Cow-Calf Retained Ownership Decision

Pregnancy percentage with sexed-semen at three uterine sites

Montana institutes Trichomoniasis testing law

Stress and Immunity in Swine and Cattle

Best Management Practices and Beef Producers

Revaccination information in cattle auctions

 

Cow-Calf Retained Ownership Decision
Cow-calf producers have the opportunity to maintain ownership of their animals beyond the traditional sale point at weaning.  Potential benefits of retained ownership post-weaning include increasing animal value through weight gain, obtaining post-weaning performance information, and capturing rewards associated with superior genetics and preventative health programs.  Possessing calves through the finishing phase also increases risk for the cow-calf producer compared to marketing at weaning due to price uncertainty at the time of sale and post-weaning performance variability.  The decision to retain ownership should be based on an understanding of current beef industry structure, an estimation of potential risks (e.g., price, health, performance), and the risk preferences of the decision maker.

White, B.J., J.D. Anderson, R.L. Larson, K.C. Olson, D.U. Thomson. Review of the cow-calf operation retained ownership decision.  Professional Animal Scientist. 2007 28: 18-28.

 

Pregnancy percentage with sexed-semen at three uterine sites
The objective of this research was to asses the effect of deposition of sex sorted semen at three different sites at a fixed time after estrus synchronization.  Heifers (n=209) were synchronized with two injections of PGF2a 14 days apart and at 80-82 hours after the second injection were inseminated with X-chromosomes bearing fractions of semen with 2.2x106 sperm per dose.  Heifers were inseminated in one of three locations: uterine body (UB-AI, n=91), intracomual deposition in the middle of the uterine horn (MH-AI, n=57), or close to the utero-tubal junction (UTJ-AI, n=61).  Overall pregnancy rage was 43.1%.  Pregnancy rages did not differ (p>0.05) among sites of sperm deposition, between two farms at which heifers were kept or between the two bulls producing the semen.  Pregnancy rates for sites of deposition were 41.8% (UB-AI), 49.1% (MH-AI), and 39.3% (UTJ-AI).  Pregnancy rate was 25% higher (P<0.01) when heifers showed strong signs of estrus at time of insemination (when pooled across deposition sites).  In conclusion, pregnancy rates of heifers did not differ significantly following deposition of 2.2x106 sex-sorted sperm 80-82 h after the second PGF2a injection near the utero-tubal junction, in the middle of the horn or in the uterine body.

Kurykin, J., U. Jaakma, M. Jalakas, M. Aidnik, A. Waldmann, and L. Majas. Pregnancy percentage following deposition of sex-sorted sperm at different sites within the uterus in estrus-synchronized heifers. 2007 Theriogenology 67(4): 754-759.

 

Montana institutes Trichomoniasis testing law
A new law requires Trichomoniasis testing of all non-virgin bulls imported into Montana as well as any that are sold, loaned or leased within the state.  The Montana Department of Livestock announced that the rule went into effect on February 9, 2007, but producers and importees are being given a grace period extending to March 16 to comply.  The regulations require bulls to be tested negative 3 times at no less than one week intervals with no breeding in between tests and the time the bull is sold, leased, or loaned.  Owners of bulls testing positive must notify neighbors and positive bulls must be slaughtered immediately or fed at feedlot until slaughter.  For additional information visit www.mt.gov/liv.

 

Stress and Immunity in Swine and Cattle
Stress is generally considered to lead to immune suppression and may increase the occurrence of disease in the presence of a pathogen.  After immune challenges the homeostatic processes, in part regulated by the hypothalamic-pituitary-axis ordinarily brings the immune system back to a baseline level.  Findings from various studies investigating the effects of stress on the immune system are conflicting and difficult to reconcile into a cohesive and comprehensible set of universally applicable theories.  These discrepancies may be partly explained by the types and durations of the stressors, the aspect(s) of immune system measured, genetics, and social status.  The balance between components of the immune system may be disrupted when a particular stressor may enhance cell-mediated responses while suppressing humoral responses (or vice versa).  Environmental stressors include not only weather related events (e.g., heat, cold, humidity, pollutants), but also animal interaction in the social environment.  Dominant animals may have enhanced immune activation, whereas subordinates have suppression of the same immune component in response to the same stressor.  A better understanding of the consequences and complex interactions between social and environmental stressors for innate and adaptive immune traits must be developed so we can fully understand the effects of stress on immunity in livestock.

Salak-Johnson, J.L. and J.J. McGlone. Making sense of apparently conflicting data: Stress and immunity in swine and cattle. J. Anim Sci. 2007. 85:E81-E88. doi:10.2527/jas.2006-538

 

Best Management Practices and Beef Producers
A survey of beef cattle producers was conducted to determine adoption rates and reasons for non-adoption of 16 best management practices (BMPs).  Practices were grouped into general categories of erosion and sediment control practices, grazing management, mortality, nutrient, and pesticide management.  Adoption rates of specific practices ranged from 19% to 75% within the survey.  Of non-adoptors, most had not adopted because of unfamiliarity with BMPs or perceived non-applicability to the farm.  Portions of producers not adopting due to high cost was relatively low.  Farm size was not a significant factor in adoption rate in this study.  These results highlight the importance of educational efforts in encouraging adoption, as well as farm type and financial situation of the farmer.

Gillespie, J., S. Kim, and K. Paudel. Why don’t producers adopt best management practices? An analysis of the beef cattle industry. Agricultural Economics 36 (2007) 89-102.

 

Revaccination information in cattle auctions
Research was performed to analyze the problem of asymmetric information between buyers and sellers in cattle auctions, specifically focusing on the challenge of revaccinations.  Revaccination by the buyer may be considered if the buyer does not know or cannot verify whether the seller vaccinated their animals.  Revaccination is only a part of the broader problem of information asymmetry that includes other quality issues and costs that can be saved.  A model is created to illustrate that information asymmetry creates inefficient outcomes.  A credible third party certification system is a viable solution to the dilemma, but the cost of the program must be less than the cost of revaccinations.

Chymis, A.G., J.S. James, S. Konduru, V.L. Pierce, and R.L. Larson. Asymmetric information in cattle auctions: the problem of revaccinations. Agricultural Economics 36 (2007): 79-88.



___________________________________________________________________
Beef Research News is produced by the Farm Animal section at Kansas State University. To modify your subscription to this service please email Erin Thomas ( ethomas@vet.k-state.edu )

For more information please contact:
Brad White
Beef Production Medicine
Q211 Mosier Hall
Manhattan, KS 66506
bwhite@vet.ksu.edu