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Brought to you by Kansas State University
College of Veterinary Medicine - Agricultural Practices Section
February 2007 |
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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 Agricultural Practices 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
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