Linked Life Data

9331862

Source:http://linkedlifedata.com/resource/pubmed/id/9331862

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1997-12-31
pubmed:abstractText
To determine the effect of prepubertal immunization against GnRH on the development of sexual and social behavior of Friesian bulls, 90 calves were randomly assigned to five treatments: 1) I2, immunized against GnRH at 2 and boosted at 2.5, 4, and 7.5 mo of age, n = 2 x 10; 2) I4, immunized against GnRH at 4 and boosted at 4.5 and 7.5 mo of age, n = 2 x 10; 3) I7.5, immunized against GnRH at 7.5 and boosted at 8 mo of age n = 2 x 10; 4) S, steers castrated at 2 mo of age, n = 10; and 5) B, intact bulls, n = 2 x 10. Blood samples were collected initially every 2, then every 3 wk. Plasma was analyzed for anti-GnRH titers and plasma testosterone concentration. Sexual and agonistic behavior, male-male mounting, and damage to paddocks was assessed throughout the experiment. All immunized calves developed antibodies against GnRH (32.3 +/- 2.0% bound at a 1:10 plasma:PBS-BSA dilution, 14 d after first boost). Plasma testosterone concentrations were < 1 ng/mL for all immunized animals until 11 mo of age, when they increased to levels found in intact bulls at 14 mo of age. At slaughter, testes and seminal vesicle weights were 38.3 and 31.6% lighter, respectively, for all immunized treatments compared to B. There were no significant differences between I2, I4, and I7.5 in any of the sexual or agonistic behavior tests. Bulls scored higher than steers in all sexual behavior tests. Immunized bulls scored lower than bulls in sexual behavior tests from 10 to 17 mo of age. The proportion of immunized animals that serviced an estrous cow was lower than the proportion of intact bulls at 10, 12.5, 14, and 17 mo of age. Immunized animals scored lower than bulls in bull challenge tests at 8.5, 11.5, 13, 14.5, and 17 mo of age. Paddock damage by animals on the three immunization treatments was lower than that by bulls from 7 to 14.5 mo of age, as were leg were scores (an indicator of male-male mounting behavior) from 9 to 14 mo of age. There was no difference in sexual behavior between immunized bulls (I2, I4, and I7.5) and bulls while held in lairage pens for 16 h before slaughter, but all treatment groups scored higher than steers. There was a similar trend for agonistic behavior, although I4 bulls were no different from steers. Prepubertal immunization against GnRH at 2, 4, and 7.5 mo of age impaired testes function and affected the development of social and sexual behavior of young bulls.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-8812
pubmed:author
pubmed:issnType
Print
pubmed:volume
75
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2609-19
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
The effect of prepubertal immunization against gonadotropin-releasing hormone on the development of sexual and social behavior of bulls.
pubmed:affiliation
Department of Biological Sciences, University of Waikato, Hamilton, New Zealand.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't