Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2001-10-3
pubmed:abstractText
The aim of this study was to determine whether the sexual activity of local male Creole goats in subtropical Mexico can be induced during the non-breeding season by a long-day treatment followed by insertion of two melatonin implants. The experiment was carried out in the Laguna region in the State of Coahuila, Mexico (26 degrees N). Fourteen male goats were allocated to two balanced groups (n = 7 each) according to body and testicular weights. Males were kept together in two separate groups and fed lucerne hay for ad libitum intake and 300 g of commercial concentrate and had free access to water and mineral blocks. The control group remained in open sheds under natural photoperiod and ambient temperature conditions. The experimental group was placed in a light-proof building and exposed to 2.5 mo of long days (16 h of light/d) from November 1 to January 15. On January 16, each male received two s.c. melatonin implants and was exposed to natural photoperiodic changes in an open shed. In the control group, testicular weight exhibited seasonal variations; the highest value occurred on May 30 (146 +/- 10 g). Treated males reached maximum testicular weight earlier (March 15; 147 +/- 11 g), and sperm quality from January to March was higher than that observed in the control group (P < 0.05). Treatment caused an increase in LH pulse frequency (2.0 +/- 0.5 vs 0.3 +/- 0.2 pulse/8 h in February, 4.6 +/- 1.1 vs 0.1 +/- 0.1 pulse/8 h in March; experimental vs control group, respectively). In the control group, plasma testosterone remained low until mid-June and increased thereafter to remain elevated until the end of the study. In the experimental group, elevated plasma testosterone was observed from February to April and from July to November. Treating male goats in subtropical latitudes with artificial long days and melatonin can induce an intense sexual activity during the natural nonbreeding season.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-8812
pubmed:author
pubmed:issnType
Print
pubmed:volume
79
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2245-52
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Induction of sexual activity of male creole goats in subtropical northern Mexico using long days and melatonin.
pubmed:affiliation
Departamento de Ciencias Médico Veterinarias, Universidad Autónoma Agraria Antonio Narro, Carretera a Santa Fe y Periférico, Torreón, Coahuila, México. delgadil@ul.uaaan.mx
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't