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Decrease in the seasonality of sexual behavior and sperm production in bucks by exposure to short photoperiodic
J A Delgadillo1, B Leboeuf, P Chemineau
1I.N.R.A. Station de Physiologie de la Reproduction Nouzilly, 37380 Monnaie, France.
Theriogenology
|November 1, 1991
Summary
Rapidly alternating light and dark cycles can reduce seasonal variations in buck body weight and sexual activity. This study explored how controlled photoperiods impact buck reproductive parameters, showing reduced seasonality in treated groups.
Area of Science:
- Animal Science
- Reproductive Biology
- Photoperiodism
Background:
- Bucks exhibit significant seasonal fluctuations in body weight and sexual activity.
- Understanding and mitigating these seasonal variations is crucial for livestock management and breeding programs.
Purpose of the Study:
- To investigate the effect of rapid alternations between long and short day photoperiods on seasonal variations in bucks.
- To determine if controlled light cycles can abolish or reduce natural seasonality in buck reproductive parameters.
Main Methods:
- Three groups of six Alpine and Saanen bucks were used over two years.
- Control groups experienced natural daylength.
- Experimental groups were exposed to either 2-month or 4-month cycles of alternating long (16L:8D) and short (8L:16D) days.
Main Results:
- Control bucks showed significant seasonal changes in body weight, sexual behavior, testicular weight, and sperm production.
- Experimental groups exhibited decreased seasonal variations in these parameters.
- Bucks under altered photoperiods produced a larger total number of spermatozoa per ejaculate compared to controls.
Conclusions:
- Rapid alternations between long and short days effectively decrease seasonality in buck sexual activity.
- Controlled photoperiod manipulation offers a potential strategy to manage and improve buck reproductive performance year-round.
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