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Updated: Apr 11, 2026

Sperm Collection of Differential Quality Using Density Gradient Centrifugation
Published on: November 29, 2018
Effect of the presence of hens on roosters sperm variables
S G Dávila1, J L Campo2, M G Gil2
1Dpto. Mejora Genética Animal, INIA, 28040 Madrid. Spain sgdavila@inia.es.
Abstract:
This study examines the effect of the presence of hens on sperm variables in Black Barred Andaluza roosters (which respond well to the massage technique). Between 8 and 22 weeks of age, roosters (n = 60) were housed separate from hens in straw litter pens (4 birds/m(2)). Two groups of roosters were then formed to study the effect of hen presence on sperm variables at 36 weeks of age. The first group (n = 11 roosters) was housed with hens (n = 55; sex ratio 1:5), while the second (n = 27 roosters) was again housed separate from hens. Twenty four sperm pools were obtained over 12 weeks (12 pools from each group, each pool produced by mixing semen from 11 males) for analysis. Compared to the no-female-contact group, the roosters living with hens showed significantly (P < 0.05) reduced percentages of non-progressive motile sperm and slow sperm, and significantly increased VCL and VSL values; they also showed trends (P < 0.1) towards increased progressive motility and a higher percentage of rapid sperm. The presence of hens had no significant effect on the number of spermatozoa per ejaculate or sperm concentration. Positive correlations were recorded between VSL and VCL, and between both of these and progressive motility, and the percentage of rapid sperm. In addition, both VSL and VCL correlated negatively with non-progressive motility and the percentage of slow sperm. These results indicate that rooster sperm quality, but not quantity, improves in the presence of hens.
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