Effect of Refractoriness to Long Photoperiod on Sperm Production and Quality in Tomcats

Abstract

ContentsThe aim of this study was to assess whether refractoriness to long photoperiod (LP) could be reversed by subjecting tomcats to a period of short days. Our hypothesis was that photoperiod changes can avoid refractoriness and restore sperm quality and production to that before refractoriness. Tomcats (n = 6) were housed in a conditioned room with LP (12L: 12D) for 45 days of acclimation and then maintained under LP for 18 month. Then, tomcats were changed to a period of decreasing light at a rate of 8 min/day for 1 month. Tomcats stayed for 1 month with short photoperiod (SP; 8L: 16D) and then were switched back to a period of increasing light at a rate of 8 min/day for 1 month. The experiment was completed after tomcats remained in LP for 2 months. Toms were anaesthetized and semen samples were collected by electroejaculation every 2 weeks. Sperm parameters were evaluated in all ejaculates, and data were analysed by ANOVA. Motility, velocity, volume, sperm concentration, total sperm count, viability, acrosome integrity, plasma membrane integrity and sperm morphology were higher during LP compared with a refractory LP (p < 0.01). Likewise, velocity, viability, acrosome integrity, plasma membrane integrity and sperm morphology were higher in a LP compared with a SP (p < 0.05). On the other hand, motility, volume, concentration and total sperm count were similar between LP and SP (p > 0.20).Whereas motility, velocity, viability, acrosome integrity and plasma membrane integrity were similar in a refractory LP compared with SP (p > 0.05), volume, sperm concentration, total sperm count and sperm morphology were lower in a refractory LP compared with SP (p < 0.05). In conclusion, refractoriness and reduced sperm production and quality induced by a prolonged LP of 18 month can be restored after placing tomcats to a SP.

Relationship between semen quality and seminal plasma cholesterol, triacylglycerols and proteins in the domestic cat

“…The study performed by Zambelli et al was carried out from January to June, 5 while the tom cats in our study were placed in a controlled environment with an alternated photoperiod to maintain SQ. 24 Considering that sperm production and semen quality in tom cats is influenced by the season, differences between the studies could be related to different seasonal protein expression in cat seminal plasma. 1,2 In this regard, seasonal variation in SQ has been widely described in rams, and differences in seminal plasma protein composition were found between the breeding and non-breeding seasons.…”

“…An artificial illumination schedule was established with alternated 2-month photoperiod cycles to maintain SQ with 1400 lumen LED lamps giving 150–300 lux at floor level. 24 A physical examination was performed in all animals weekly, and behavioral, food and water intake, and fecal changes were recorded daily.…”

“…Data regarding the SQ of GSQ toms agree with previous reports. 24,29,30 In the PQS group, sperm PMI was not evaluated by CFDA-PI because of insufficient sperm VOL.…”

Alternative methods for feline fertility control

“…24 During the period of melatonin suppression, feline sperm parameters were similar to those previously reported during the non-breeding season 35 and during the photorefractory period. 36 After 120 days, semen parameters started to increase and reached pre-implant values at approximately 140 ± 7 days after implant insertion. 24 Conversely, ejaculate volume (0.15 ± 0.02 ml) and serum testosterone concentrations (1.1 ± 0.1 ng/ml) did not differ between melatonin-treated and control tom cats.…”

Parámetros seminales y hematológicos en gatos domésticos inmunocastrados mediante una vacuna contra GnRH

“…Se utilizaron siete gatos adultos de dos a cinco años, clínicamente sanos, pertenecientes a la colonia reproductiva de la Cátedra de Reproducción Animal. Los animales se alojaron en jaulas individuales (0,75 x 1,5 x 2 m), bajo fotoperiodo de ciclos alternos para mantener la calidad de semen (Nuñez Favre et al, 2012) y fueron alimentados con alimento balanceado premium (Balance Control de pH, Vitalcan, Argentina) y agua ad libitum.…”