The effect of the age of dogs on their ejaculate

Abstract

FILIPČÍK, R., VÁGENKNECHTOVÁ, M., HOŠEK, M., JARINKOVIČOVÁ, L.: The eff ect of the age of dogs on their ejaculate. Acta univ. agric. et silvic. Acta univ. agric. et silvic. Mendel. Brun., 2011, LIX, No. 3, pp. 45-50 The eff ect of the age of dogs on quantitative and qualitative parameters of the ejaculate was explored. We evaluated 43 dogs; from each dog we collected three samples on three successive days. The dogs were divided into three age categories: 1.5-2 years; 2-3 years; and 3-5 years. The maximum ejaculate volume was collected from dogs of 2-3 years of age; the average volume of ejaculate from 3 collections was 9.1 ml. Microscopic examinations of the ejaculate of this age category of dogs showed that the highest average sperm concentration was 153.62. . In older dogs the ejaculate volume decreased considerably with increasing frequency of collections (8 ml > 5 ml > 2 ml at the 3 rd collection). The amount of motile sperm was the highest in 3 to 5-year-old dogs (76%) and was related with the highest proportion of morphologically normal sperm (66.8%). However in the 3 rd collection of this age category we saw a signifi cant (P < 0.05) increase in the amount of pathologically changed sperm (29.5 < 28.8 < 41.2%), mostly in the structure of the fl agellum. Signifi cant diff erences in the quantity and quality of the ejaculate were discovered not only among the age categories of the dogs but also among the individual collections. dog ejaculate, volume of ejaculate, sperm activity, sperm concentrationThe number of breeders involved in dog breeding is relatively high. However if the owner of the dog is to be a successful breeder his dog must produce a suffi cient amount of good-quality ejaculate capable of fertilisation. The fertility of dogs can be evaluated in two ways. The breeder may wait to see if the bitch will conceive a er mating or if she gives birth to pups. However, such an approach is unprofessional; for reproduction purposes the breeder should use only dogs whose qualitative and quantitative parameters of the ejaculate had been examined. The birth of pups should be taken as the fi nal confi rmation of the fertility of the dog. DEIBEL et al. (1976), DUNPHY (1989), RIGAU et al. (2001) evaluated the basic qualitative parameters of the canine ejaculate. According to KUTZLER (2005) the optimal room temperature for ejaculate collection is 20 °C; the colour, volume, motility, concentration and morphological structure of the ejaculate should be evaluated. GUNAY et al. (2003) evaluated the sperm fraction of the ejaculate of seven German shepherd dogs. On one day the ejaculate was collected twice within 60 minutes. Between the fi rst and the second collection the authors discovered statistically signifi cant (P < 0.05) diff erences in the volume of the ejaculate and sperm concentration, but not in the motility, live sperm count and amount of morphological changes in the sperm structure. SCHAFER et al. (1997) collected canine ejaculates twice a week over a period of 6 months and they discovered si...

The influence of external and internal factors on the quality of semen collection and qualitative indicators of semen in the dog (Canis familiaris)

“…Similar values of sperm activity we found in our observation are stated also by e.g. Filipčík et al (2011), who also noticed the identical trend of sperm activity depending on the order of ejaculate collection. Also Rijsselaere et al (2002) or England et al (1999) similarly state high percentage of sperm with progressive activity (78.7; respectively 64.6-71.5%).…”

“…Although a diff erence was found in volume of ejaculate between small, medium and large dogs, there was no statistically conclusive diff erence between groups, see Tab I. Filipčík et al (2011) found similar volumes of ejaculate in three age groups, especially for dog aged 2-3 years the volumes were almost identical (11.05; 8.44, respectively 7.82 cm 3 ). Yet compared to our observations, they found signifi cantly lower volume of the whole ejaculate in older dogs -depending on the order of collection (8.00, 5.00, resp.…”

The Quality of Frozen-thawed Canine Semen With Respect to Semen Extender Composition and Sequence of Ejaculate Collection in Dogs

“…Moreover, Gunay et al (2003) did not observe the infl uence of the semen collection sequence (two collections, 60 minutes apart) on the percentage of morphologically normal sperms in native ejaculate. On the other hand, Filipčík et al (2011) detected diff erences in native ejaculate collected once a day for three consecutive days only in the oldest category of dogs between collection 1 and 3.…”

“…They also observed the same percentage of normal motile sperms when samples were collected twice with a short (approximately 60-min) interval between two collections. It seems that the motility of sperms from native ejaculate might be infl uenced rather by the age of the dog than semen collection sequence when samples are evaluated subjectively (Filipčík et al, 2011).…”

“…However, the question is whether the quality of the collected ejaculate is satisfactory for the production of cryoconserved insemination doses. There are studies describing changes in the quality of fresh ejaculate from dogs when they were collected twice in a 60-minute interval (England, 1999;Gunay et al, 2003), every alternate weekday and three days in a row (Filipčík et al, 2011). Nevertheless, studies are lacking to evaluate the relationship of the semen collection sequence and the quality of frozen-thawed semen of dogs.…”