Testicular Measurements and Daily Sperm Output of Tori and Estonian Breed Stallions

Abstract

Kavak A, Lundeheim N, Aidnik M, Einarsson S: Sperm morphology in Estonian and Tori Breed stallions. Acta vet. scand. 2004, 45, 11-18.-The standard procedure for assessing the breeding potential of a stallion includes the parameter total number of spermatozoa classified as morphologically normal. This study investigated sperm morphology of fresh semen in randomly chosen Estonian (E, n=8) and Tori (T, n=7) breed stallions with proven fertility. Two ejaculates were examined from each stallion. An aliquot from each ejaculate was fixed in 1 mL formol-saline immediately after collection and examined with phase-contrast microscope at a magnification 1000x for all types of morphological abnormalities. Furthermore smears were prepared and stained according to Williams (carbolfuchsin-eosin) for a more detailed examination of the sperm heads with light microscope at a magnification 1000x. Analysis of variance was applied to the data, and results are presented as LSmeans (±SE). One T stallion that had a disturbance in the spermatogenesis and one 22-year-old E stallion were not included in the analyses. The T stallions had on average 57.5±4.1% and the E-stallions 74.4±3.8% morphologically normal spermatozoa (p=0.012). In 4 of 7 T stallions and 7 of 8 E stallions both ejaculates had >50% morphologically normal spermatozoa. There was a significant difference between breeds in mean percentage of proximal droplets (17.3± 2.7% and 2.9±2.5% for T and E stallions, respectively; p=0.003). semen; sperm morphology; horse.

Sperm Production and Sperm Morphology of Swedish Warmblood Stallions

“…The DSO, calculated as the mean of TSN of days 8–10 was 6.4 × 10 9 . These findings are similar to earlier studies on full‐size horses like Thoroughbred stallions (Sullivan and Pickett 1975) and Tori breed stallions (Kavak et al. 2003).…”

“…(2002), collecting and evaluating total spermatozoa number (TSN) per ejaculate found that DSO determinations can begin as early as day 5 for stallions with smaller testes, and day 6–7 for stallions with larger testes. Kavak et al. (2003), collecting one ejaculate per day for 10 consecutive days found that TSN decreased successively from day 1 to 8 in full‐size horses, and from day 1 to 4 in small‐size horses, thereafter remaining approximately at the same number.…”

Triplex Doppler evaluation of the testes in dogs of different sizes

“…The measurement of testicular volume showed that the left testis is significantly larger than the right one, which was also observed in bulls (Kavac et al 2003) and dogs (Souza et al 2012), demonstrating in that specie an assymetry between right and left sides.…”

Fundamental Studies of the Reproductive Biology of the Endangered Persian Onager (Equus hemionus onager) Result in First Wild Equid Offspring from Artificial Insemination1

“…Testis volume has been correlated to total sperm output in the domestic horse [37]. Average volume in the Persian onager (300 cm 3 ) was comparable to those of the domestic horse [69] and donkey [70] and more than twofold greater than that reported for the Cape Mountain zebra (135 cm 3 ) [3] or Przewalski's horse (150 cm 3 ) [7]. These marked species variations in testis size may be related to inherent differences in mating system.…”