The aim of this study was to compare the cryoprotective effects of egg yolk from different avian species (hen, goose and quail) on post-thaw quality of dog semen. Total motility (TMOT) and progressive motility (PMOT) of frozen-thawed spermatozoa were not significantly differed among the extenders, but were higher in the quail-egg yolk based extender compared with extender containing hen or goose egg yolk. It was found that post-thaw sperm motion parameters, velocity VCL and ALH, were significantly higher in the quail-egg yolk based extender. No marked differences in post-thaw sperm plasma membrane integrity (PMI) and mitochondrial membrane potential (MMP) were observed among the extenders. In conclusion, the results of the present study suggest that goose or quail egg yolk is a suitable alternative to hen egg yolk for the cryopreservation of dog semen.

Lipoproteins, isolated from ostrich egg yolk (LPFo), provide excellent protection for boar spermatozoa against cryo-induced damage. The present study was performed to investigate the effects of LPFo on the freezability and fertilizing capacity of frozen-thawed (FT) boar semen after post-cervical artificial inseminations (post-CAIs). Semen, collected from 7 Polish Large White (PLW) and 4 Polish Landrace (PLR), was frozen in an extender containing LPFo. Post-CAIs were performed in 38 multiparous sows, using a catheter-cannula kit. Sows were inseminated 2× within one oestrus, and fertility parameters were recorded after farrowing. Neither boar (within breed) nor breed affected the quality of the pre-freeze (PF) semen, such as total motility (TMOT), mitochondria membrane potential (MMP), plasma membrane integrity (PMI), osmotic resistance test (ORT) and DNA fragmentation. Differences in the freezability of boar semen were observed among the boars, whereas there were no marked breed effects. Post-thaw TMOT markedly declined over storage time in most of the boars, particularly at 60 min after thawing. Inseminations of post-weaned oestrus sows resulted in pregnancy and farrowing rates of 84.2% and 81.6%, respectively. Neither the mean number of piglets born (NB) nor the mean number of piglets born alive (NBA) was affected by boar or breed. The total number of piglets born was 365, resulting in 11.8 NB piglets, whereas the total number of piglets born alive was 353, with 11.4 NBA piglets per litter. The findings of this study reaffirm the variations in the freezability of boar semen. In this study the supplementation of ostrich egg yolk lipoproteins to the freezing extender of boar semen produced high proportions of functionally viable FT spermatozoa that were capable of providing acceptable fertility results after post-CAIs in multiparous sows.

Seminal plasma (SP) proteins are responsible for sperm functional quality. Developing a reliable method to determine the degree of oxidative damage of these proteins is important for establishing semen fertilizing ability. The main aim of the study was to verify the applicability of protein carbonyl derivatives measurement in the SP of canine and stallion, using a method with 2,4-dinitrophenylhydrazine (DNPH). The research material consisted of ejaculates obtained from eight English Springer Spaniels, and from seven half-blood stallions during the breeding and non-breeding season. The content of carbonyl groups in the SP was measured on the basis of the reactions with DNPH. The following reagent variants were used to dissolve protein precipitates: Variant 1 (V1) – 6M Guanidine solution and Variant 2 (V2) – 0.1M NaOH solution. It has been shown that to obtain reliable results for the measurement of protein carbonylated groups in the dog and horse SP, both 6M Guanidine and 0.1M NaOH may be used. A correlation was also found between the number of carbonyl groups and the total protein content in the canine (V1: r = -0.724; V2: r = -0.847) and stallion (V1: r = -0.336; V2: r = -0.334) SP. Additionally, the study showed a higher content (p≤0.05) of protein carbonyl groups in the stallion SP in the non-breeding season compared to the breeding season. The method based on the reaction with DNPH, due to its simplicity and cost effectiveness, appears to be suitable for large-scale application in the determination of the SP proteins oxidative damage in dog and horse semen.