Number Of Insemination Doses Research Articles

Application of the microflow technique for the selection of stallion semen

Routine semen preparation techniques are not always satisfactory for all stallions. Some stallions, despite poor semen parameters, are valuable for breeders who want to produce equally worthwhile offspring. In recent years, advanced sperm selection methods such as the microflow technique have been developed and successfully applied to humans. The aim of this study was to adapt the microflow technique for selection of stallion semen, focusing on their predicted benefits for sperm quality. The experiment was performed with semen of 6 stallions, which after combining in equal volumes created pooled research sample. Semen was left for 24 h in order to reduce the viability and motility of spermatozoa and divided into 3 parts, the control and the two research groups separated using ZyMōt Devices with two different incubation times (30 and 45 minutes). For each group, the basic sperm characteristics were assessed by SCA/CASA system, and fragmentation was evaluated using the TUNEL technique. The Z-score test was used for statistical analysis. In the sample incubated for 30 min in ZyMōt Devices, sperm motility increased from 28% to 52.15% (p=0.001), including sperm with progressive motility which increased from 8.47% to 41.91% (p<0.00001). After extending the incubation time for 45 minutes, these parameters were even higher: motility 62.43% (p<0.00001), progressivemovement 55.33% (p<0.00001). It should be noted, however, that in the case of both research samples, the concentration of sperm decreased from 804.68 M/ml in the control to 32.35 M/ml (p<0.00001) after 30 min incubation and 40.37 M/ml after 45 min incubation, respectively (p<0.0001). Sperm selection did not affect vitality. The TUNEL technique showed a very low percentage of spermatozoa with apoptosis in the semen fraction after selection at both incubation times. In summary, the microflow technique is an effective method for selection of stallion sperm with high motility, progressive movement and low DNA sperm fragmentation, with unchanged vitality parameters. Comparing the two incubation times, it was found that extending the incubation time to 45 minutes improved sperm concentration and spermatozoa with progressive motility. Nevertheless, prolonged incubation caused an increase in apoptotic spermatozoa that penetrate through a membrane with microchannels. It should be considered that sperm selection by microflow technique drastically reduces sperm concentration, which in practice translates into a significant reduction in the number of insemination doses which will increase costs significantly. However, this method can be successfully used for sperm selection for the ICSI procedure.

Efficiency of Semen Cryopreservation in Stallions.

Simple SummaryThe quality of stallion semen after freezing and thawing differs among stallions, but it remains to be determined whether such differences are also affected by horse breed. In this study, semen quality was analysed retrospectively in 1012 frozen–thawed ejaculates from 134 stallions of 5 breeds. The percentage of ejaculates acceptable for artificial insemination (AI) and the number of insemination doses per ejaculate was then calculated. Sperm motility before freezing was the most important explanatory variable for the percentage of ejaculates with a post-thaw quality acceptable for AI. Of the other variables studied, stallion age was the most important parameter and a decrease in the percentage of acceptable ejaculates was evident in stallions older than 9 years. There were also more acceptable frozen–thawed ejaculates in Arab stallions compared to Warmbloods, Quarter Horses and Icelandic horses. The analysis thus demonstrates differences in the percentage of acceptable cryopreserved ejaculates among breeds. Total sperm count was the most important variable determining the number of semen doses obtained per acceptable frozen–thawed ejaculate. Differences in the cryotolerance of spermatozoa exist among stallions, but it remains to be determined to what extent such differences are affected by breed. In this study, post-thaw semen quality in stallions presented for semen cryopreservation was analysed retrospectively (1012 ejaculates from 134 stallions of 5 breeds). The percentage of frozen–thawed ejaculates acceptable for artificial insemination (AI) and the number of insemination doses per cryopreserved ejaculate was calculated. Logistic regression analysis revealed sperm motility in raw semen as the most important explanatory variable for the percentage of cryopreserved ejaculates with a post-thaw quality acceptable for AI. Of the other variables included into the model, stallion age was the most important parameter with more acceptable ejaculates in younger than in older stallions. Logistic regression also showed more acceptable frozen–thawed ejaculates in Arab stallions versus Warmbloods, Quarter Horses and Icelandic horses. The analysis thus demonstrates differences in the percentage of acceptable cryopreserved ejaculates among horse breeds. Season was a less relevant explanatory variable for percentage of acceptable cryopreserved ejaculates. Logistic regression revealed total sperm count as the most important variable determining the number of cryopreserved semen doses obtained per acceptable ejaculate. In conclusion, logistic regression analysis revealed stallion age and breed as explanatory variables for the percentage of cryopreserved ejaculates acceptable for AI.

The dependence of the growth rate and meat content of young boars on semen parameters and conception rate

Boars have a decisive impact on the progress in pig production, however, there is no recent information about the optimal growth parameters during the rearing period for modern breed later used in artificial insemination (AI) stations. Therefore, the objective of the research was to conduct semen parameter and conception rate analyses on the basis of growth rate and meat content assessments made during the rearing of AI boars of different genotypes. The study was carried out between 2010 and 2014 and included 184 boars in five breed combinations: 46 Polish Large White, 50 Polish Landrace, 27 Pietrain, 36 Duroc×Pietrain and 25 Hampshire×Pietrain. Boars were qualified by daily gains and meat content assessment (between 170 and 210 days of life). A total number of 38 272 ejaculates were examined (semen volume (ml), spermatozoa concentration (×106 ml−1), total number of spermatozoa (×109) and number of insemination doses from one ejaculate (n)). The fertility was determined by the conception rate (%). Semen volume, spermatozoa concentration and conception rate (P<0.01), followed by the total number of spermatozoa and insemination doses (P<0.05) were characterized by the highest variability in relation to breed of boars. The effect of daily gains was reported for spermatozoa concentration, number of insemination doses, conception rate (all P<0.01) and total number of spermatozoa (P<0.05). The peak of growth for spermatozoa concentration, total number of spermatozoa, insemination doses and conception rate was achieved for 800 to 850 g gains. Meat content affected semen volume, number of insemination doses and conception rate (P<0.05). Rearing boars while maintaining daily gains at the 800 to 850 g level and 62.5% to 65% meat content helps AI stations to increase the efficiency and economic profitability, and the number of insemination doses to increase by up to 300 doses/boar within a year. The analyses of growth parameters may help increase the efficiency and economic viability of AI stations.

Effects of season on semen parameters and relationships between selected semen characteristics in Hypor boars

The aim of this study was to evaluate the effect of the season of the year on the quality of Hypor boar semen and to determine the correlations between selected semen characteristics in particular seasons. Ejaculates from Hypor boars were analyzed for volume, sperm concentration, percentage of spermatozoa with normal motility, total number of spermatozoa, and the number of insemination doses per ejaculate. Microscopic slides were prepared from semen samples. Each sample was evaluated for the morphology of spermatozoa. Spermatozoa with normal morphology were counted, as well as those with both major and minor abnormalities. Spermatozoa were measured for morphometric traits. Ejaculates were grouped by the season of collection: winter, spring, summer, and autumn. Correlation coefficients were calculated between sperm morphometric traits and the concentration and total count of spermatozoa in ejaculates. In spring and winter, sperm concentrations are higher compared to ejaculates collected in summer and autumn. In spring and summer, ejaculates contain spermatozoa of greatest motility. In spring, sperm cells have largest head dimensions. In autumn, spermatozoa are smallest in terms of dimensions. Significant correlations were observed between sperm concentration and total number of sperm in ejaculates vs. morphometric dimensions of sperm heads in Hypor boars' semen in the autumn, winter, and summer.

Influence of Collection Frequency on the Quality of Ejaculates from Large White and Pietrain Boars

Semen from Large White and Pietrain boars was collected at 3 and 4 day intervals. Volume, percentages of live, immature and motile spermatozoa and tail abnormalities were evaluated in order to assess ejaculate quality. The number of insemination doses per ejaculate was calculated for each breed and collection frequency. Reducing the interval between collections doesn’t modify ejaculate volume and spermatozoa motility but it increases the percentage of gametes that are immature or have an abnormal tail. A collection frequency of 3 days is better because the number of insemination doses per year is higher.

Does a Boar's Season of Birth Determine Semen Parameters and Reproductive Performance?

This article studies the effect of a boar's birth season and breed on semen parameters and its further reproductive performance. Research material consisted of 72 boars from three breeds (24 Polish Large White PLW, 24 Polish Landrace PL, 24 Duroc × Pietrain D × P). During the whole period of the study, selected semen parameters were analysed: semen volume, spermatozoa concentration, total number of spermatozoa, total number of motile spermatozoa, number of insemination doses and also reproductive indicators: farrowing rate, total born litter size, total number of piglets born live and still, and average piglet weight. Boars born in the winter and summer months demonstrated the highest spermatozoa concentrations (383.25 and 392.37 × 10(6)/ml), total number of spermatozoa (91.75 and 93.21 × 10(9)), total number of motile spermatozoa (76.10 and 77.99 × 10(9)) and number of insemination doses (24.53 and 24.89; p ≤ 0.01). Statistically lower values for these parameters were observed for boars born in the spring and especially in autumn (p ≤ 0.01). The significant impact of birth season on farrowing rate (p ≤ 0.05) and average piglet weight (p ≤ 0.05) was confirmed for PLW boars. For the PL breed, only the total number of piglets born live was proven to be significantly affected (p ≤ 0.05). No impact of birth season was shown on semen quality or reproductive performance for D × P boars. In our study, we showed that the birth season of a boar had a more impact on the level of semen parameters, and less on the reproductive performance indicators. The results indicated that both the quality of semen and reproductive performance varied in terms of the study factors, as well as between individual breeds of boars involved in the experiment.

CORRELAÇÃO DA MORFOLOGIA ESPERMÁTICA EM PROGRAMAS DE INSEMINAÇÃO ARTIFICIAL CONVENCIONAL EM NOVILHAS E VACAS DA RAÇA NELORE

The number of doses per pregnancy gives an indication of the fertility of the cow, the quality of semen and insemination. Therefore, the goal of this study was to investigate the relationship between the physical and morphological assessment of semen cryopreserved in Central with the number of doses per pregnancy and pregnancy rate by the number of doses used. Four Nelore bulls were challenged in 557 heifers and one bull in 156 Red Angus cows, both Nellore. For number of insemination doses required per pregnancy, tended to correlate significantly with lower amount of pathologies (0.053, P&gt; 0.05), with no significant correlation between sperm motility (0.433, P&gt; 0.05), spermatic vigor (0.932 , P&gt; 0.05), concentration (0.111, P&gt; 0.05), number of viable sperm (0.637, P&gt; 0.05), percentage of major diseases (1, P&gt; 0.05) and percentage of pathologies Total (0.623, P&gt; 0.05). For pregnancy rate, no significant correlation with sperm motility (0.218, P&gt; 0.05), spermatic vigor (0.252, P&gt; 0.05), sperm concentration (1, P&gt; 0.05), number of viable sperm (0.637, P&gt; 0.05), percentage of major diseases (0.395, P&gt; 0.05), percentage of pathologies smaller (0.740, P&gt; 0.05) and percentage of total conditions (0.872, P&gt; 0.05 ). For other parameters, there was a significant effect of sperm motility and (0.041, P &lt;0.05), and sperm motility and number of viable sperm (0.042, P &lt;0.05). The conclusion of this study that there was no significant correlation between the andrological examinationof post-thaw semen, number of insemination doses needed for pregnancy and pregnancy rate by the number of doses, with only significant correlation between sperm motility and vigor, and sperm motility and percentage of viable sperm

Influence of different centrifugation protocols on equine semen preservation

Three experiments were conducted to evaluate the impact of centrifugation on cooled and frozen preservation of equine semen. A standard centrifugation protocol (600 x g for 10 min=CP1) was compared to four protocols with increasing g-force and decreased time period (600 x g, 1200 x g, 1800 x g and 2400 x g for 5 min for CP2, 3, 4, and 5, respectively) and to an uncentrifuged negative control. In experiment 1, the influence of the different CPs on sperm loss was evaluated by calculating the total number of sperm cells in 90% of the supernatant. Moreover, the effect on semen quality following centrifugation was assessed by monitoring several sperm parameters (membrane integrity using SYBR14-PI, acrosomal status using PSA-FITC, percentage total motility (TM), percentage progressive motility (PM) and beat cross frequency (BCF) obtained with computer assisted sperm analysis (CASA)) immediately after centrifugation and daily during chilled storage for 3 d. The use of CP1 resulted in a sperm loss of 22%. Increasing the centrifugation force to 1800 x g and 2400 x g for 5 min led to significantly lower sperm losses (7.4% and 2.1%, respectively; P<0.05). Compared to the uncentrifuged samples, centrifugation of semen resulted in a better sperm quality after chilled storage. There were minimal differences between the CPs although total motility was lower for CP2 than for the other treatments (P<0.005). In experiment 2, the centrifuged samples were cryopreserved using a standard freezing protocol and analyzed immediately upon thawing. Samples centrifuged according to CP2 resulted in a higher BCF (P<0.005), whereas CP3 and CP5 yielded a lower BCF (P<0.05) when compared to CP1. There were no post thaw differences between CP1 and CP4. In experiment 3, DNA integrity of the different samples was analyzed using TUNEL. Although DNA integrity decreased over time, CP had no impact. In conclusion, the loss of sperm cells in the supernatant after centrifugation can be substantially reduced by increasing the g-force up to 1800 x g or 2400 x g for a shorter period of time (5 min) compared to the standard protocol without apparent changes in semen quality, resulting in a considerable increase in the number of insemination doses per ejaculate.

COMPARATIVE RESULTS OF CERTAIN QUANTITATIVE AND QUALITATIVE SEMEN PARAMETERSIN TZIGAI AND SUFFOLK RAMS

Volume, motility, concentration and sperm abnormalities represent important parameters within ram semen production examination from the viewpoint of quantitative and qualitative meaning. Without the sperm concentration analysis and without the establishment of live and viable sperm number there can’t be conceived a rational dilution so as to obtain a suitable number of insemination doses from each ejaculate and from each ram, in this way to realize a selection pressure through the agency of the sires (Fitzgerald and Stellflug, 1998). The crossing between Tzigai and Suffolk breeds is profitable thanks to high meat production and some superior quantitative and qualitative semen parameters that come the last one. The aim of the present study was to compare some semen parameters at these two breeds. Immediately after semen collection, there were exams a number of 8 semen samples from Tzigai rams and 16 samples from Suffolk rams, analyzing the sample volume, the sperm motility and concentration, the number of sperm/sample inclusive the sperm abnormalities. The differences between treatments were analyzed by ORIGIN7 and interpreted using the Student test. The medium value of the samples volume was by 0.43±0.01 ml at Tzigai rams and respectively 0.48±0.02 ml at Suffolk rams, of the sperm motility was by 0.93±0.01 decimal notes and respectively by 0.94±0.01, of sperm concentration was by 1.73±0.04 billions sperm/ml and respectively by 2.05±0.04 billions sperm/ml, of sperm number per sample was by 0.75±0.01 sperm/sample and respectively by 0.99±0.03 sperm/sample, of sperm head abnormalities was by 4.62±0.18% and respectively by 4.00±0.20%, of sperm intermediary piece abnormalities was by 5.25±0.31% and respectively by 4.31±0.11%, of sperm tail abnormalities was by 4.50±0.18% and respectively by 3.68±0.11% and of total sperm abnormalities was by 14.37±0.41% and respectively by 12.00±0.20%. Therefore were obtained non significant differences respect the samples volumes (t=1.58), the sperm motility (t=1.07) and the sperm head abnormalities (t=1.96), distinctly significant differences respect the sperm intermediary piece abnormalities (t=3.39) and the sperm tail abnormalities (t=3.77) and very significant differences respect the sperm concentrations (t=4.89), the sperm number per sample (t=4.67) and the total abnormalities (t=5.77). Results a superiority of Suffolk rams semen against the Tzigai rams semen respect the qualitative semen parameters.

Estimation of genetic parameters of semen characteristics and reproductive traits in AI boars

(Co)variance components and further genetic parameters of boar semen characteristics and reproductive traits were estimated using the REML procedure applied to multi-trait animal models. The calculations were based on data from 210,733 ejaculates stemming from 2862 AI boars and collected from 1990 to 1997 in insemination stations for boars in the Czech Republic. Equal model equations for all traits included the AI station and the breed or breed combination as fixed effects, the interval between two collections for the boar as covariable and the animal and residual effects as random effects. The following heritabilities were estimated: semen volume 0.58, sperm concentration 0.49, progressive motion of spermatozoa 0.38, abnormal spermatozoa 0.34, number of total spermatozoa 0.42, number of insemination doses 0.40, number of piglets born alive 0.08, total number of piglets born 0.05 and conception rate 0.29. Heritabilities and genetic correlations were estimated on average values for each boar.