Seminal quality comparison of first and second cryopreserved ejaculates of Alpine kid goats by flow cytometry

Discarding the first ejaculate is recommended as an alternative for improving seminal quality after long sexual resting, especially when semen should be used for cryopreservation. However, when the males are not in sexual resting the necessity to discarding the first ejaculate is still unknown. Therefore, this study aimed to compare by flow cytometry the quality of the first and second ejaculates. Ten kids and uniform goats between 5 and 6 months of age were used in a completely randomized design. Semen collection was carried out every 4 days, until a total of five ejaculates per animal in each treatment was completed. The fresh and frozen semen collected were processed and analyzed using macroscopic and microscopic parameters, resistance test, hypo-osmotic medium test, and flow cytometry (FC). The FC parameters were production of reactive oxygen species, plasma and acrosomal membrane integrity, and lipid peroxidation of the plasma membrane. The ejaculates did not differ for the resistance test, the reactivity in the hypo-osmotic medium and for the macroscopic and microscopic seminal parameters, except for sperm volume and concentration. The first ejaculate had a higher percentage of minor and total defects. None of the FC parameters analyzed differed between the first and second ejaculates. The first and second ejaculates demonstrated similar seminal qualities, so for Alpine kid goats without a sexual resting period, discarding the first ejaculate it is not recommended.

Seminal and histopathological alterations in bucks challenged with Mannheimia haemolytica serotype a2 and its LPS endotoxin

Pneumonic mannheimiosis is a widespread respiratory bacterial disease of small ruminants caused by Mannheimia haemolytica serotype A2. The disease is known to affect the respiratory organs of infected animals, but its effect on other vital and reproductive organs has not been fully explored. Previous studies have demonstrated increased serum pro-inflammatory cytokine concentration post-challenge with M. haemolytica A2 and its LPS, indicating systemic inflammation in the host. This study determined the potential tissue changes and alterations of sperm parameters due to infection of M. haemolytica A2 and its LPS endotoxin. In this study, twelve experimental bucks were randomly assigned to three groups of four bucks each: group 1 (control group) were intranasally inoculated with 2 mL of PBS pH 7.0, group 2 received 2 mL of 1.2 × 10⁹ CFU/mL M. haemolytica A2 intranasally, and group 3 received 2 mL of LPS extracted from 1.2 × 10⁹ CFU/mL of M. haemolytica A2 intravenously. Semen samples were collected at pre-determined intervals using an electro-ejaculator and analysed immediately after collection. All experimental bucks were slaughtered via exsanguination on day 60 to collect their vital and reproductive organs at necropsy, and the samples were processed and analysed for histopathological changes. The current study has revealed that bucks challenged with M. haemolytica A2 and its LPS exhibited alterations in semen parameters such as motility, wave pattern, viability, and morphological abnormalities. Mild to moderate histopathological changes of the lung, liver, testis, epididymis, vas deferens, prostate, and lymph nodes were also observed in both challenged groups. Therefore, this study revealed the potential harmful effects of respiratory mannheimiosis on the reproductive organs of the infected bucks and sheds light on the expanse of systemic effects of this disease.

Relationships between age, body measurements, and testicular measurements in Arabia bucks in Algeria

Body size and testicular measurements were found to be important parameters for the evaluation of the breeding quality. A study was therefore carried out on Arabia bucks (n = 180) to record normal testicular characteristics and to evaluate the effect of age on body (BCS, BW, WH, CG, AC, CS, and BL) and testicular (SC, TW, EW, TL, TD, and TL) measurements. Animals were classified into three age classes (less than or equal to 12 months, from 12 to 24 months, and over 24 months). The BW, BCS, testicular, and body measurements of the 3rd age group were significantly higher than those of age groups 1 and 2 (p < 0.01). Male age had a significant effect (p < 0.01) on BW, BCS, and body measurements. Indeed, the parameters of the 3rd age group were significantly higher than those of the 1st and 2nd age groups (p < 0.01). The same was true for testicular measurements (SC, TL, TW, EW, and EL) except for testicular diameter (TD) where the results of the first two age groups had no significant difference. The highest correlation coefficients were recorded between BW and all body (r = 0.7-0.9) and testicular traits (r = 0.72-0.85), BCS and body measurements (r = 0.73-0.89), and scrotal circumference and testicular measurements (r = 0.77-0.85). In conclusion, it was found that the use of BCS is readily measurable in live animals and is expected to be the best indicator of testicular and epididymal measurements. These results, particularly the predictive models developed, could be useful in the selection of males for reproduction.

Responses of testosterone hormone concentration, semen quality, and its related pro-inflammatory cytokines in bucks following Corynebacterium pseudotuberculosis and its mycolic acid infection

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis, a debilitating chronic disease of sheep and goats. Little is known about the buck's reproductive pathophysiology with respect to inoculation with Corynebacterium pseudotuberculois and its immunogen mycolic acid extract. Therefore, this present study was designed to determine the concentration of testosterone hormone, pro-inflammatory cytokines, and semen quality of the experimental animals. A total of 12 bucks, divided into groups 1, 2, and 3 (Negative control group, Positive control group and Mycolic acid group respectively), were enrolled in this study. Following inoculation, all goats were observed for clinical responses and monitored for 60 days post-challenge and were then sacrificed. Blood samples were collected via the jugular once before inoculation and on a weekly basis post-challenge. Semen samples were collected 2 weeks post-challenge and prior to the sacrifice of the experimental animals. During the post inoculation period of 60 days, the concentration of testosterone hormone for group 2 was increased significantly (p < 0.05) in weeks 5, 6, and 9 but decreased in weeks 2 and 7 post inoculation. In group 3, the mean concentration of testosterone was increased significantly (p < 0.05) in weeks 5, 6, 7, and 9 post inoculation but decreased in week 2. The concentration of interleukin 6 (IL 6) in treated group 2 did not show any significant difference (p > 0.05) but increased significantly (p < 0.05) in week 2 post inoculation in group 3. For concentration of interleukin 1β (IL1β) in both treated groups 2 and 3 showed significant difference (p < 0.05) in weeks 2 and 3 post inoculation. The tumor necrosis factor-alpha (TNF-α) concentration in both treated groups 2 and 3 did not show any significant difference (p > 0.05) as compared to group 1. The concentration of interferon-γ (IFNγ) significantly increased (p < 0.05) for group 2 for weeks 2, 3, 4, and 5 where else for group 3 was not in significant difference (p > 0.05) compared to group 1. Both group 2 and group 3 showed a reduction in semen qualities as compared to group 1, but the severity was more intense in group 2 if compared to group 3. In conclusion, therefore, the present study concluded that the mycolic acid group revealed significant responses of testosterone hormone concentration, semen quality, and its related pro-inflammatory cytokines in bucks following infection but the severity lesser compared to Corynebacterium pseudotuberculosis group.

Sperm parameters and biochemical components of goat seminal plasma in the rainy and dry seasons in the Brazilian Northeast: the season's influence on the cooling of semen

The present study aimed to verify the caprine semen characteristics during dry and rainy seasons in the Brazilian Northeast, and the influence of these seasons on cooled semen. Seminal volume, concentration, percentage of motile cells, vigor and spermatic morphology, as well as biochemical profile (fructose, citric acid, P, Ca2+, Mg, total proteins and phospholipase A2 activity) were analyzed. It was observed a reduction (P<0.05) in normal sperm morphology, fructose, citric acid, P, Mg and total protein concentration during the dry season, which did not affect the motility, vigor, volume and sperm concentration. Phospholipase A2 activity was increased during the dry season (P<0.05). The analysis of the semen cooled at 4ºC during 48 hours showed reduction in total motility and vigor sperm during the dry season (P<0.05). Based on these results, we conclude that the best period of year for caprine semen cooling is the rainy season.

Effect of antioxidants on post thaw microscopic, oxidative stress parameter and fertility of Boer goat spermatozoa in Tris egg yolk glycerol extender

This study was conducted to determine the effect of antioxidants on standard semen parameters, lipid peroxidation and fertility of Boer goat semen after cryopreservation. Ejaculates from four bucks were collected, evaluated and pooled at 37°C. The pooled semen was diluted with Tris citric acid fructose for washing. Semen samples, which were diluted with a Tris-based extender containing the antioxidant ascorbic acid (8.5mg/ml), butylated hydroxytoluene (2mM), cysteine (5mM) and hypotaurine (10mM) and an extender without antioxidant supplementation were cooled to 4°C and frozen in 0.25 straws with programmable freezer and finally stored in liquid nitrogen. Data (10 replicates) were analyzed by one-way analysis of variance. Mean (±SEM) progressive motility was significantly higher in ascorbic acid than other supplement groups and control samples (P>0.05). Best values were observed in ascorbic acid followed by BHT, cysteine, and hypotaurine. Antioxidant supplementation in extender showed significant (P<0.05) better values than the control group for sperm membrane integrity, acrosome integrity and viability. The ability of antioxidants to reduce the lipid peroxidation (LPO) after freeze thawing was measured by the formation of malondialdehyde (MDA) using the thiobarbituric acid method. Results showed that addition of antioxidants significantly reduced the rate of LPO in comparison to control (P<0.05). Ascorbic acid exhibited better values (1.27±0.28), than butylated hydroxytoluene, cysteine and hypotaurine 1.32±0.42, 2.27±0.16 and 2.38±0.17 respectively, which are significantly better than control (3.52±0.54). Higher pregnancy rate was observed with ascorbic acid followed by butylated hydroxtolune, hypotaurine and cysteine. However, differences in the fertility rate were non-significant with hypotaurine, cysteine and control groups.

Artificial insemination of small ruminants - a review

Artificial insemination (AI) can undoubtedly be regarded as the oldest and most widely used assisted reproductive technique/technology (ART) applied in livestock production and it is one of the most important ARTs. The three cornerstones of its application are that it is simple, economical and successful. Artificial insemination offers many well-known benefits for producers. Fresh, fresh + diluted + chilled and frozen semen can be used for AI in small ruminants. To ensure its successful use, the AI technique must be selected on the basis of the type of semen planned to be used. This review paper gives a detailed overview of semen processing and its effects on semen quality, as well as of the AI techniques applied in small ruminants and their success rates.

Effects of Exogenous Glutathione on the Quality of Chilled Bull Semen

Glutathione (GSH) at concentrations of 0.0 (control), 0.5, 1.0, 2.0 and 3.0 mM was added to chilled bull semen to determine its effects on the keeping quality of semen used for artificial insemination (AI). The semen was preserved with egg yolk citrate extender. All samples were stored at 4-8 degrees C for 5 days. Sperm motility and proportion of abnormal acrosome were assessed daily. Sperm motility was significantly (p < 0.01) higher in the semen treated with 0.5 mM glutathione than in untreated semen on each day. The optimum sperm motility (>or=50%) for AI was retained significantly (p < 0.01) for 3 days in 0.0, 0.5, 1.0 and 2.0 mM glutathione treated semen, whereas in 0.3 mM glutathione-treated semen, sperm motility was 46.8% for 3 days. Acrosomal damage was significantly (p < 0.01) reduced after addition of 0.5 mM GSH in the preserved semen. Bull semen can be preserved in chilled condition for 5 days with 0.5 mM GSH with sperm motility above 40% and 12% acrosome abnormality.

Reproductive characteristics of Rayini male goats of Kerman province in Iran

An artificial vagina was used to collect semen from 14 native Iranian Rayini goats, at 15-day intervals starting on 1 July and ending on 30 December 2000. Testicular size, semen volume, sperm concentration, percent live sperm, percent normal sperm, and total number of live-normal sperm were significantly higher during the summer months. The average semen volume, percent live sperm and percent abnormal sperm during the sampling period varied between 1 and 1.4 mL, 60 and 78%, and 7 and 13%, respectively. The total number of live and normal sperm in the ejaculate during the sampling period varied from 1000 to 2500 million. Testicular size, semen volume and the total number of live and normal sperm were significantly greater in bucks weighing 55-60 kg as compared with 50-54 kg. Seminal fluid pH values were significantly lower from July to October (pH <6) than the values from November to December (pH >6.1). Lowest level of lactate dehydrogenase in the seminal fluid was recorded in early September (2.2 U/mL) and the highest level in November (2.5 U/mL). Seminal fluid K ion level increased gradually from July (52 mg/dL) to the November (97 mg/dL). Variation of seminal fluid Na ion concentration (71-74 mg/dL) was not significant during the sampling period. The correlation coefficients of total number of live-normal sperm with seminal fluid K level (r=-0.65) and LDH (r=-0.36) were negative (P<0.01). The data indicated that the semen quality and quantity of Rayini bucks were higher during summer and early autumn.