Low concentrations of soybean lecithin nanoparticles had a positive impact on Holstein bulls' cryopreserved semen.

Spermatozoa can experience negative changes when subjected to freezing and thawing, including lowered motility, viability and acrosome response. Herein, the effects of different concentrations of soybean lecithin nanoparticles on cryopreserved Holstein bull semen were examined. Semen was collected, cryopreserved and utilized for sperm kinetic parameter analysis following dilution, equilibration and thawing with 0.5% soybean lecithin (E1), the control extender, and 0.75% (E2), 0.5% (E3), 0.25% (E4) and 0.125% (E5) of lecithin nanoparticles. Results revealed that following dilution, the progressive motility (PM) at E3, E4 and E5 of lecithin nanoparticles was higher (p < .05) than it was for E2. After equilibration, compared to the E1, E2, and E3 values, the PM, vitality, normal morphology, membrane integrity and intact acrosome values at the E5 were consistently greater (p < .05). Comparing the percentages of intact acrosome and membrane integrity at E2 and E3 to E4 and E5, a substantial decrease (p < .05) was seen. Following thawing, the percentage of PM improved at E2 and E5, even though their mean PM values were similar (p > .05) compared to E1, E3 and E4. Vigour and progression parameters of sperm (DAP, DCL, DSL, VAP, VCL, VSL and STR) at E5 were higher (p < .05) than those at E1, E2, E3 and E4. In conclusion, the cryopreserved sperm from Holstein bulls revealed outstanding properties both after equilibration and after thawing with 0.125% lecithin nanoparticles, and they were sensitive to high dosages.

Molecular and physiochemical evaluation of buck semen cryopreserved with antioxidants.

The current study evaluated the physiochemical quality and gene expression profile of post-thawed buck semen after supplementation with antioxidants [melatonin (M), L-carnitine (LC), cysteine (Cys), LC + M, M + Cys, LC + Cys, LC + Cys + M] in comparison with the non-treated control group. Physical and biochemical characteristics of semen were evaluated following freezing and thawing. Transcript abundance of six selected candidate genes was profile using quantitative real-time PCR. The data demonstrated significant enhancement of post-freezing total motility, progressive motility, percentage of live sperm, CASA parameters, plasma membrane and acrosome integrity in all groups supplemented with Cys, LC, M + Cys and LC + Cys compared with the control group. The biochemical analysis of semen indicated that semen groups supplemented with LC and LC + Cys recorded increased levels of GPX and SOD that were coupled with up-regulation of antioxidant genes (SOD1, GPX1 and NRF2) and mitochondrial transcripts (CPT2 and ATP5F1A). Moreover, H2O2 level and DNA fragmentation percentage were reduced compared with other groups. In conclusion, supplementation of Cys alone or in combination with LC positively improved the post-thaw physiochemical properties of rabbit semen through activation of bioenergetics-related mitochondrial genes and cellular antioxidant defence mechanism.

Adaptive and Biological Responses of Buffalo Granulosa Cells Exposed to Heat Stress under In Vitro Condition.

The steroidogenesis capacity and adaptive response of follicular granulosa cells (GCs) to heat stress were assessed together with the underlying regulating molecular mechanisms in Egyptian buffalo. In vitro cultured GCs were exposed to heat stress treatments at 39.5, 40.5, or 41.5 °C for the final 24 h of the culture period (7 days), while the control group was kept under normal conditions (37 °C). Comparable viability was observed between the control and heat-treated GCs at 39.5 and 40.5 °C. A higher release of E2, P4 and IGF-1 was observed in the 40.5 °C group compared with the 39.5 or 41.5 °C groups. The total antioxidant capacity was higher in response to heat stress at 39.5 °C. At 40.5 °C, a significant upregulation pattern was found in the expression of the stress resistance transcripts (SOD2 and NFE2L2) and of CPT2. The relative abundance of ATP5F1A was significantly downregulated for all heat-treated groups compared to the control, while TNFα was downregulated in GCs at 39.5 °C. Expression analyses of stress-related miRNAs (miR-1246, miR-181a and miR-27b) exhibited a significant downregulation in the 40.5 °C group compared to the control, whereas miR-708 was upregulated in the 39.5 and 40.5 °C groups. In conclusion, buffalo GCs exhibited different adaptive responses, to the different heat stress conditions. The integration mechanism between the molecular and secretory actions of the GCs cultured at 40.5 °C might provide possible insights into the biological mechanism through which buffalo GCs react to heat stress.

Physiological and molecular aspects of heat-treated cultured granulosa cells of Egyptian buffalo (Bubalus bubalis).

The physiological and molecular responses of granulosa cells (GCs) from buffalo follicles were investigated when there were in vitro heat stress conditions imposed. The cultured GCs were heat-treated at 40.5 °C for 24, 48 or 72 h while GCs of the control group were not heat-treated (37 °C). There were no differences in viability between control and heat-treated groups. There was an upward trend in increase in E2 secretion as the duration of heat stress advanced, being greater (P ≤ 0.05) for the GCs on which heat stress was imposed for 72 as compared with 24 h. In contrast, P4 release was less (P ≤ 0.05) from GCs heat-treated for 48 h than those cultured for 24 h and GCs of the control group. The relative abundance of ATP5F1A and SOD2 mRNA transcripts was consistent throughout the period when there was imposing of heat stress to sustain mitochondrial function. The relative abundance of CPT2 transcript was less in heat-treated GCs than in GCs of the control group. There was a greater relative abundance of SREBP1 and TNF-α mRNA transcripts after 48 h of heat-treatment of GCs than GCs of the control group. In conclusion, the results from the current study indicate buffalo GCs cultured when there was imposing of heat stress maintained normal viability, steroidogenesis and transcriptional profile. The stability of antioxidant status and increased transcription of genes regulating cholesterol biosynthesis and stress resistance may be defense mechanisms of buffalo GCs against heat stress.

Subclinical endometritis and postpartum ovarian resumption in respect to TNF-α, IL-8 and CRP in Egyptian buffaloes.

The study was carried out to find the relation between subclinical endometritis (SCE) and postpartum (pp.) ovarian resumption as well as to evaluate serum and endometrial TNF-α, IL-8 and serum CRP in buffaloes with and without SCE. Thirty-nine pluriparous buffaloes at the 3rd (W3), 5th (W5) and 7th (W7) week pp. were involved in this experiment. The parity of the buffaloes ranged from 4 to 8 with an average 5.8±0.2. Subclinical endometritis was diagnosed by the percentage of polymorphonuclear cells (PMNs) in uterine cytology obtained from endometrial cytobrush at W5 and W7. The cut-off point of PMNs% in buffaloes for SCE was ≥ 6% at W5 or ≥ 4% at W7. According to PMNs%, buffaloes were divided into SCE group (n=27) and non-SCE group (n=12). Ovarian cyclicity was monitored by rectal palpation, ultrasonography and progesterone assay at W3, W5 and W7. Serum and endometrial TNF-α, IL-8 and serum CRP were estimated at W5 and W7. Buffaloes with SCE (55.6%) showed delayed ovarian activity as compared to non-SCE (16.7%) animals (P=0.036). Significant increase in serum cytokines and CRP levels were detected at W5 (P ˂0.05) and W7 (P <0.01) in SCE buffaloes as compared to non-SCE. Endometrial levels of cytokines were significantly (P ˂0.05) elevated in SCE buffaloes. Serum and endometrial cytokines showed significant positive correlation. Furthermore, levels of TNF-α, IL-8 and CRP exhibited significant positive correlation with PMNs%. In conclusion, SCE delayed postpartum ovarian cyclicity in buffaloes. Moreover, TNF-α, IL-8 and CRP assessments could be efficient tools in prediction of SCE in buffaloes.