Association between body condition score, testicular haemodynamics and echogenicity, nitric oxide levels, and total antioxidant capacity in rams.

Higher body fatness adversely affects metabolic and hormonal homeostasis. The present work aimed to evaluate the association between body condition score (BCS) and haemodynamic pattern and echogenic appearence of the testes as well as nitric oxide (NO) levels and total antioxidant capacity (TAC). For that, fifteen Ossimi rams were blocked according to their BCS into a lower BCS group (L-BCS:2-2.5; n = 5), medium BCS group (M-BCS:3-3.5; n = 5), and higher BCS group (H-BCS:4-4.5; n = 5). Rams were examined for testicular haemodynamics (TH; Doppler ultrasonography), testicular echotexture (TE; B-mode image software analysis), and serum levels of NO and TAC (colorimetric). Results are presented as means ± standard error of the mean. There was a significant (P < 0.05) difference in the resistive index and pulsatility index means among the groups under experimentation, being the least in the L-BCS group (0.43 ± 0.02 and 0.57 ± 0.04, respectively) compared to the M-BCS (0.53 ± 0.03 and 0.77 ± 0.03, respectively) and H-BCS rams (0.57 ± 0.01 and 0.86 ± 0.03, respectively). Among blood flow velocity measurements [peak systolic, end-diastolic (EDV), and time-average maximum], only EDV showed significant (P < 0.05) higher values in the L-BCS group (17.06 ± 1.03 cm/s) compared to M-BCS (12.58 ± 0.67 cm/s) and H-BCS (12.51 ± 0.61 cm/s) groups. Regarding the TE results, there were no significant differences among the examined groups. There were significant differences (P < 0.01) in the concentrations of TAC and NO among the groups under experimentation, in which the L-BCS rams had the highest levels of TAC and NO in their sera (0.90 ± 0.05 mM/L and 62.06 ± 2.72 µM/L, respectively) than the M-BCS (0.058 ± 0.05 mM/L and 47.89 ± 1.49 µM/L, respectively) and H-BCS rams (0.45 ± 0.03 mM/L and 49.93 ± 3.63 µM/L, respectively). In conclusion, body condition score is associated with both testicular hemodynamic and the antioxidant capacity in rams.

Influences of glycine supplementation during vitrification on the developmental potential of vitrified/warmed immature dromedary camel oocytes.

Oocytes experience detrimental osmotic stress during vitrification and warming procedures because of the osmolality imbalance between the vitrification-warming fluids and the intracellular environment. Cellular osmotic homeostasis can be preserved by glycine, a powerful osmolyte with antioxidant properties. We aimed to examine the influences of supplementing glycine to the vitrification solutions (VS) on the developmental potential of vitrified/warmed immature dromedary camel oocytes following IVM/IVF and in vitro embryo culture (IVC). Cumulus oocyte complexes (COCs) were collected from dromedary camel ovaries and randomly allocated into two groups namely control (oocytes subjected directly to IVM) and vitrified (COCs were vitrified into VS supplemented with 0.0, 0.5, 1.0 or 2.0 mM glycine). For vitrification, COCs were equilibrated for 3 min in 12.5% ethylene glycol; EG plus 12.5% dimethyl sulfoxide; DMS and then they were vitrified for 60 s in VS composed of 25% EG + 25% DMSO using solid surface vitrification (SSV). Warming of vitrified oocytes was conducted in decreasing concentrations of trehalose solution. Following vitrification and warming, the morphologically viable oocytes were subjected to IVM for 36 h. Matured oocytes were then fertilized in vitro by epididymal spermatozoa and cultured for seven days. The results showed that the percentage of viable oocytes assessed by trypan blue stain was significantly higher (p ≤ .05) in the 1.0 mM glycine-supplemented group than 0.0- and 2.0-mM glycine-supplemented ones (90.0 % vs. 80.0% and 76.6%, respectively). However, no significant difference was observed between 0.5 mM glycine and other vitrified groups. Nuclear maturation rates, cleavage (48-h post-insemination; pi) and blastocyst rate (7-days pi) were significantly lower in vitrified groups than control ones (p ≤ .05). Among vitrified groups, these parameters were the highest in the 1.0 mM glycine-supplemented group. Taken together, supplementation of vitrification solutions with 1.0 mM glycine could enhance the developmental potential of vitrified/warmed immature dromedary camel oocytes.

Intramuscular administration of l-arginine boosts testicular hemodynamics, plasma concentrations of testosterone and nitric oxide in heat-stressed rams.

The current study aimed to assess, for the first time, the effects of intramuscular injection of l-arginine (L-arg) on testicular hemodynamics, echogenicity, and plasma concentrations of testosterone, total antioxidant capacity, and nitric oxide (NO) in Ossimi rams. Twelve sexually matured heat-stressed rams were randomly assigned to one of two groups: the L-arg group (n = 6) received 5 mg/kg L-arg dissolved in 2 ml normal saline 0.9%, or the control group (n = 6) received merely 2 ml of normal saline 0.9%. Blood sampling, B-mode ultrasound assessment of the testicular parenchyma, and pulsed-wave Doppler ultrasound of the testicular artery for both right and left testis were performed immediately before 0 min and 1, 4, 24, 48, 72, and 168 h after L-arg or saline administration. In the L-arg group, resistive index (RI) and pulsatility index (PI) means were significantly lower compared to the control group at 4-168 h post-treatment. Plasma testosterone concentrations were higher (P < 0.05) at 4 h and onward in the L-arg treated compared to the control rams, the same for NO levels however its increase (P < 0.05) was observed as soon as 1 h post-treatment. In L-arg treated rams, NO concentrations were positively correlated to plasma testosterone concentrations (r = 0.7, p < .01), but negatively correlated to both RI and PI (r = -0.8 and -0.6, respectively, p < .01). In conclusion, l-arginine administration enhanced testicular blood flow and increased plasma testosterone and nitric oxide concentrations in heat-stressed rams.

Exogenous L-arginine administration improves uterine vascular perfusion, uteroplacental thickness, steroid concentrations and nitric oxide levels in pregnant buffaloes under subtropical conditions.

Heat stress (HS) during pregnancy adversely affects uterine vascular perfusion and foetal development. L-arginine (L-Arg), a nitric oxide (NO) precursor, has been proven to enhance an organ's vascular perfusion. Therefore, this study aimed to examine the effect of L-Arg administration on the pregnant buffaloes' uterine haemodynamics and uteroplacental thickness under environmental HS conditions. For this purpose, pluriparous (n = 12) HS-pregnant buffaloes (mid-gestation, 180-190 days; temperature humidity index >85) were haphazardly assigned into two groups, either administered a single intravenous (IV) bolus of 5 mg/kg BW of L-Arg Hcl (n = 6; ARG) or received normal saline (0.9%; IV; 25 ml) that served as a control group (n = 6; CON). Combined uteroplacental thickness (CUPT, mm), middle uterine arteries' (MUA) diameter (mm) and uterine Doppler haemodynamics (ipsilateral and contralateral to the pregnant horn) were examined utilizing B-mode and colour Doppler ultrasonography, respectively. The serum levels of progesterone (P4), estradiol 17ß (E2), nitric oxide (NO) and total antioxidant capacity (TAC) were assayed using commercial kits. The experimental time points were - 1, 0, 2, 4, 24, 48, 72, 96 and 120 h post-L-Arg administration. The ARG group showed higher (p < .05) CUPT and MUA diameter values starting at 24 h post-treatment and onward than the control buffalo cows. In addition, there were improvements (p < .05) in the blood flow parameters in the ipsilateral MUA after L-Arg treatment evidenced by lower values of pulsatility and resistive indices starting at 48 and 4 h, respectively and onward, and higher values of peak systolic velocity, coloured areas towards the pregnant uterine horn (both 24-72 h). Increases in the NO levels were found during the period between 4 and 120 h in the ARG group compared to the CON group. Moreover, significant increases in the E2 and P4 means were noted in the ARG group, especially at 24 h onward, respectively compared to the CON group. Concerning the TAC status, neither the administration nor the hours affected serum TAC levels in the HS pregnant buffaloes (CON and ARG). In conclusion, L-Arg administration improved uteroplacental thickness and enhanced uterine haemodynamics, NO levels, and steroids production in mid-pregnant buffalo cows under environmental heat stress conditions which could improve foetal growth and development.

Exogenous L-carnitine Administration Ameliorates the Adverse Effects of Heat Stress on Testicular Hemodynamics, Echotexture, and Total Antioxidant Capacity in Rams.

Heat stress (HS) diminishes the testicular antioxidant defense systems, which adversely affect the testicular blood perfusion. Improving the testicular hemodynamics during HS conditions is of a great impact on the whole reproductive performance in rams. This study aimed to evaluate the ameliorative effects of L-carnitine (LC) on the testicular blood flow and echotextures and also on the total antioxidants (TAC) and nitric oxide (NO) concentrations in the serum during HS conditions in rams. Testicular blood flow was evaluated through scanning of the supra-testicular artery (STA) spectral patterns through pulsed Doppler ultrasonography [peak systolic velocity (PSV), end-diastolic velocity (EDV), time average maximum velocity (TAMAX), resistive index (RI), and pulsatility index (PI)], while the echotexture assessment of testicular parenchyma was performed by a computerized software program. Moreover, TAC and NO concentrations were assayed colorimetrically using the spectrophotometer. There were significant decreases (P < 0.05) in values of PSV at 48 and 168 h (23.45 ± 0.39 and 23.37 ± 1.41 cm/s, respectively), and TAMAX at 1, 48, and 168 h (17.65 ± 0.95, 17.5 ± 0.13, and 16.9 ± 1.05 cm/s, respectively) after LC administration compared to just before administration (31.92 ± 1.13 and 21.58 ± 0.92 cm/s, respectively). Values of RI and PI of the examined STA significantly decreased, especially at 1 h for RI (0.45 ± 0.02) and 1 and 48 h for PI (0.66 ± 0.06 and 0.65 ± 0.05, respectively) after LC treatment to 0 h (0.55 ± 0.03 and 0.84 ± 0.06, respectively). The EDV values did not show any significant (P < 0.05) changes in all the experimental time points. There were significant (P < 0.05) increases in the values of pixel intensity of the testicular parenchyma, especially at 1 and 168 h (78.71 ± 2.50 and 88.56 ± 4.10, respectively) after LC administration, compared to just before administration (69.40 ± 4.75). Serum NO levels tend to increase after LC administration (P = 0.07) concerning just before administration. While TAC values showed significant gradual increase and reached the highest values at 168 h (2.75 ± 0.58 mM/l) after LC administration, compared to 0 h (1.12 ± 0.05 mM/l). In conclusion, exogenous LC administration ameliorates testicular hemodynamic disruptions, as measured by spectral Doppler ultrasonography, via augmentation of the rams' total antioxidant capacity under HS conditions.

Exogenous oxytocin administration improves the testicular blood flow in rams.

The current research aimed to examine the effects of single-dose oxytocin administration on testicular blood flow measurements peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI) and pulsatility index (PI) and plasma steroid (testosterone and oestradiol-17ß) concentrations in rams. In the treated group, eight mature Ossimi rams during the breeding season were injected intravenously (iv) with 20 IU oxytocin, while the other eight male rams were administered normal saline (2 ml) iv as a control group. Venous blood samples and testicular blood flow in the left and right testes were examined immediately before (0) and 5, 30, 60 and 120 min after injections. The control group did not show significant changes in the variables examined (p > .05), except for the EDV (p < .05). In the treated group, the administration of oxytocin led to a significant decrease in RI and PI values starting 5 min after oxytocin administration until 60 min after its application (p < .05). The plasma concentrations of testosterone and oestradiol-17ß raised from 5 to 30 min after oxytocin injection (p > .05) and then declined significantly until 120 min (p < .05). In conclusion, oxytocin is a potent testicular vasodilator affecting the testicular vascular tone and steroid concentrations in rams.

Effect of different vitrification solutions and cryodevices on viability and subsequent development of buffalo oocytes vitrified at the germinal vesicle (GV) stage.

The cryopreservation of immature oocytes would generate a readily available, non-seasonal source of female gametes for research and reproduction. In domestic animals, the most promising results on oocyte cryopreservation have been reported in cattle, few studies have been conducted on buffalo. The aim of the present study was to compare the use of different vitrification solutions and various cryodevices on viability and developmental competence of buffalo oocytes vitrified at the germinal vesicle (GV) stage. Cumulus oocyte-complexes (COCs) obtained at slaughterhouse from mature buffalo ovaries were randomly divided into three main groups and vitrified by using either straw or open pulled-straw (OPS) or solid surface vitrification (SSV) in a solution composed of either 20% ethylene glycol (EG) + 20% glycerol (GLY); VS1 or 20% EG + 20% dimethylsulfoxide (DMSO); VS2, respectively. Following vitrification and warming, viable COCs were matured in vitro for 22 h. Some COCs were denuded and stained with 1.0% aceto-orcein to evaluate nuclear maturation, whereas the others were fertilized and cultured in vitro for 7 days to determine the developmental competence. Although the recovery rate (64.9%) was the lowest in the oocytes vitrified by SSV using 20% EG + 20% DMSO as compared to the other groups, the best survival rate of the COCs was achieved in the same treatment (96.7%), which was significantly higher (P < 0.05) than those vitrified using traditional straws (71.8% in VS1 and 73.6% in VS2) or those vitrified using OPS and VS1 (73.9%). Furthermore, in the nuclear maturation test, the highest maturation rate (75.5%) was achieved in SSV vitrified COCs using 20% EG + 20% DMSO (VS2), which was similar to the controls (77.1%). Post IVF and embryo culture, the highest cleavage and blastocyst development rates were obtained in COCs vitrified in 20% EG + 20% DMSO using SSV (47.1% and 24.0%, respectively), which showed no difference from the controls (61.2% and 46.9%, respectively). Our results clearly show that the combination of SSV and 20% EG + 20% DMSO could be used effectively to vitrify GV stage buffalo COCs.