Scrotal Surface Research Articles

Profiling the dynamic variations in body and scrotal surface temperatures of goats reared under stressful conditions using infrared thermography: Analytical perspectives

Infrared thermography (IRT) is an essential non-invasive method for analyzing surface temperature variations in animals, offering valuable insights into livestock stress responses. Despite their resilience, goats can face significant challenges under extreme conditions like heat-stress and water deprivation. This experiment aimed to delineate the dynamic variations in whole-body and scrotal surface temperatures in goats subjected to the combined impact of both conditions using IRT. Eight healthy Aardi bucks were exposed to three 72-h treatments: euhydration, dehydration, and rehydration. Continuous meteorological monitoring provided ambient-temperature, relative-humidity, and temperature-humidity index (THI) values. Surface temperatures were measured twice daily at 08:00 and 15:00, and thermal gradients between ambient and body or scrotal surface temperatures were computed. Based on the obtained mean THI values, the bucks experienced heat-stress throughout the experiment. Additionally, results revealed noticeable variations in both surface temperatures across treatments and time points, indicated by measures of central tendency, variability, shape descriptors, and frequency distribution of temperature. Morning measurements indicated lower temperatures and gradients under euhydration, while water deprivation led to higher temperatures and compromised thermal regulation. Conversely, afternoon data showed higher variability in temperature responses, highlighting the compounded effect of diurnal heat-stress and water deprivation. Although water-restoration mitigated some effects of deprivation, it did not fully restore thermal homeostasis to euhydrated levels. Thermal gradients further emphasized the goats' dynamic thermoregulatory mechanisms, which were compromised under water deprivation, particularly in the scrotal region, but were partially restored upon restoration. These findings demonstrate the effectiveness of IRT in assessing thermal responses in goats and underscore the importance of adequate hydration for maintaining thermal balance under heat-stress. The herein performed profiling provides valuable insights with implications for overall health, reproductive efficiency, productivity, and welfare in heat-stressed and water-deprived goats, which might offer a framework for future research on livestock adaptation to such challenging environmental conditions.

Effect of Age on Sexual Behaviour, Scrotal Circumference and Scrotal Surface Temperature in Sahiwal Bulls

Age of the bull influences the sexual behaviour and quality of semen. The present study was conducted to find out the age window at which the bull shows best reproductive performance. Fifteen Sahiwal bulls were selected and classified into three age groups (n=5, in each group) - G1(2- 3.5), G2 (>3.5-8) and G3 (>8-12) years. The sexual behaviour was recorded at the time of semen collection by CCTV camera at 15 days interval. Scrotal circumference (by scrotal tape) and scrotal surface temperature (by IRT) were also taken at monthly interval. The data so obtained in the experiment was subjected to statistical analysis by one-way analysis of variance (ANOVA) using SPSS software version 26.0 to draw scientific interferences. The results revealed that the mean value of scrotal circumference was significantly (p<0.05) low in G1 as compared to the other two groups. No significant difference was observed among the groups for scrotal surface temperature and scrotal temperature gradient. Most of the sexual behaviour parameters were significantly high in the G2 (>3.5-8) group except for the time to enter arena from preparation site and total number of mountings. Therefore, it can be concluded from this study that sexual behaviour is influenced by age and adult (middle) aged bulls performed better as compared to young and old groups.

Genome-wide 5′-C-phosphate-G-3′ methylation patterns reveal the effect of heat stress on the altered semen quality in Bubalus bubalis

Semen production and quality are closely correlated with different environmental factors in bovines, particularly for the buffalo (Bubalus bubalis) bulls reared under tropical and sub-tropical conditions. Factors including DNA methylation patterns, an intricate process in sperm cells, have an impact on the production of quality semen in buffalo bulls under abiotic stress conditions. The present study was conducted to identify DNA methylome signatures for semen quality in Murrah buffalo bulls, acclaimed as a major dairy breed globally, under summer heat stress. Based on semen quality parameters that significantly varied between the two groups over the seasons, the breeding bulls were classified into seasonally affected (SA = 6) and seasonally non-affected (SNA = 6) categories. DNA was isolated from purified sperm cells and sequenced using the RRBS (Reduced Representation Bisulfite Sequencing) technique for genome-wide methylome data generation. During the hot summer months, the physiological parameters such as scrotal surface temperature, rectal temperature, and respiration rate for both the SA and SNA bulls were significantly higher in the afternoon than in the morning. Whereas, the global CpG% of SA bulls was positively correlated with the afternoon's scrotal surface and rectal temperature. The RRBS results conveyed differentially methylated cytosines in the promoter region of the genes encoding the channels responsible for Ca2+ exchange, NPTN, Ca2+ activated chloride channels, ANO1, and a few structure-related units such as septins (SEPT4 and SEPT6), SPATA, etc. Additionally, the hypermethylated set of genes in SA was significantly enriched for pathways such as the FOXO signaling pathway and oocyte meiosis. The methylation patterns suggest promoter methylation in the genes regulating the sperm structure as well as surface transporters, which could contribute to the reduced semen quality in the Murrah buffalo bulls during the season-related heat stress.

Crafting Contours: A Comprehensive Guide to Scrotal Reconstruction.

This review delves into reconstructive methods for scrotal defects arising from conditions like Fournier's gangrene, cancer, trauma, or hidradenitis suppurativa. The unique anatomy of the scrotum, vital for thermoregulation and spermatogenic function, necessitates reconstruction with thin and pliable tissue. When the scrotal defect area is less than half the scrotal surface area, scrotal advancement flap can be performed. However, for larger defects, some type of transplantation surgery is required. Various options are explored, including testicular transposition, tissue expanders, split-thickness skin grafts, local flaps, and free flaps, each with merits and demerits based on factors like tissue availability, defect size, and patient specifics. Also, physicians should consider how testicular transposition, despite its simplicity, often yields unsatisfactory outcomes and impairs spermatogenesis. This review underscores the individuality of aesthetic standards for scrotal reconstruction, urging surgeons to tailor techniques to patient needs, health, and defect size. Detailed preoperative counseling is crucial to inform patients about outcomes and limitations. Ongoing research focuses on advancing techniques, not only anatomically but also in enhancing post-reconstruction quality of life, emphasizing the commitment to continuous improvement in scrotal reconstruction.

Impact of zinc, copper, manganese and chromium supplementation on growth performance and blood metabolic profile of Sahiwal (Bos indicus) male calves.

This study aimed to see the effect of oral supplementation of specific trace minerals mixture on the growth, immunity, and reproductive development of indigenous growing bull calves. Eighteen Sahiwal bull calves, with an average age of 6 months were chosen and divided into three groups. Group 1 was fed with a basal diet, Group 2 was provided with an additional specific trace mineral supplement to achieve a diet containing 70 ppm of Zn, 17.50 ppm of Cu, 65 ppm of Mn, and 1.75 ppm of Cr. Group 3 received a 25% extra supplement to achieve a diet containing 87.50 ppm of Zn, 21.87 ppm of Cu, 81.25 ppm of Mn, and 2.18 ppm of Cr. The experiment was carried out for a total of 180 days. According to the findings, there was no significant impact of specific trace minerals supplementation on the animals' body weight, morphometric parameters, dry matter intake, average daily gain, nutritional value, digestibility and nitrogen retention. However, higher levels of Zn, Cu, and Mn led to increased (p < 0.05) total retention, while Cr retention remained the same. Serum mineral concentrations of Zn, Cu, and Mn increased significantly (p < 0.05) in G2 and G3 compared to the G1 group while Ca, P, and Cr had no significant change. Blood plasma glucose, albumin, globulin, and total protein showed no significant differences. Plasma alkaline phosphatase activity improved significantly (p < 0.05) in G2 and G3 but alanine transaminase, aspartate aminotransferase, hemoglobin, hematocrit, and IGF-1 remained unchanged. Superoxide dismutase activity, ferric-reducing antioxidant power, and total immunoglobulin concentration increased significantly (p < 0.05) in G2 and G3 groups, however, catalase activity and IgG count did not change among the groups. Mineral-supplemented groups (G2 and G3) showed a significant change (p < 0.05) in testosterone production during the 120th and the 180th day of the trial. Scrotal circumference and temperature gradient of the scrotal surface did not show any significant change. Supplementing growing bull calves with specific trace minerals above the basal level (70, 17.50, 65 and 1.75 ppm of Zn, Cu, Mn and Cr) has no direct beneficial effect on the growth parameters but can have positive effects on their antioxidant status, immunity and reproductive development as the related blood parameters were positively affected.

The infrared thermography of the scrotal surface in the long scrotum bull. Preliminary comparisons to normal scrotum for breeding bulls

The infrared thermography of the scrotal surface in the long scrotum bull. Preliminary comparisons to normal scrotum for breeding bulls

Thermal imaging to measure scrotal surface temperature and its use as a tool for breeding soundness evaluation of Zebu bulls

The present study was planned to understand the effect of scrotal surface temperature on semen quality and Infrared thermography as a tool for breeding soundness evaluation of Zebu bulls. The thermal imaging of the scrotum revealed significant differences in temperatures from the neck to the ventral portion of the scrotum. The average neck and ventral temperature of the scrotum was 34.2±0.62°C and 31.22±0.53°C, respectively. The average gradient temperature of the scrotal surface (neck-ventral) was 2.95±0.30°C with a range of 1.2-5.7°C. The MA of bull semen (3.12±0.04 vs. 1.89±0.13), live sperm (73.82±0.88% vs. 59.42±1.58%), HOST (66.67±1.52% vs. 55.49±1.14%) and sperm concentration (1226.36±18.80 vs. 942.19±23.47m/ml) were significantly more in good semen quality bulls than poor semen quality bulls. Total sperm abnormality was significantly lesser in bulls having a larger scrotal temperature gradient. The scrotal skin thickness was significantly more in poor semen quality bulls than good semen quality bulls (5.70±0.12 vs. 5.07±0.13). The scrotal skin thickness was found highly correlated (r-0.77) with the scrotal temperature gradient. So it can be concluded that scrotal surface temperature is related to the semen quality of bulls, and thus the thermal imaging can be used for breeding soundness evaluation of Zebu bulls.

In vivo dosimetry for testicular and scalp shielding in total skin electron therapy using a radiophotoluminescence glass dosimeter

Mycosis fungoides (MF) is a common, low-grade non-Hodgkin’s lymphoma of skin-homing T lymphocytes that can be treated via skin-directed radiotherapy. Our institution has implemented total skin electron therapy (TSET) with a 4.3 m source-to-surface distance (SSD) and 6 MeV electron beams with a beam spoiler. A 35-year-old male undergoing TSET desired to avoid radiotherapy-induced hair loss and temporary infertility; therefore, leakage dose to scalp and testicles was reduced with a special radiation shield composed of stacked lead sheets. The shields for the scalp and scrotal were of 3 mm and 6 mm, respectively. To assess leakage doses, a radiophotoluminescence glass dosimeter (RPLD) was placed at every fraction. The difference dose between the measured and prescribed dose at the calibration point was 2%. The top of the head and scrotal surface exhibited 18 cGy and 10 cGy, respectively. Thus, the dose to the scrotal surface was not beyond the testicular tolerance dose of 20 cGy. Results of semen analysis two months postradiotherapy were normal. There was no hair loss during or after radiation therapy. Therefore, the RPLD is a useful in vivo dosimeter that provides technical information on radiation shielding to allow for completion of TSET without hair loss or temporary infertility.

Testicular Shielding for Total Body Irradiation in Pediatric Patients: A Single Institution's Approach

Total body irradiation (TBI) has been used as a part of the conditioning regimen for patients undergoing hematopoietic stem cell transplantation (HSCT) for certain non-malignant conditions such as sickle cell disease. While effective, TBI can cause lasting side effects for pediatric patients including oligospermia or even permanent azoospermia. Although many investigators have studied testicular shielding during TBI for non-malignant conditions, there is no set standard. The purpose of this study is to describe a different technique to conduct testicular shielding in male pediatric patients undergoing TBI for non-malignant conditions.We describe three patients who underwent TBI as part of their conditioning regimens for allogeneic HSCT. The testicular shielding technique is reported, together with the optically stimulated luminescence dosimeter (OSLD) results for the gonads. For the patients being treated in the upright, sitting position with AP/PA fields, the testicular shielding was placed using the shadow from the field light. For the patient treated in the decubitus position with AP/PA fields, a surface rendering was generated using the treatment planning system which guided the physical placement of the gonadal block. OSLDs were placed in the middle of the scrotal surface, behind the gonadal blocks, for both the AP and PA orientations to verify the delivered dose to the testicles.The OSLD readings for patient 1 indicated a dose of 43 cGy to the gonads for the first TBI course, a 78.5% decrease from the prescribed dose of 200 cGy. For the second TBI course, this patient received a total dose of 63 cGy to the gonads, an 84.3% decrease from the prescribed dose of 400 cGy. The OSLD readings for patient 2 indicated a dose of 31 cGy to the gonads for the first TBI course, an 84.5% decrease from the prescribed dose of 200 cGy. For the second TBI course, patient 2 received a total dose of 75 cGy to the gonads, an 81.3% decrease from the prescribed dose of 400 cGy. The OSLD readings for patient 3 indicated a total dose to the gonads of 29 cGy, an 85.5% decrease from the prescribed dose of 200 cGy.We report here an effective technique to shield the testicles of male pediatric patients undergoing TBI. We verified that our technique reduces the testicular dose by approximately 80- 85% of the TBI prescription dose in three male pediatric patients, keeping the dose well below the documented doses that can cause permanent infertility and hypogonadism.

Scrotal thermographic profile and seminal characteristics of Mangalarga Marchador stallions bred in the Atlantic Rainforest biome

ABSTRACT The objective of this study was to determine the scrotal thermographic profile and to verify the influence of temperature and humidity of the humid tropical climate on testicular temperature and seminal quality of Mangalarga Marchador stallions. The thermal profiles of the proximal, middle, and distal zones of the testicles and total surface temperature (TSTT) were recorded using an FLIR E60bx thermal imager. The average air temperature (°C) and relative humidity (%) were obtained 1, 5, 9, 33, and 66 days before semen collection and showed a mean value of 26.5±2.4 and 80.4±6.0 respectively. The scrotal surface temperature was close to 34°C and there was no variation with the age of the stallion, reproductive activity, and characteristics of the ejaculate (P&gt;0.05). The only significant correlations obtained were between TSTT and minor defects (R = 0.41; P&lt;0.05), between TSTT and total defects (R = 0.46; P&lt;0.01), and between TSTT and percentage of morphologically normal sperm (R = -0.46; P&lt;0.05). It was concluded that the Mangalarga Marchador stallions maintained the testicular temperature within favorable conditions for spermatogenesis, demonstrating the efficiency of testicular thermoregulation mechanisms in the Atlantic Forest biome.

Testicular Temperature and the Effects of Orchiopexy in Infants with Cryptorchidism.

Testicular temperature should remain low to maintain optimal function of germ cells; however, information regarding testicular temperature in infants and the effect of cryptorchidism and its correction, including laparoscopic staged Fowler-Stephens orchiopexy (LSFSO), is limited. A total of 82 infants with unilateral palpable cryptorchidism, 24 with nonpalpable testes who underwent unilateral LSFSO and 20 with scrotal hydrocele were included. Ultrasonographic determination of testicular volume and measurement of testicular temperature but not scrotal surface temperature using a Coretemp CTM204® (Terumo, Tokyo) were performed before and 12 months after orchiopexy. The effects of the route of testicular delivery, conventionally through a new hiatus medial to the inferior epigastric vessels or through the transinguinal approach, were investigated in the LSFSO cases. Undescended testicular volume was significantly increased after orchiopexy (0.80 ml to 0.92 ml, p <0.0001). The preoperative testicular temperature (35.1C) was significantly higher than that of the control (34.4C, p <0.0001), and significant decreases in testicular temperature occurred after orchiopexy (34.3C, p <0.0001). A multivariate analysis showed that a decrease in testicular temperature was a factor associated with postoperative testicular development. Twelve months after LSFSO, transinguinal approach was shown to be more effective in decreasing the testicular temperature than the conventional approach (34.4 and 35.3C, respectively, p <0.05). Orchiopexy is effective in correcting the high-temperature environment caused by cryptorchidism. In the case of nonpalpable testes treated by LSFSO, transinguinal fixation is more effective than the conventional approach in reducing testicular temperature, but a longer followup period is necessary to draw a final conclusion.

A comparison of immunological, chemical and surgical castration of Nelore bulls

The objective was to compare effects of immunological, chemical and surgical castrations on testicular characteristics, scrotal surface temperatures, sperm quality, and serum testosterone concentrations in Bos indicus bulls. Eighty Nelore bulls (∼20 mo) were grazed on pasture, fed a supplement and slaughtered at ∼480 kg. Bulls were allocated into four groups (n = 20/group). The control group (CON) was non-castrated and there were three castration methods: immune (IMM - Bopriva®), injected on D-30, D30 and D60; chemical (CHE), an intratesticular injection of 40% CaCl2 + 0.5% dimethylsulfoxide on D0; and surgical (SUR) on D0. The CHE group were surgically castrated on D60, due to testicular swelling and necrosis of scrotal skin. Most scrotal surface temperatures (infrared thermography) were significantly higher on D15 in CHE and SUR compared to CON, due to inflammation. All bulls were subjected to a breeding soundness evaluation on D-7 and slaughtered on D220. Scrotal circumference and testicular volume did not differ among groups (P > 0.05) at D0, but at D15, both end points were highest (P < 0.05) in the CHE group (due to swelling), although both end points were smaller for IMM versus CON (P < 0.05) at D60 and D150. Sperm motility in the IMM group was ∼50 and 10% of that in the CON group on D60 and D150, respectively. For the IMM group, serum testosterone concentrations were similar on D0 and D15 (but ∼50% of CHE or SUR on D0, attributed to the first treatment on D-30), and had decreased ∼70% on D60 and D150, whereas in the CHE and SUR groups, there were ∼80–90% decreases in testosterone after D0. In conclusion, immunological castration was a viable alternative to surgical castration, as it supressed testosterone production and spermatogenesis, with the benefits of being much less invasive, with better animal welfare and less stress.

Efficacy of topical testosterone in management of scrotal hypoplasia and agenesis

Scrotal hypoplasia or agenesis may posses difficulty during orchidopexy or end with social anxiety around excessively small scrotal size when compared to peers, and where there may be concerns regarding the future sexual life. Any conservative modality applicable to ameliorate scrotal underdevelopment partially or completely will be useful either solely or before reconstructive surgery. Seventeen child (3-8 years) were diagnosed with bilateral scrotal hypoplasia (SH) in 5 unilateral in 7, bilateral scrotal agenesis (SA) diagnosed in 4 cases, and unilateral in one. Testicles are either undescended, ectopic, or normal. All cases managed by Testogel 1% topical testosterone for 4 weeks. Clinical assessment by measurements of the scrotal skin surface area (scrotal length multiplied by width) and scrotal corrugations counting. Inguinal and renal ultrasound done for all cases and karyotyping for cases of agenesis and cases with bilateral undescended testicles. Total and free testosterone, LH, FSH and AMH hormones were assisted before treatment, weekly and one week after therapy. Data analyzed and evaluated, difference of means used to test for statistically significant differences between scores of scrotal development. Free and total testosterone elevated in the 1st week of treatment, but restored to normal or higher levels in 60% of cases at the 2ndweek. Satisfactory response (Increasing numbers of scrotal rugae or scrotal surface area by 30-50% above the pretreatment status) obtained in 85% and 60% of unilateral and bilateral SH, but only a partial response (10-20% increase) was gained in 40% of cases with agenesis. No major adverse effect was appreciated. Response of some cases of SH to topical testosterone indicates presence of remnants of labioscrotal folds with testosterone receptors (Bell etal., 1971) [1]. Testosterone replacement therapy can improve the signs and well-being of a hypogonadal male by restoring serum testosterone concentrations to physiologic levels. In this study the mean average testosterone concentration one week after application of testogel was 13.47±2.45 and 12.12±2.5 within 2nd, 4th week, and after cessation of treatment. Anti-Mullerian hormone is significantly low in 12 cases; mainly in cases of SA (P-value <0.001). Short term topical testosterone proved to be effective in a considerable percentage of cases of either bilateral or unilateral scrotal hypoplasia; with a subsequent increase in scrotal surface area and number of rugae, it may substitutes the indication for surgical reconstruction. Long term follow up is a limitation of this study.

Chronic excessive Zn intake increases the testicular sensitivity to high ambient temperature in Bama miniature pigs

Zinc (Zn) can accumulate in the body of wild animal and human through bio-magnification effects in the food chain to pose chronic toxicity. Male spermatogenesis was sensitive to excessive Zn and elevated temperature. This study aimed to examine whether or not excessive Zn intake caused testicular toxicity and estimate the interaction between Zn and high temperature (HT) in testes of Bama miniature pigs. Six-month-old pigs were pre-fed with or without additional Zn at 1500 mg/kg diet for 30 d and afterward subjected to HT at 40 °C for 5 h daily for 8 consecutive days. Blood samples were collected on d 31 and d 38 and testes were obtained on d 38 immediately after HT exposure. Our data showed both scrotal surface temperature (T) and body surface T increased after 5-h HT exposure (p < 0.05). Pigs fed with additional Zn showed germ cell loss, the decreased testes weight (p < 0.01) and the elevated testicular H2O2 level (p < 0.05) as exposed to HT. In additional Zn groups, the autophagosomes or autolysosomes were more frequently observed in the Leydig cells and abnormal acrosomes increased in spermatids. Additional Zn diet increased p62 protein level (p < 0.05), decreased testicular Zn concentration (p < 0.01) and down-regulated the relative mRNA expression of heme oxygenase 1 (p < 0.05). There were significant interactions between T and Zn on testes weight, the relative weight of testes, testosterone concentration on d 31, and the relative mRNA expression of Zn transporters 1 and 2. In conclusion, chronic excessive Zn diet impacted testicular Zn concentration and made the testes more vulnerable to heat, leading to testicular toxicity in Bama miniature pigs.

Scrotal infrared thermography and testicular biometry: Indicator of semen quality in Murrah buffalo bulls

This aim of this study was to assess the relationship, if any, of scrotal surface temperature gradient (SSTG), scrotal circumference (SC) and testicular covering thickness (TCT) with semen quality in Murrah buffalo breeding bulls. For this, buffalo breeding bulls (n = 130) were selected from four different semen centres. The ejaculates of each bull were evaluated for ejaculate volume (EV), mass motility (MM); concentration (SPC), motility (SM), viability and abnormalities (SA). The SSTG, SC and TCT of individual bulls were quantified using digital infrared thermography, measuring tape and ultrasonography, respectively. The bulls were divided into three groups on the basis of SSTG (≤ 4 °C, 4.1 to 6.4 °C and ≥ 6.5 °C), and SC (<31, 31 to 35 and> 35 cm) and into two groups on the basis of TCT (5 to 7.2 and 7.4 to 10.4 mm). Results indicated the bulls with a larger temperature gradient and larger SC produced greater quality semen than those with a lesser temperature gradient. The MM (P < 0.01) and SPC (P < 0.05) varied among the groups along with SSTG. Among the SC groups the EV, MM, SPC and SM (P < 0.01), and viability (P < 0.05) varied as did the SC. The bulls with a lesser TCT had a lesser SA (P < 0.05) as compared to the group with the greater TCT. Buffalo bulls having a greater SSTG, SC and lesser TCT produced semen of greater quality and these variables may be used as criteria for breeding soundness evaluation.

Use of scrotal infrared thermography and ultrasonography to understand thermoregulation of testis and sperm quality in Karan Fries breeding bull

The present investigation was carried out to study the effect of testicular covering thickness, scrotal circumference and scrotal surface temperature gradient insert semen quality attributes of Karan Fries breeding bull. Six ejaculates were collected from each randomly selected bulls (n=15), and seminal quality attributes were evaluated during peak winter season. Same time scrotal surface temperature gradient (SSTG), the thickness of testicular covering (TTC) and scrotal circumference (SC) of individual bulls were recorded using DarviDTL007 infrared thermography camera, ultrasonography and measuring tape, respectively. Three groups were formed based on SSTG (Group I- £ 4 oC, Group II- 4.1 to 6.8 oC and Group III- ³6.9 oC), two groups based on TTC (Group I- 3.03 to 4.85 and Group II- 4.86 to 7.03 mm) and SC (Group I- 32 to 35 and Group II- 36 to 41 cm). Ejaculate rejection rate (ERR) was significantly decreased with the increase of SSTG and SC. ERR was not affected with TTC. The increase of SSTG (from GroupI to Group III), mass activity and non-eosinophilic sperm count were significantly increased, and sperm abnormalities were significantly (p<0.01) decreased. Similarly, with the increase of SSTG and abnormalities were significantly (p<0.01) increased among different groups. Ejaculate volume and non-eosinophilic sperm count were significantly (p<0.01) increased with SC group I and group II. It can be concluded that scrotal surface temperature gradient was a better indicator of semen quality as compared to the thickness of testicular covering and bulls having a higher scrotal surface temperature gradient, scrotal circumference and lower thickness of testicular covering produced better quality semen.

Differences in the thermal sensitivity and seminal quality of distinct ovine genotypes raised in tropical conditions

For different ovine breeds to maximize their reproductive capacity in countries with tropical climate, it is important to evaluate their potential for thermal resilience and consequences on their reproductive traits. Therefore, the objective of this study was to evaluate the effect of thermal environment temperatures of climate seasons in a tropical climate region on the surface temperatures of the scrotum, testicular biometric characteristics, seminal quality and serum testosterone concentration of rams of different genotypes. Breeders of four different genotypes (Dorper, n = 8, Texel, n = 8, Santa Inês, n = 9 and Morada Nova, n = 8) were used throughout the four climate seasons. Higher thermal challenge was recorded in the spring and summer. In the summer increase in scrotal surface temperature was detected by infrared thermography (P < 0.05), mainly in the regions of the distal testicular pole and tail of the epididymis. The animals of the Texel genotype had higher rectal temperature in the summer. In spring, this genotype also had the highest testicular pole (32.2 ± 0.5 °C; P < 0.05) and distal (29.9 ± 0.4 °C; P < 0.05) temperatures and a higher mean testicular temperature (31.7 ± 0.4 °C; P < 0.05). The Morada Nova genotype showed a higher surface temperature gradient between testicular poles (2.96 ± 0.1 °C; P < 0.05), especially in spring. Genotype-dependent thermal sensitivity was detected for the thermal gradient between the testicular poles, reflecting the seminal quality. There was a positive correlation of the thermal gradient between testicular poles with sperm membrane integrity and negative correlation with total sperm defects. The Texel genotype showed less progressive motility and higher percentage of sperm defects. There was no difference in testosterone concentration between genotypes and in the different seasons (P > 0.05). Thus, the indigenous genotypes showed a greater capability to maintain the scrotum-testicular thermoregulation. Dorper animals resembled the indigenous sheep genotypes, in terms of seminal characteristics, unlike Texel animals, which showed lower adaptability and lower seminal quality.

Study on semen quality in relation to scrotal surface temperature gradient, testicular covering thickness and scrotal circumference in Murrah bulls

Present study was carried out to evaluate the effect of scrotal surface temperature gradient, testicular covering thickness and scrotal circumference on semen quality in Murrah bulls. Murrah buffalo bulls (n = 18), were selected from Artificial Breeding Research Centre, ICAR-National Dairy Research Institute, Karnal, Haryana, for the present study. Testicular parameters viz. scrotal surface temperature (SST), scrotal circumference (SC) and testicular covering thickness (TCT) of individual bulls were measured. Temperature of scrotum (Proximal Pole Temperature, Mid Pole Temperature, Distal Pole Temperature, Right Epididymis and Left Epididymis) was measured three times a day per week during peak winter season. Semen quality attributes viz., volume, mass motility, non-eosinophilic sperm and sperm abnormalities of each ejaculate were evaluated. The TCT and SC were measured by using ultrasonography and measuring tape, respectively. The bulls were divided into three groups on the basis of scrotal surface temperature Gradient (SSTG) (Group I- ≤ 4 oC, Group II- 4.1- 6.8 oC and Group III- ≥6.9 oC) and into two Groups on the basis of TCT (Group I- 4.53-5.28 and Group II- 5.36-7.36 mm) and SC (Group I- 28-31 and Group II- 32-35 cm). Mass activity and non-eosinophilic sperm count was improved significantly (P<0.05) and head, midpiece, tail and total abnormalities were reduced significantly (P<0.05) with increase in SSTG. The significant (P<0.05) effect of TTC on sperm abnormalities was observed. Ejaculate volume and non-eosinophilic sperm count increased significantly (P<0.05) with increase in SC. In conclusion scrotal surface temperature gradient, thickness of testicular coverings and scrotal circumference significantly affected semen quality in Murrah buffalo bulls.

Dietary l-arginine supplementation improves semen quality and libido of boars under high ambient temperature

l-Arginine is a nutritionally essential amino acid for spermatogenesis and plays versatile roles in animal health and can be utilized as a potential agent to improve reproductive performance of boars under high ambient temperature. The present study aimed to determine whether dietary l-arginine could alleviate heat stress-induced infertility in boars. In all, 20 boars (PIC 1040; 248.59±3.84 kg BW and 407.65±6.40 days of age) were selected and randomly assigned to four groups (group 0.0%, basal diet; group 0.6%, 0.8% or 1.0%, basal diet added with 0.6%, 0.8% or 1.0% l-arginine (wt:wt), respectively.) The four diets were made isonitrogenous by addition of appropriate amounts of l-alanine. Boars were pre-fed the corresponding experimental diet for 42 days. Then, the semen characteristics and libido were accessed for 6 weeks during the hot summer period (25.5° to 33.0°C). Results show that dietary l-arginine remarkably improved sperm motility, normality, total sperm number and effective total sperm number. Also, dietary l-arginine improved semen antioxidant capacity, such as decrease of malondialdehyde and 8-Hydroxy-2'-deoxyguanosine content in sperm (P<0.05), increase of the ratio of glutathione and oxidized glutathione, total antioxidant capacity, glutathione peroxidase and catalase activities in seminal plasma (P<0.05). Most of mitochondria contained intact ultrastructure in l-arginine-supplemented group which also accompany with higher ATP content than the 0.0% group. The boars fed 0.8% l-arginine show increased levels of estradiol-17β and testosterone and exhibit improved libido performance than boars in the 0.0% group. Adding dietary l-arginine linearly increased (P=0.002) nitric oxide content (as l-arginine increased). The scrotal surface temperature in the 0.6%, 0.8% and 1.0% group were decreased by 0.9°C, 0.9°C and 0.4°C, respectively, compared with the 0.0% group. l-Arginine levels caused linear effect on semen quality and antioxidant capacity, also caused quadratic effect on libido performance. During the hot summer months, the predicted optimal l-arginine levels for best semen quality and antioxidant capacity was 0.8% to 1.0% and for best libido performance was 0.8%. It can be concluded that l-arginine can be used as an effective agent to alleviate heat stress-induced infertility of boar, and that 0.8% to 1.0% can be considered as the optimum dosage.

Autophagy involved in the activation of the Nrf2-antioxidant system in testes of heat-exposed mice

Hyperthermia causes oxidative stress in testes, which triggers antioxidant signals including autophagy and nuclear factor erythroid 2-related factor 2 (Nrf2). However, their relationship in testes under oxidative stress is unclear. In this study, we conducted testes injection for autophagy alteration and heat exposure to reveal the interaction between autophagy and the Nrf2-antioxidant system. Male mice were injected once with normal saline as control (Cont group), autophagy inhibitor 3-methyladenine (3-MA group) or autophagy inducer rapamycin (Rapa group). Then, each group was divided into two parts: one received a 2-h 42°C heat treatment for eight days (HT groups), and the other was kept thermal neutral (NT groups). Heat-exposed mice showed significantly increased rectal, scrotal surface and body surface temperatures. Histology of the testes revealed many vacuoles inserted in the seminiferous tubules in the HT Cont group and two 3-MA groups. Ultrastructural changes in germ cells revealed autophagosomes in two 3-MA groups. Immunohistochemical detection of Nrf2 and p62/SQSTM1 proteins showed prominent expression in Leydig cells. Heat exposure increased Nrf2 protein and mRNA levels. 3-MA and Rapa testes injection also resulted in Nrf2 cytoplasm accumulation. Massive conversion of LC3 (microtubule-associated protein light chain 3)Ⅰ to LC3Ⅱ was detected in two 3-MA groups, accompanied by decreased ATG5 (autophagy related gene 5) mRNA levels in the HT 3-MA group. These results indicated autophagy alteration triggered the Nrf2 signaling pathway with consequences such that the autophagy inducer protected the testes and the autophagy inhibitor enhanced the detrimental effects caused by heat exposure.