The use of ultrasonography in the reproductive evaluation of boars

The objective was to study the use of ultrasound as a complementary test in the breeding soundness evaluation in male pigs and study the pattern of echogenicity of the testicular parenchyma in boars of different racial groups. Twenty‐six adult boars from four different racial groups were used, 10 from the Piau breed (group 1), four from the commercial and finishing group (group 2), six Pietrain breed (group 3) and six from the Duroc breed (group 4). All animals were evaluated for breeding soundness evaluation and the ultrasound examination of the testicles. The groups of animals that were evaluated showed no difference in the main semen parameters that were evaluated, except for the sperm volume, concentration of the ejaculated sperm and the supravital staining; the lowest figures were for the animals from the Piau breed (group 1). In relation to the testicular biometrics, Duroc animals (group 4) had a greater scrotal width compared to the other groups. But when we assessed the intensity of pixels of the testicles, there was a difference between groups. The groups 2 (finishing animals), 3 (Pietrain) and 4 had no difference between themselves. Group 3 had greater pixel intensity in relation to group 1. Of the 26 animals studied, five showed an abnormality during ultrasound evaluation, like hydrocele, hyperechoic mass in the testicular parenchyma, cyst in the head of the epididymis and the presence of fluid in the head and tail of the epididymis. The various animal groups studied did not differ in the principal reproductive parameters evaluated, showing that despite the great variability of reproductive traits between breeds and within the same breed, the breeding soundness evaluation, the more complete it is, is essential for the selection of breeders and the ultrasonography of the reproductive system becomes an important addition in this examination.     

Effects of five cryoprotectants on proliferation and differentiation‐related gene expression of frozen‐thawed bovine calf testicular tissue

The cryopreservation of testicular tissue is a potential method for preserving male fertility. However, the effect of cryopreservation on bovine calf testicular tissue is scarce. This study investigated the effect of different cryoprotectants on bovine calf testicular tissue at the molecular level. Testicular tissue from ten immature bovine calves (6 months) was collected after slaughter and cryopreserved in an extender containing different concentrations of the following five cryopreservation solutions (CP): bovine serum albumin (BSA) with 5% dimethyl sulfoxide (DMSO), trehalose with 5% DMSO, DMSO and glycerol and ethylene glycol (EG). After 7‐day cryopreservation, the expression levels of three spermatogonial stem cell (SSC)‐related genes, octamer‐4 (OCT4), KIT ligand (MGF/SCF) and kit oncogene (C‐KIT), were investigated by quantitative PCR (qPCR). The cell viability was highest for the tissues preserved with 30 mg/ml BSA (77.82% ± 1.22) and 40 mg/ml trehalose (74.23% ± 1.16) compared with other groups (p < 0.05), and the level of expression of the three genes was highest with 30 mg/ml BSA (p < 0.05). Compared with other CPs, the 30 mg/ml BSA and 40 mg/ml trehalose have the better cryopreserve protection. The 30 mg/ml BSA is the most viable media for the cryopreservation of testicular tissue from cattle.     

Assessment of age-related morphological changes in the testes of post-hatch light ecotype Nigerian indigenous chicken

The age-related morphological changes of the testes in light ecotype Nigerian indigenous chicken were evaluated in this study using gross anatomical, histological and histomorphometric techniques. The results showed that the testes of 3- to 9-month-old birds were light pink while testes of sexually mature chicken were creamy white in colour. The left and right testicular weight, length, diameter, circumference and the organosomatic indices increased significantly (p < .05) with increasing age across the groups. Although the mean tubular diameter and epithelial height of the left and right seminiferous tubules increased significantly (p < .05) with age, the tubular diameter, epithelial height and luminal diameter did not vary significantly (p > .05) between the left and right testes of all the groups. The one-cell layer thick germinal epithelium of the left testes at 3 to 6 months old showed islands of cell proliferation that contained spermatogonia and spermatocytes. At 6 to 9 months, the left testes exhibited numerous early spermatids with occasional occurrence of late stage spermatids while the right testes showed scanty early stage spermatids. At 12 to 18 months, the germinal epithelia of both left and right testes were characterized by the presence of Sertoli cells, spermatogonia, primary spermatocytes, numerous early and late stage spermatids as well as spermatozoa. In conclusion, the morphological features highlighted in the present study show that at pre-pubertal periods, the left testes may develop faster than the right testes. However, both left and right testes may participate actively in the production of spermatozoa during the post-pubertal life.     

Assessment of the accuracy of testicular dysfunction detection in male donkey (Equus asinus) with the aid of colour-spectral Doppler in relation to plasma testosterone and serum nitric oxide levels

This study aimed to determine the usefulness of colour and pulsed Doppler modes for the accurate diagnosis of donkeys suffering from subfertility to determine whether testicular vascularity assessment could be an indicator for sperm functionality. The study sample was composed of 10 male donkeys with normospermia (control group) and 10 donkeys with hypospermia. Animals underwent scrotal circumference measurement, testicular Doppler examination, seminal evaluation, blood sampling and hormonal assay. Semen volume and concentration were significantly (p ≤ .05) lower in the subfertile group (30.25 ± 1.22 ml and 89.44 ± 2.55 × 10⁶/ml) as compared with the control group (82.76 ± 1.65 ml and 452.78 ± 1.25 × 10⁶/ml), and total sperm/ejaculation was significantly (p ≤ .05) higher in the normal donkeys (28.30 ± 2.32 × 10⁹/total ejaculated) as compared with the subfertile group. Intratesticular coloured area showed a marked decline in the hypospermic males. There was no significant difference between the two groups in testosterone level, although the normal group showed an increase in nitric oxide metabolites. Both Doppler indices of the three branches of the testicular artery were elevated significantly (p ≤ .05) in abnormal donkeys, whereas Doppler peak systolic and end-diastolic velocities were increased in the normal group. Male donkeys with subfertility demonstrated lower arterial vascularity parameters in the form of intratesticular coloured area and blood flow rate; therefore, the most optimal parameters for differentiating subfertile hypospermic from normospermic donkeys were found to be the two Doppler indices, velocities parameters, testicular blood flow rate and nitric oxide levels.     

不同品种公猪睾丸、精液品质发育规律及相关性研究

为明确公猪睾丸在选育中的意义,研究公猪睾丸参数、精液质量参数的发育性规律以及两者间的关联性。选择936头分布在280～1 409日龄的生产公猪,其中589头杜洛克、233头长白、114头大白。对睾丸和精液质量参数采用一般线性模型,以品种和日龄分组为固定因素进行多变量分析;使用二次项模型分品种分别对睾丸总体积和有效精子数进行发育曲线拟合;控制日龄变量,对睾丸与精液质量参数进行偏相关性分析。在睾丸大小方面：杜洛克>大白>长白,其中杜洛克与大白差异不显著（P>0.05）,但两者均极显著（P<001）高于长白;在精液质量整体比较上：长白优于杜洛克优于大白,但差异不显著（P>0.05）;但在体积、密度、活力和畸形率上,三品种公猪均存在显著（P>0.05）或极显著(P<0.01)差异;睾丸随日龄增长呈先增大后萎缩趋势,精液整体质量随日龄增长呈下滑趋势;三品种公猪睾丸的大小均与精液量和有效精子数呈正相关,且大部分具有显著（P<0.05）或极显著性(P<0.01)。同日龄时期,三品种公猪睾丸的大小顺序为杜洛克>长白>大白,其中长白大于大白具有普遍性; 综合来看,三品种的精液质量比较结果为长白优于杜洛克优于大白,其中长白优于大白具有普遍性;公猪睾丸萎缩临界日龄可用于公猪淘汰依据,选育公猪时可重点选留睾丸较大者。     

Differentiation and development of Leydig cell, and induction of spermatogenesis during testicular differentiation in the Japanese eel, Anguilla japonica

The initial appearance and the development of Leydig cells (LCs), the sites of steroid hormone production in the testis, were investigated ultrastructurally during testicular differentiation in the Japanese eel, Anguilla japonica. In addition, the effects of a single injection of human chorionic gonadotropin (HCG; 5 IU g body weight^-1) on histological changes of the testes and serum 11-ketotestosterone (11-KT) were examined at various stages (15–18, 20–23, 26–29, 32–35, 38–41 and 46–50 cm body length (BL)) of testicular differentiation. Testicular differentiation was morphologically characterized by the development of loose connective tissue on the medial side in animals 18–29 cm in BL. Ultrastructurally, LCs were first identified in the loose connective tissue of the testis of the 23 cm fish. In the testes of fish over 32 cm, clusters of LCs were distributed throughout the interstitial region accompanying the increase in number of spermatogonia. In fish larger than 32 cm, spermatogenesis was induced by administration of HCG; serum 11-KT levels were also raised. On the other hand, there was no effect on spermatogenesis or serum 11-KT levels in fish less than 29 cm, or in the controls. These result suggests that morphological differentiation of LCs occurs in testis of the 23 cm eel, and subsequently, the testes of eels of BL more than 32 cm acquire the capability to produce steroid hormones.     

Estimation of the total surface area in Indian elephants (Elephas maximus indicus)

Twenty-four adult Indian elephants (Elephas maximus indicus) of both sexes and different ages and weights, belonging to the Temple Devaswoms, the Forest Department of the Government of Kerala and the Gemini Circus formed the experimental subjects from which formulae were derived to predict the total surface area from either body measurements or areas of individual regions. Several models, using the parameters studied either singly or in combination, were tried independently for males and females and also for adults irrespective of sex. The best prediction of total surface area (S) in m² was obtained for adults irrespective of sex by using the two parameters, the height at the shoulders (H) in m and forefoot pad circumference (FFC) in m in the formula S=–8.245+6.807H+7.073FFC. No significant improvement in the accuracy of prediction resulted from the use of the independent best fit formulae for males and females. The conventional method of using the exponential of body weight (kg) for predicting suface area was not found to yield an equivalent accuracy in these animals.