Necrotic enteritis in collared (Pecari tajacu) and white-lipped (Tayassu pecari) peccaries

An outbreak of necrotic enteritis caused by Clostridium perfringens type C was diagnosed in captive collared (Pecari tajacu) and white-lipped (Tayassu pecari) peccaries housed in the Laboratory of Applied Ethology of Universidade Estadual de Santa Cruz located in Ilhéus, State of Bahia, Brazil. Four collared peccaries and three white-lipped peccaries, all juveniles (25-105 days old), were affected. For all affected animals, lethargy and inappetance were followed by sudden death within 24 hours. Histopathology of intestinal wall, culture of C. perfringens type C, and the identification of beta-toxin from intestinal content confirmed the diagnosis.     

Transitional cell carcinoma metastatic to the eye in a collared peccary (Tayassu tajacu)

A 15-year-old female collared peccary (Tayassu tajacu) was presented for ophthalmic examination following sudden onset of blindness. Bilateral retinal detachment was diagnosed, neoplasia suspected, and euthanasia performed. Widespread tumor dissemination was apparent at autopsy, and transitional cell carcinoma was diagnosed histologically. The tumor was identified as arising from the ovary. Epidemiologic features of this case are discussed.     

Morphological Characterization of the Ovarian Preantral Follicle Population of Collared Peccaries (Tayassu tajacu Linnaeus, 1758)

The aim of this research was to characterize the preantral ovarian follicular population in collared peccaries (Tayassu tajacu) using light and electron microscopy. Ovaries from six mature females were collected and further fixed for histological and ultrastructural analysis. A total of 33273.45 ± 5789.99 preantral follicles (PFs) were estimated for the population in each ovary. Most preantral follicles were primordial (91.56%), followed by primary (6.29%) and secondary (2.15%) ones. Most PFs were morphologically normal (94.4%), and only a few were atretic (5.6%). At histology assessment, amounts of lipid droplets were observed into the oocyte cytoplasm, which was confirmed through ultrastructural analysis. This work characterizes for the first time the ovarian population of preantral follicles, total and per category, in collared peccaries (Tayassu tajacu). The general follicles featured at primordial, primary and secondary categories are very similar to those described for other species.     

SEM and neurohistological observations of nerve endings in the middle region of the tongue of the collared peccary (Tayassu tajacu): a silver impregnation method

The presence of lingual papillae and the nerve endings in the middle region of the tongue mucosa of collared peccary (Tayassu tajacu) were studied using scanning electron microscopy and light microscopy, based upon the silver impregnation method. The middle region of tongue mucosa revealed numerous filiform and fungiform papillae. The thick epithelial layer showed epithelial cells and a dense connective tissue layer containing nerve fibre bundles and capillaries. The sensory nerve endings, intensely stained by silver impregnation, were usually non-encapsulated and extended into the connective tissue of the filiform and fungiform papillae very close to the epithelial cells. In some regions, the sensory nerves fibres formed a dense and complex network of fine fibrils. The presence of these nerve fibrils may characterize the mechanisms of transmission of sensitive impulses to the tongue mucosa.     

rob(13/17)纯合子猪的联会复合体分析

采用表面铺展法和硝酸银染色技术对rob(13/17)纯合子猪减数分裂的配对行为进行了联会复合体（synaptonemal complex,SC）的电镜观察和分析。结果表明，rob(13/17）纯合子猪的SC配对行为正常，未见三价体和侧生组分形成。SC的形成开始于偶线期，成熟于粗线期，解体于双线期。在减数分裂前期，性染色体轴呈强嗜银性，配对明显落后于常染色体。根据减数分裂前期性染色体的形态和行为，把性染色体的SC分为4个类型。     

Histological organization of collared peccary (Tayassu tajacu) lip

Collared peccary (Tayassu tajacu) belongs to the Tayassuidae family that is characterized by a dorsal scent gland located in the middle of the hump. It can be found from south-west United States to Argentina. It is a very well-adapted animal that can survive different environments, having a varied diet. Very little morphological information of the animal is available, except that concerning the reproductive tract. This study describes the histological organization of the collared peccary lip. The lip marks the junction between the integument and digestive system. It is lined by skin on the outer surface and mucosa on the inner surface. Skin appendages such as hair follicles and glands are usually found on the outer surface. The collared peccary's lip shows, on the outer surface, simple and sinus hair follicles as well as sebaceous and apocrine sweat glands. No salivary gland is found on the inner surface, and deep in the connective tissue pacinian corpuscles can be found. The connective tissue is rich in collagen and elastic fibres. The collared peccary's lip may be used not only for food prehension but also functions as a sensitive structure giving tactile input to the central nervous system.     

Anatomicohistological characteristics of the tubular genital organs of the female collared peccary (Tayassu tajacu) from North-eastern Amazon

The present study examines anatomical and histological characteristics of tubular genital organs and its relationships with the reproductive state of 24 wild adult collared peccary (Tayassu tajacu) females. The tunica mucosa of the uterine tube presents a pseudostratified, intermittently ciliated columnar epithelium. The epithelial secretory cells of pregnant females and females in the luteal phase of the oestrous cycle became taller than the ciliated cells and showed abundant apical secretory blebs, whereas secretory cells of females in the follicular phase showed abundant mucous secretory activity (periodic acid-Schiff positive cells). The uterus is composed of two narrow and convoluted uterine horns, separated by the velum uteri, a small uterine body and a long and muscular cervix. The endometrial lining of both uterine horns and body is a monostratified, columnar ciliated epithelium. Pregnant females and females in luteal phase showed a more developed hyperplasia of the endometrial simple tubular glands than females in the follicular phase. The cervix presents interdigitated rows of mucosal prominences that project into the lumen, structures similar to pulvini cervicali, occluding the cervical canal. In pregnant females, the endocervical canal was filled by a viscous cervical secretion. Females in follicular phase presented a thicker vaginal epithelium than pregnant females and females in luteal phase. The present study suggests that the collared peccary female showed different histological features of the uterine tubes, uterus and vagina in accordance with the reproductive state of the females.     

Morphological features of the seminiferous epithelium in cat (Felis catus, L. 1758) testes

The aim of the present study was to assess the changes in the germinal epithelium in cats of different ages. Routine histological staining was applied to perform morphological and stereological examinations. The animals were divided into five groups according to age: under 8 months (n=28), 8-12 months (n=30), 12-36 months (n=33), 3-6 years (n=14) and older than 6 years (n=13). The appearance of the gonads of the males in the first group varied the most. The seminiferous tubules of the youngest cats consisted of a monolayer of supporting cells and a few spermatogonia. No tubular lumina were present, and the diameters of the seminiferous tubules reached 132.5 microm. We noted the typical arrangement of gametogenic cells with a tubule diameter of 191.83 microm in the second group. We observed multilayer germinal epithelia with the most significant production of gametes and a seminiferous tubule diameter of 202.61 microm in the third group. The diameters of the seminiferous tubules of the forth and fifth groups were 193.38 microm and 191.84 microm, respectively. The obtained data revealed that the most intensive morphological diversification of the seminiferous epithelium in cats occurs at about 7-8 months of age. The diameters of seminiferous tubules were highest in the third group of cats, and the activity of spermatogenesis of this group, expressed as the number of sperm per 10 mm(2), was also the most distinctive. The spermatogenesis process was most evident in cats between 12 and 36 months of age, which was also when the sperm concentration was highest per estimated surface.     

Immunohistology of the splenic compartments of the one humped camel (Camelus dromedarius)

The cellular composition of the different splenic compartments is well characterized in several species, but the spleen of the camel has not been studied due to the lack of specific antibodies detecting its leukocyte subsets. Therefore, 5microm frozen sections from 15 camel spleens (0.5-15 years) were studied for acid and alkaline phosphatases and for cross-reaction with antibodies specific for bovine (n=181), swine (n=14) and human (n=6) leukocyte determinants. Fifteen antibodies cross-reacted with camel spleen cells. These included 13 anti-bovine, two anti-human, but no anti-swine antibodies. The lymph follicles mainly consisted of B cells. The germinal centers showed a strong alkaline phosphatase activity. The periarterial lymphatic sheath harbored T lymphocytes. The marginal zone contained gammadelta T cells, CD45R0+, MHC class II DR+, CD44+, IL-A 24+ cells and few macrophages. The red pulp contained B, T, MHC class II DR+, IL-A24+ and gammadelta T cells and few macrophages. The periarterial macrophage sheaths contained many more macrophages than the marginal zone, so they may play a central role in the phagocytosis of the blood born particles. The alkaline phosphatase probably labeled activated B cells, but in contrast to other species no positive cells were found in the marginal zone. In general, lymphocyte compartmentalization in the camel spleen is similar to that in other species except for lower numbers of macrophages and the absence of alkaline phosphatase positive cells in the marginal zone. No age related differences were observed in the splenic compartments.     

从江香猪生精上皮周期及睾丸发育的形态学分析

试验旨在探究初情期前后生精上皮周期差异及睾丸发育过程中的形态学变化。通过测定15、30、60和90 d睾丸相关指数，结合睾丸组织形态学特征，判断香猪初情期，划分从江香猪生精上皮周期。结果显示，30 d的睾丸指数较15 d极显著升高（P<0.01），睾丸重、长轴及短轴的增长率分别为298.05%、66.42%和65.45%，60和90 d两个阶段睾丸重增长率相对稳定。形态学观察表明，从江香猪30 d时生精小管出现游离精子，完成第一次生精并进入初情期；与15 d相比，30 d生精小管面积和生精上皮厚度极显著增加（P<0.01），增长率分别为136.12%和40.19%，在60和90 d均处于稳定增长状态。睾丸细胞数统计显示，日龄增加不影响支持细胞（setoli cells，SC）数量（P>0.05），而30 d生殖细胞数（germ cells，GC）较15 d极显著增加（P<0.01）。相关分析结果发现，生殖细胞数量增加与生精小管面积增大、生精上皮厚度变化之间呈明显正相关（r=0.994；0.96）。根据生殖细胞组合形式差异，将初情期前后生精上皮分为3和8个阶段。初情期前生殖细胞以第一次减数分裂前期为主，A、B型精原细胞、SC、初级精母细胞（primary spermatocyte，Ps）、前细线期（preleptotene，PI）、细线期（leptotene，L）等生殖细胞在初情期前后生精上皮中均存在，而圆形精子（round spermatids，R）、延伸精子（elongating spermatid，E）、精子细胞（spermatozoa，S）仅存在于初情期后的生精上皮。本研究结果表明，从江香猪30 d初情，睾丸发育以生殖细胞和生精小管面积的迅速增加为主，该结果对从江香猪早熟性状挖掘、种猪选育及开发利用等有重要的指导意义。     

Relationship of absolute numbers of Sertoli cells to testicular size and spermatogenesis in young beef bulls

Testes were obtained from 34 Hereford or Angus bulls at about 1.5 yr of age and were used to investigate the relationship between the absolute number of Sertoli cells vs testicular size and daily spermatozoal production (DSP). Quantitative determination of DSP was based upon enumeration of elongated spermatids in testicular homogenates. The ratio of step 8 spermatids to Sertoli cells (S:SC) was established by direct counts of these cells in each of 20 round stage VIII seminiferous tubular cross sections for each bull. The number of Sertoli cells per paired testes was calculated as (total spermatids divided by S:SC)/.394, where total spermatids equalled the number of homogenization-resistant spermatids. The factor of .394 adjusted for the fact that the latter cells are present for only 39.4% of the spermatogenic cycle. All data were subjected to simple linear and second-order regression analyses. A positive linear relationship (P less than .005) was found between testicular weight (Y, in grams) and the absolute number of Sertoli cells per paired testes (X, in billions), which was characterized by the equation Y = 315.2 + 10.74X and a coefficient of correlation (r) of .56 (P less than .01). A similar relationship was observed between DSP (Y, in billions) and Sertoli cell numbers (X, in billions). This was characterized by the equation Y = 1.36 + .222X (P less than .005) and a coefficient of correlation of .70 (P less than .01). Daily sperm production was unrelated to the S:SC ratio (P greater than .05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Relationship between serum sex hormone concentrations and histology of seminiferous tubules of captured baleen whales in the Western North Pacific during the feeding season

The present study was conducted to obtain new information on relationships among serum testosterone (T), estradiol-17 beta (E(2)), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) concentrations and histology of seminiferous tubules in captured common minke and Bryde's whales during the feeding season. Blood samples and testes were collected from common minke (n=39 for blood samples, n=15 for testes) and Bryde's (n=14 for blood samples, n=7 for testes) whales captured from May 2001 to August 2001 in the Western North Pacific. Serum T concentrations, in 35.9% of the common minke and 57.1% of Bryde's whales, were below the detection limit (< 2.5 pg/ml). There were no significant differences in the serum concentrations of E(2), FSH, and LH among immature, mature common minke and Bryde's whales except that LH levels of immature Bryde's whales was higher than those of common minke whales. In most seminiferous tubules of mature whales, only a single-layer of spermatogonia was observed. However, spermatozoa were observed in seminiferous tubules in 2/13 of mature common minke and 4/4 of mature Bryde's whales with the low or undetectable T levels. These results indicate that the low serum T concentrations reflect the inactivity of spermatogenesis in both baleen whales, and that it is not possible to assess gonadal activity in either common minke or Bryde's whales using serum sex hormone concentrations during the feeding season.     

Genotyping of Clostridium perfringens isolated from domestic and exotic ruminants and swine

Clostridium perfringens types A, B, C, D and E are known to cause severe enteritis/enterotoxaemia and diseases (especially caused by type A) belonging to the gas oedema complex in many species. Samples from the small intestine as well as faeces of domestic and exotic animals suffering from enterotoxaemic signs or having died within days after first occurance of toxaemia were submitted for typing C. perfringens toxovars by multiplex PCR. The following species have been investigated: domestic sheep (Ovis ammon; n = 10), domestic goat (Capra aegagrus hircus; n = 26), Japanese serow (Capricornis sumatraensis; n = 4), lechwe waterbuck (Hydrotragus leche; n = 1), blackbuck (Antilope cervicapra; n = 1), European reindeer (Rangifer tarandus tarandus; n = 4), domestic swine (Sus scrofa; n = 52), and collared peccary (Tayassu albirostris; n = 1). Interestingly, the predominant C. perfringens toxovar in domestic sheep was type A. This toxovar could also be diagnosed in all reindeer, in three Japanese serows, one lechwe waterbuck and most pigs (n = 47), the majority of those being at suckling age. Type D was the most prevalent toxovar (n = 18) in domestic goats, but also types A and E could be identified as pathogens in this species. Type C could only be found in domestic swine (n = 5) and in one case of clostridiosis in a Japanese serow. Two cases of enterotoxaemia in goats, one case in reindeer, and a single case in blackbuck and collared peccary were caused by C. perfringens type E. Genotyping of C. perfringens is recommended before starting vaccination programmes as it could be shown, that the importance of specific toxovars has been underestimated in specific species and/or age groups.     

Molecular detection of Mycoplasma suis in captive white-lipped peccaries (Tayassu pecari) and wild boars (Sus scrofa) in Brazil

Mycoplasma suis, the etiological agent of swine hemoplasmosis, is an epicellular bacterium that adheres to the surface of pig erythrocytes leading to deformations of the target cells. Little is known about the occurrence of M. suis in wild swine populations around the world, its economic impact on swine herds, and the risk of human infection. The aim of this study was to investigate, by quantitative real-time PCR (qPCR) based on the 16S rRNA gene, the occurrence of M. suis in a captive population of white-lipped peccaries (100 Tayassu pecari) and in free-living wild boars (14 Sus scrofa) in Brazil. None of the white-lipped peccaries were positive for M. suis, whereas seven (50%) wild boars were positive in qPCR assays. The quantification of M. suis-16S rRNA copies/μL ranged from 1.42 × 10° to 3.906 × 10¹ in positive animals, indicating a low bacteremia and a chronic carrier status in free-living wild boars. In conclusion, M. suis might be a non-frequent pathogen in wild suids maintained in captivity. Despite the low bacteremia, the prevalence of M. suis in wild boar population in Brazil seems to be high.     

Scrotal circumference, seminal characteristics, and testicular lesions of yearling Angus bulls

The effect of age and body weight on scrotal circumference (SC), the effect of SC on percentage of sperm abnormalities and seminal characteristics, and the relationship of SC with testicular weight, epididymidal weight, degree of germinal epithelial loss (DGEL), and percentage of tubules graded 4 or greater (G4+) were studied in 37 Angus bulls. All bulls were from one herd and were examined at monthly intervals, during a 140-day weight gain test starting when they were 11 months old. The study was terminated when the bulls were slaughtered at 14 months of age. As age and body weight increased, SC increased (P less than 0.001). The incidence of sperm abnormalities decreased (P less than 0.001) as SC increased; however, seminal characteristics remained poor in bulls with SC less than or equal to 32 cm. Pathologic changes in 600 cross sections of seminiferous tubules from each bull were classified into 9 grades. The DGEL per 100 tubules was calculated by assigning a value to each grade according to the severity of loss of germinal epithelium. Tubules classified as G4+ were devoid of germinal cells and provided an index of irreversible loss of germinal epithelium. The SC was correlated positively with testicular weight (r = 0.91, P less than 0.001) and epididymal weight (r = 0.59, P less than 0.001) and negatively with DGEL (r = -0.48, P less than 0.01) and G4+ (r = -0.44, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

黄鳝性逆转过程中性腺形态学初步观察

试验通过对性逆转过程中雌、雄鳝以及雌雄间体鳝的性腺的形态学进行观察 ,结果显示 ,雌鳝性腺大部分含肉眼可见的卵粒 ,但各时期卵巢的卵粒大小不一。雌雄间性阶段黄鳝性腺肉眼仅见不同形态的卵粒 ,部分卵粒极少 ;组织切片既可观察到卵母细胞 ,还可发现结缔组织纵隔和在纵隔上形成的管状结构的早期精细管 ;而雄鳝阶段黄鳝性腺多呈乳白色带有黑色斑点 ,带有较多且大的黑色斑点性腺可能是卵母细胞退化凋亡痕迹 ,其切面中有较稀疏精母细胞 ,可能属早期的精巢 ;乳白色性腺中黑色斑点极少 ,精母细胞相对较密集 ,可能是成熟期的精巢。试验表明黄鳝“性逆转”在形态学上具有明显的阶段性特征     

Classification of the spermatogenic cycle,seasonal changes of seminiferous tubule morphology and estimation of the breeding season of the large Japanese field mouse (Apodemus speciosus) in Toyama and Aomori prefectures, Japan

The large Japanese field mouse, Apodemus speciosus, is a potential indicator of environmental stress, but this function has not been confirmed by histological studies. Since environmental stress affects the reproductive function of mice, we determined the reproductive characteristics of this species at two locations: Toyama (36°35ʹN, 137°24ʹE) and Aomori (40°35ʹN, 140°57ʹE). Mice were captured during May–November (n=119) and July–November (n=146) at these locations, respectively. We classified the breeding season from the numbers of pregnant females and young, in addition to the spermatogenic cycle and seasonal changes in seminiferous tubule morphology of males. Testicular weight was measured, and seminiferous tubule morphology was examined histologically. Fourteen stages were found in the seminiferous epithelium cycle based on acrosome formation and spermatid head morphology. At both locations, the breeding season peaked from late summer to early autumn and possibly in spring. Spermatogenic activity was classified into 4 periods from June to November: resting around June and October–November; resumptive around July; active around August; and degenerative around September. During the resting period, the seminiferous tubules consisted of Sertoli cells, spermatogonia and spermatocytes. Spermatogenesis began during the resumptive period, and spermatids were observed. During the active period, active spermatogenesis and a broad lumen were observed. During the degenerative period, spermatogenesis ended, and Sertoli cells, spermatogonia, spermatocytes and degenerating exfoliated round spermatids were observed. This study provides scientific information about the testicular histopathological evaluations of the large Japanese field mouse for its use as an index species of environmental pollution.     

Pathophysiology of small testes in beef bulls: relationship between scrotal circumference, histopathologic features of testes and epididymides, seminal characteristics, and endocrine profiles

Tissue sections from testes and epididymides obtained from 17 young beef bulls with scrotal circumference (SC) between 27 and 40.5 cm were studied to determine whether small testes were a manifestation of lesions or a result of less, but otherwise normal, seminiferous epithelium. The SC correlated negatively with the estimates of germinal epithelial loss and positively with seminiferous epithelial area. Four bulls with SC less than 30 cm had severe lesions in their testes. Hypoplastic tubules were characterized by Sertoli's cells only with no evidence of germinal cells. Loss of germinal cells, leaving vacuolated epithelium and atrophy, were observed in degenerated tubules. Hyperplasia of Leydig's cells was observed in the vicinity of Sertoli's cell-only tubules, resulting either from degeneration or hypoplasia, and atrophy of Leydig's cells was associated with tubules devoid of Sertoli's cells. These findings indicated that Sertoli's cells may produce a factor(s) required for maintenance and regulation of Leydig's cell function. Epididymal epithelium, especially in the head, had regressed in bulls with hypoplastic and degenerative changes in their testes. Decreased sperm concentration and motility and an increased frequency of morphologic defects were observed in the 4 bulls with testicular lesions and regressed epididymal epithelium. Blood plasma profiles of cortisol, follicle-stimulating hormone, luteinizing hormone, and testosterone were determined in the 4 bulls with SC less than 30 cm and 10 of the 13 bulls with SC greater than 30 cm. There were no statistically significant (P greater than 0.1) differences in the responses to exogenous gonadotropin-releasing hormone or base-line patterns of blood plasma follicle-stimulating hormone and luteinizing hormone between the 2 groups. However, in the bulls with SC less than 30 cm, the mean concentration of testosterone was lower, whether spontaneous (P less than 0.05) or exogenous gonadotropin-releasing hormone induced (P less than 0.1). The fact that these bulls were not deficient in gonadotropins indicated that Leydig's cell function was impaired by local factors, either the factors that caused the tubular damage or those consequent to the tubular damage.     

Cycle of the seminiferous epithelium in the Java fruit bat (Pteropus vampyrus) and the Japanese lesser horseshoe bat (Rhinolophus cornutus)

The cycle of the seminiferous epithelium in the Java fruit bat, Pteropus vampyrus, and the Japanese lesser horseshoe bat, Rhinolophus cornutus, was investigated by light microscopy and the characteristics of spermiogenesis were compared between these two species. In the Java fruit bat, the cycle of the seminiferous epithelium was divided into 11 stages and developing spermatids were subdivided into 13 steps. While in the Japanese lesser horseshoe bat, the cycle of the seminiferous epithelium was divided into 10 stages and developing spermatids were subdivided into 13 steps. Excepting slight morphological differences, the characteristics of acrosomal formation in both species were almost similar with each other. In the Java fruit bat after stage VII, the acrosome gradually elongated, flattened and finally became scoop-like in shape. In the Japanese lesser horseshoe bat after stage VIII, the acrosome elongated, flattened and then slightly shortened. Before spermiation, the acrosome became long spatula-like in shape. The elongation and flattening of spermatids in these two species were similar to those in insectivores. The finding may reflect the fact that the order Chiroptera is phylogenetically close to the order Insectivora.