Atoxoplasma spp. infection in captive canaries (Serinus canaria)

Clinical signs, histopathological and ultrastructural findings associated with Atoxoplasma spp. natural infection in captive canaries (Serinus canaria) are described. Intracytoplasmic Atoxoplasma-like protozoa were found in the liver and lung. In the liver, protozoa were found in hepatocytes and Kupffer's cells and were associated with granulomatous hepatitis and a marked bile duct hyperplasia. An usual finding was the presence of infected mononuclear cells adhered to the endothelium of the blood vessels in lung. The diagnosis was confirmed by ultrastructural examination of reprocessed paraffin-embedded tissues.     

Increasing incidence of megabacteriosis in canaries (Serinus canarius domesticus)

A total of 312 post-mortem examinations of 178 canaries (Serinus canarius domesticus), 40 parakeets (Melopsittacus undulatus, Nymphicus hollandicus) and 94 parrots (Amazona aestiva, Psitaccus erithacus) were conducted at the Birds and Rabbits Service of the University of Liège, Belgium. After a detailed gross examination, tissue samples were collected for virological and/or bacteriological and/or parasitological examination to complete the diagnosis. In all cases, a microscopic examination of the proventricular mucus layer was undertaken for the detection of the anamorphic ascomycetous yeast Macrorhabdus ornithogaster, which causes the non-zoonotic but important disease in cage birds known as megabacteriosis. At the time of death, megabacteriosis was diagnosed respectively in 28% of canaries and 22.5% of budgerigars (P value for Fisher's exact test=0.5576), but was not diagnosed in parrots (P value for Fisher's exact test <0.0001). The incidence of megabacteriosis significantly increases along the years (P value for chi2 test <0.0001, Cramer's coefficient=0.3405). The most common gross lesions seen at necropsy of the 59 megabacteriosis cases was proventricular dilatation (86.1%). All the birds diagnosed as typical megabacteriosis cases were free of Salmonella spp. infections and of any parasitic infections. Four megabacteriosis cases (three canaries, one parakeet) were not included in statistical analysis as salmonellosis, pseudotuberculosis, coccidiosis and chlamydophilosis were diagnosed concomitantly in these birds. With the exception of megabacteriosis, the most frequent causes of death were protozoan (coccidiosis, lankesterellosis) infections (18.4%) and salmonellosis (17.1%) in canaries, and psittacosis (31.5%) and viral hepatitis (26.3%) in parakeets. In parrots, the most common causes of death were psittacosis (28.6%) and aspergillosis (28.5%).     

Mucor ramosissimus associated with feather loss in canaries (Serinus canarius)

Three canaries showing feather loss on legs, dorsum, neck, and head, and hyperkeratosis on the feet were sacrificed because of their poor corporal condition and submitted to the Unit of Histology and Anatomic Pathology at the Veterinary School of Las Palmas de Gran Canaria. Histologically, skin revealed pronounced epidermal and follicular infundibular hyperplasia associated with orthokeratotic hyperkeratosis. Numerous fungal spores were observed on the stratum corneum of the epidermis and within feather follicles, associated with destruction of the feathers. This fungus was identified as Mucor ramosissimus. To the best of authors' knowledge, this is the first report of dermatitis and feather loss associated with Mucor ramosissimus, not only in canaries but also in birds.     

Energy and protein allowances and requirements in stallions during the breeding season, comparing different nutritional systems

This study was conducted to estimate the nutritional value of diets given to stallions of different breeds during the reproductive season, and comparing allowances with requirements. The systems compared were the French INRA, the 1989 NRC, and the 2007 NRC. Data on reproductive activity, daily exercise, BW, BCS, feed intake, and feed composition during 4 mo (from March to June) were recorded on 12 stallions used for commercial AI programs. Stallions belonged to 3 different breeds: Italian Haflinger (IH, n=4), Holstein (HOL, n=4), and Italian Heavy Draft horse (IHDH, n=4). Data recorded were used to estimate the actual energy and protein intakes and theoretical requirements of the stallions using the aforementioned systems. A deviation index [DI = (intake - requirement)/intake × -1] was calculated to allow a comparison among methods as a proportion of under- or overestimates of theoretical requirements. All data were statistically analyzed with a mixed model for repeated measurements. The reproductive activity of the stallions was affected by month (less in March and greater in subsequent months; P<0.05). Daily exercise was generally low during the middle breeding season, and the intensity and kinds of exercise differed according to the breeds. Changes of BW and BCS of the stallions were not statistically significant (P=0.69 and P=0.17, respectively) during the experimental period, and therefore diets could be considered balanced to support all animal needs. However, the energy and protein allowances were not always consistent with the theoretical requirements considering all 3 nutritional systems. Energy and protein INRA recommendations showed, on average, +0.90 and +0.27 greater DI than actual intakes, respectively, for IH and HOL stallions, whereas the theoretical requirements were much closer to allowances for the IHDH stallions (DI close to 0). The 1989 NRC energy and protein recommendations, respectively, were +0.67 and +0.87 greater than intake for IH, +0.28 and +0.43 greater for HOL, and only +0.06 and +0.17 greater for IHDH stallions. The 2007 NRC energy and protein recommendations, respectively, were +0.70 and +0.52 greater for IH, +0.33 and +0.17 greater for HOL, and +0.52 and +0.49 greater for IHDH than actual intakes. Therefore, all systems overestimated the requirements of the stallion, particularly in lighter breeds. Further studies to validate requirements for breeding stallions of different sizes are recommended.     

A retrospective description of a highly pathogenic avian influenza A virus (H7N1/Carduelis/Germany/72) in a free-living siskin (Carduelis spinus Linnaeus, 1758) and its accidental transmission to yellow canaries (Serinus canaria Linnaeus, 1758)

A haemagglutinating virus was isolated in summer 1972 from a single free-living siskin (Carduelis spinus Linnaeus, 1758) in embryonated chicken eggs. Additional cases of morbidity or mortality were not observed in the area were the sick siskin was found. The virus was characterized as an avian influenza A virus of the subtype H7N1 and designated H7N1/Carduelis/Germany/72. The virus induced following experimental inoculation of chicken embryos a high rate mortality (mean death time approximately 24 hours), formed plaques in chicken embryo fibroblast cultures without addition of trypsin and has an intracerebral pathogenicity index (ICPI) of 1.80. Therefore, this virus is considered as a highly pathogenic avian influenza A virus. Canaries (Serinus canarius Linnaeus, 1758), that were housed in the same room with the siskin were accidentially exposed by contact to the sick siskin which resulted in virus transmission followed by conjunctivitis, apathy, anorexia and a high rate mortality.     

Genomic characterization of the first oral avian papillomavirus in a colony of breeding canaries (<Emphasis Type="Italic">Serinus canaria</Emphasis>)

Papillomaviruses are non-enveloped, DNA viruses that infect skin and mucosa of a wide variety of vertebrates, causing neoplasias or simply persisting asymptomatically. Avian papillomaviruses, with six fully sequenced genomes, are the second most studied group after mammalian papillomaviruses. In this study, we describe the first oral avian papillomavirus, detected in the tongue of a dead Yorkshire canary (Serinus canaria) and in oral swabs of the same bird and other two live canaries from an aviary in Madrid, Spain. Its genome is 8,071 bp and presents the canonical papillomavirus architecture with six early (E6, E7, E1, E9, E2, E4) and two late open reading frames (L1 and L2) and a long control region between L1 and E6. This new avian papillomavirus L1 gene shares a 64% pairwise identity with FcPV1 L1, so it has been classified as a new species (ScPV1) within the Ethapapillomavirus genus. Although the canary died after showing breathing problems, there is no evidence that the papillomavirus caused those symptoms so it could be part of the oral microbiota of the birds. Hence, future investigations are needed to evaluate the clinical relevance of the virus.     

Ovarian and testicular function in the blue fox (Alopex lagopus) after oral administration of fenchlorphos during the breeding season

The possible effect of fenchlorphos, 0-0-dimethy1-0-(2.4.5-trichlorophenyl) phosphorothioate, upon the reproductive endocrinology in blue foxes (Alopex lagopus) was investigated. Five females were administered fenchlorphos orally at a dose of 100 mg/kg daily from 10 days before oestrus and up to the 21st day of gestation. This dose represents the therapeutic dose for the treatment of sarcoptic mange. Blood samples were collected for the analyses of progesterone, oestradiol-17β and luteinizing hormone (LH) in plasma. The vixens were ovario-hysterectomized on day 23, except 1 animal in the control group which was operated on day 17. Additionally, sperm quality and mating performance in 3 male blue foxes, which were administered 100 mg/kg fenchlorphos daily during the first 3 weeks of the mating season, were examined.Pregnancy was recorded in 2 medicated and 4 control animals. No pathological changes were observed in the uterus and the ovaries. The plasma concentrations of the hormones were similar to those obtained from the control group. No evidence of any disturbances concerning spermatogenesis in the males was observed. However, their libido appeared to be reduced. None of the males achieved a mating during and after the period of medication.     

Immunolocalization of steroidogenic enzymes and their expression during the breeding season in the testes of wild raccoon dogs (Nyctereutes procyonoides)

The objective of this study was to investigate immunolocalization of steroidogenic enzymes 3βHSD, P450c17 and P450arom and their expression during the breeding season in wild male raccoon dogs. The testicular weight, size and seminiferous tubule diameters were measured, and histological and immunohistochemical observations of testes were performed. The messenger RNA expression (mRNA) of 3βHSD, P450c17 and P450arom was measured in the testes during the breeding season. 3βHSD was found in Leydig cells during the breeding and non‐breeding seasons with more intense staining in the breeding season. P450c17 was identified in Leydig cells and spermatids in the breeding season, whereas it was present only in Leydig cells in the non‐breeding season. The localization of P450arom changed seasonally: no immunostaining in the non‐breeding season; more extensive immunostaining in Leydig cells, Sertoli cells and elongating spermatids in the breeding season. In addition, 3βHSD, P450c17 and P450arom mRNA were also expressed in the testes during the breeding season. These results suggested that seasonal changes in testicular weight, size and seminiferous tubule diameter in the wild raccoon dog were correlated with spermatogenesis and immunoreactivity of steroidogenic enzymes and that steroidogenic enzymes may play an important role in the spermatogenesis and testicular recrudescence and regression process.     

Spermatozoa morphology during the breeding season in Thoroughbred stallions in Japan

The morphology of spermatozoa of modern Thoroughbred stallions in Japan was investigated during the breeding season. A total of 299 semen samples were collected from the penises of 16 stallions immediately after service. The rate of abnormalities in sperm heads and tails, spermatozoa with cytoplasmic droplets and slides with medusa cells to total observed slides in each stallion were 3.9 +/- 2.1%, 11.5 +/- 5.9%, 2.4 +/- 2.6% and 20.1%, respectively. The values for the area, length, width and aspect ratio of the stallion sperm head were 12.54 +/- 1.34 microm(2), 5.93 +/- 0.40 microm, 2.69 +/- 0.21 microm and 0.46 +/- 0.05, respectively. With the exception of medusa cells, the features were significantly different among the stallions (P<0.05).     

Immunolocalization of inhibin/activin subunit proteins during the breeding season in testes and scented glands of muskrats (Ondatra zibethicus)

The objective of this study was to investigate the cellular immunolocalization of inhibin a and inhibin/activin (β(A) and β(B)) subunits in the muskrat testes and scented glands during the breeding season. Inhibin α and inhibin/activin (β(A) and β(B)) subunits were expressed in Sertoli cells and Leydig cells of testes and glandular cells of scented glands, respectively. Also, positive signals of inhibin α and inhibin/activin (β(A) and β(B)) subunits by Western blotting were both observed in testicular and scented glandular tissues. These results suggested that the testes and scented glands of the muskrats had the ability to synthesize inhibins and activins and that activins and inhibins might play an important role in testicular and scented glandular function in muskrats.     

Histological and immunohistochemical investigations of ovarian interstitial glands during non‐breeding season in camels (Camelus dromedarius)

The aim of this was to investigate the histology and immunohistochemistry of interstitial glands during non‐breeding season in camel ovaries. A total of 21 mature, non‐pregnant and apparently healthy camels aged between 8 and 12 years were slaughtered. The ovaries were removed within 15 min, cleaned from adipose tissue, weighted and examined grossly. The histological preparation was made, and then, the blocks were cut at 3–5 microns thickness and stained by H&E for histological examinations. Moreover, some sections were stained with Sudan Black for lipid detection. Immunohistochemical analysis of paraffin‐embedded ovarian tissues was performed to detect the localization of S‐100, vimentin, progesterone receptors (PR) and oestrogen receptors (ER). Immunoreactive signals were detected using UltraVision Detection System. The results revealed that the interstitial glands were located in the cortical region and they were arranged in various arrangements either single, in couple or in groups rich in lipid droplet. All interstitial gland arrangements were enclosed by connective tissue capsules containing fibroblasts and collagenous fibres separated them from the surrounding ovarian structures. Both interstitial glands and their surrounding CT were penetrated by several blood vessels. There was a strong immunoreactive signal for S‐100 in the nuclei of interstitial cells, and no signals were detected either in cells of the interstitial glands or their connective tissue with PR. We could conclude that the interstitial gland is distinct in ovary of camel and further studies are needed to elucidate its rule in steroid synthesis.     

Reproductive characteristics of stallions during the breeding and non-breeding season in a tropical region

The objective of this study was to investigate reproductive characteristics of stallions at a tropical zone in the breeding and non-breeding seasons. The following parameters were assessed: testicular volume; semen quality; and serum concentrations of LH, FSH, and testosterone; in addition to the percentages of germ cells and proportions of germ cells/Sertoli cells by testicular cytology in stallions. Semen was collected from eight adult stallions twice a week during a 12-week period in both seasons (6?weeks before and 6?weeks after the summer and winter solstices). Jugular blood samples were collected periodically for hormone analysis by radioimmunoassay during the same periods. Testicular measures and cytological samples were taken at the end of each period. Mean concentration of testosterone was significantly higher (P?=?0.04) during the breeding season and the proportion of Sertoli cells/100 germ cells in cytological smears was significantly lower during the breeding season (P?=?0.0001). Effects of season were not significant either for testicular volume or for any semen parameter (P?>?0.05). Seasonal changes in the mean concentrations of LH and FSH were not observed (P?>?0.05). There were also no significant differences in the mean percentages of germ cell types between both seasons (P?>?0.05). Lack of seasonal differences in the testicular volume and semen parameters of tropical stallions are probably due to the small variation in duration of natural light between the observed periods, slightly under 3?h.     

Androgen concentration in the blood and spermatogenic function of tom cats during the breeding season

In order to better understand androgen secretion in the tom cat during the breeding season, observations of diurnal changes in peripheral blood testosterone (T) levels, were made and the relation between androgen levels (androstenedione (A), 5 alpha-dihydrotestosterone (DHT). T) in testicular and peripheral vein blood was borne. Histologic examinations of the testis were also performed to investigate spermatogenic function. The 9 tom cats used in these studies were 2-3 years old, weighed 3.5-4.0 kg, and were raised in a room under natural lighting. As a result, diurnal peripheral blood T levels in the tom cat fluctuated greatly according to each individual, but since no definite trend could be identified, secretion was determined to be episodic. Although fairly large differences in the 3 types of androgen were observed in testicular vein blood depending on the individual animal, levels on the left and right were almost equal. Moreover, a correlation was found between the testicular and peripheral vein blood concentrations of the 3 androgens (A: p less than 0.01; DHT: p less than 0.05; T: p less than 0.01). Therefore, secretion of testicular androgen can be inferred by measuring peripheral blood androgen levels. Testicular histological examination revealed active spermatogenesis in all of the cats, and no significant inter individual differences were detected in either seminiferous tubule diameters or any of the various germ cells.     

Treatment of male goats with equine chorionic gonadotrophin during the non-breeding season does not affect their sperm characteristics during the subsequent breeding season

Tropical Animal Health and Production - Equine chorionic gonadotrophin (eCG) is a hormone having FSH/LH effects. It can be used to enhance sperm quality in male goats (bucks) during the...     

Male-to-female aggression in cage-housed common pheasants (Phasianus colchicus) during the breeding season was not related to male plasma testosterone level

1. The aim of this study was to investigate if male-to-female aggression of common pheasants in the course of the breeding season was related to the concentration of plasma testosterone and/or other biochemical plasma indicators in male pheasants housed in breeding cages. The influence of season on the concentration of testosterone and biochemical indicators was also investigated.

2. Males were divided into non-aggressive and aggressive groups during the breeding season based on ethological evaluation. At the beginning, in the middle and at the end of the breeding season, a blood sample was taken from all males on the same day and the concentration of selected biochemical indicators and the total circulating testosterone in the plasma were determined.

3. Male-to-female aggression during the breeding season of pheasants was not influenced by the total plasma testosterone of males.

4. The concentration of total plasma testosterone in males decreased gradually during the breeding season.

5. Male-to-female aggression of pheasants did not have a significant effect on any of the assessed biochemical indicators.

6. The influence of the breeding season affected the activities of alanine aminotransferase and aspartate aminotransferase as well as the concentrations of glucose, magnesium, potassium and chloride in the blood plasma of cage-housed male pheasants.