Differential molecular identification of Taeniid spp. and Sarcocystis spp. cysts isolated from infected pigs and cattle

In the present work, the species-specific identification of Taeniid spp. cysticerci and sarcocystis cysts isolated from infected pigs and cattle was achieved by PCR. In particular: (i) multiplex-PCR derived from HDP2 DNA fragment, specific for Taenia saginata/Taenia solium; (ii) PCRs and PCR-RFLPs of the rDNA internal transcribed spacers 1 and 2 (ITS1 and ITS2) for the differential diagnosis of taeniids; (iii) PCR derived from the 18S rRNA gene and sequencing, specific for Sarcoystis spp. The combined application of these three PCR protocols provided an unequivocally specific diagnosis of T. saginata, T. solium, T. hydatigena, Sarcocystis hominis and Sarcocystis suihominis, and may have practical application in the identification of calcified degenerating or morphologically dubious cysts, for example in the slaughter house situation or in human biopsy samples.     

Increased incidence of DNA amplification in follicular than in uterine and blood samples indicates possible tropism of Neospora caninum to the ovarian follicle

This study evaluated the presence of Neospora caninum in ovarian follicle aspirates and uterine flushes obtained from N. caninum seropositive dairy cows. Ninety-two cows that aborted within the previous 90 days were sampled to determine the presence of antibodies against N. caninum. Thirteen seropositive cows were chosen for collection of blood leukocytes, uterine flushes (UF; n=12) and follicular aspirates (OPU; n=13). Samples were centrifuged and the cellular sediment from the follicular fluid, uterine flushes and blood leukocytes were used for DNA extraction and PCR. Follicular aspirates had the highest frequency of DNA amplification for N. caninum (p<0.05, 92.3%; 12/13). Whereas uterine (4/12) and blood leukocyte (5/13) samples had similar (p>0.05) rate of positive results. Nonetheless, there was no agreement between blood leukocytes and follicular samples taken from the same animal (Cohen Kappa=-0.16). Similarly, blood leukocytes and uterine results had moderate agreement between them (Cohen Kappa=0.47). This study indicates that N. caninum is present in the ovarian follicle and uterus of seropositive cows, suggesting a possible risk of neosporosis transmission between females during oocyte and embryo collection and transfer. Hence, precautions should be taken to minimize the risk of N. caninum transmission. Furthermore, the high incidence of positive results in follicle samples, that exceeded that of their paired blood leukocytes, suggests a possible tropism of N. caninum for the ovarian follicle.     

Antioxidant profile of cataractous English Cocker Spaniels

Cataracts have been attributed to oxidative injury in proteins and lipids. Primary defenses that directly protect the lens against oxidative damage include small molecule antioxidants (vitamin C, vitamin E, glutathione and carotenoids) and antioxidant enzymes (superoxide dismutase, catalase, and the glutathione enzyme systems – glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase). In humans, low plasmatic levels of vitamin C, vitamin E and carotenoids have been associated with a high risk of senile cataracts. Dogs are more prone to develop cataracts. A decrease in antioxidant defenses could be responsible for increased lens oxidation and cataract development. In this study we report the levels of erythrocytic enzymatic antioxidants (superoxide dismutase, catalase, glutathione peroxidase and glucose-6-phosphate dehydrogenase) and plasma vitamin C as well as malondialdehyde, in normal and cataractous English Cocker Spaniel dogs. Plasma vitamin C levels were consistently lower in cataractous dogs (20.17 μ m  ± 8.2 μ m ) when compared with normal dogs (24.1 μ m  ± 9.4 μ m ). These results indicate a possibly decreased synthesis in vitamin C, leading to lower aqueous humor levels of this vitamin. Considering that vitamin C levels in the aqueous humor may be responsible for lens antioxidant maintenance, and that these levels are obtained from plasma secretion through the ciliary epithelium, decreased plasma levels may indicate a decrease in the antioxidant capacity of the aqueous humor.     

Putative metronidazole neurotoxicosis in a cat

A presumptive case of metronidazole toxicity in a 3.4-kg adult cat is described. The cat had been treated for suspected inflammatory bowel disease with an anti-inflammatory dose of prednisone and metronidazole (73.5-147 mg/kg PO q24h) for approximately 40 days prior to presentation. Clinical signs were primarily related to the central nervous system, including acute tetraparesis, unresponsiveness, tremors, and vocalization. The patient was euthanatized after 12 days of supportive care. Necropsy revealed no significant macroscopic lesions. Histologic evaluation revealed multifocal, fairly well-demarcated foci of necrosis in the brainstem, extending from the diencephalon to the medulla oblongata. To our knowledge, this is the first report to document histologic lesions associated with metronidazole administration in a cat.     

Suspected intestinal torsion in a blacktip reef shark (Carcharhinus melanopterus).

A blacktip reef shark (Carcharhinus melanopterus) with a history of recurrent eversion or prolapse of the valvular intestine, arrived at the Steinhart Aquarium in June 1996 and was placed in a mixed species shark display. The eversion soon reappeared, and the animal became thin and anorexic. The everted portion of the intestine was bitten by another shark and became infected. Treatment included force-feeding, manual reduction of the eversion, hydrocortisone suppositories held in place with purse-string sutures, and injections of enrofloxacin. All treatments ultimately failed, and the animal died in March 1997. Necropsy revealed that the intestine had separated into two segments at the distal portion of the pyloric stomach (duodenum); both ends were scarred and sealed off. It is suggested that a torsion (twisting along the long axis) of the intestine was responsible for the condition.     

First detection of spring viraemia of carp virus in common carp (Cyprinus carpio L.) affected by a septicaemic disease in Mexico

Spring viraemia of carp (SVC) is an infectious disease responsible for severe economic losses for various cyprinid species, particularly common carp (Cyprinus carpio carpio). The causative agent is the SVC virus (SVCV), a member of the Sprivivirus genus, Rhabdoviridae family, and a List 1 pathogen notifiable by the World Organization for Animal Health. This study describes the diagnosis of an SVCV pathogen isolated in October 2015 from wild common carp inhabiting a natural lagoon in central Mexico. While neither an epidemic nor fish mortalities were reported, the collected killed specimens exhibited clinical signs of disease (e.g., exopthalmia, moderate abdominal distension and haemorrhaging, as well as internal haemorrhages and adhesions). Histological results of injuries were consistent with the pathology caused by SVCV. This finding was supported by the isolation of a virus in EPC and BF‐2 cells and subsequent RT‐PCR confirmation of SVCV. The phylogenetic analyses of partial SVCV glycoprotein gene sequences classified the isolates into the Ia genogroup. These findings make this the first report of SVCV detection in Mexico, extending the southern geographical range of SVCV within North America. However, since this pathogen was detected in fish inhabiting a natural body of water without tributaries or effluents, it is difficult to estimate the risk of SVCV for other wild/feral cohabitating cyprinid species in the lagoon. The status of this virus is also unknown for other bodies of water within this region.     

Scales of movement by elk (<Emphasis Type="Italic">Cervus elaphus</Emphasis>) in response to heterogeneity in forage resources and predation risk

Animals may respond to spatial and temporal heterogeneity by altering their movement patterns. The time an animal spends in an area of a given size is termed ȁ8first-passage timeȁ9 and can be used to identify the scales at which different movement processes occur. Using first-passage time and 2-h observations, we identified nested spatial scales representing three movement behaviours for elk (Cervus elaphus) – inactive/resting (moves < 50 m), active/foraging (x̄ = 276.7 m, SD = 56.6), and active/relocating (x̄ = 1628.3 m, SD = 436.6). Our ability to identify inactive behaviour was limited by GPS accuracy. The scale separating relocating and foraging behaviour ranged 550–1650 m across individuals and varied quadratically with the mean patch size of cutover forest in an animal’s home range. We classified path segments into the 3 movement behaviours and related behaviours to local environmental conditions. Elk were likely to be inactive in areas having a low predicted use by wolves (Canis lupus), farther than 50 m from anthropogenic linear clearings, and where microclimatic conditions were cool (high shrub cover and north to east-facing slopes). In contrast, elk were most likely to forage in areas having intermediate levels of herbaceous biomass and low movement costs. Elk were most likely to be relocating when in areas of high wolf use, when close to linear clearings, and in energetically costly situations such as moving upslope. We discuss how elk use of potential foraging habitats may be restricted in this landscape by risks imposed by predators, humans, or both.     

Assessment of blood glutathione peroxidase activity in the dromedary camel

Blood glutathione peroxidase (GSH-Px) levels in 709 normal dromedary camels (442 females and 267 males) were assessed in the Canary Islands. All animals were intensively reared, and three different nutritional systems were evaluated, depending on selenium content of the diet. Mean GSH-Px level in the total population was 288.5+/-157.2 IU x g(-1) Hb. Reference ranges were estimated and enzymatic activities below 51 IU x g(-1) Hb were considered inadequate. GSH-Px activities obtained in females (298.1+/-155.7 IU x g(-1) Hb) were significantly (P = 0.037) higher than in males (272.6+/-157.2 IU x g(-1) Hb). When age groups were compared, only males between 6 and 12 months old exhibited significantly lower mean GSH-Px (P = 0.006) than females. A high correlation (r = 0.88) between serum selenium concentration and blood GSH-Px activity was estimated, and the regression equation was y = 2.5101x + 42.423. Selenium content of the diet above 0.1 mg x kg(-1) DM seems to supply adequate selenium requirements for dromedaries under intensive husbandry.     

Vertical induction of the inclusion body hepatitis/hydropericardium syndrome with fowl adenovirus and chicken anemia virus

The hypothesis that fowl adenovirus (FAV) and chicken anemia virus (CAV), transmitted vertically and simultaneously, induce the inclusion body hepatitis (IBH)/hydropericardium (HP) syndrome in progeny chickens was tested. Thus, 35-wk-old light brown layer breeders, showing absence of antibodies against FAV and variable titers against CAV, were intramuscularly singly infected with the FAV serotype 4 isolate 341 or dually infected with CAV (isolate 10343) and FAV. All hens (groups A [FAV alone], B [FAV + CAV], and C [noninfected]) were clinically healthy throughout the experimental period. Both infectious viruses FAV and CAV were isolated from progenies obtained as early as 5 days after infection of their breeders. Hematocrit, serum proteins, and aspartate-aminotransferase values showed a few statistical differences between the progeny groups. Most of these differences were detected in the progeny chickens of group B. However, almost all values met reference values for the species. The pathologic findings showed that progeny chickens obtained from both singly and dually infected breeders developed macroscopic and histopathologic changes of IBH/HP. The pathologic findings shown by progeny chickens of group A (FAV) were not expected because neither synergism nor prior immunodepression by CAV was concurrent. Chickens of group B (CAV + FAV) also developed IBH/HP. Although not many differences in the evaluated parameters between groups A and B were statistically significant, most pathologic findings of group B indicated a more severe manifestation of the disease. However, because FAV alone did reproduce the syndrome, the results shown by group B would not allow a definitive confirmation of the hypothesis that the association of FAV and CAV is necessary for the successful induction of the IBH/HP syndrome in chickens when transmitted vertically.