Reference ranges for biochemical and haematological values in farmed saltwater crocodile (Crocodylus porosus) yearlings

Objective To determine reference ranges for healthy yearling farmed saltwater crocodiles by performing routine biochemical and haematological laboratory tests on blood samples.
Design A clinico-pathological study.
Procedure Blood samples were collected from 120 healthy yearlings from four Northern Territory crocodile farms and body weight and length were measured. All animals had been fasted for 2 days before sample collection. Routine biochemical analytes were determined on 120 samples and haematological values determined on 30 samples (from one farm).
Results Reference ranges for biochemical and haemato-logical values were determined for farmed yearling saltwater crocodiles in the Northern Territory.
Conclusion The results were comparable with published reference ranges for other crocodilian species. Other published results of haematological values from saltwater crocodiles were from very young (6-week-old) hatchlings and older (2- to 4-year-old) crocodiles. Differences in values were presumed to be caused by age-related factors.     

Pathology of skin diseases in crocodiles

Objective To establish which skin diseases occur in crocodiles, particularly those on farms, to indicate the relative frequency of each particular disease and to provide information on pathogenesis, especially in regard to lesions with two or more pathogens present.
Design A gross and microscopic retrospective (period of 1989 to 1995) and current (1996 to 1997) examination of skin lesions in crocodiles in Queensland and the Northern Territory.
Result Skin lesions were obtained from crocodiles on nine farms, from a group of experimental animals and from one adult found dead in the wild. A total of 203 lesions from 180, mostly young, crocodiles was examined; 119 lesions were from retrospectively examined cases and 84 were recent. The relative frequencies of four presumed primary pathogens in lesions were Dermatophilus s p 28.1 %, fungi 14.8%, poxvirus 3.4% and probable Mycobacterium s p 2.5%. In addition, other bacteria of unknown significance were present in many lesions, and there was one case of presumed Paratrichosoma crocodilus infection. In 32.5% of lesions, multiple pathogens were identified.
Conclusion Dermatophilosis is the most common and probably the most important skin disease of crocodiles in Australia, but it is frequently complicated by concurrent infection with fungi or other microorganisms.     

Salmonella in captive crocodiles (Crocodylus johnstoni and C. porosus)

The prevalence of salmonellas in captive Crocodylus porosus and C. johnstoni was investigated at 2 Northern Territory crocodile farms. Similar proportions of each species at one farm (20.0 and 27.8% for C. porosus and C. johnstoni, respectively) carried salmonellas, but at the other farm there was a significant difference between the 2 species (81.0 and 5.0%, respectively). Procedures for the slaughter of crocodiles and processing of crocodile flesh for human consumption are outlined and discussed from the viewpoint of minimising salmonella contamination. The prevalence of salmonellas on flesh for human consumption (16.0% of carcases) was higher than that reported for beef and mutton, but lower than that for poultry products (Murrell 1986). Serotypes most often isolated from cloacai and faecal swabs were S. cerro, S. singapore, S. enteritidis and S. arizonae. Of the 10 serotypes isolated from processed carcases, S. singapore was most frequently isolated (33.3% of serotypes identified).     

A survey of helminth parasites in backyard flocks in Michigan by litter examination

The prevalence of parasitic infections in backyard flocks was surveyed using litter samples from 74 pens located on 12 farms in central lower Michigan. Eight species of birds were represented. Two methods of litter examination (a sucrose flotation technique and a multiple washing/ZnCl2 flotation) were compared; the sucrose flotation technique was found to be more useful and was used in the survey. The following parasites eggs/oocysts were observed; ascarid-type eggs (in 34 pens from nine farms), Capillaria eggs (in 30 pens from nine farms), Strongyloides eggs (in nine pens from five farms), Syngamus eggs (in five pens from four farms), and coccidial oocysts (in 40 pens from 10 farms). Contamination of litter with ascarid-type eggs, Capillaria eggs, and coccidial oocysts was commonly found, irrespective of bird species. The contamination level in pens with more than one bird species was lower than in pens with a single species. The relatively high contamination rate may be an indication of the risk of parasitic disease in birds that are not raised under controlled conditions in confinement.     

Pharmacokinetics of ceftriaxone in freshwater crocodiles (Crocodylus siamensis) after intramuscular administration at two dosages

One of the major obstacles to the successful treatment of infectious disease in freshwater crocodile species is incorrect dosing of antibiotics. There are few reports on pharmacokinetics and dosage regimens of antimicrobial drugs in crocodiles. The purpose of the present study was to clarify the pharmacokinetic characteristics of ceftriaxone (CEF) in Siamese freshwater crocodiles (Crocodylus siamensis). Freshwater crocodiles, Crocodylus siamensis, in breeding farms were treated with a single intramuscular administration of CEF at two dosages, 12.5 and 25 mg/kg body weight (b.w.). Blood samples were collected at preassigned times up to 168 hr. The plasma concentrations of CEF were measured by a validated method through liquid chromatography tandem-mass spectrometry. CEF plasma concentrations were quantified up to 72 and 96 hr after low- and high-dose administration, respectively. The C_max values of CEF were 24.61 ± 5.15 µg/ml and 26.39 ± 2.81 µg/ml at dosages of 12.5 and 25 mg/kg b.w., respectively. The AUC_last values increased in a dose-dependent fashion. The half-life values were not statistically different between the groups (around 20 hr). The average binding percentage of CEF to plasma protein was 53.78 ± 2.11%. Based on the pharmacokinetic data, susceptibility break-point and the surrogate PK-PD index (T > MIC, 0.2 μg/ml), i.m. administration of CEF at a dose of 12.5 mg/kg b.w. might be appropriate for initiating treatment of susceptible bacterial infections in freshwater crocodiles.     

Husbandry, parasitic and other diseases as factors in the reliability of the enzyme linked immunosorbent assay (ELISA) for detection of trichinellosis in pigs

Serum samples were obtained from pigs originating from specified pathogen-free farms, large industrialised farms and small conventional farms. All animals proved to be free of Trichinella spiralis by a pooled sample digestion method. Careful meat inspection studies on parasitic infections other than trichinellosis, and other inflammatory reactions were recorded and used for subdivision of the animals in different groups. It was concluded that animal husbandry, parasitic infections, or inflammatory reactions have not influenced the mean extinction values of an ELISA for the detection of T. spiralis antibodies, however, the specified pathogen free animals yielded somewhat lower results.     

Echinococcus granulosus in the Northern Territory,Australia: hydatid disease reported in beef cattle from the region

Hydatid disease in beef cattle has been reported to be widespread throughout Australia, but cattle bred and raised in the Northern Territory were previously believed to be free of the disease. Between 2010 and 2016, 1061 cattle from the Northern Territory were slaughtered at a New South Wales abattoir and inspected for hydatid disease. The proportion of cattle reported infected with hydatid disease was 3.5%. Individual cattle identification numbers indicated that the cattle included in the study had most likely remained within the Northern Territory from birth until immediately prior to slaughter, so were assumed to have become infected within the region. We suspect that the sylvatic cycle of Echinococcus granulosus transmission could be responsible for infection of cattle in this region.     

Quantitative analysis of production traits in saltwater crocodiles (Crocodylus porosus): III. juvenile survival

Mortality records of 1302 juvenile crocodiles were available for analysis. Crocodiles that were slaughtered during this study were treated as censored (n = 2151). Additionally, records from animals that had neither died nor been slaughtered, i.e. were still alive in the production system (n = 1582), were censored at the last date of data collection. There were a total of 3733 censored records. The data were all full‐sib records from 29 parental pairs from Janamba Croc Farm (Northern Territory, Australia), collected over nine consecutive years. Data were analysed using an extension of Cox's proportional hazards model to include frailty (random) terms to account for genetic effects. Heritability of log survival time for juvenile crocodile survival was 0.15 (SE 0.04). The probability of a juvenile crocodile surviving to day 400 was estimated to be only 51%. These results are the first to quantify juvenile survival in a captive breeding situation. Also, this is the first heritability estimate of crocodile survival and is a fundamental element in the development of a genetic improvement programme.     

Prevalence and geographical distribution of Giardia spp. and Cryptosporidium spp. in dairy farms in Québec.

Giardiasis and cryptosporidiosis are parasitic infections of humans, domestic animals, and wildlife. In cattle, direct transmission through the contamination of barns and/or pasture appears to be the principal mode of infection. In Canada there is only one study reported in the literature on the prevalence of giardiasis and one study on the prevalence of cryptosporidiosis. These studies were done in Alberta and Manitoba, respectively. The purpose of this study was to determine the prevalence of Giardia spp. and Cryptosporidium spp. infections in dairy farms in Québec. Calves were sampled from 505 dairy farms. We are reporting that 45.7% of the farms were found to be positive for Giardia spp. and 88.7% were infected with Cryptosporidium spp.     

Prevalence and significance of gastrointestinal helminths and protozoa in South American Camelids in Switzerland

A cross sectional study was conducted to determine the prevalence and significance of endoparasitic infections in South American Camelids (SAC) in Switzerland. Qualitative and quantitative coproscopic examinations were performed in 38 farms during the grazing period. Management practices with possible interference with parasitic infections were analyzed. On the farm level prevalences of endoparasitic infections were: trichostrongyles 87%; Trichuris sp. 74%; Capillaria sp. 68%; Nematodirus battus 63%; Nematodirus sp. 53%; Dicrocoelium dendriticum 34%; Moniezia sp. 8%; Fasciola hepatica 5%; protostrongylids 5%; Eimeria macusaniensis 68%. The level of helminth egg excretion was generally low. The highest values were recorded for trichostrongyles with an average of all investigated farms of 53 eggs per gram of faeces. The mean trichostrongyle egg output was approximately three-fold in SAC on farms that also kept sheep and/or goats, although this difference was not significant (P = 0.11). Clinical trichostrongylidosis was not reported from any of the farms. The low infection level with gastrointestinal nematodes is attributed to the defaecation behaviour of the SAC depositing their faeces focally on small spots on pasture. As a consequence, pasture infectivity is largely restricted to the area adjacent to the dung piles. Dicrocoeliosis is regarded as the most relevant parasitic infection of llamas and alpacas in Switzerland causing severe clinical symptoms and death in untreated animals. Sixteen per cent of the owners regularily treated their herds against dicrocoeliosis using praziquantel at a dose of 50 mg/kg body weight orally.     

Parapoxvirus infections in New Zealand farmed red deer (Cervus elaphus)

Outbreaks of infection due to a parapoxvirus were reported on eight New Zealand deer farms. Scabby lesions were seen variably on the muzzle, lips, face, ears and neck of red deer (Cervus elaphus) with morbidity rates reaching 100%. On three farms multifocal lesions were also present on the velvet. Deaths were reported on two properties where the lesions were extensive and secondary bacterial infections had occurred. On one of these farms multifactorial disease was suspected. Poxvirus particles were seen by negative contrast electron microscopy in scab material from all eight properties. Morphologically the deer virus resembled a parapoxvirus, but restriction endonuclease analysis showed its DNA fragment patterns were distinct from those of orf (contagious ecthyma) virus.     

Survey for hydatidosis in cattle bred in the northern region of the Northern Territory of Australia

OBJECTIVE: To determine whether hydatidosis occurs in cattle bred in the northern region of the Northern Territory. DESIGN: A survey utilising two stage sampling was designed to provide 95% confidence of detecting hydatids in cattle with a herd prevalence of 10% and animal prevalence of 10%. PROCEDURE: For a 1 year abattoir killing season, lesions from the liver and/or lung were collected from 4348 cattle being slaughtered at a Northern Territory abattoir and examined for hydatid cysts. The origin of cattle was established through identification of the brand. RESULTS: Sample sizes of 41 or more Northern Territory bred cattle were achieved for each of 29 properties. No hydatid cysts were found in cattle bred in the northern region of the Northern Territory. CONCLUSION: This study provides evidence that a cycle of hydatid transmission does not occur in the northern region of the Northern Territory.     

Parasitic infections in dairy cattle around Hanoi, northern Vietnam

In northern Vietnam, dairy cattle are mainly managed in small-scale farms, where animals are kept confined and feeding occurs by cut and carry methods. In the present study the occurrence of parasitic infections was examined in five provinces around Hanoi. A total of 201 farms were visited, and 334 stool and 239 blood samples were collected from calves younger than 3 months, animals between 3 and 24 months and adult cows. Furthermore, 254 milk samples were collected from lactating animals. Coproscopical examination indicated a high prevalence of nematode eggs (Cooperia spp., Haemonchus and Oesophagostomum spp.) in animals (n=176) between 3 and 24 months (66%) and in adult cows (n=90; 54%). In these age groups the prevalence of Fasciola was 28% and 39%, respectively, and for Paramphistomum the prevalence was 78% and 82%, respectively. Fifty percent of the calves younger than 3 months (n=68) were positive for Giardia, and none for Cryptosporidium. Most Giardia isolates were identified as the non-zoonotic G. duodenalis assemblage E on the beta-giardin gene. The blood samples were examined with commercially available Svanovir((R))Elisa's for the presence of Anaplasma marginale and Babesia bigemina specific antibodies, and a prevalence of 28% and 54% was found, respectively. In the milk samples Neospora caninum specific antibodies (Svanovir((R))Elisa) were detected in 30% of the lactating animals. The present study demonstrates that parasitic infections occur frequently in dairy cattle around Hanoi although animals are mainly kept confined, and indicates that further research on the economic impact of these infections is needed.     

Enteric parasitosis in northern Thailand dairy heifers and heifer calves

A cross-sectional study was designed to: (1) determine the prevalences of enteric parasitic infections in dairy heifers and heifer calves (Bos taurus) in northern Thailand, and (2) determine the risk factors associated with the observed prevalences of infection. A stratified random sample of 87 farms was selected for study, and fecal and blood samples were collected from 439 out of 450 heifers and heifer calves from these farms. Fecal samples were processed by floatation and modified Benedek sedimentation methods, and then examined microscopically for the presence of enteric parasitic ova. Complete blood counts typically were within the reference range (done using standard methods). The overall prevalence for enteric parasites in heifers and heifer calves was 54%; most were of trematodes (41%) and nematodes (26%). Risk-factors analysis at the farm level yielded no significant results. Increased age significantly increased the odds of enteric parasite infection (OR=1.02, 95% CI 1.01-1.04).     

Seroprevalence of antibodies to Encephalitozoon cuniculi and Toxoplasma gondii in farmed domestic rabbits in Egypt

Rabbit sera from ten commercial farms representing three provinces in Northern Egypt (Behera, Alexandria and Khafr El-Sheikh) were submitted to serological screening for Encephalitozoon cuniculi using an enzyme-linked immunosorbent assay and for Toxoplasma gondii using an indirect hemagglutination test. Antibodies against E. cuniculi were detected in 36/240 (15%) sera examined while antibodies against T. gondii showed a seroprevalence of 22/194 (11.34%). Both infections were detected in all of the examined farms. These results are of epidemiological relevance and public health importance because of the recognized susceptibility of humans to E. cuniculi and T. gondii infections; therefore, routine screening examinations of farm rabbits are advised considering the zoonotic potential of these parasites.     

Diseases of young captive crocodiles in Papua New Guinea

To identify causes of mortality in young captive crocodiles, detailed necropsy and laboratory examination was done on 54 (30 Crocodylus porosus, 22 C. novaeguineae, 2 of unrecorded species). Although multiple infections often confounded interpretation it was concluded that the major infectious diseases, of approximately equal importance, were coccidiosis, bacterial septicaemia with Gram-negative organisms, and metazoan parasitism including ascariasis and pentastomiasis. A range of other lesions and agents was recognised, including keratitis, enteritis of unknown aetiology, non-suppurative encephalitis, traumatic peritonitis and trematodes located in renal tubules, gut and blood vessels. Some crocodiles in poor condition had only mild lesions associated with metazoan parasites and the cause of death or illness could not be clearly determined, although it was considered likely that adaptation failure was a contributing factor.     

Occurrence of concurrent infectious diseases in broiler chickens is a threat to commercial poultry farms in Central Ethiopia

Commercial poultry production is one of the flourishing ventures of animal production in Ethiopia. It has been providing to the demands of proteins at least to the urban population, though concurrent health constraints are hampering its intended potential. This study reports the influence of infectious diseases in commercial broiler farms in central Ethiopia. In this study, clinical signs, gross lesions, laboratory tests (serology, bacterial culture, histopathology and parasitology) and farm management data were used to identify major causes of outbreaks in an age specific manner in broiler chickens in three poultry farms in Debre Zeit, Central Ethiopia. The outbreaks detected in the farms were due to mycoplasmosis, salmonellosis, colibacillosis, coccidiosis and infectious bursal disease. It is observed that the occurrence of concurrent diseases in the farms significantly affects the productivity and health status of broilers. The risk factors that predispose birds to the various infections in the different farms studied were also recorded. In addition, recommendations were also provided.     

Skin disorders of the rabbit.

The integument is a common site of disease in the rabbit. Parasites, bacterial infections, and viral infections predominate; however, trauma, behavioral, and neoplastic diseases are common as well. Wild rabbits act as the reservoir of many parasitic and viral diseases of domestic rabbits.     

New patterns of Trichinella infection

Human and animal trichinellosis should be considered as both an emerging and reemerging disease. The reemergence of the domestic cycle has been due to an increased prevalence of Trichinella spiralis, which has been primarily related to a breakdown of government veterinary services and state farms (e.g., in countries of the former USSR, Bulgaria, Romania), economic problems and war (e.g., in countries of the former Yugoslavia), resulting in a sharp increase in the occurrence of this infection in swine herds in the 1990s, with a prevalence of up to 50% in villages in Byelorussia, Croatia, Latvia, Lithuania, Romania, Russia, Serbia, and the Ukraine, among other countries. The prevalence has also increased following an increase in the number of small farms (Argentina, China, Mexico, etc.) and due to the general belief that trichinellosis was a problem only until the 1960s. The sylvatic cycle has been studied in depth at both the epidemiological and biological level, showing the existence of different etiological agents (Trichinella nativa, Trichinella britovi, Trichinella murrelli, Trichinella nelsoni) in different regions and the existence of "new" transmission patterns. Furthermore, the role of game animals as a source of infection for humans has greatly increased both in developed and developing countries (Bulgaria, Canada, Lithuania, some EU countries, Russia, USA, etc.). The new emerging patterns are related to non-encapsulated species of Trichinella (Trichinella pseudospiralis, Trichinella papuae, Trichinella sp.), infecting a wide spectrum of hosts (humans, mammals including marsupials, birds and crocodiles) and to encapsulated species (T. spiralis, T. britovi, and T. murrelli) infecting herbivores (mainly horses). The existence of non-encapsulated species infecting mammals, birds and crocodiles had probably remained unknown because of the difficulties in detecting larvae in muscle tissues and for the lack of knowledge on the role of birds and crocodiles as a reservoir of Trichinella. On the other hand, it is not known whether horse and crocodile infections existed in the past, and their occurrence has been related to improper human behavior in breeding. The problem of horse-meat trichinellosis is restricted to France and Italy, the only two countries where horse-meat is eaten raw, whereas mutton and beef have been found to be infected with Trichinella sp. only in China.     

贵阳市养兔场主要疾病调查分析

为了解贵阳市养兔场疾病发生流行情况,采用文献检索、资料查阅和现场调查等方法对近10年来贵阳市养兔场疾病发生情况进行了统计分析。结果表明:在幼兔阶段主要发生更换饲料应激性腹泻和细菌性疾病,青年兔和成年兔主要发生大肠杆菌病、兔病毒性出血症和兔球虫病。调查结果为贵阳市养兔场疾病的预防与控制提供了参考依据。