Prevalence of subclinical infectious bursal disease and its significance in India

Summary From a total of 32 poultry flocks 1,176 serum samples were screened by the agar gel precipitation test and 314 (26·7%) were positive for antibodies to infectious bursal disease virus (IBDV). Prevalence of infection on the farms ranged from 8·88 to 53·84 per cent. The prevalence was highest (61·82%) in chickens between 7 and 11 weeks old and lowest (3·92%) in those above 22 weeks of age. In commercial broilers and layers 51·61 and 17·78% respectively were seropositive reactors. The high prevalence of subclinical IBD and its economic significance are discussed.

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Resumen Un mil ciento setenta y seis sueros (1.176), fueron procesados mediante la prueba de precipitación en agar gel y 314 (26·7%) fueron positivos a anticuerpos de bursitis infecciosa (BI). La prevalencia de la infección en granjas avícolas varió entre 8·88 y 53·84 por ciento. La prevalencia fue más alta en pollos entre siete y 11 semanas de edad, siendo baja (3·92%) en aquellos por encima de 22 semanas. En pollos de engorde y ponedoras, los reactores seropositivos fueron 51·61 y 17·78%, respectivamente. Se discute la alta prevalencia de la BI y su significado económico.

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Résumé Sur un total de 32 élevages de volailles, 1176 échantillons de sérums ont été examinés au moyen du test de précipitation en gélose; 314 (26,7 p. 100) étaient positifs vis-à-vis de la maladie de Gumboro (bursite infectieuse). La prévalence de cette infection en milieu fermier allait de 8,88 à 53,84 p. 100. Elle était plus élevée chez les poulets (61,82 p. 100) agés de 7 à 11 semaines et moins prononcée (3,29 p. 100) chez ceux agés de plus de 22 semaines. Dans les élevages commerciaux et chez les pondeuses 51,61 et 17,78 p. 100, respectivement, ont réagi positivement. Les auteurs discutent de l'importance de la bursite infectieuse subclinique et de sa répercussion économique.

     

Prevalence of selected infectious disease agents in cats from Arizona

The objective of this study was to use polymerase chain reaction (PCR) assays to determine the prevalence of Ehrlichia species, Anaplasma phagocytophilum, Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum' and Bartonella species from feral and relinquished cats in Phoenix and Nogales, Arizona. DNA from one or more of the organisms was amplified from 31 of 112 blood samples (27.7%). DNA consistent with Bartonella clarridgeiae 15 (13.4%), Bartonella henselae 14 (12.5%), 'Candidatus M haemominutum' 9 (8.0%), and M haemofelis 5 (4.5%) were detected. DNA of Ehrlichia species, Neorickettsia risticii, or A phagocytophilum was not amplified. Failure to amplify DNA of A phagocytophilum may relate to the absence of appropriate tick vectors. Failure to amplify Ehrlichia species DNA suggests that cats were not exposed, exposed but not infected, or infected but the DNA was not detected by the PCR assay used in this study. The Bartonella species and hemoplasma results suggest flea control should be maintained.     

Prevalence of subclinical coccidiosis in broiler farms in Turkey

The presence of Eimeria spp. oocysts in fecal samples collected from 1,108 broiler houses in six regions, representing about 12% of all broiler farms in Turkey, was studied using the modified McMaster method. The age of the chickens in the 1,108 pens varied from 1 to 50 days. Oocysts were found in 602 (54.3%) of these broiler houses, and the mean OPG (oocysts per gram of feces) in those samples was 36,498.7 (50–952,000). No indication of clinical coccidiosis or other clinically evident infection or wide mortality was encountered in any of the pens studied. Further study showed that the age of the chickens, the occurrence of diarrhea on the houses and the density of broiler breeding in the area correlated with subclinical coccidiosis prevalence.     

Newcastle disease in a vaccinated flock which had experienced subclinical infectious bursal disease

A flock of 4,500 Cobb broilers inoculated with Newcastle disease vaccine intra-ocular strain B1 type at 10 days of age developed clinical signs of the disease 19 days later; the mortality rate was 71%. Necropsy examinations showed characteristic lesions. Newcastle disease virus was isolated and identified in the allantoic fluid of embryonating chicken eggs by haemagglutination and haemagglutination-inhibition tests. Histopathological examination showed that follicles of the bursa were depleted of lymphocytes, had many large cavities and were being repopulated by newly formed healthy lymphocytes. Both the acute and convalescent serum samples were positive for infectious bursal disease antibodies in agar gel precipitation tests. Haemagglutination inhibition titres of the acute and convalescent sera were 20 to 80 and 80 to 640 respectively. The vaccine failure may be due to either the subclinical bursal disease or the highly pathogenic nature of the wild Newcastle disease virus.     

Effects of blood donation on arterial blood pressure in retired racing Greyhounds

The purpose of this study was to evaluate changes in systolic arterial blood pressure (SABP) immediately after collection of blood for transfusion in retired racing Greyhounds. We prospectively evaluated 19 blood donor Greyhounds before and after the collection of a unit (450 mL) of blood. The SABP was measured with Doppler in the right forearm after the dogs had been in the blood collection room for a few minutes (PRE-FLOOR) and again 5-10 minutes after the dogs were placed on the table where they would be bled (PRE-TABLE). A total of 3-5 minutes after completing the blood collection, the SABP was measured again while the dogs were still in lateral recumbency on the table (POST-TABLE) and once more 60-90 minutes later, when the dogs were on the floor after completing the donation (POST-FLOOR). All dogs were monitored for clinical signs of hypotension, including depression, weakness, collapse, and pallor, for a minimum of 2 hours after donation. There was a significant difference in SABP for the group between PRE-FLOOR and POST-TABLE (P = .02) and between PRE-TABLE and POST-TABLE determinations (P = .01). There were no significant differences for any of the other time points; there were no adverse events. Therefore, we conclude that the collection of 450 mL of blood from normal Greyhounds results in a short-lived yet significant decrease in SABP, but the likelihood of adverse events is negligible.     

Prevalence of proteinuria in a canine oncology population

Objective

To evaluate the point prevalence of proteinuria in dogs presenting to the University of Georgia Oncology Service for the first time.

Materials and Methods

In this prospective study, 60 client‐owned dogs with a confirmed cancer diagnosis were included but those with lower urinary tract neoplasia were excluded. Each dog's signalment, cancer diagnosis, previous cancer treatments, current medications and travel history were recorded. Renal values, electrolytes, packed cell volume, total solids, systolic blood pressure, urinalysis, urine protein:urine creatinine and retinal examinations were recorded. Non‐proteinuric, borderline proteinuria and overt proteinuria were defined as urine protein:urine creatinine <0·2, ≥0·2 but <0·5, and ≥0·5, respectively. Urine culture was performed in dogs with active urine sediments or overt proteinuria.

Results

Twenty‐nine dogs were non‐proteinuric (48·3%), 22 (36·7%) borderline proteinuric and nine (15%) overtly proteinuric. None were azotaemic. Hypertension (systolic blood pressure ≥160 mmHg) was detected in 18 (30%) dogs. Of these, six were non‐proteinuric, nine borderline proteinuric, and three overtly proteinuric. Proteinuria was detected in 51% of dogs presented to our oncology service, the majority of which were classified as borderline.

Clinical Significance

The high proportion of proteinuria in dogs in this study suggests that screening for proteinuria in dogs with cancer may be prudent. Larger studies are required to correlate specific cancer types and the impact of treatment with the development, magnitude and persistence of proteinuria.     

Cromoglycate induces a rebound effect on blood/milk permeability in subclinical mastitis

Chronic subclinical mastitis represents a vicious cycle of constant tissue irritation by bacteria and inflammatory response of the host. Antibiotics have proven relatively inefficient in eliminating chronic mastitic infections. The use of anti-inflammatory agents in mastitis is controversial. Theoretically, the inflammation should not be suppressed as this is a host defence mechanism of the body. However, because it is uncertain whether the infection or chronic inflammation causes more harm to the tissue, there have been efforts to use anti-inflammatory agents such as glucocorticoids and antipyretic analgetics. The problem is that there is insufficient evidence as to which inflammatory mediators (histamine, kinins, prostaglandins, leukotrienes, PAF, interleukin-1 etc.) alone or in combination are important in mastitis.     

Prevalence of feline infectious peritonitis in specific cat breeds

Although known that purebreed cats are more likely to develop feline infectious peritonitis (FIP), previous studies have not examined the prevalence of disease in individual breeds. All cats diagnosed with FIP at a veterinary teaching hospital over a 16-year period were identified. Breed, sex and reproductive status of affected cats were compared to the general cat population and to mixed breed cats evaluated during the same period. As with previous studies sexually intact cats and purebreed cats were significantly more likely to be diagnosed with FIP; males and young cats also had a higher prevalence of disease. Abyssinians, Bengals, Birmans, Himalayans, Ragdolls and Rexes had a significantly higher risk, whereas Burmese, Exotic Shorthairs, Manxes, Persians, Russian Blues and Siamese cats were not at increased risk for development of FIP. Although additional factors doubtlessly influence the relative prevalence of FIP, this study provides additional guidance when prioritizing differentials in ill purebreed cats.     

Prevalence, causes and laboratory diagnosis of subclinical mastitis in the goat

Five goat herds were examined to determine the prevalence and causes of subclinical mastitis and to assess the value of some laboratory tests currently used on milk samples as aids in the diagnosis of caprine mastitis. In the 170 samples taken from the pairs of mammary glands of 85 goats, the prevalence of infection in the different herds ranged from 15 per cent to 79 per cent of halves. Just over one-third (36 per cent) of all halves were infected, the organisms isolated being coagulase-negative staphylococci (80 per cent), coagulase-positive staphylococci (16 per cent), alpha-haemolytic streptococci (2 per cent) and Pasteurella haemolytica (2 per cent). Neither anaerobic organisms nor mycoplasmas were found. Tests confirmed that the coagulase-positive staphylococci were pathogens but that the coagulase-negative staphylococci rarely caused detectable disease in the caprine udder. The large between-herd variation in the geometric mean cell counts of uninfected milk samples means that somatic cell counts, the Whiteside test and the California mastitis test, are unreliable as aids in the diagnosis of caprine mastitis.     

Prevalence of gastrointestinal bacterial pathogens in a population of zoo animals

Faecal prevalence of gastrointestinal bacterial pathogens, including Campylobacter, Escherichia coli O157:H7, Salmonella, Shigella, Yersinia, as well as Arcobacter, were examined in 317 faecal specimens from 44 animal species in Belfast Zoological Gardens, during July-September 2006. Thermophilic campylobacters including Campylobacter jejuni, Campylobacter coli and Campylobacter lari, were the most frequently isolated pathogens, where members of this genus were isolated from 11 animal species (11 of 44; 25%). Yersinia spp. were isolated from seven animal species (seven of 44; 15.9%) and included, Yersinia enterocolitica (five of seven isolates; 71.4%) and one isolate each of Yersinia frederiksenii and Yersinia kristensenii. Only one isolate of Salmonella was obtained throughout the entire study, which was an isolate of Salmonella dublin (O 1,9,12: H g, p), originating from tiger faeces after enrichment. None of the animal species found in public contact areas of the zoo were positive for any gastrointestinal bacterial pathogens. Also, water from the lake in the centre of the grounds, was examined for the same bacterial pathogens and was found to contain C. jejuni. This study is the first report on the isolation of a number of important bacterial pathogens from a variety of novel host species, C. jejuni from the red kangaroo (Macropus rufus), C. lari from a maned wolf (Chrysocyon brachyurus), Y. kristensenii from a vicugna (Vicugna vicugna) and Y. enterocolitica from a maned wolf and red panda (Ailurus fulgens). In conclusion, this study demonstrated that the faeces of animals in public contact areas of the zoo were not positive for the bacterial gastrointestinal pathogens examined. This is reassuring for the public health of visitors, particularly children, who enjoy this educational and recreational resource.     

Prevalence of obese dogs in a population of dogs with cancer

OBJECTIVE: To determine the body condition score (BCS) distribution for dogs examined at a teaching hospital and examine whether the BCS distribution for dogs with cancer differed significantly from the distribution for dogs without cancer. SAMPLE POPULATION: 1,777 dogs with cancer and 12,893 dogs without cancer. PROCEDURES: A retrospective prevalence case-control study was conducted that used medical records from 1999 to 2004. Information was collected on BCS (9-point system), age, breed, sex, neuter status, diagnosis, and corticosteroid administration. Body condition score at the time of examination for cancer (dogs with cancer) or first chronologic visit (dogs without cancer) was recorded. Logistic regression was used to compare BCS prevalence distributions between groups. RESULTS: The overall prevalence of obese dogs (BCS >or= 7/9) was 14.8% (2,169/14,670), and the overall prevalence of overweight dogs (BCS >or= 6/9 to < 7/9) was 21.6% (3,174/14,670). There was a significant difference in the BCS distribution between dogs with and without cancer, with a slightly lower prevalence of being overweight and obese in dogs with cancer. The prevalence of obese and overweight dogs varied with specific cancer types when compared with the prevalence for dogs without cancer. CONCLUSIONS AND CLINICAL RELEVANCE: Differences in obesity prevalence among cancer types is suggestive of an incongruous effect of this variable on cancer expression or a differential effect of specific cancer types on weight status. Systematic use of BCSs will help elucidate the association between obesity and cancer development.     

Prevalence of infectious diseases in feral cats in Northern Florida

Objectives of this study were to determine prevalence of infection in feral cats in Northern Florida with a select group of infectious organisms and to determine risk factors for infection. Blood samples or sera from 553 cats were tested with a panel of antibody, antigen or PCR assays. Male cats were at higher risk for FIV, Mycoplasma haemofelis, and M. haemominutum. Infection with either FeLV or FIV was associated with increased risk for coinfection with the other retrovirus, M. haemofelis, or M. haemominutum. Bartonella henselae had the highest prevalence and was the only organism that did not have any associated risk for coinfection with other organisms. Feral cats in this study had similar or lower prevalence rates of infections than those published for pet cats in the United States. Thus, feral cats assessed in this study appear to be of no greater risk to human beings or other cats than pet cats.     

Prevalence of infectious diseases in ring-necked pheasant flocks in Poland

The health status of ring-necked pheasants in view of the prevalence of infectious diseases was estimated in Polish pheasantries in the years 1997-2000. Anatomicopathological, microbiological and serological examinations were carried out on birds derived from 26 pheasantries, including birds randomly selected from 18 flocks and sick or dead birds sent from 8 pheasantries. Antibodies specific to the following viruses were detected in serum blood samples: HE, AE, AP, REO, AI, Adeno group 1, MD, ND, as well as Mycoplasma gallisepticum specific antibodies. However, in none of the examined flocks was the presence of antibodies against reticuloendoteliosis virus found. Marble spleen disease and salmonellosis proved to be the most frequent cause of death during the growing period.