Juan A. Corbera

The prevalence of Dirofilaria immitis in Gran Canaria, Canary Islands, Spain (1994–1996)

Blood samples from 2034 dogs were tested to detect Dirofilaria immitis antigen during three consecutive years (from 1994 to 1996) in Gran Canaria Island, Canary Islands, Spain. The prevalence of heartworm infection was 67.02% in 1994, 58.92% in 1995 and 52.18% in 1996, with a mean prevalence of 58.89%. Heartworm infection was more common in males (56.19%) than in females (43.81 %), in dogs aged between 3 and 6 years old. The distribution of the disease in the different climatic zones was studied. Chronological changes in the dogs prevalence for heartworm infection in the three consecutive years and the role of the epidemiological factors in the changes of the positive rates were evaluated.

Camel trypanosomosis in the Canary Islands: assessment of seroprevalence and infection rates using the card agglutination test (CATT/T. evansi) and parasite detection tests.

Trypanosomosis due to Trypanosoma evansi (surra) is a major enzootic disease of the dromedary camel. Thus, the purpose of the present study was to assess seroprevalence and infection rates in the Canary Islands using antibody(-card agglutination test-CATT/T. evansi) and parasite detection tests (micro-Haematocrit Centrifugation technique, Giemsa stained blood smears, microscopic examination of lymph node aspirates and mouse inoculation). PCV was also determined. 745 dromedary camels (483 females and 262 males) were examined. Trypanosomes were detected in seven animals. 36 animals yielded CATT positive results while 709 animals were negative. All parasitologically positive animals were also CATT positive. Results showed a good correlation between CATT positive and low PCV and a higher seroprevalence in older animals. Trypanocidal drugs have not been registered in Spain and, consequently, if vigilance is not exercised the prevalence could be increased in the future.

Current prevalence of Dirofilaria immitis in dogs, cats and humans from the island of Gran Canaria, Spain.

The island of Gran Canaria is a hyperendemic area for canine dirofilariasis. The aim of the present study was to provide data on Dirofilaria immitis in dogs, cats, and humans on this island in 2010. The data confirms the prevalence in the overall canine population (19%), with a considerably higher prevalence (43%) in the autochthonous breed of Canarian Warren hound. The prevalence in the feline population (33%) is higher than that of the canine population, and the existence of specific D. immitis antibodies in the inhabitants of the island of Gran Canaria (12%) is confirmed. In both cats and humans, the prevalence, according to the different climate areas on the island, is related to the prevalence of D. immitis in dogs in the same area, which shows the key epidemiological role played by the canine host with regard to the transmission to other hosts of D. immitis.

Trypanosomosis in Goats

Abstract:  Trypanosomosis is a major constraint on ruminant livestock production in Africa, Asia, and South America. The principal host species affected varies geographically, but buffalo, cattle, camels, and horses are particularly sensitive. Natural infections with Trypanosoma congolense, T. vivax, T. brucei, and T. evansi have been described in goats. Trypanosomosis in goats produces acute, subacute, chronic, or subclinical forms, being T. vivax, T. congolense, and T. evansi, the most invasive trypanosomes for goats. However, the role of goats in the epidemiology of trypanosomosis is largely discussed and not well understood. Thus, it has commonly been assumed that trypanosomosis presents a subclinical course and that goats do not play an important role in the epidemiology of the disease. This can partially be due to parasitemia caused by trypanosomes which has been considered low in goats. However, this assumption is currently undergoing a critical reappraisal because of goats may also serve as a reservoir of trypanosome infection for other species, including the human beings in the case of T. brucei rhodesiense. The present article describes the current status of trypanosomosis in goats in Africa, Asia, and South America. Pathogenesis, clinical features, diagnosis, and treatment of the different trypanosomes are also described. The possible role in the epidemiology of the disease in the different areas is also discussed.

Dirofilaria immitis infection in dogs: Cardiopulmonary biomarker levels

Cardiopulmonary biomarkers are biological parameters that can be objectively measured and quantified as indicators of pathogenic processes (heartworm disease) or as indicators of response to therapeutic intervention. To determine levels of cardiopulmonary biomarkers in canine dirofilariasis, measurements of cardiac troponin T, cardiac troponin I, myoglobin, and D-dimer concentrations were performed for dogs with and without evidence of adult heartworm infection. The results showed that levels of cardiac troponin T were undetectable in all dogs studied while levels of cardiac troponin I were higher in dogs infected with Dirofilaria immitis. In healthy dogs, levels of myoglobin and D-dimer were below detection limits of the instrument and were significantly higher in heartworm-infected dogs, notably in microfilaremic dogs. The results suggest the possibility of using troponin I and myoglobin as markers for cardiac damage and the D-dimer as a supportive tool for a diagnosis of pulmonary thromboembolism in dogs with cardiopulmonary dirofilariasis.

Clinical, Hematological, and Biochemical Findings in an Outbreak of Abortion and Neonatal Mortality Associated with Trypanosoma evansi Infection in Dromedary Camels

Abstract:  This article presents the clinical and laboratorial findings in an outbreak of abortions and high neonatal mortality attributable to Trypanosoma evansi infection in camels. A total of 16 females were diagnosed, 2 of which showed moderate signs of chronic form, particularly hyporexia and intolerance to exercise. The main laboratorial findings were regenerative anemia (hemolytic anemia), lymphocytic and monocytic leukocytosis, hyperproteinemia, hyperglobulinemia, hypoglycemia, serum urea increased, and serum iron decreased. The most characteristic finding in the examined females would be the uremia, probably due to the higher protein metabolism.

Use of the Miniature Anion Exchange Centrifugation Technique to Isolate Trypanosoma evansi from Goats

Abstract: DEAE (anion exchanger diethylaminoethyl)‐cellulose and mini Anion Exchange Centrifugation Technique (mAECT) allow salivarian trypanosomes to be separated from the blood of affected animals. The purpose of this study was to assess the mAECT in goats infected with T. evansi. Five adult Canary goats were inoculated intravenously with at least 1 × 105T. evansi isolated from a dromedary camel in the Canary Islands. The goats were monitored for specific antibodies and parasite detection. The inoculated goats became infected and the parasitemia remained very low but was persistent. For mAECT columns, the DEAE gel was equilibrated with phosphate‐buffered saline glucose. T. evansi was detected by its mobility with a microscope at low magnification (10 × 10). The mAECT proved to be more sensitive than blood smear and buffy coat but less sensitive than mouse inoculation. We conclude that in cases of very low parasitemia in goats, mAECT can be used when other parasite‐detection tests have failed.

Performance of serological tests for Trypanosoma evansi in experimentally inoculated goats.

Abstract: Natural Trypanosoma evansi infection in the Canary Islands has only been diagnosed in the camel population, but dissemination of the disease in other hosts has not been excluded. The objective of this work was to assess the performance of serological antibody tests in experimentally inoculated goats. Five Canarian goats were inoculated intravenously with at least 1 × 105T. evansi. The animals were kept for 8 months and checked monthly for the presence of the parasite and specific antibodies. The serological tests investigated were the direct card agglutination test CATT/T. evansi and the indirect card agglutination test LATEX/T. evansi. All animals became positive in the CATT/T. evansi 1 month post‐infection and remained positive with a minimum end‐titer of 1/4. Similar results were obtained with the LATEX/T. evansi, although at lower end‐titers (1/2). We conclude that CATT/T. evansi is adequate for assessing infection of Canarian goats by T. evansi.

An Outbreak of Nutritional Muscular Dystrophy in Dromedary Camels

Abstract Corbera, J.A., Morales, M., Pulido, M., Montoya, J.A. and Gutierrez, C. 2002. An outbreak of nutritional muscular dystrophy in dromedary camels. J. Appl. Anim. Res., 23: 117–122. An outbreak of nutritional muscular dystrophy (NMD) due to vitamin E/selenium deficiency in an intensive dromedary camel herd causing a mortality of 25 animals (22 calves and 3 adults) is described. From a total of 120 adult animals (84 females) 47 calved. 22 calves (younger than 3 months of age) showed clinical signs as weakness, reluctancy to move, muscular rigidity, progressive opisthotonus, stiff gait, difficulty to suck and to stand, ataxia, recumbency position, respiratory distress and death. Enteritis, pneumonia and sudden death were also observed in these animals. In the peripartum period 15 dams showed uterine prolapse, placental retention or clinical mastitis, 3 of which died later. Clinical peculiarities observed in these animals were opisthotonus, tail elevation and uterine prolapse, never described in dromedaries associated with NMD. Therapeutical dosages used (sodium selenite: 0.06 mg per kg subcutaneously, vitamin E: 640 mg of d-β-tocopherol per animal intramuscularly) and preventive dosage of 40 mg/kg of sodium selenite by oral route (by mineral block) resulted adequate in this species.

Multiple abscesses caused by Salmonella enterica and Corynebacterium pseudotuberculosis in a dromedary camel

A rare case of arthritis, peri-arthiritis and pleurits associated with Salmonella enterica and Corynebacterium pseudotuberculosis infection in a dromedary camel is reported. Articular infections caused by Non-typhoidal Salmonella have been exceptionally described in human medicine. To our knowledge, this would be the first description of articular infections associated with Non-thyphoidal Salmonella in other mammals than humans. Possible pathogenesis of the infection is discussed.