Pathogenesis of helminths in equines

This review summarizes information on the clinical signs, gross and microscopic lesions associated with nematode and cestode infections and discusses the development of these conditions in the equine host.     

Use of ear tags and injectable transponders for the identification and traceability of pigs from birth to the end of the slaughter line

A total of 557 newborn piglets were used to compare eight identification devices, including one plastic ear tag as a control (C, n = 348) and two types of electronic ear tags (E1, n = 106; and E2, n = 103), and five types of injectable transponders (n = 557): small 12-mm (D12, n = 116; and S12, n = 110), medium 23-mm (T23, n = 108), and large (32-mm, T32, n = 115; and 34-mm, S34, n = 108). Injections were made s.c. in the auricle base (n = 248) and intraperitoneally (n = 309) using a new technique. All piglets were identified with two devices, but using electronic ear tags in conjunction with injection in the auricle was avoided on the same pig. Readability of devices was checked during fattening (until 110 kg BW) and slaughtering. On-farm losses were lower for control than for electronic ear tags (C = 1.1%; E1 = 8.8%; and E2 = 44.9%; P < 0.01); the latter also suffered electronic failures (E1 = 5.5%; and E2 = 55.1%; P < 0.001). On-farm losses of transponders injected in the auricle base were greater in large (S34 = 72.5%; and T32 = 46.3%; P < 0.05) than in small transponders (S12 = 19.4%; and D12 = 17.1%), but T23 (29.8%) only differed from S34. Transponder size did not affect on-farm losses for intraperitoneal injections in which only one loss was recorded (0.4%). All ear tags had similar losses during transportation to the slaughterhouse (1.2%), but no losses were observed in injectables. Slaughtering losses did not differ between ear tags (C = 11.2%; and E1 = 6.4%), but apart from losses, 12.8% of E1 failed electronically. Injection site affected losses and breakages during slaughtering (auricle base = 6.4%; and intraperitoneal = 0%), but recovery time did not significantly differ (auricle base = 28.6 s; and intraperitoneal = 18.9 s). Transponders in the auricle base were recovered by sight (30.2%), palpation (27.4%), or by cutting (42.5%). Intraperitoneal transponders were mainly recovered loose in the abdominal cavity (81.4%), whereas 18.6% fell on the floor. As a result, traceability varied significantly (P < 0.05) between control (86.7%) and electronic ear tags (0 to 68.1%) and injectable transponders, with the auricle base (17.8 to 75.0%) having lower values than intraperitoneal (98 to 100%). Intraperitoneal injection was a very effective tool for piglet identification and traceability, ensuring the transfer of information from farm to slaughterhouse. To warrant the use of this technique in practice, transponder recovery requires further investigation.     

Prevalence of piroplasmosis in equines in the Colombian Province of Cordoba

Summary Eighty-two equine sera from 13 farms in northern Colombia were examined for antibodies toBabesia caballi andB. equi using the complement fixation (CF) and the indirect fluorescent antibody (IFA) test. Seroreactors to both piroplasms were present on all farms. The IFA test indicated a prevalence of 90% forB. caballi and 94% forB. equi. The CF test detected antibodies toB. caballi in 41% and toB. equi in 65% of the animals. The prevalence of seroreactors in different age groups revealed a significant decline in CF antibodies toB. caballi in animals older than three years. IFA titres for bothBabesia spp. gradually declined with increasing age of the animals but were still present in most animals of the oldest age group (over nine years old).Anocentor nitens was found on all farms whereasAmblyomma cajennense was found only on two farms located on the coast.

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Prevalencia De Piroplasmosis En Equinos En La Provincia Colombiana De Cordoba

Resumen Se examinaron 82 sueros equinos provenientes de 13 fincas en el norte de Colombia, por la presencia de anticuerpos deBabesia caballi yB. equi, mediante la fijación del complemento y la prueba indirecta de anticuerpos fluorescentes. Se encontraron seroreactores a ambos piroplasmas en todas las fincas. La prueba de anticuerpos fluorescentes reveló una prevalencia de 90% paraB. caballi y 94% paraB. equi. La prueba de fijación del complemento detectó anticuerpos deB. caballi en 41% de animales y deB. equi en 65%. La prevalencia de seroreactores en grupos de diferentes edades reveló un descenso significativo en anticuerpos fijadores del complemento deB. caballi en animales mayores de tres años. Los títulos de anticuerpos fluorescentes para ambos piroplasmas declinaron con la edad, pero siempre estuvieron presentes inclusive en animales de nueve años de edad y más. La garrapataAnocentor nitens se encontró en todas las fincas, y elAmblyomma cajennense se encontró únicamente en dos de las fincas estudiadas.

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Prevalence De La Piroplasmose Equine Dans La Province De Cordoba, Colombie

Résumé On a recherché sur 82 sérums de chevaux de 13 fermes de Colombie du nord les anticorps anti-Babesia caballi etB. equi par les tests de fixation du complément (FC) et d'immunofluorescence indirecte (IFA). On a trouvé des sérums positifs dans toutes les fermes. Le test IFA donne une prévalence de 90% pourB. caballi et 94% pourB. equi. Le test FC détecte des anticorps anti-B. caballi chez 41% et anti-B. equi chez 65% des animaux. La prévalence des réagissants dans les groupes d'âge montre un déclin significatif des anticorps fixant le complément pourB. caballi chez les animaux de plus de 3 ans. Les titres IFA pour les deuxBabesia spp. déclinent graduellement avec l'âge mais sont toujours présents chez la plupart des animaux du groupe le plus âgé (plus de 9 ans). On a trouvéAnocentor nitens dans toutes les fermes, maisAmblyomna cajennense dans uniquement deux fermes de la région côtière.

     

Anti-insect defensive behaviors in equines post-West Nile virus infection

West Nile virus (WNV), a zoonotic mosquito transmitted Flavivirus, has had significant health effects on horses in the United States, with over 23,000 United States equine cases since the disease was first recognized in 1999. Previous research has focused on how this disease progresses and affects equids days to weeks post infection. The purpose of this study was to evaluate if permanent equine behavioral changes had occurred in horses that had recovered from acute West Nile fever or encephalitis. Specifically, we examined if surviving this disease caused changes in the defensive behaviors of the animal against biting and stinging insects, presumably because of neurological sequelae that can result from the infection. Results from behavioral observations and neurologic reflex testing suggest that long-term survivors of WNV do not show a change in the frequency or types of behaviors used compared to uninfected horses, supporting the concept that lasting deficits from WNV usually resolve within the following 1–3 years post-infection. However, microhabitat and grouping behavior did have a significant impact on the frequency of defensive behaviors, with indoor locales and larger groups of horses showing less insect avoidance behaviors. These principles may play a more pivotal role in protecting equines from biting insects and disease than thought previously.     

Serosurveillance for Japanese encephalitis virus infection among equines in India

The seroprevalence of Japanese encephalitis virus (JEV) among equines was evaluated from January 2006 to December 2009 in 13 different states of India by hemagglutination inhibition (HI) test and virus neutralization test (VNT). Antibodies against JEV were detected in 327 out of 3,286 (10%) equines with a maximum prevalence reported in the state of Manipur (91.7%) followed by Gujarat (18.5%), Madhya Pradesh (14.4%), and Uttar Pradesh (11.6%). Evidence of JEV infection was observed in equines in Indore (Madhya Pradesh) where a 4-fold or higher rise in antibody titer was observed in 21 out of 34 horses in November 2007 to October 2006. In March 2008, seven of these horses had a subsequent 4-fold rise in JEV antibody titers while this titer decreased in nine animals. JEV-positive horse sera had a JEV/WNV (West Nile virus) ratio over 2.0 according to the HI and/or VNT. These results indicated that JEV is endemic among equines in India.