Straight Egyptian Arabian skull morphology presents unique surgical challenges compared to the Thoroughbred: a computed tomography morphometric anatomical study.

OBJECTIVE: The objective of this study was to compare the skull morphology of the Straight Egyptian Arabian (SEAR) to the Thoroughbred (TB), using computed tomography (CT) in the context of surgical procedures commonly performed on the equine head. ANIMALS: Measurements relating to surgical considerations of the equine head were taken from 29 clinically normal adult horses (15 SEAR, 14 TB). PROCEDURES: A clinical prospective study. Standing skull CTs were performed. Fourteen gross and 10 CT measurements were taken. RESULTS: Several variables showed a significant difference between groups, in all cases greater in TB. Head length (P < .001) and facial crest length (P < .001) were significantly shorter in SEAR than TB. The head length was shorter relative to body height in SEAR (P < .001). The lateral length of a virtual maxillary bone flap was shorter in SEAR (P < .001). SEAR had smaller craniofacial angles than TB (P = .018). CLINICAL RELEVANCE: SEAR skull morphology differs significantly from TB, making surgical approaches potentially more challenging. Compared with TB, the shorter facial crest in the SEAR group could contribute to poor surgical access to the maxillary sinus in SEAR due to shorter maxillary flap lengths. Significant differences in the craniofacial angles between SEAR and TB suggest similarities between SEAR and brachycephalic dog breeds, warranting further investigation.

Ultrasound-guided injection technique of the equine cervical nerve roots.

Radiculopathy in horses is often a diagnosis of exclusion because of the non-specific clinical signs related to neck pain and possible forelimb lameness. There are no reported treatment options in the equine veterinary literature. The purpose of the study was to describe an ultrasound-guided injection of the cervical nerve root C3 to C8, to evaluate accuracy, time and safety and to anticipate possible complications on clinical cases. Under general anesthesia and with ultrasound guidance, five horses were injected from C3 to C8 with 1.5mL mix of contrast and latex. Immediately after euthanasia, the necks were taken for CT examination and then dissection was performed 3 days later. Data regarding the accuracy of injection, the presence of injectate in the nerve root, vertebral vessel or vertebral canal were recorded from both CT and dissection. The time of injection and ability to visualize the nerve root prior to injection were also recorded. Out of 60 intended injections, 55 (CT images) and 57 (dissection) led to injectate deposited within the target zone with direct contact between contrast/latex and cervical nerve roots noted in 76.4% and 73.7%, respectively. Presence of contrast/latex injectate within nerves (≤11%), vertebral vessels (<4%) and canal (<4%) were rarely encountered. No variation on success rate or safety noted based on the site of injection. The technique described has excellent accuracy, with injectate deposition in direct contact (≈75%) or close vicinity (≈25%) of C3-C8 cervical nerve roots. Injectate diffusion is likely to further improve success rate. Rare presence of injectate within nerve/sheath, vertebral vessels/canal along with diffusion warrants caution when performing this procedure in clinical cases.

Serological status of mares in parturition and the levels of antibodies (IgG) against protozoan family Sarcocystidae from their pre colostral foals.

Protozoa from the family Sarcocystidae are agents of reproductive and neurological disorders in horses. The transmission of these protozoa may occur via horizontal or vertical means, and the frequency and potential of the later is not fully elucidated in horses. Thus, the aim of study was to correlation levels of antibodies in mares with pre colostral foals seropositive and assess the level and distribution of antibodies against Neospora spp., Sarcocystis neurona and Toxoplasma gondii, in mares and pre colostral foals at the parturition. The blood samples were collected from mares immediately after parturition and from newborns before the ingestion of colostrum, and sera were analyzed for the presence of IgG by ELISA. It was found that 21.5%, 33.7% and 27.6% of mares were seropositive for Neospora spp., S. neurona and T. gondii, respectively; foals had antibodies at a rate of 8.3%, 6.6% and 6.6% for Neospora spp., S. neurona and T. gondii, respectively. Additionally, paired samples from mares and pre-colostral foals revealed an overall negative correlation between the serum reactivity against these three parasites and suggested that seronegative mares, or those with low to intermediate antibody levels, have a higher risk of giving birth to seropositive foals.

The importance of vertical transmission of Neospora sp. in naturally infected horses.

Neospora spp. is a intracellular protozoan phylogenetically closely related to Toxoplasma gondii and Sarcocystis neurona, and it can infect horses leading to the development of reproductive or neurological diseases. We determined the presence of antibodies to Neospora sp. in mares at their parturition time and determine the frequency of vertical transmission in healthy foals to verify the importance of transplacental transmission. The samples were analyzed by indirect immunofluorescence antibody test, showing that seroprevalence in mares is higher than in foals and seropositive mares are likely to transmit the neosporosis to their offspring. This shows that endogenous challenge occurs in horses, and it suggests that this protozoan can be disseminated by means of transplacental transmission in horse species.

Claudicação em cavalos Crioulos atletas / Lameness in athletic Criollo horses

O objetivo deste trabalho foi identificar as principais causas de claudicação em cavalos Crioulos em treinamento para a prova do Freio de Ouro e competições de rédeas. Foram avaliados os registros clínicos de 201 cavalos Crioulos, 5,6 2,1 anos de idade, submetidos a exame físico devido à presença de claudicação ou histórico de baixo rendimento atlético entre os anos de 2002 a 2009. A claudicação foi localizada nos membros torácicos e pélvicos em 47,1 por cento (n=105) e 52,9 por cento (n=118), respectivamente. Nos machos, houve uma predominância de claudicação nos membros pélvicos (60,0 por cento) e nas fêmeas nos membros torácicos (57,1 por cento). Nos membros torácicos, 17,1 por cento (18/105) das alterações foram diagnosticadas proximais à articulação metacarpofalangeana, 14,3 por cento (15/105) na articulação metacarpofalangeana e 68,6 por cento (72/105) estavam localizadas distais à articulação metacarpofalangeana. Nos membros pélvicos, 78,8 por cento (93/118) apresentaram a origem da dor na região do tarso, 17,8 por cento (21/118) proximal ao tarso e 3,4 por cento (4/118) distal ao tarso. As articulações interfalangeanas distais e intertarsiana distal/tarsometatarsiana são importantes fontes de dor e inflamação e estiveram mais frequentemente envolvidas em claudicações de membro torácico e pélvico, respectivamente. Os cavalos Crioulos apresentam problemas de claudicação semelhantes aos descritos em outras raças que participam de provas de rodeio.

This study aimed to identify the source of lameness in Criollo horses that are competing in the most important discipline for this breed in Southern Brazil and also in reining competitions. Clinical records of adult Criollo horses (n=201), 5.6 2.1 years of age, that underwent lameness examination due to history of poor performance or lameness between 2002/2009 were analyzed. Lameness was diagnosed in the front limbs in 47.1 percent (n=105) and in the hind limbs 52.9 percent of the cases (n=118). In males 60.0 percent of the lameness cases were located in the hind limbs. In females 57.1 percent of the lameness cases were located in the front limbs. In the front limbs (47.1 percent, n=105/201), problems proximal to the fetlock were diagnosed in 17.1 percent (18/105). Fetlock problems were diagnosed in 14.3 percent (15/105) and lesions located distal to the fetlock level were seen in 68.6 percent (72/105) of the lameness cases diagnosed in the front limbs. In the hind limbs, problems located proximal to the tarsus were seen in 17.8 percent (21/118), 78.8 percent (93/118) in the tarsus and 3.4 percent (4/118) of the cases were seen distal to the tarsus. The distal interfalangeal joint in the front limbs and the distal tarsal joints in the hind limbs were the two most important sources of lameness. Criollo horses presented similar lameness problems as described in other show horses (reining, cutting and roping). This is the first lameness study done in Criollo horses and it will help to better understand the musculoskeletal diseases affecting this breed.