Studies on Pathology of Hoof Affections in Equines

Abstract

The present work was designed to carry out research on Prevalence, Isolation and Identification of pathogen, Antibiotic Sensitivity to various pathogen, Gross and histoipathological study of hoof affections in equine species which include Horses, Mules and Donkey. Clinical examination of 87 equines was conducted, out of which 32 were found positive for different hoof affections. Samples (aseptic swabs, serum and tissues) were collected and processed in the laboratory. Out of 87 samples collected from 34 horses, 42 mules and 11 donkey, 11 horses, 17 mules and 4 donkeys were found positive for different hoof affections. The overall prevalence of hoof affections was highest in mules (40.47%) followed by donkey (36.36%) and then horses (32.35%).The prevalence recorded in different seasons was highest in summer (50%) then in winter (34.78%) and least in the monsoon (16.67%). The study was also carried out on the basis of age of affected animals and the data revealed that 30.76% cases observed in below 4 years age group, 44.23% in between 4-11 years age. Thereby highest level of prevalence of hoof affection was found in young animals as compared to adults. Male animals were found more susceptible (42.10%) than females (32.65%).Breed wise prevalence data in horses revealed that non-descript/local breeds were more largely affected (35% )than Marwari breed. In donkeys also, hoof affections were higher in non-descript animals (42.85%) than in Poitou breed (25%).The type of work taken from animals also affect prevalence of hoof affections.The data revealed that it was highest in riding horses (50%),followed by equines used for breeding purpose (43.75%), brickling by cart (41.17 %), brickling by pack (35.48%) and lowest in transportation of goods and carts (26.31%).Serum biochemical analysis of the animals showing various hoof affections was also carried out. The BUN, serum creatinine, serum bilirubin, total protein, serum albumin, serum globulin levels and A:G ratio were found lower than the apparently healthy animal. A total of 45 microbial isolates were collected for isolation and identification of pathogen which include 34.76% gram negative bacteria and 24% gram positive bacteria (71% were aerobic and 29 % anaerobic) in the samples collected from various hoof affections.While in antibiotic susceptibility test, the bacterial isolates from hoof affections of equines were highly sensitive to Gentamicin (94%) followed by Ampicillin/Sulbactum (87%), Amikacin (78%), Enrofloxacin (72%), Doxycycline (59%), Amoxycillin/ (56%) and Ceftiaxone (50%) while bacterial isolates exhibited complete resistant to metronidazole (100%), followed by Cotrimoxazole (91%), Streptomycin (87%), Penicillin G (84%), Oxytetracycline (69%), Ceftriaxone (50%) Gross and histopathology of the affected hooves were conducted by standard procedures. In present study, lesion of thrush, canker, maggoted wound, lacerated wound , foot abscesses and excessive growth were observed. Histopathological study of the affected tissues revalded keratinization and vacuolation of all the strata of the epidermis in the tissues affected with canker.The keratinocytes showed vacuoles surrounding its nucleus, the latter showed pyknotic and karryorhectic appearance with little marginalized and eosinophillic cytoplasm formation of large epidermal lacunae filled with eosinophilic fluid in the keratinocytes with pyknotic nuclei and perinuclear vacuoles indicated the ballooning degeneration of keratinocytes. Special staining with PAS, Mallory triple stain and massion trichome stain were carried out. In the cases, the infected hoof lesions, PAS positive reaction showed degenerative cells and fungal hyphae. Staining with Mallory triple stain revealed moderate increase in collegan fibres in dermis with more number of congested blood vessels. Staining with massion trichome stain also revealed thickened collagen fibers with infilteration inflammatory of cells in the corium of the affected hoove