SCIENTIFIC AND CLINICAL: In this issue – September 2010

Agricultural shows and communicable disease transmission in poultry · Capsule endoscopy in horse small intestine · Acute lameness from a bone metastasis in a horse · Tidal breathing flow volume loop in dogs with tracheal masses · Intracranial meningioma and facial myokymia in a dog · Caudal epidural flank anaesthesia using multiport catheters in cattle · Needle-free vaccination in sheep · Smoking vets in Australia     

Age-related differences in collagen crimp patterns in the superficial digital flexor tendon core region of untrained horses

Objective To measure collagen fibril crimp angles and lengths as well as collagen fibril mass-average diameters in central and peripheral regions of the superficial digital flexor tendon of wild horses, to ascertain any age-related changes in either region in the absence of imposed galloping exercise.
Design Measurements from a random cull of wild horses.
Sample population Superficial digital flexor tendon samples were taken from 23 wild horses ranging in age from two to ten years.
Procedure Horses were divided into 'young' (< 5 years, n = 10), 'middle-aged' (5 to < 10 years, n = 9) and 'old' groups (10+ years, n = 4) and the mean crimp angle, mean crimp length and collagen fibril mass-average diameter calculated for the central region, and for the peripheral region of each group. Differences between groups and regions were analysed using two-tailed t tests.
Results The crimp angle for the central region was found to decrease with age, so that in old horses it was smaller than that for the tendon periphery (P < 0.05). The crimp angle for the latter region did not alter significantly with age. Crimp period lengths and collagen fibril mass-average diameters did not show significant changes with age in either region.
Conclusion Reduction of the crimp angle in the core of the superficial digital flexor tendon occurs normally with age, as tendons of older animals would have undergone a higher number of loading cycles. It is possible that athletic training increases the frequency and/or the magnitude of high loading cycles experienced by the tendon, and may accelerate and worsen the normal load-related ageing process in the superficial digital flexor tendons of young performance horses, particularly in the central regions where lesions usually occur.     

In this issue – December 2010

Aged horses in Queensland · Pressor therapy in neonatal foals · Fluoroscopic stents for feline urethral obstruction · Intradermal sodium lauryl sulfate as an alternative to mulesing in lambs · Monepantel faecal residues and dung fauna · Surgical spaying in yearling Brahman heifers · Anthelmintic resistance in cattle nematodes