An experimental study with 22 ponies was conducted to investigate the effects of feeding a diet high in nonstructural carbohydrates (starch) on the laminae of lean ponies compared with obese ponies. The ponies were sorted into lean (body condition ≤4) and obese (body condition ≥7) groups and half of each group was fed either a low starch hay diet or a high starch diet with added sweet feed and plant sugars. After 7 days, laminar tissue samples were collected and analyzed to measure the activity of naturally occurring substances that trigger inflammation (inflammatory mediators) and the expression of genes that control inflammation.

Some insulin resistance was noted in the obese animals; however, most of the inflammatory mediators measured were similar between the lean and obese animals in both the low and high starch groups. Only one enzyme related to the synthesis of prostaglandins (COX-2) was increased in the ponies fed the high starch diet. The inflammatory cells seen in the laminar tissues and the activity of those cells also were similar among the treatment groups.

This study suggests the laminar inflammation characteristic of laminitis caused by sepsis (endotoxemia, colic, retained placenta) is not the same in the development of pasture-associated laminitis.

— Burns TA et al. EVJ 2015;47:489-493

Bar Shoes Linked To Lung Bleeding

Researchers in Australia studied Thoroughbred horses with exercise induced pulmonary hemorrhage (EIPH) at the racetrack. Over a year, 583 horses at 48 race meets were examined using an endoscope to look inside the trachea for signs…