Research suggests that changes in the concentration of selenium in the blood may play a role in crib-biting behaviour.
Selenium (Se) is an essential trace element, which acts as an antioxidant in cellular interactions.
Research by Arash Omidi and colleagues at the School of Veterinary Medicine, Shiraz University, Shiraz, Iran found an association between low serum selenium and crib-biting behaviour.
The study set out to find differences in blood samples taken from crib-biting and non-crib-biting (control) horses. Researchers measured various parameters including mineral trace elements, electrolytes, and the activity of some enzymes and hormones.
Ten crib-biting horses were enrolled in the study. They were housed singly in individual box stables in different premises around Shiraz. Ten healthy sex- and age-matched horses with no history of crib-biting were used as controls and maintained under similar housing conditions.
The research team collected blood samples from the crib-biting horses during a crib-biting session (which lasted at least 15 minutes with no gap greater than 2 minutes), and when the horses had not been crib-biting for at least 30 minutes. These samples were compared with those taken from the control horses.
Researchers found that serum Se concentration was significantly lower in crib-biting horses than in controls. Lowest levels were seen during crib-biting behaviour, but levels remained low compared to controls even when the horses were not crib-biting. No other significant differences between crib-biting horses and controls were found. Zinc (Zn) levels tended to be lower than normal at rest in the crib-biters, but returned to normal during crib-biting behaviour.
The research is published in the Journal of Veterinary Behavior. The authors conclude that alterations in serum levels of the essential trace element selenium, may play a role in the pathophysiology of crib-biting behaviour in horses.
They suggest “Further research should now investigate the functional significance of these alterations, perhaps by studying the effects on crib-biting of dietary supplements of Se and Zn.”
For more details, see:
Journal of Veterinary Behavior (2018) 23, 10-14
Potential role for selenium in the pathophysiology of crib-biting behavior in horses
Arash Omidi, Reza Jafari, Saeed Nazifi, Matthew O.Parker