Dog foods are designed to give the proper nutrition and specific requirements of these pets. Recently, the importance of Docosahexaenoic acid (DHA) and fatty acids were highlighted by dog food makers. Fish oil, a rich source of fatty acids, was demonstrated in various uses such as improving dull coat of dogs, remedy for allergies, relieving inflammation, supporting brain and eye development.
While there are specific studies that scientifically explain the functions of individual fatty acids, effects of doses of fatty acids, specifically DHA, in dog foods are not clear. DHA was proven to have beneficial effects on the brain development of young dogs and on the retina of growing and ageing dogs. There are claims of such benefits with the use of some dog foods but the methodology and results were poorly documented.
This proposal aims to determine the effects, if there are any, and the extent of effects of DHA as a component of dog food on the health and intelligence of dogs. The objectives of this proposal includes 1) to determine the effects of different levels of DHA in commercial dog food (Hill's Science Plan) on learning and training ability of dogs, 2) to determine the effects of DHA in dog food through health indicators such as dog fur or coat and c) to determine the effects of DHA in dog food on eye functions of dogs.
Fatty acids are forms of polyunsaturated f...
Those that they cannot produce but are instead obtained through external sources such as food are called essential fatty acids (Ackerman 1148).
Omega-3 fatty acids include Alpha-linolenic acid (ALA) deficiency of which is related to skin disease development, Eicosapentaenoic acid (EPA) which is involved in vasoconstriction and related cardiac function and Docosahexaenoic acid (DHA) which is essential for brain and retinal functions. ALA is convertible into EPA and EPA is considered a major mover of the omega-3 fatty acids and is found in the cell membrane (Leaf 197-198, Kenny et.al. 660, Giron et.al.198).
Omega-6 fatty acids on the other hand include Linoleic acid (LA) which is found in the skin, Gamma linolenic acid (GLA) and Dihomo-gamma-linolenic acid (DGLA) which are forms of LA, and Arachidonic acid (AA) which is involved in prostaglandin synsthesis. LA can be transformed into GLA. DGLA can be converted from GLA in the skin. LA is vital for optimizing skin's water permeability. AA in large amounts is detrimental to other fatty acids (Pitas 470, Campbell & Roudebush 82).
Docosahexaenoic acid (DHA) is a major constituent of brain phospholipids and serves an important function in sustaining structural and functional properties of membranes. DHA is coupled in glycerophospholipids generally with palmitic acid and stearic acid and with an additional long-chain polyunsaturated fatty acid which builds up in phosphatidylethanolamines. Adequate supply of DHA has been postulated to promote maximum neurological growth, information processing, the capacity to conduct electrical stimuli of nerve cells, and cognitive ability. There is consensus among experts that mammalian brain produces its own DHA during particular stages of intrauterine and