Effect of the size of hay particles on digestion in the sheep

✍ Scribed by A. H. Alwash; P. C. Thomas

• Publisher: John Wiley and Sons
• Year: 1974
• Tongue: English
• Weight: 435 KB
• Volume: 25
• Category: Article
• ISSN: 0022-5142
• DOI: 10.1002/jsfa.2740250205

✦ Synopsis

Abstract

Four sheep fitted with permanent rumen cannulae were used to study the digestion of a hay diet prepared, by grinding, in four forms differing in particle size. Each form of the diet was given at two levels of feeding, 1.1 and 2.4 times the energy requirement for maintenance of bodyweight. At each level, the digestibility of organic matter and of other constituents in the diet and the mean retention time of food residues in the alimentary tract decreased from the coarsest to the most finely ground form of hay. The digestibility of organic matter (D) was related to the mean particle size (in nm) in the diet (p) such that D = 57.5 + 16.97 p^2^ (P < 0.001) at the low level of feeding and D = 51.5 + 23.75 p^2^ (P < 0.001) at the high level. There were corresponding relationships for the mean retention time of food residues (R) such that R = 69.1 + 64.0__p__^2^ (P < 0.01) and R = 49.6 + 50.2__p__^2^ (P < 0.01). There were no marked variations with the form of the hay in the rate of digestion of hay in nylon bags, or cotton threads, suspended in the rumen or in the pH or concentrations of ammonia or total or individual short‐chain fatty acids in the rumen fluid.

It is suggested that changes in digestion associated with the provisions of forages in ground forms can be related to the size of particles in the ground food and the level at which it is fed.