Reprod. Nutr. Dev. 42 (2002) 295-305
DOI: 10.1051/rnd:2002026

Influence of the load of nylon capsules on their passage through the digestive tract and specific gravity

Jirí Trináctý^a, Petr Homolka^b, Michal Richter^a, Martin Sustala^a and Ales Vymetal<sup>b

a</sup>  Research Institute of Animal Nutrition, Ltd., 691 23 Pohorlelice, Czech Republic
^b  Research Institute of Animal Production, Uhríneves, 104 00 Praha, Czech Republic

(Received 10 September 2001; accepted 28 May 2002)

Abstract
The passage and specific gravity of nylon capsules were evaluated in five trials. In individual trials, different lactating cows were fed the same diet consisting of maize silage, alfalfa hay and concentrate. In each trial the different feeds (or no feed) were used to fill the capsules. The capsules were made of nylon cloth (42 m pore size, 10 mm external diameter). The different weights of the load (L1-L5) were obtained using a combination of 2 and 3 mm stainless steel balls. The highest recovery of the capsules was obtained with the L3 and L4 loads (91.4 and 92.3%, resp.). After 14 hours of incubation in the rumen, the calculated values of functional specific gravity of the capsules ranged from 0.92 to 2.05 g cm ^-3. It was concluded that L3 (one 2 mm and one 3 mm ball) was the suitable weight of the load.

Key words: passage / nylon capsule / different weight / dairy cow

Correspondence and reprints: Jirí Trináctý
    e-mail: trinacty@vuvz.cz

© INRA, EDP Sciences 2002