caa a22 4500 388060824 CHVBK 20180307125120.0 cr unu---uuuuu 161130e199804 xx s 000 0 eng 10.1017/S1357729800009528 doi S1357729800009528 pii (NATIONALLICENCE)cambridge-10.1017/S1357729800009528 Comparative digestibility and digesta flow kinetics in two breeds of sheep [Elektronische Daten] A study was conducted to compare apparent digestibility and digesta flow kinetics in the whole digestive tract in two breeds of sheep (Churra and Merino) offered alfalfa hay at about maintenance. Ten mature sheep (five Churra and five Merino) each fitted with a rumen cannula were used in the study. Apparent digestibility was determined by total faecal collection. Liquid (Co-EDTA) and solid (Cr-mordanted fibre) markers were used to estimate rumen volumes and digesta flows. There were no significant differences between Churra and Merino sheep either in dry-matter or fibre apparent digestibility (P > 0·05). Liquid and solid passage rates did not differ between breeds and the estimated total mean retention times were similar for both genotypes. The volume of liquid in the rumen was proportionately 0·14 greater in Churra than in Merino sheep, although the difference was not significant. Estimated saliva secretion was greater in Churra (11·6 (s.e. 0·77) I/day) than in Merino sheep (10·5 (s.e. 0·72) I/day) but the difference did not reach statistical significance. Solid contents of the rumen did not differ between breeds. Rumen particle density was lowest at 2 h after feeding and remained stable at other sampling times, with no significant differences between breeds. There were no significant differences between breeds in the urinary excretion of total purine derivatives but urinary excretion of allantoin and microbial nitrogen supply tended to be higher in Merino than in Churra sheep (P < 0·20). This was attributed to the smaller rumen pool size of Merino (8·0 (s.e. 0·62) kg) compared with Churra sheep (9·2 (s.e. 0·63) kg). The study indicated that there were no apparent breed differences between Churra and Merino sheep in digestibility and digesta passage when they were given a good-quality forage at a low level of intake. Copyright © British Society of Animal Science 1998 digesta kinetics nationallicence digestibility nationallicence saliva nationallicence sheep nationallicence water balance nationallicence Ranilla M. J. Departamento de Producción Animal I, Universidad de León, 24071 León, Spain López S. Departamento de Producción Animal I, Universidad de León, 24071 León, Spain Giráldez F. J. Departamento de Producción Animal I, Universidad de León, 24071 León, Spain Valdés C. Departamento de Producción Animal I, Universidad de León, 24071 León, Spain Carro M. D. Departamento de Producción Animal I, Universidad de León, 24071 León, Spain Animal Science Cambridge University Press 66/2(1998-04), 389-396 1357-7298 66:2<389 1998 66 ASC https://doi.org/10.1017/S1357729800009528 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S1357729800009528 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ranilla M. J. Departamento de Producción Animal I, Universidad de León, 24071 León, Spain NATIONALLICENCE 700 1- López S. Departamento de Producción Animal I, Universidad de León, 24071 León, Spain NATIONALLICENCE 700 1- Giráldez F. J. Departamento de Producción Animal I, Universidad de León, 24071 León, Spain NATIONALLICENCE 700 1- Valdés C. Departamento de Producción Animal I, Universidad de León, 24071 León, Spain NATIONALLICENCE 700 1- Carro M. D. Departamento de Producción Animal I, Universidad de León, 24071 León, Spain NATIONALLICENCE 773 0- Animal Science Cambridge University Press 66/2(1998-04), 389-396 1357-7298 66:2<389 1998 66 ASC CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge