A comparative study of nutrient digestibility, kinetics of digestion and passage and rumen fermentation pattern in goats and sheep offered medium quality forages at the maintenance level of feeding

Abstract

The in vivo digestibility and the rates of degradation and passage of alfalfa hay (AH) and vetch straw (VS) were compared in three Granadina goats and three Segureña wethers fed at approximately maintenance level, using a change over design. The nylon bag technique was used to estimate the fractional rate of degradation of the feeds in the rumen. The fractional outflow rate of hay and straw particles was determined with chromium as a marker. No significant differences in the digestibility coefficients of nutrients between animal species were found. Nitrogen retention expressed as coefficients of both nitrogen intake and digested nitrogen was lower (P < 0.01) in goats than in sheep when VS was offered. There was no significant difference between goats and sheep in the effective degradability (measured at outflow rates in the range of 0.027 to 0.032 h-1) of dry matter (DM) for either forage. However, the effective degradabilities of the neutral detergent fibre (NDF) and crude protein (CP) of VS were lower (P < 0.01 and P < 0.001, respectively), in goats than in sheep. The degradation rates of DM, NDF and CP were not significantly different (P > 0.05) between goats and sheep. Also, the fractional rate of passage of particles from the rumen was not different (P = 0.056) between species, although there was a tendency for an increased outflow rate in goats. In a second experiment the effects of animal species, type of diet and frequency of feeding on rumen fermentation pattern were studied following a factorial design. Four goats and four wethers were used. They were randomly allocated to three dietary treatments: AH, VS or a 50:50 mixture of AH and VS (AH/VS). Rations were offered in two or three meals daily and samples of rumen content were obtained at 09.00, 11.00, 13.00, 15.00, 17.00 and 19.00 h. No difference in rumen pH was found between goats and sheep. Total volatile fatty acids and ammonia concentrations were higher (P < 0.001) in sheep than in goats. The molar proportions of acetate and isovalerate were higher (P < 0.01 and P < 0.001, respectively) in goats than in sheep, whereas the opposite was true for the molar proportion of n-butyrate. Feeding frequency had a slight effect on the rumen parameters measured. It is concluded that only minor differences in the digestive capacity and rumen activity of sheep and goats can be expected when they are fed on medium quality forages.

Oral pharmacokinetics of the acidic drugs, diclofenac and sulfamonomethoxine in male Shiba goats

“…This result suggests that absorption of DF from the forestomach of male Shiba goats may have been markedly high. The pH value of the rumen juice in this study was 6.4, as has been reported previously [11]. Furthermore, the pKa of DF is 4 [20], suggesting that negligible DF molecules exist as an unionized form (0.1–1%) in the contents of the rumen.…”

“…Since the absorption of drugs from the small intestines is generally fast, gastric emptying is the determining factor for drug absorption after the oral administration of drugs [10, 21]. Markedly higher k a values were obtained for SMM in pigs and DF in rats after their intraduodenal administration than after their oral administration [11, 18]. This may also have been the case for the male Shiba goats used in the present study.…”

A comparative study of the effect of two-stage olive cake added to alfalfa on digestion and nitrogen losses in sheep and goats

“…Nú ñ ez-Herná ndez et al (1991) reported a higher N digestibility in goats than in lambs when fed mountain mahogany (Cercocarpus montanus) leaves treated or untreated with PEG. Several nutritional studies comparing sheep and goats reported no differences in nutrient digestibility when moderate-or good-quality forages were fed (Isac et al, 1994;Molina Alcaide et al, 2000) but fibre digestibility of low-quality forages was greater in goats than in sheep (Doyle et al, 1984). In our work only ADF digestibility of AHCO and AHCOP diets differed between goats and wethers, being higher for goats, while values for AH diet remained similar for both animal species.…”

In vitro–in vivo study on the effects of plant compounds on rumen fermentation, microbial abundances and methane emissions in goats

“…Neutral detergent fibre with heat-stable amylase and expressed inclusive of residual ash (NDF), acid detergent fibre expressed inclusive of residual ash (ADF) and ADL contents were analysed following the methodology described by Van Soest et al (1991), using an ANKOM Model 220 Fibre Analyser (Macedon, NY, USA). The individual VFA concentrations were analysed using the GC technique described by Isac et al (1994). The methane concentration was determined by GC using a HP Hewlett 5890, Packard Series II gas chromatograph (Waldbronn, Germany).…”