- L.M.F. Ferreira (1)
- V.J.T. Ginneken van (1)
- C.M. Guedes (1)
- E.A. Huisman (1)
- W. Martin-Rosset (2)
- R.O.A. Ozorio (1)
- M.A.M. Rodrigues (3)
- A.S. Santos (3)
- F. Silva (2)
- J.A.J. Verreth (1)
- M.W.A. Verstegen (1)
Effect of nitrogen sources on in vitro fermentation profiles and microbial yield using equine caecal contents
Santos, A.S. ; Ferreira, L.M.M. ; Martin-Rosset, W. ; Cone, J.W. ; Bessa, R.J.B. ; Rodrigues, M.A.M. - \ 2013
Animal Feed Science and Technology 182 (2013)1-4. - ISSN 0377-8401 - p. 93 - 99.
gas-production profiles - protein fermentation - streptococcus-bovis - rumen - growth - bacteria - acid - efficiency - kinetics - balance
The effect of different nitrogen and carbohydrate sources on in vitro fermentation profile and microbial yield of equine caecal contents was assessed. For this purpose, caecal contents were collected from 3 geldings, fed at maintenance level twice a day, and diluted with a buffer mineral solution (1:10, v/v). Caecal inoculum was then used in incubationsusing the gas production technique in one of the following treatments: mixture of rapidlyfermentable carbohydrates (glucose, xylose and starch); 25 mg of N in the form of casein; 25 mg of N in the form of urea; mixture of rapidly fermentable carbohydrates plus 25 mg of N in the form of casein; mixture of rapidly fermentable carbohydrates plus 25 mg of N in the form of urea; no substrate. Total volatile fatty acids (VFA), ammonia nitrogen and gas production were measured after a 24-h incubation. Microbial biomass was estimated using adenine and guanine bases as internal markers, and microbial growth efficiency (YATP) and gas efficiency (Egas) were estimated. Results showed a higher fermentative activity when nitrogen together with soluble carbohydrates was provided in contrast to treatments that were energy or nitrogen limited. When nitrogen and carbohydrates are provided, besides an efficient growth of the microbial population, there is a marked increase in total VFA and gas production. Although the caecal microbial population will respond to casein addition with an increase in VFA and gas production, microbial growth efficiency will be lower compared to the addition of urea as nitrogen source, indicating that the microbial population would mainly use non protein nitrogen for growth.
The influence of casein and urea as nitrogen sources on in vitro equine caecal fermentation
Santos, A.S. ; Ferreira, L.M.M. ; Martin-Rosset, W. ; Cotovio, M. ; Silva, F. ; Bennett, R.N. ; Cone, J.W. ; Bessa, R.J.B. ; Rodrigues, M.A.M. - \ 2012
Animal 6 (2012)7. - ISSN 1751-7311 - p. 1096 - 1102.
rumen microbial-growth - gas-production - amino-acids - protein - ponies - digestibility - metabolism - peptides - kinetics - invitro
To access the fermentative response of equine caecal microbial population to nitrogen availability, an in vitro study was conducted using caecal contents provided with adequate energy sources and nitrogen as limiting nutrient. Two nitrogen (N) sources were provided, protein (casein) and non-protein (urea). Caecal fluid, taken from three cannulated horses receiving a hay–concentrate diet, was mixed with a N-free buffer–mineral solution. The influence of four N levels (3.7, 6.3, 12.5 or 25 mg of N in casein or urea) was studied using the gas production technique. Total volatile fatty acids (VFA), NH3-N and gas production were measured after a 24-h incubation period. Microbial biomass was estimated using adenine and guanine bases as internal markers, and ATP production was estimated stoichiometrically. Microbial growth efficiency (YATP) and gas efficiency (Egas) were estimated. Fermentation with casein as the sole N source was generally characterized by lower total VFA, NH3-N, total gas production and higher acetate : propionate (A : P) ratio and YATP than with urea. Results herein presented indicate that, under these in vitro conditions, caecal microbial population does in fact use urea N, but less efficiently than casein in terms of microbial growth
|In vitro equine caecal fermentation of different casein levels
Santos, A.S. ; Ferreira, L.M.F. ; Cotovio, M. ; Silva, F. ; Guedes, C.M. ; Cone, J.W. ; Bessa, R.J.B. ; Rodrigues, M.A.M. - \ 2010
In: 5th European Workshop on Equine Nutrition : The impact of nutrition on the health and welfare of horses. - Wageningen : Wageningen Academic Publishers - ISBN 9789086861552 - p. 199 - 202.
Effects of exercise on l-carnitine and lipid metabolism in African catfish (Clarias gariepinus) fed different dietary l-carnitine and lipid levels
Ozorio, R.O.A. ; Ginneken, V.J.T. van; Bessa, R.J.B. ; Verstegen, M.W.A. ; Verreth, J.A.J. ; Huisman, E.A. - \ 2010
The British journal of nutrition 103 (2010)8. - ISSN 0007-1145 - p. 1139 - 1150.
trout oncorhynchus-mykiss - bream pagrus-major - high-fat diets - salmo-salar l - rainbow-trout - growth-performance - exhaustive exercise - nutritional supplements - intermediary metabolism - swimming performance
African catfish (Clarias gariepinus) were fed four isonitrogenous diets (34 % crude protein), each containing one of two lipid (100 or 180 g/kg) and two l-carnitine (15 or 1000 mg/kg) levels. After 81 d of feeding, thirty-two fish (body weight 32 g) from each dietary group were randomly selected, sixteen fish were induced to a 3-h swim (speed of 1.5 body length (BL)/s), while the other sixteen fish were kept under resting condition. Fish fed 1000 mg l-carnitine accumulated 3.5 and 5 times more l-carnitine in plasma and muscle, respectively, than fish fed the 15 mg l-carnitine. Muscle l-carnitine content was significantly lower in exercised fish than in rested fish. High dietary lipid level (fish oil) led to an increase in muscle n-3 PUFA content and a decrease in SFA and MUFA content. In liver, the increase in dietary lipid level resulted in an increased levels of both n-6 and n-3 PUFA. l-carnitine supplementation significantly decreased n-3 PUFA content. Exercise decreased n-3 PUFA in both muscle and liver. Plasma lactate and lactate dehydrogenase, normally associated with increased glycolytic processes, were positively correlated with exercise and inversely correlated with dietary l-carnitine level. l-carnitine supplementation reduced significantly the RQ from 0.72 to 0.63, and an interaction between dietary l-carnitine and lipid was observed (P <0.03). Our results indicate that an increase in fatty acids (FA) intake may promote FA oxidation, and both carnitine and exercise might influence the regulation of FA oxidation selectivity.