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Dry Matter Intake (dry + matter_intake)
Selected AbstractsIs the intrinsic potassium content of forages an important factor in intake regulation of dairy cows?JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 4 2009F. Leiber Summary Hay from intensively managed grassland with high nutrient density and digestibility containing 29 g potassium/kg dry matter (DM) and hay from an alpine pasture, clearly lower in energy, digestibility and potassium (12 g/kg DM) were offered as sole feeds to 18 lactating dairy cows following a change-over arrangement within three periods of 21 days each (schedule either alpine-lowland-alpine or lowland-alpine-lowland hay). Faeces and urine were quantitatively collected over 7 days. Dry matter intake was similar and neutral detergent fibre (NDF) intake was higher with alpine than with lowland hay (1.57 kg/100 kg vs. 1.43 kg/100 kg body weight). Potassium intake was approximately three times lower with alpine than with lowland hay. Urinary water output was closely correlated with potassium intake. It was also correlated with DM intake but only in animals receiving lowland hay, while it remained independent from intake when alpine hay was fed. Plasma osmolality was lower when alpine hay was fed. As energy requirements were not covered with either diet, the lower NDF intake with lowland hay was assumed to have been caused by higher ruminal osmolality because of the higher intrinsic potassium concentrations of this hay type. Further studies are necessary to determine potassium levels critical for feed intake. [source] Effect of supplementation of garlic powder on rumen ecology and digestibility of nutrients in ruminantsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2008Metha Wanapat Abstract BACKGROUND: The present study investigated the effect of garlic powder (GAP) supplementation on rumen fermentation pattern, nutrient digestibility and intake in ruminants fed on straw as a roughage source. RESULTS: Dry matter intake and apparent digestibility of nutrients were similar among treatments. The apparent digestibility of crude protein tended to be higher in cattle supplemented with GAP compared to those fed without GAP (P = 0.08). Ruminal populations of protozoa and bacteria were decreased, as influenced by GAP supplementation. Ruminal pH and NH3 -N were similar among treatments, while blood urea nitrogen tended to be decreased (P < 0.05). Total volatile fatty acids (VFAs) were not affected by GAP supplementation but individual VFAs were significantly different (P < 0.05), especially C3; meanwhile, C2:C3 ratio was reduced by GAP supplementation (P < 0.05). In addition, N balances were significantly increased as level of GAP supplementation increased and was highest at 120 g d,1 GAP. CONCLUSION: Results of this study suggest that feeding of GAP at 80 g d,1 with urea-treated rice straw could enhance ruminal propionate production and thus lower C2:C3 ratio, decreasing the protozoal population, as well as increasing N retention and absorption in ruminants. Copyright © 2008 Society of Chemical Industry [source] Do endogenous seasonal cycles of food intake influence foraging behaviour and intake by grazing sheep?FUNCTIONAL ECOLOGY, Issue 5 2000G. R. Iason Abstract 1.,Large herbivores living in temperate regions show different degrees of seasonal biological variation, including voluntary food intake (VFI). The decline of VFI in winter has been hypothesized to be an evolved response to lower food availability or quality, which can act as an internal constraint on food intake. 2.,The hypotheses were tested that (i) animals that have a greater inherent seasonal variation of VFI, measured indoors under ad libitum conditions, would also have a greater seasonal variation in intake and grazing behaviour under field conditions, and (ii) greater seasonal variation in intake and grazing behaviour under field conditions would be expressed at a higher level of food availability. 3.,The intake and grazing behaviour in summer and winter, of three breeds of sheep, were compared at two levels of food availability (at pasture heights of 3·7 and 5·4 cm). The breeds were known to have contrasting degrees of seasonal variation in food intake when fed ad libitum; the VFI of the Shetland (SH) and Scottish Blackface (BF) sheep varies greatly between seasons whereas that of the Dorset Horn (DH) is less seasonally variable. 4.,All three breeds consistently increased their rates of biting and duration of grazing activity in the winter, taking many more smaller bites each day than in the summer, and both digestibility and intake were lower in winter than in summer. 5.,Contrary to expectation, the DH ewes had the highest seasonal difference of dry matter intake at pasture, whereas the SH breed had the lowest variation of intake between seasons. 6.,This experiment provides no evidence that differences between seasons in intake and foraging behaviour in the field vary with the animals' degree of endogenous seasonal variation in VFI. Variation between seasons was consistent at both levels of resource availability, suggesting that it resulted from seasonal changes in food quality (digestibility) rather than biomass availability. It is not easy to extrapolate from laboratory feeding studies, where animals' own physiological constraints apply, to foraging ecology in the field, where constraints imposed by the environment may be more important. [source] Feed and feeding quality of imported grass hays as evaluated by newly proposed gradesGRASSLAND SCIENCE, Issue 2 2007Yoshitsugu Niwa Abstract In conjunction with investigating the quality of imported grass hays, the present study set out to develop an evaluation standard. A total of 123 hay samples were tested: 70 of timothy hay, 23 of sudangrass hay, 20 of oat hay and 10 of bermudagrass hay. Crude protein content, nitrogen cell wall free extract (NCWFE) content, Oa (organic a fraction in cell wall, non-lignified portion of cell wall) content and Ob (organic b fraction in cell wall, lignified portion of cell wall) content were measured for each sample, and the values of these were used as the basis for the determination of digestible carbohydrate content and dry matter intake (DMI). The variation in crude protein, NCWFE, Oa and Ob content within each grass species was large. The coefficients of variation for the chemical composition of all 123 samples were 24.9% for crude protein, 37.4% for NCWFE, 30.7% for Oa and 11.0% for Ob. Because variation in composition was large, variations in digestible carbohydrate content and DMI within each species were also large. On the basis of the mean values of chemical composition, it was determined that the harvesting period was after the flowering stage. Evaluation standards were set using a five-point scale (5, excellent; 4, good; 3, medium; 2, low; 1, poor), based on the 123 samples tested in the present study, using the mean values and standard deviations of chemical parameters, digestible carbohydrate content and DMI. Consequently, in assessing DMI (per bodyweight of 600 kg), a grade of 5 was given for values of 14.3 kg or higher, 4 for values between 11.5 and 14.3 kg, 3 for values between 8.7 and 11.5 kg, 2 for values between 5.9 and 8.7 kg, and 1 for values lower than 5.9 kg. [source] Genetic parameters for dry matter, energy and protein intake, and their relationships with performance and carcass traits in Japanese Black cattleJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 1 2009M.A. Hoque Summary Genetic parameters for feed intake and performance traits of 514 bulls and carcass traits of 22 099 of their progeny, and the relationships of measures of feed intake with performance and carcass traits were estimated. Feed intake traits were dry matter intake (DMI), concentrate intake (CONI), roughage intake, ratio of roughage intake to DMI, metabolizable energy intake (MEI) and digestible crude protein intake (DCPI). Performance traits included daily gain, metabolic weight, live weight at the end of test, dry matter conversion ratio and residual feed intake. Progeny carcass traits were carcass weight, percentage of meat yield, rib eye area (REA), subcutaneous fat, marbling score, meat colour (MCS), fat colour (FCS) and meat quality grade. All the feed intake and performance traits were moderately heritable. The heritabilities for REA and MCS were moderate, and that for FCS was low, while those for the other carcass traits were high. Selection against DMI, CONI and DCPI would reduce excessive intake of feed, but would have undesirable effects on growth and most of the carcass traits. Selection against MEI would lead to improvements in feed efficiency and growth traits. Selection against DCPI would also improve feed efficiency; however, responses in growth traits would decrease. Results indicate that selection against MEI might be better than any other measures of feed intake to improve feed efficiency with simultaneous improvement in growth and most of the carcass traits. [source] ORIGINAL ARTICLE: Ileal endogenous amino acid flow of broiler chickens under high ambient temperatureJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010A. F. Soleimani Summary High environmental temperature has detrimental effects on the gastrointestinal tract of poultry. An experiment was conducted to determine the effect of acute heat stress on endogenous amino acid (EAA) flow in broiler chickens. A total of 90, day-old broiler chicks were housed in battery cages in an environmentally controlled chamber. Chicks were fed a nitrogen-free diet on day 42 following either no heat exposure (no-heat) or 2 weeks exposure to 35 ± 1 °C for 3 h from days 28 to 42 (2-week heat) or 1 week exposure to 35 ± 1 °C for 3 h from days 35 to 42 (1 week heat). The most abundant amino acid in the ileal flow was glutamic acid, followed by aspartic acid, serine and threonine in non-heat stressed group. The EAA flow in 1-week heat and 2-week heat birds were significantly (p < 0.05) higher than those under no heat exposure (14682, 11161 and 9597 mg/kg of dry matter intake respectively). Moreover, the EAA flow of 2-week heat group was less than 1-week heat group by approximately 36%. These observations suggest that the effect of heat stress on EAA flow is mostly quantitative; however, heat stress may also alter the content of EAA flow qualitatively. [source] Supplementation of xylanase and phospholipase to wheat-based diets for weaner pigsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 9-10 2005G. Diebold Summary The effects of supplementing a wheat-based diet for weaner pigs with exogenous xylanase and phospholipase on ileal and faecal nutrient digestibilities and on the level of microbial metabolites in ileal digesta were examined. Fourteen piglets, weaned at 11 days, were fitted with a simple T-cannula at the distal ileum. The pigs were offered a control diet or diets supplemented with xylanase and phospholipase individually or in combination, in a two period crossover design. The combination of xylanase and phospholipase tended to increase the ileal recovery of the amino sugar galactosamine, whereas the concentration expressed in mg/kg dry matter intake of glucosamine was slightly decreased (p < 0.10). There was neither an effect of enzyme supplementation on ileal and faecal digestibility of the other nutrients and energy, nor was there an effect on pH and on the level of microbial metabolites in ileal digesta. However, an increase in ileal and faecal nutrient and energy digestibility with increasing age was observed. The ileal and faecal digestibility coefficients (except for ether extract) were significantly (p < 0.05) higher in experimental period I than in period II. These higher values may be attributed to a lower feed intake during period I. Since a lower level of feed intake is generally associated with a slower rate of passage and a longer retention time of digesta, a positive impact on digestion and absorption of nutrients can be assumed, which, on the other hand, limits the potential of additional enzyme effects. [source] Comparison of feed preference and digestion of three different commercial diets for cats and ferretsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 3-6 2005S. Gy. Summary Diet preference and digestibility experiments were conducted using a total of 10 cats and 10 ferrets. The composition of the three different kinds of dry cat feed was as follows (each data are given in dry matter, DM): (i) normal diet (N): 95.3% DM, 33.7% crude protein (CP), 20.4% ether extract (EE), 37.6% nitrogen-free extract (NFE); (ii) ,light diet' (L): 94.2% DM, 31.6% CP, 10.7% EE, 52.2% NFE; (iii) ,veterinary diet' (D): 94.57% DM, 38.7% CP, 9.6% EE, 47.2% NFE. During the period of the preference test, the average daily dry matter intake (calculated with the mean of the three diets: 94.7% DM) was 98.0, 15.0 and 16.7 g DM in cats and 25.0, 7.3 and 8.1 g DM in ferrets. The preference rates of the three different diets, expressed in percentage of their total consumption, were as follows: 60.4% N (54.4 g DM), 12.4% L (12.1 g DM) and 27.2% D (26.6 g DM) in cats, and 46.2% N (11.6 g DM), 29.9% L (7.5 g DM) and 23.9% D (6.0 g DM) in ferrets. This indicates that cats and ferrets have a clear preference for diets of higher fat content. In all three diets, the digestibility of CP was significantly (p < 0.05) lower (70.1 ± 5.4 vs. 75.9 ± 5.8) while that of EE was significantly (p < 0.05) higher (95.6 ± 1.5 vs. 89.4 ± 5.3) in ferrets than in cats. The average digestible/metabolizable energy (DE/ME) ratio of feeds turned to be 95.6% for cats and 90.6% for the ferrets. From the data one can conclude that the ferret cannot be used as a model animal for cats either for preference or digestibility studies. [source] Effect of protein : energy ratio in milk replacers on growth performance of goat kidsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5-6 2002K-H. YEOM Two separate experiments were carried out to establish the effects of the protein : energy ratio in milk replacers on growth performance, plasma lipid concentrations and fatty acid composition in adipose tissue of male goat kids. In the first experiment there were 211 3-day- old goat kids and in the second experiment there were 121 kids aged 3,7 days. The animals were fed ad libitum for a period of 4 weeks on milk replacers containing either 11.5 or 9.5 g crude protein/MJ metabolizable energy. In essence, protein was exchanged with fat on a weight basis. Milk concentrations were increased from 160 to 190 g/l in experiment 1, from 150 to 180 g/l in experiment 2. There were significant increases in body weight and feed intake when the milk replacer with high protein : energy ratio was fed. Group mean average daily weight gain was 168 and 203 g for the groups with low and high dietary protein : energy ratio in experiment 1; for experiment 2 the values were 139 and 160 g. Average dry matter intake was 18 and 14% higher for the diet with high protein : energy ratio in experiments 1 and 2, respectively. There was no change in either feed conversion (feed : gain ratio) or energy conversion (weight gain : energy intake ratio). There were no consistent diet effects on plasma lipid concentrations. Dietary fatty acid composition was reflected by that of adipose tissue. The milk replacer with high protein : energy ratio produced a small increase in the contents of myristic and palmitic acid in adipose tissue. [source] Influence of ciliate protozoa on biochemical changes and hydrolytic enzyme profile in the rumen ecosystemJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2002A. Santra Aims:,To assess the effect of presence or absence of rumen protozoa on fermentation characteristics and enzyme profile in growing lambs. Methods and Results:,Weaner lambs (G1, G2, G3, G4, G5 and G6 groups) were defaunated by oral administration of sodium laurel sulphate (at 8 g 100 kg,1 body weight). The lambs of G4, G5 and G6 groups were refaunated. The roughage and concentrate ratio in the diet of G1 and G4, G2 and G5, and G3 and G6 were 50:50 (R1), 65:35 (R2) and 80:20 (R3), respectively. Daily dry matter intake was similar in defaunated and faunated lambs. However, digestibility of organic matter (OM), cellulose and gross energy were lower in defaunated lambs while crude protein (CP) digestibility was similar in both defaunated and faunated lambs. The rumen pH and NH3 -N were lower (P < 0·01) while TVFA, total-N and TCA-ppt-N were higher (P < 0·01), in defaunated lambs. Ruminal activity of carboxymethyl cellulase was lower (P < 0·01) in defaunated lambs and amylase, xylanase, protease and urease were similar in faunated and defaunated lambs. Nutrient utilization, rumen metabolites and ciliate protozoal count were higher, whereas digestibility of fibre fractions was lower in high rather than low concentrate fed lambs. The rumen protozoa present before defaunation were B-type and the protozoa which re-established on refaunation were also B-type. Conclusions:,Absence of ciliate protozoa decreased nutrient digestibility and increased ruminal TVFA and total-N with lower NH3 -N concentration, indicating better energy and protein utilization in defaunated lambs. Significance and Impact of the Study: Defaunation improved energy and protein utilization in lambs. [source] Estimates of basal ileal endogenous losses of amino acids by regression analysis and determination of standardised ileal amino acid digestibilities from casein in newly weaned pigs,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2008Meike Eklund Abstract BACKGROUND: This study was carried out to estimate basal ileal endogenous crude protein (CP) and amino acid (AA) losses (IAALB) in newly weaned pigs by regression analysis from apparent ileal digestible and the corresponding total dietary contents of CP and AA in order to obtain standardised ileal digestibilities (SID) of CP and AA originating from casein. A total of fourteen 3-week-old barrows were fitted with simple T cannulas at the distal ileum and were fed six diets with two pigs per diet in 4 weekly repeated measurements. Corn starch-based diets containing six graded levels of CP from casein with 90, 155, 220, 285, 350 and 415 g kg,1 CP (as-fed basis) were formulated. RESULTS: Linear relationships (P < 0.001) between apparent ileal digestible and total dietary contents of CP and AA (g kg,1 dry matter intake (DMI)) exist for CP and all AA in the range of 90,220 g kg,1 CP content in the diet. The IAALB extrapolated from the range of 90,220 g kg,1 CP content are different from zero (P < 0.001 to P = 0.019) except for tryptophan (P = 0.220). Based on regression analysis in the range of 90,220 g kg,1 CP, estimates of IAALB, expressed as g kg,1 DMI, and SID of CP and AA in casein (in parentheses, %) were as follows: CP 9.3 (98.0); arginine 0.4 (98.9); histidine 0.2 (98.5); isoleucine 0.2 (98.1); leucine 0.5 (99.2); lysine 0.4 (99.0); methionine 0.1 (99.1); phenylalanine 0.4 (99.9); threonine 0.6 (97.8); tryptophan 0.1 (96.2); valine 0.4 (98.5). CONCLUSION: The IAALB and SID of CP and AA originating from casein in newly weaned pigs are in close agreement with values obtained in grower finisher pigs. Copyright © 2007 Society of Chemical Industry [source] Effect of breed type, housing and feeding system on performance of growing pigs managed under organic conditionsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2007Hilary RC Kelly Abstract BACKGROUND: There is a need for information on the performance and carcass quality of pigs under different organic management systems. This study compared Duroc-sired progeny from three maternal breed types when kept either at pasture or in housing with an outdoor run and offered ad libitum concentrate either alone or with fodder beet or grass/clover silage as additional forage. RESULTS: Liveweight gain, feed intake and the proportion of forages consumed did not differ between genotypes. Carcass fatness of progeny was lowest for a ,modern' genotype (Camborough 12) and highest for a ,traditional' purebred genotype (Saddleback), with a ,crossbred traditional' genotype (Saddleback × Duroc) being intermediate (11.4, 14.3 and 13.4 mm P2 respectively, standard error of mean (SEM) 0.27, P < 0.001). With a cereal-based concentrate available ad libitum, intake of forages was low (<2% of dry matter intake). Although growth rate did not differ between housing systems, daily feed intake was greater at pasture (2.47 vs 2.22 kg meal equivalent, SEM 0.05, P < 0.001), giving poorer feed efficiency (P < 0.01). Pastured animals consumed less additional forage and had a higher killing-out % but similar carcass fatness. CONCLUSION: For organic pig production to be financially sustainable, disadvantages arising from the genotype and/or rearing system chosen need to be offset by a market premium for the pigs produced. Copyright © 2007 Society of Chemical Industry [source] Effect of feeding complete feed block containing Prosopis cineraria leaves and polyethylene glycol (PEG)-6000 on nutrient intake, its utilization, rumen fermentation pattern and rumen enzyme profile in kidsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2005Raghavendra Bhatta Abstract A study was carried out to determine the effect of replacing the cake portion of concentrate mixture with 5 parts polyethylene glycol (PEG)-6000 in a complete feed block (CFB) containing Prosopis cineraria leaves on the performance, rumen fermentation pattern and rumen enzyme profile of kids under an intensive system of rearing. Eighteen weaners of Sirohi goat of similar body weight (16.0 ± 0.5 kg) and age (90 ± 5 days) were divided into three equal groups. They were housed in individual cages in a side open asbestos roof shed with mud floor. All the kids received CFBs containing 50 parts P cineraria leaves and 50 parts concentrate mixture. CFB offered to the first group had high protein (183.8 g kg,1; HP), that offered to the second group had low protein (131.3 g kg,1; LP) and that offered to the third group had low protein (124.7 g kg,1) but contained PEG-6000 (LP-PEG). The concentrate mixtures in LP and LP-PEG were without groundnut cake, whereas in LP-PEG, groundnut cake was replaced by barley and 5 parts PEG-6000 were incorporated. CFBs were similar in their nutritive value except for crude protein (CP). Prosopis leaves utilized in the CFB contained (g kg,1 dry matter) 129.1 CP, 535.5 neutral detergent fibre, 395.8 acid detergent fibre and 222.8 acid detergent lignin. There were significant differences in dry matter intake (g day,1) between HP (1102), LP (1108) and LP-PEG (1194); the trend in Metabolizable energy intake was similar. During the growth trial, LP kids consumed maximum amount of feed (76.91 kg) followed by HP (75.73 kg) and LP-PEG (73.12 kg). However, maximum feed efficiency (feed consumed kg,1 live weight gain) was recorded in LP-PEG kids (9.59) followed by HP (10.64) and LP (11.60). These differences were statistically significant (p < 0.05). Although there was no significant difference in the digestibility of dry matter among the groups, there was significant difference in the digestibility of CP, neutral detergent fibre and acid detergent fibre. The digestibility of CP was 0.591, 0.484 and 0.645, that of neutral detergent fibre was 0.397, 0.308 and 0.499 and that of acid detergent fibre was 0.168, 0.154 and 0.282 in HP, LP and LP-PEG, respectively. Rumen metabolites studied 6 h after feeding revealed that there were significant (p < 0.05) differences in the concentrations of ammonia N, tri-chloro acetic acid precipitable N and total volatile fatty acids among the three groups, but not pH. The rumen enzyme concentrations showed significant (p < 0.05) differences for ,-amylase, whereas the differences were non-significant for CMcase and protease. After 90 days of feeding trial, the maximum weight gain was recorded in LP-PEG (7.62 kg) followed by HP (7.23 kg) and LP (6.53 kg). It can be concluded that, when kids are reared under an intensive system on complete feed blocks containing Prosopis leaves, high protein concentrate can be replaced with a low protein concentrate containing 5 parts PEG, which would not only alleviate the negative effects of tannin but would also spare expensive groundnut protein. Copyright © 2005 Society of Chemical Industry [source] Comparative dry matter intake and nutrient utilisation efficiency in lactating cattle and buffaloesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2003Shyam S Paul Abstract An attempt was made to assess the comparative dry matter intake and nutrient utilisation efficiency of lactating buffaloes and cows based on results obtained from experimental feeding trials conducted in India. Data on dry matter (DM) intake, total digestible nutrient (TDN) intake, digestible crude protein (DCP) intake, body weight or metabolic body size (MBS), body weight change, milk yield or 4% fat-corrected milk (FCM) yield, milk fat percentage and roughage/concentrate ratio in the diet of lactating buffaloes and cows were collected from published reports. The data were processed and analysed to assess the comparative dry matter intake and nutrient utilisation efficiency using suitable statistical analysis models. DM intake was significantly (P,<,0.01) lower in buffaloes (2.57,kg DM per 100,kg body weight or 119.2,g,kg,1 MBS) than in cattle (3.09,kg DM per 100,kg body weight or 132.0,g,kg,1 MBS). Mean gross energetic efficiency (30.53 versus 27.83%; P,<,0.01), gross protein efficiency (45.48 versus 37.06%; P,<,0.01), net energetic efficiency (69.16 versus 64.10%; P,<,0.05) and net protein efficiency (80.15 versus 59.59%; P,<,0.001) were significantly higher in buffaloes than in cattle. Lactating buffaloes consumed significantly less (P,<,0.001) protein (75.69,g DCP) and less (P,<,0.01) energy (695.9,g TDN) than cows (93.89,g DCP, 774.8,g TDN) for production of 1,kg of 4% fat-corrected milk. Buffaloes had higher energy and protein utilisation efficiencies as compared with cattle at similar fat-corrected milk production level, plane of energy and protein nutrition, body size and body weight change. Buffaloes (1.189,kg DM,kg,1 4% FCM) consumed a similar (P,>,0.05) amount of feed dry matter to that of cows (1.267,kg DM,kg,1 4% FCM). However, when DM intake,kg,1 FCM (4%) was compared at constant levels of metabolic body size, fat-corrected milk, body weight change, dietary energy concentration and green forage percentage in the diet, lactating buffaloes consumed significantly less DM,kg,1 FCM yield as compared with cattle. It was concluded that DM intake was lower in lactating buffaloes. Moreover, lactating buffaloes utilised dietary dry matter, energy and protein for milk production more efficiently than cattle. © 2003 Society of Chemical Industry [source] The effect of digesta sampling time and dietary protein source on ileal nitrogen digestibility for the growing rat,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2002Christine A Butts Abstract The effect of time that digesta were collected on the quantity and representativeness of ileal digesta and on the determination of apparent and true ileal nitrogen (N) digestibility for growing rats was investigated. Semi-synthetic diets containing chromic oxide as an indigestible marker were given to 200,g live weight rats for 8 days as a single daily meal. The experimental treatments comprised six diets (lactalbumin, soy protein isolate, wheat gluten, fish, protein-free (PF), enzymically hydrolysed casein (EHC)) and four ileal digesta sampling times (3, 4, 5 and 6,h after the start of feeding). On the eighth day the rats were fed and slaughtered according to treatment, and digesta were sampled from the terminal ileum. Endogenous ileal nitrogen excretion was determined using both the protein-free and peptide alimentation methods. There was a significant (P,,=,0.027) effect of experimental diet averaged across sampling times for chromium recovery (CrRec). The CrRec was higher for the rats fed the PF diet than for the other diets. Responses to sampling time varied significantly (P,<,0.05) among diets for ileal digesta weight (IDW), nitrogen/chromium (N/Cr) ratio, ileal digesta weight relative to dry matter intake (IDW/DMI), CrRec, N flow, apparent N digestibility and true N digestibility (determined using the protein-free method). The optimal digesta sampling times for each of the diets were 3,h for PF, EHC, lactalbumin and fish and 4,h for soy protein isolate and wheat gluten. Consequently, 3 or 4,h after the start of feeding is recommended as the optimum ileal digesta sampling time for most purified protein sources when fed to the growing rat as a single daily meal. © 2002 Society of Chemical Industry [source] Winter browsing on Alaska feltleaf willow twigs improves leaf nutritional value for snowshoe hares in summerOIKOS, Issue 1 2003John P. Bryant In boreal forests, browsing by mammals on winter-dormant twigs increases leaf nitrogen, leaf greenness, and leaf size. This suggests browsing reduces competition among meristems for mineral nutrients, and in particular, competition for nitrogen. Winter browsing also reduces the shoot carbohydrate reserves used by leaves to produce condensed tannin. These effects of winter browsing are predicted to improve the nutritional value of leaves for mammals because they increase the mass of digestible nitrogen in leaves. This hypothesis was tested using Alaska feltleaf willow and the snowshoe hare as the experimental system. Six in vivo indicators of leaf nutritional quality were used to compare leaves from winter-browsed plants with leaves from unbrowsed plants. The indicators used were dry matter intake, nitrogen intake, condensed tannin intake, dry matter digestibility, apparent digestibility of nitrogen and nitrogen retention. The results obtained were in agreement with the above hypothesis. In early summer, at the time snowshoe hares and other northern herbivores reproduce, hares fed leaves from browsed plants consumed more nitrogen, digested more of the nitrogen they consumed, and retained more of the nitrogen they digested than did hares fed leaves from unbrowsed plants. The high nitrogen content and low tannin content of leaves from browsed plants may explain this browsing caused increase in leaf nutritional value. How these positive effects of winter browsing on snowshoe hare nutrition at the time of reproduction might affect hare population dynamics are briefly discussed. [source] Digestion in the common marmoset (Callithrix jacchus), a gummivore,frugivoreAMERICAN JOURNAL OF PRIMATOLOGY, Issue 12 2009Michael L. Power Abstract Wild common marmosets (Callithrix jacchus) feed on fruits, insects, and gums, all of which provide different digestive challenges. Much of the ingested mass of fruits consists of seeds. In general, seeds represent indigestible bulk to marmosets and could inhibit feeding if they are not eliminated rapidly. In contrast, gums are ,-linked polysaccharides that require microbial fermentation. Their digestion would benefit from an extended residence time within the gut. Earlier research found that mean retention time (MRT) for a liquid digestive marker (cobalt EDTA) was significantly longer than MRT for a particulate marker (chromium-mordanted fiber), suggesting that common marmosets preferentially retain liquid digesta. We conducted two four-day-long digestion trials on 13 individually housed adult common marmosets fed a single-item, purified diet in order to examine the relations among MRT of cobalt EDTA and chromium-mordanted fiber, food dry matter intake (DMI), and apparent digestibility of dry matter (ADDM). We compared the MRT values with the data from the previous study mentioned above and a study using polystyrene beads. There were no significant correlations among MRT, ADDM, or DMI, although increases in DMI between trials were associated with decreases in MRT. ADDM was consistent within individuals between trials; but the mean values ranged from 75.0 to 83.4% among individuals. We found no difference in MRT between the liquid (17.5±1.6,hr) and particulate (17.9±1.4 hr) markers. Although these values were not significantly different than found previously, the MRT for chromium-mordanted fiber tended to be longer. This probably reflects the relatively small size of the chromium-mordanted fiber particles used in this study. An inverse relationship between particle size and MRT was evident; the mean MRT of polysterene beads, the largest marker, was only 8.3±1.5,hr. Marmosets appear to retain liquids and small particles within the gut longer than large particles. Am. J. Primatol. 71:957,963, 2009. © 2009 Wiley-Liss, Inc. [source] Polymorphisms in the STAT6 gene and their association with carcass traits in feedlot cattleANIMAL GENETICS, Issue 6 2009G. Rincon Summary Identification of the genes and polymorphisms underlying quantitative traits, and understanding how these genes and polymorphisms affect economic traits, are important for successful marker-assisted selection and more efficient management strategies in commercial cattle populations. Signal transducer and activator of transcription 6 (STAT6) gene is tightly connected to IL-4 and IL-13 signalling and plays a key role in TH2 polarization of the immune system. In addition, STAT6 acts as a mediator of leptin signalling and has been associated with body weight regulation. The objective of this study was to determine if SNPs within the bovine STAT6 gene are associated with economically important traits in feedlot cattle. The approach consisted of resequencing STAT6 using a panel of DNA from unrelated animals of different beef breeds. Specifically, 16 kb of STAT6 was resequenced in 47 animals and the process revealed 39 SNPs. From the 39 SNPs, a panel of 15 tag SNPs was genotyped in 1500 beef cattle samples with phenotypes to perform a marker-trait association analysis. Among the 15 tag SNPs, five and six were polymorphic in Bos taurus and Bos indicus respectively. An association analysis was performed between the 15 tag SNPs and 14 performance and production traits. SNP ss115492459:C > A, ss115492461:A > G and ss115492458:G > C were significantly associated with back fat, calculated yield grade, cutability, hot carcass weight, dry matter intake, days on feed, back fat rate and average daily gain. These three SNPs were present in all Bos taurus beef breeds examined. Our results provide evidence that polymorphisms in STAT6 are associated with carcass and growth efficiency traits, and may be used for marker-assisted selection and management in feedlot cattle. [source] Quantitative trait loci with effects on feed efficiency traits in Hereford × composite double backcross populationsANIMAL GENETICS, Issue 6 2009G. C. Márquez Summary Two half-sib families of backcross progeny were produced by mating F1 Line 1 Hereford (L1) × composite gene combination (CGC) bulls with L1 and CGC cows. Feed intake and periodic weights were measured for 218 backcross progeny. These progenies were genotyped using 232 microsatellite markers that spanned the 29 BTA. Progeny from L1 and CGC females was analysed separately using composite interval mapping to find quantitative trait loci (QTL) affecting daily dry matter intake (DMI), average daily gain (ADG), feed conversion (FCR) and residual feed intake (RFI). Results from both backcrosses were pooled to find additional QTL. In the backcross to L1, QTL were detected for RFI and DMI on BTA11, FCR on BTA16, and ADG on BTA9. In the backcross to CGC, QTL were detected for RFI on BTA10, FCR on BTA12 and 16 and ADG on BTA15 and 17. After pooling, QTL were detected for RFI on BTA 2, 6, 7, 10, 11, 13 and 16; for FCR on BTA 9, 12, 16, 17 and 21; for ADG on BTA 9, 14, 15, 17; and for DMI on BTA 2, 5, 6, 9, 10, 11, 20 and 23. [source] Identification of polymorphisms influencing feed intake and efficiency in beef cattleANIMAL GENETICS, Issue 3 2008E. L. Sherman Summary Feed efficiency is an economically important trait in beef cattle. Net feed efficiency, measured as residual feed intake (RFI), is the difference between actual feed intake and the predicted feed intake required for maintenance and gain of the animal. SNPs that show associations with RFI may be useful quantitative trait nucleotides for marker-assisted selection. This study identified associations between SNPs underlying five RFI QTL on five bovine chromosomes (BTA2, 5, 10, 20 and 29) with measures of dry matter intake (DMI), RFI and feed conversion ratio (FCR) in beef cattle. Six SNPs were found to have effects on RFI (P < 0.05). The largest single SNP allele substitution effect for RFI was ,0.25 kg/day located on BTA2. The combined effects of the SNPs found significant in this experiment explained 6.9% of the phenotypic variation of RFI. Not all the RFI SNPs showed associations with DMI and FCR even though these traits are highly correlated with RFI (r = 0.77 and r = 0.62 respectively). This shows that these SNPs may be affecting the underlying biological mechanisms of feed efficiency beyond feed intake control and weight gain efficiency. These SNPs can be used in marker-assisted selection but first it will be important to verify these effects in independent populations of cattle. [source] Factors affecting methane production and mitigation in ruminantsANIMAL SCIENCE JOURNAL, Issue 1 2010Masaki SHIBATA ABSTRACT Methane (CH4) is the second most important greenhouse gas (GHG) and that emitted from enteric fermentation in livestock is the single largest source of emissions in Japan. Many factors influence ruminant CH4 production, including level of intake, type and quality of feeds and environmental temperature. The objectives of this review are to identify the factors affecting CH4 production in ruminants, to examine technologies for the mitigation of CH4 emissions from ruminants, and to identify areas requiring further research. The following equation for CH4 prediction was formulated using only dry matter intake (DMI) and has been adopted in Japan to estimate emissions from ruminant livestock for the National GHG Inventory Report: Y = ,17.766 + 42.793X , 0.849X2, where Y is CH4 production (L/day) and X is DMI (kg/day). Technologies for the mitigation of CH4 emissions from ruminants include increasing productivity by improving nutritional management, the manipulation of ruminal fermentation by changing feed composition, the addition of CH4 inhibitors, and defaunation. Considering the importance of ruminant livestock, it is essential to establish economically feasible ways of reducing ruminant CH4 production while improving productivity; it is therefore critical to conduct a full system analysis to select the best combination of approaches or new technologies to be applied under long-term field conditions. [source] The effect of dietary ratios of corn silage and alfalfa hay on carbohydrate digestion and retention time of feed particles in the gastrointestinal tract of steersANIMAL SCIENCE JOURNAL, Issue 5 2009Taketo OBITSU ABSTRACT Four Holstein steers fitted with duodenal cannula were used in a 4 × 4 Latin square design to investigate the effect of the combination of corn silage (CS) and alfalfa hay (AH) in different ratios on the ruminal and intestinal digestion of carbohydrates and feed particle passage rate. Steers were fed mixed diets containing both CS and AH in ratios of 80:20, 60:40, 40:60 and 20:80 on a dry matter basis at 95% of ad libitum feed intake. The increase of AH proportion in diets increased dry matter intake and ruminal digestion of dry matter, non-fiber carbohydrate, neutral and acid detergent fiber linearly. Ruminal digestibility of neutral detergent fiber showed a quadratic response, and total digestibility increased linearly with increasing AH proportion. Digestibility of acid detergent fiber in the rumen was not affected by the dietary treatments, but the total tract digestibility increased as the AH proportion increased. Mean retention time of feed particles in total compartment increased when the AH proportion increased from 20% to 60%, but decreased with further increase of the AH proportion. These results indicate that moderate combinations of CS and AH have an associative effect on ruminal fiber digestion, modifying particle movement in the rumen. [source] Effects of diets containing alfalfa hay or barley flour mixed alfalfa silage on feeding behavior, productivity, rumen fermentation and blood metabolites in lactating cowsANIMAL SCIENCE JOURNAL, Issue 4 2009Ali-Akbar KHADEM ABSTRACT The effects of barley flour on the fermentation parameters of alfalfa silage and on the productivity of dairy cows were investigated. Alfalfa forage was ensiled either with or without barley flour. Barley flour was soaked in water for 24 h before being mixed with alfalfa (12 kg: 100 kg dry matter bases) at ensiling. Eighteen multi-parous cows were assigned to three equal treatment groups using a completely randomized design. Three isocaloric and isonitrogenous total mixed rations containing alfalfa hay, ordinary alfalfa silage or barley flour mixed alfalfa silage were then prepared. The concentrations of ammonia nitrogen, acetic acid and butyric acid were lower in barley flour mixed alfalfa silage compared to that in ordinary alfalfa silage but the concentration of lactic acid was lower in the ordinary alfalfa silage. Feeding behavior, milk yield and composition, ruminal fermentation and blood metabolites were measured. Although dry matter intake and milk production were not affected, the effect of preparation of alfalfa influenced feeding behavior and rumen fermentation parameters. Cows on alfalfa silage diets spent longer ruminating compared to those fed alfalfa hay. The ruminal ammonia nitrogen and blood urea were affected by ensiling (alfalfa hay versus alfalfa silages) while both parameters were lower in cows fed on barley flour mixed alfalfa silage than those fed on ordinary silage. Although similar blood glucose was recorded for cows fed on alfalfa silages, it was higher in cows fed on alfalfa hay. It is concluded that the addition of barely flour when making alfalfa silage may improve both the fermentation process during ensilage and the ruminal ammonia nitrogen utilization with no significant effects on productivity. [source] Effects of maize (Zea mays L.) silage feeding on dry matter intake and milk production of dairy buffalo and cattle in Tarai, NepalANIMAL SCIENCE JOURNAL, Issue 4 2009Yoshiaki HAYASHI ABSTRACT To identify the effects of whole crop maize silage (MS) as a substitute for rice straw (RS) on feed intake and milk production of mid-late lactating buffalo and cattle in Tarai, Nepal, eight Murrah and eight Jersey-Hariana were fed the basal diet, RS (ad libitum) with concentrate (0.68% of bodyweight [BW] on a dry matter [DM] basis). A 4 × 4 Latin square design experiment was conducted in each animal species with graded levels of MS substitution for RS (0%, T1; 33%, T2; 67%, T3 and 100%, T4). The MS had higher digestibility and total digestible nutrient (TDN) than RS. The DM intake per BW of the both species was highest in T3. The substitution of MS for RS increased the crude protein intake and the TDN intake in the both species. Although the buffalo showed the highest milking performance in T4, the cattle showed no significant differences in their milking performance among the treatments. The substitution of MS for RS improved the feed intake and milk production in the buffalo. On the other hand, the milk yield was not raised in the cattle, though the feed intake was increased by the substitution. [source] Effect of cyclodextrin diallyl maleate on methane production, ruminal fermentation and microbes in vitro and in vivoANIMAL SCIENCE JOURNAL, Issue 1 2004Zeenat Ara LILA ABSTRACT Effects of ,-cyclodextrin diallyl maleate (CD-M) on methane production, ruminal fermentation and digestibility were studied both in vitro and in vivo. In in vitro study, diluted ruminal fluid (30 mL) was incubated anaerobically at 38°C for 6 and 24 h with or without CD-M using hay plus concentrate (1.5:1) as a substrate. The CD-M was added at different concentrations (0, 1.25, 2.5, 5.0 and 7.5 g/L). The pH of the medium and numbers of protozoa were not affected by the addition of CD-M. Total volatile fatty acids were increased and ammonia-N was decreased, molar proportion of acetate was decreased and propionate was increased (P < 0.05) by CD-M. Methane was inhibited (P < 0.05) by 14,76%. The effect of CD-M on methane production and ruminal fermentation was further investigated in vivo using four Holstein steers in a cross-over design. The steers were fed Sudangrass hay and concentrate mixture (1.5:1) with or without CD-M (2% of feed dry matter) as a supplement. Ruminal proportion of acetate tended to decrease and that of propionate was increased (P < 0.05) 2 h after CD-M dosing. Total viable counts, cellulolytic, sulfate reducing, acetogenic bacteria and protozoa were unaffected while methanogenic bacteria were decreased (P < 0.05) by CD-M. The plasma concentration of glucose was increased, whereas that of urea-N was decreased (P < 0.05). Methane was inhibited (P < 0.05) from 36.4 to 30.1 L/kg dry matter intake by the addition of CD-M. Apparent digestibilities of dry matter and neutral detergent fiber were not affected while that of crude protein was increased (P < 0.05) in the medicated steers. These data suggested that dietary supplementation of CD-M decreased methane production and improved nutrient use. [source] Clinical acidosis in a Gippsland dairy herdAUSTRALIAN VETERINARY JOURNAL, Issue 6 2005E. BRAMLEY Objective: To report on spontaneous clinical and subclinical acidosis in a large dairy herd, to evaluate the diets and feeding strategies involved, and to report on measures of rumen function in the cows affected. Design: A Gippsland dairy herd was sampled as part of a wider randomised cross-sectional study that examined the prevalence, risk factors for, and effects of, acidosis on rumen function of dairy cattle. Three herds on the farm were involved in the study: the transition herd (cows 3 weeks prior to calving), the very fresh lactating herd (1
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