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1.
Four Nili-Ravi buffalo calves (100 ± 4 kg) were used in 4 × 4 Latin Square Design to evaluate the influence of varying ruminally degradable protein (RDP) to ruminally undegradable protein (RUP) ratio on dry matter intake (DMI), digestibility and nitrogen (N) metabolism. Four experimental diets A, B, C and D were formulated to contain RDP:RUP of 70:30, 65:35, 60:40 and 55:45, respectively. The calves were fed ad libitum. Dry matter intake by calves fed C diet was higher (P < 0.05) than those fed D diet and lower (P < 0.05) than calves fed A diet, however, it was similar to those fed B diet. There was a linear decrease (P < 0.01) in DMI with decreasing the RDP to RUP ratio. Similar trend was noticed in crude protein (CP) intake. Neutral detergent fiber (NDF) intake was significantly different across all treatment. The decrease in CP and NDF intake was due to decreasing trend of DMI. Dry matter (DM) digestibility in calves fed A and B diets was higher (P < 0.05) than those fed C and D diets. A linear decrease (P < 0.01) in DM digestibility was observed with decreasing the RDP to RUP ratio. Crude protein digestibility remained unaltered across all treatments. Neutral detergent fiber digestibility was higher in calves fed A and B diets than those fed C and D diets. Higher NDF digestibility in calves fed A and B diets was due to higher level of dietary RDP that might resulted in higher ruminal ammonia concentration which stimulate activity of cellulytic bacteria and ultimately increased NDF digestibility. The N retention (g/d) was similar among the calves fed B, C and D diets, however, it was higher (P < 0.05) than those fed A diet. Decreasing the RDP to RUP ratio resulted in linear increase (P < 0.01) in N retention. The N retention, as percent of N intake was significantly different across all treatments. Decreasing RDP to RUP ratio resulted in linear increase (P < 0.01) in N retention, as percent of N intake. A similar trend was noticed in N retention, as percentage of N digestion. Blood urea nitrogen (BUN) concentration in calves fed B diet was higher (P < 0.05) than those fed D diet and was lower (P < 0.05) than those fed A diet, however, it was not different from calves fed C diet. Decreasing dietary RDP to RUP ratio resulted in linear decrease (P < 0.05) in BUN concentrations. The decrease in BUN concentration was because of decreasing level of dietary RDP. The N retention can be increased by decreasing RDP to RUP ratio in the diet of growing buffalo calves and diet containing RDP to RUP ratio 55:45 is considered optimum regarding N retention in buffalo calves.  相似文献   

2.
The concentration of condensed tannins (CT) in sulla (Hedysarum coronarium L.) is moderate and overall regarded as beneficial. However, the intake of this forage can reduce diet digestibility, particularly during flowering phase. An experiment was run to assess the effect of CT on feeding behaviour, intake, diet digestibility and performance of dairy sheep rotationally grazing sulla at flowering phase. Twenty-four late-lactating sheep were blocked in two homogeneous groups and submitted to the following treatments: i) twice daily drenching with 200 g/day of a 50% w/v water solution of an anti-tannic substance, polyethylene glycol, group PEG; ii) twice daily drenching with 200 g/day of water, group CON (Control group). All the sheep rotationally grazed as a flock two sulla plots from April to June (8 weeks in total). Sward height, herbage mass, botanical and chemical composition of the herbage were measured at the beginning and the end of each grazing period. The feeding behaviour (3 sheep per group) was continuously monitored for 24 h in 6 weeks using the IGER behaviour recorders. Herbage DM intake (DMI), dietary DM digestibility (DMD) and apparent CP digestibility (CPD) were estimated on 8 sheep per group by the n-alkane method. On average, PEG group had longer total grazing (503 ± 12 vs 460 ± 12 min, P < 0.05) and eating time (425 ± 13 vs 391 ± 13 min, P < 0.07) than CON group. Moreover PEG group showed shorter inter-meal intervals (41 ± 3 vs 52 ± 3, min, P < 0.05) and higher number of daily meals than CT-exposed group (24 ± 1 vs 19 ± 1 min, P < 0.01). The herbage DMI was not affected by the treatment whereas DMD (74.60 ± 3.48 vs 58.30 ± 3.01%), and CPD (60.14 ± 4.83 vs 38.21 ± 4.83%) were both increased by PEG administration (P < 0.05) confirming the negative effect of sulla CT on these variables. Milk yield tended to be higher in PEG than CON (1331 ± 45 vs 1205 ± 59 ml, P < 0.11). Milk protein content was similar between groups while milk fat content was higher in CON than PEG ewes (6.61 ± 0.15 vs 6.11 ± 0.15%, P < 0.05), being the reverse true for milk urea (46.04 ± 1.27 vs 53.04 ± 0.76%, P < 0.001). To conclude, this experiment shows that when sulla is grazed at flowering as monoculture, dietary CT can exert negative effects on DM and CP apparent digestibility, in this study partially counterbalanced by a better metabolic utilisation of the nutrients up-taken.  相似文献   

3.
Equid digestion is often conceptualized as a high‐throughput/low‐efficiency system, in particular compared with ruminants. It is commonly assumed that ruminants have an advantage when resources are limited; the effect of low food intake on digestive physiology of horses has, however, not been explored to our knowledge. We used four adult ponies [initial body mass (BM) 288 ± 65 kg] in two subsequent trials with grass hay‐only diets [in dry matter (DM): hay1, mid‐early cut, crude protein (CP) 10.5%, neutral detergent fibre (NDF) 67.6%; hay2, late cut, CP 5.8%, NDF 69.5%], each fed subsequently at four different dry matter intake (DMI) levels: ad libitum and at 75, 55 and 30 g/kg0.75/day. We particularly expected digesta mean retention times (MRT) to increase, and hence fibre digestibility to increase, with decreasing DMI. Ponies maintained BM on the first, but lost BM and body condition on DMI55 and DMI30. MRTs were negatively correlated to DMI and ranged (for particles <2 mm) from 23/31 h (hay1/2) on the ad libitum to 38/48 h on DMI30. Digestibilities of DM, nutrients and fibre components decreased from DMI75 to DMI30; apparent digestibilities of organic matter and NDF (hay1/2) dropped from 47/43% and 42/37%, respectively, on the ad libitum DMI to 35/35% and 30/28% on DMI30. Additional differences evident between the two hays included a higher estimated ‘true’ protein digestibility for hay1 and finer faecal particles on hay2; there were no differences in faecal particle size between intake levels. The results suggest that below a certain food intake threshold, the major digestive constraint is not fermentation time but nutrient supply to gut bacteria. The threshold for such an effect probably varies between feeds and might differ between ruminants and equids.  相似文献   

4.
The objective of this study was to compare the feed intake, digestibility and metabolism in lambs fed low‐quality roughage with those of lambs fed normal roughage from an early stage of their life. The study consisted of two treatments [low‐quality roughage group (LR) and control group (C)] over three time periods (P1, P2 and P3; 2 months each). Four lambs (4 months old) were allocated to each treatment. In P1 and P2, LR was fed sudangrass hay (CP: 5.1% DM; NDF: 70.4% DM), whereas C was fed timothy hay (CP: 8.4% DM; NDF: 60.3% DM). In P3, all lambs were fed sudangrass hay. Although the feed intake was significantly greater (p < 0.05) in C in P1, there were no differences between the groups in P2. The digestibility, serum glucose (GLU), urea nitrogen (SUN) and insulin‐like growth factor 1 (IGF‐1) did not differ between the groups in P1 and P2. The average nitrogen retention, triiodothyronine (T3) and thyroxine (T4) were significantly higher in C (p < 0.05) during P1 and P2. No interaction was observed between the treatment and periods. In P3, the feed intake was greater in C (p < 0.05), whereas digestibility and nitrogen retention tended to be greater in LR. The body weight did not differ between the treatments. T4 and T3 were numerically lower in LR, while the SUN was greater in LR (p < 0.05). These results suggest that the early experience with low‐quality roughage may have improved feed digestibility and nitrogen metabolism in lambs after 4 months of rearing. Furthermore, the experienced lambs became more efficient at utilizing the low‐quality roughage. The lower thyroid hormone concentrations observed in LR suggest an adaptive change occurred in experienced lambs that to a lower basal metabolic rate.  相似文献   

5.
The effect of dietary dry matter intake (DMI) on endogenous nitrogen (N) flows at different part of the digestive tract of growing lambs was determined using a 15N isotope dilution technique. Three Kazakh male lambs (30 ± 2.75 kg of body weights and 4 months old, average daily gain 200 g/day) were fitted with ruminal, duodenal and ileal cannulae and raised in metabolic cage individually. The experiment was conducted in a 3 × 3 Latin square design with three lambs, three DMI levels (1100, 920 and 736 g/day respectively) and three periods. Each period lasted 18 days, consisting of 10 days for adaptation, 8 days for the continuous infusion of l ‐[15N]leucine, during which the intestinal flow of N and 15N enrichment were determined. The total endogenous secretions in the forestomach (Sfs) were decreased (p = 0.0512) with increased level of DMI. On the contrary, endogenous nitrogen (EN) secretions into the small intestine (Si) increased (p = 0.0249) significantly with the high level of DMI (HI) group compared with that of low level of DMI (LI). Total absorption from forestomach was reduced (p = 0.0121) with increased level of DMI, whereas total absorption from small intestine for HI group increased (p = 0.0116) significantly compared with that of LI treatment. The real digestibility of N in the rumen accompanied with the increase in feed intake is decreased (p = 0.081). In contrast, there were no effects of DMI level on the computed real digestibility of N across both small intestine and whole tract. The results of this study indicate that the total flows of EN at duodenum may be unaffected by the level of DMI; however, the EN flow at ileal level increased from 12% to 37% with the increase in DMI level, corresponding to 33% of total N flow at ileum.  相似文献   

6.
Calves following an enhanced-growth feeding program usually show lower starter intakes during the preweaning period compared with conventionally-fed calves. To assess whether this low intake in calves following an enhanced-growth feeding program affects calf capacity to digest starter after weaning, 19 Holstein male calves were used to measure apparent nutrient digestibility at weaning. Calves were divided in two groups: calves on a conventional feeding program (CF) and calves on an enhanced-growth feeding program (EF). After one week of adaptation to milk replacer (25% CP and 19% fat), the CF calves were fed 4 l/d of milk replacer (MR) at 12.5% DM dilution rate from d 1–28, and 2 l/d from d 29 to weaning day at d 35, and the EF calves were offered MR at 18% DM dilution rate: 4 l/d from d 1–6, 6 l/d from d 7–13, 7 l/d from d 14–20, 6 l/d from d 21–28, and 3 l/d from d 29 to 35. Calf starter (20% CP) was offered ad libitum from the beginning to the end of study at d 42, and its consumption was recorded daily. Calves were weighed at d 3, 17, 24, 31, 38 and 42. Daily total faeces collection was conducted for the last 5 d of study. Final BW was numerically greater in EF than in CF calves (88.6 vs 81.2 ± 3.36 kg, respectively). Starter DMI was greater (P < 0.05) in CF compared with EF calves during the preweaning (0.68 vs 0.36 ± 0.078 kg/d, respectively) and postweaning (2.52 vs 1.90 ± 0.102 kg/d, respectively) periods, but there were no differences in total DMI (1.12 and 1.26 ± 0.078 kg/d, in CF and EF calves, respectively) during the preweaning period. However, apparent DM, OM, NDF, CP, and GE digestibility coefficients were greater (P < 0.05) in CF compared with EF calves (77.4 vs 71.8 ± 1.23%, 78.7 vs 73.2 ± 1.18%, 34.7 vs 20.3 ± 3.79%, 77.1 vs 71.6 ± 1.29%, and 75.6 vs 69.8 ± 1.25%, respectively) the week after weaning. It is concluded that calves in the EF treatment presented lower nutrient digestibility coefficients compared with CF calves the week after weaning.  相似文献   

7.
The experiment was conducted at Dilla Agricultural Technical Vocational Education and Training (ATVET) College in Ethiopia using twenty-four yearling intact male Sidama goats with a mean body weight (BW) of 16.8 ± 1.14 kg (mean ± SD). The objective of the experiment was to examine the effect of different levels of cottonseed meal (CSM) supplementation on the feed intake, digestibility, BW gain, and carcass parameters of Sidama goats. The experiment consisted of 90 days of feeding trial and 10 days of digestibility trial followed by evaluation of carcass parameters at the end of the experiment. The treatments included ad libitum feeding of hay (T1, control) and daily supplementation of CSM at 200 g (T2), 300 g (T3) and 400 g (T4) per head on dry matter (DM) basis. The experimental design was a completely randomized block design. The experimental goats were blocked on initial BW and six goats were randomly assigned to each treatment. Hay DM, crude protein (CP) and neutral detergent fiber (NDF) intake were higher (P < 0.001) in the non-supplemented than in the supplemented goats, however, the contrary was true for total CP intake. Total DM intake was higher (P < 0.001) for goats supplemented with the high level of CSM than those on the control treatment. Among CSM supplemented goats, the intake of CSM DM, CP, NDF (P < 0.001) and total CP (P < 0.01) were higher in the order of T4 > T3 > T2. The high level of supplementation with CSM resulted in better (P < 0.05) apparent digestibility coefficient (DC) of DM and organic matter (OM) compared to the non-supplemented goats. The apparent DC of CP was higher (P < 0.01) for supplemented than non-supplemented goats. The non-supplemented goats had lower daily BW gain, empty BW, dressing percentage on slaughter weight base, rib-eye muscle area (P < 0.01), BW change (P < 0.001), final BW (P < 0.05) and higher feed conversion ratio (P < 0.01) than the supplemented ones. The medium level of supplementation resulted in higher daily BW gain (P < 0.01), BW change (P < 0.001), final BW (P < 0.05) and lower feed conversion ratio (P < 0.01) than the lower level of supplementation, but with no differences (P > 0.05) in these parameters with the high level of supplementation. Therefore, it is concluded that supplementation of CSM at 300 g DM per head per day resulted in better animal performance parameters in Sidama goats.  相似文献   

8.
The objective of this experiment was to study the effects of interactions between medium quality grass silage (GS1) and maize silage (MS) as well as between low-quality grass silage (GS2) and MS on ad libitum intake, digestibility and N retention in wether sheep. Two grass silages (GS1 and GS2) were ensiled in round bales, without additives, from the primary growth of orchard grass (Dactylis glomerata L.) harvested at two different maturity stages. The study consisted of seven feeding treatments incorporating GS1, GS2 and MS fed alone and forage mixtures of GS1 and MS as well as GS2 and MS (67:33% and 33:67%, respectively, DM (dry matter) basis).Delayed harvesting lowered (P < 0.05) the crude protein (CP) concentration in GS2 compared to GS1. The DM content (g kg− 1 fresh sample) and starch concentration (g kg− 1 DM) of MS were 264 and 211, respectively.Inclusion of MS in the GS1-based ration had positive linear effects on CP and starch digestibility (P < 0.05 and P < 0.01, respectively) and N intake (P < 0.01) while a negative effect on neutral detergent fibre (NDF) and acid detergent fibre (ADF) digestibility (P < 0.05 and P < 0.01, respectively). A positive associative response of GS1 and MS was observed for DM ad libitum intake (g kg− 1 M0.75 day− 1) (quadratic, P < 0.05), CP digestibility (quadratic, P < 0.01), N intake (quadratic, P < 0.01) and N balance (quadratic, P < 0.05). Inclusion of MS into the GS2-based ration had a positive linear effect on the ration fresh matter ad libitum intake (kg day− 1 and g kg− 1 M0.75 day− 1) (P < 0.01 and P < 0.001, respectively), NDF ad libitum intake (kg day− 1 and g kg− 1 M0.75 day− 1) (P < 0.01), digestibility of DM (P < 0.01), organic matter (OM) (P < 0.01), ADF (P < 0.05), starch (P < 0.001), digestibility of OM in DM (D-value) (P < 0.001), and N intake (P < 0.01). Positive associative effects of GS2 and MS were observed on all the intake and digestibility parameters measured, N intake (quadratic, P < 0.001) and N balance (quadratic, P < 0.05). It was concluded that, as expected, a positive associative response of GS2 and MS was recorded for all the measured parameters while that of GS1 and MS for a limited number of parameters, probably due to lower quality of MS (lower starch concentration) than required for improved utilization of the GS1-based ration.  相似文献   

9.
The objective of this study was to evaluate the effects of increasing garlic powder and monensin supplementation on feed intake, nutrient digestibility, growth performance and blood metabolites of growing calves. Forty Holstein calves (BW = 100 ± 11 kg) were randomly assigned to four dietary treatments (n = 10) in a complete randomized design. Experimental treatments consisted of the following: (i) basal diet (control), (ii) basal diet supplemented with 0.0003% of dietary dry matter (DM) sodium monensin, (iii) low level of garlic powder (Low‐GAR; 0.5% of dietary DM) and (iv) high level of garlic powder (High‐GAR; 1% of dietary DM). DM intake (DMI) and DM digestibility were (p < 0.05) decreased by High‐GAR. However, calves supplemented with Low‐GAR had a similar DMI to the control calves and similar DM digestibility to the control and monensin groups. The digestibility of other nutrients were not affected by the treatments. Although supplementing monensin relative to Low‐GAR increased the DMI (p < 0.05), average daily gain was similar between Low‐GAR and monensin supplemented calves, which were higher than the control and High‐GAR groups (p < 0.05). As a result, feed conversion ratio was improved in the Low‐GAR group versus other treatment groups (p < 0.05). Administrating garlic powder decreased the blood low‐density lipoprotein (LDL) and non‐esterified fatty acids (p < 0.05) without affecting the blood triglyceride, high‐density lipoprotein and beta‐hydroxybutyric acid concentrations. In conclusion, the calves fed the Low‐GAR showed an improved FCR and blood metabolites without changing the DMI and nutrient digestibility. It suggests that garlic powder could be used as an alternative to monensin for growing calves under the current feeding conditions.  相似文献   

10.
Energy intake prepartum is critically important to health, milk performance, and profitability of dairy cows. The objective of this study was to determine the effect of reduced energy density of close-up diets on dry matter intake (DMI), lactation performance and energy balance (EB) in multiparous Holstein cows which were housed in a free-stall barn and fed for ad libitum intake. Thirty-nine dry cows were blocked and assigned randomly to three groups fed a high energy density diet [HD, n = 13; 6.8 MJ of net energy for lactation (NEL)/kg; 14.0% crude protein (CP) ], or a middle energy density diet (MD, n = 13; 6.2 MJ NEL/kg; 14.0% CP), or a low energy density diet (LD, n = 13; 5.4 MJ NEL/kg; 14.0% CP) from d 21 before expected day of calving. After parturition, all cows were fed the same lactation diet to d 70 in milk (DIM). The DMI and NEL intake prepartum were decreased by the reduced energy density diets (P < 0.05). The LD group consumed 1.3 kg/d (DM) more diet compared with HD group in the last 24 h before calving. The milk yield and the postpartum DMI were increased by the reduced energy density diet prepartum (P < 0.05). The changes in BCS and BW prepartum and postpartum were not affected by prepartum diets. HD group had higher milk fat content and lower lactose content compared with LD group during the first 3 wk of lactation (P < 0.05). The energy consumption for HD, MD and LD groups were 149.8%, 126.2% and 101.1% of their calculated energy requirements prepartum (P < 0.05), and 72.7%, 73.1% and 75.2% during the first 4 wk postpartum, respectively. In conclusion, the low energy density prepartum diet was effective in controlling NEL intake prepartum, and was beneficial in increasing DMI and milk yield, and alleviating negative EB postpartum.  相似文献   

11.
A digestibility, feed intake, and carcass evaluation experiment using 20 yearling intact male Sidama goats weighing 16.4 ± 0.63 kg (mean ± SD) was conducted in Ethiopia with the objectives to determine feed intake, digestibility, body weight (BW) gain, and carcass parameters. The treatments included feeding natural pasture hay (T1, control) and supplementation with cottonseed cake (284 g—T2), linseed cake (250 g—T3), and noug seed cake (296 g—T4) on dry matter (DM) basis to supply 85 g crude protein (CP) per head per day. Randomized complete block design for feed intake and BW parameters and complete randomized design for digestibility and carcass parameters were used. Hay DM intake was higher (P < 0.01) for T1 than for the other treatments. T3 promoted higher (P < 0.01) DM (29.3 g/kg W0.75/day) and CP (14.1 g/kg W0.75/day) intake than T4 (8.9 g/kg W0.75/day DM and 4.1 g/kg W0.75/day CP). T3 showed better (P < 0.05) organic matter and CP digestibility than T2. Goats in T3 had higher nitrogen intake (P < 0.01) and retention (P < 0.05) than those in T1. Goats in T2 and T3 showed higher (P < 0.05) daily BW gain and final BW than those in T4 and T1. Goats in T2 and T3 had higher (P < 0.05) slaughter weight, empty BW, hot carcass weight, rib-eye muscle area, and dressing percentage on slaughter weight basis than those in T1. The results showed that T2 and T3 had similar effect on CP intake, daily BW gain, and carcass parameters for growing Sidama goats fed natural pasture hay.  相似文献   

12.
To examine whether type of maize silage is important for milk production performances, maize silage LG30224 (LG) was compared with Falkone (FA), the latter having a 4.0% points lower rumen NDF digestibility and 19 g/kg dry matter (DM) more starch. To bridge the lower energy content of FA, a third treatment was involved by adding maize meal (MM) in a ratio of 92/8 on DM (FA+MM). Maize and grass silage were fed ad libitum in a ratio of 65/35 on DM basis. Concentrates were supplemented individually to meet energy and protein requirements. The experiment was set up as a Latin square with three groups of nine Holstein cows during three periods of 3 weeks. In the last 2 weeks of each period, DM intake (DMI) and milk performances were measured. Each group included one cannulated cow to study effects on rumen fermentation. During the last 4 days of each period, two cows from each group were placed in gas exchange chambers to measure nutrient digestibility and methane production. Total DMI was higher (p < 0.05) for FA+MM (20.8 kg/day) than for FA (20.3 kg/day), while DMI for LG was intermediate (20.6 kg/day). Treatment did not affect milk production nor composition, whereas fat–protein‐corrected milk was higher for LG (30.5 kg/day) and FA+MM (30.3 kg/day) than for FA (29.9 kg/day). The ration did not affect pH nor volatile fatty acid composition in the rumen. Further, total tract digestibility of OM, crude protein, NDF and starch did not differ among treatments. The ration with LG gave higher methane production per day and per kg NDF intake than both rations with FA, but the difference was not significant when expressed per kg DMI or FPCM. Thus, maize silage type is of little importance for milk production if energy and physical structure requirements are met.  相似文献   

13.
This study was conducted to evaluate the effects of single or carbohydrases cocktail in low-nutrient-density diets on growth performance, nutrient digestibility, blood characteristics, and carcass traits of growing–finishing pigs. A total of 96 pigs with an average initial BW of 47.50 ± 1.25 kg were used in this 8-week growth trial. Pigs were randomly allocated to 1 of the 4 treatments according to its BW and sex (4 pigs/pen, 6 replicate pens/treatment). The diets included: 1) control (CON) corn–soybean meal diet (DE, 3400 kcal/kg; CP, 17%), 2) low-nutrient-density (LC) diet with 6% DDGS and 5% tapioca (DE, 3280 kcal/kg; CP, 15%), 3) LC + 0.05% β-mannanase (LCS), and 4) LC + 0.05% enzyme mixture (LCM). The LC treatment had a lower ADG, and G/F compared to the other treatments in 0–4 weeks and the overall period of the feeding trial (P < 0.05). The ADFI were decreased in LC, LCS, and LCM groups related to CON (P < 0.05). The LCS treatment had higher DM digestibility than pigs in both the LC and LCM groups (P < 0.05) on 4 weeks while LCM improved N and energy digestibility compared to LC treatment. Blood urea nitrogen and creatinine values were not affected by the experimental treatments. After the feeding period, pigs (2 per pen) which reached marketing BW were collected meat samples from slaughter house. Backfat thickness was decreased in LC, LCS and LCM groups (P < 0.05). No numerical differences were observed in meat color, pH value and water holding capacity among four treatments. In conclusion, the results of this study indicate that single or carbohydrases cocktail in low-density diets can partially improve ADG, G/F, nutrient digestibility, and meat quality in finishing pigs, which can counteract the negative effects caused by the decreased nutrient concentration.  相似文献   

14.
Feed palatability and in vivo apparent digestibility of nutrients were compared in horses fed concentrates in which barley was, or not, partially substituted by 8% linseed oil. According to a cross-over design, three geldings and one stallion were fed at near maintenance level hay plus low or high fat diet (50/50). The last days of each 3-months sub-periods, partial faeces collections were performed and concentrate intake rate was measured to estimate the digestibility and the palatability of the diet. The inclusion of linseed oil did not affect the palatability of the diet and increased significantly (P < 0.05) the apparent digestibility of DM (66.5 vs 64.1%), CF (83.7 vs 57.3%) and NDF (53.0 vs 50.7%) but not of CP and ADF.  相似文献   

15.

Eight male Cambodian yellow cattle, initial body weight (BW) 136 ± 11.9 (±SD) kg; age 20 ± 2.5 (±SD) months, were randomly allocated to treatments in a double 4 × 4 Latin square design to investigate the effects of different levels of crude protein (CP) from sun-dried groundnut (Arachis hypogaea L.) foliage (DGF) on feed intake, apparent digestibility and nitrogen metabolism. All animals were fed a basal diet of rice straw ad libitum and para grass (Brachiaria mutica) at 1% of BW. The DGF was offered as a supplement at 0, 1, 2 and 3 g CP/kg BW, denoted DGF0, DGF1, DGF2 and DGF3, respectively. The results showed that the intake of DGF contributed 0, 25, 34 and 42% of total dry matter (DM) intake. Rice straw intake decreased when DGF intake increased. Total intake of DM, organic matter (OM), digestible OM, ash, neutral detergent fibre and acid detergent fibre increased with increased level of DGF inclusion but did not differ for the two highest DGF levels. Total DM intake as proportion of BW increased from 2.3% in DGF0 to 2.8% in DGF3. Crude protein digestibility and nitrogen retention improved as DGF intake increased. Daily weight gain of DGF1 cattle was higher than DGF0 but was not further improved at the higher levels of DGF inclusion. Microbial protein synthesis and efficiency of microbial protein production in DGF1 did not differ from DGF0 but both measures were higher in DGF2 and DGF3. The responses were diminished at higher DGF inclusion so it is suggested that DGF supplementation at 1 g CP/kg BW may be the optimal level.

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16.
This study evaluated methane (CH4) emission, intake, digestibility, and nitrogen efficiency in sheep fed diets containing replacement levels (0%, 33%, 50%, and 67% of soybean meal with euglena). In this experiment, four Corriedale wether sheep with an initial body weight of 53.8 ± 4.6 were arranged in a 4 × 4 Latin square design. This experiment lasted 84 days, divided into four experimental periods. Each period lasted 21 days, which consists of 14 days of adaptation to the diets, 5 days to collect samples, and 2 days to collect gas emission from sheep. Methane emission expressed as L/kg DM intake or g/kg DM intake reduced by up to 37% and the energy loss via CH4 (% of GE intake) reduced by up to 34%. No differences (p > 0.05) were observed in DM and OM intake and whole tract apparent DM digestibility due to substitution of soybean meal with euglena. The total CP loss reduced significantly (linear, p < 0.001) and CP efficiency increased linearly (p = 0.03) with increasing concentration of euglena. As a result, nitrogen balance and average daily weight gain remained unchanged despite higher nitrogen concentration in soybean supplemented group. In conclusion, substitution of soybean meal with euglena reduced methane emission without affecting the performance of animals.  相似文献   

17.
The objective of the study was to observe the effect of protein density of concentrate mixture on the growth performance of Red Chittagong Cattle (RCC) heifers (Bos indicus), an endangered variety in Bangladesh. The experiment was conducted for a period of 90 days with 12 RCC heifers, and the animals were divided into four groups on the basis of their initial live weight. The animals were assigned at random to four dietary treatments having three replications in each in a randomized complete block design. Three iso-energetic [10.5 MJ metabolizable energy (ME)/kg dry matter (DM)] concentrate mixtures were formulated to provide protein concentrations (%) of 15, 20, and 25 for T1, T2, and T3, respectively. Crude protein (CP) content of control diet was 7.08%. Animals of all groups were fed urea molasses straw (UMS) ad libitum and green grass at a rate of 20% of total DM intake. Digestibility of DM was highest in the treatment group fed 25% CP supplement (T3) and lowest in the unsupplemented group (T0). Average daily gain increased with increasing CP concentration in supplements, but mean difference was not significant between the 20% and 25% CP groups. Feed cost per kilogram live weight gain was lowest (P > 0.05) in 20% CP supplement and highest in the unsupplemented group. The results revealed that the CP concentration of 20% in concentrate mixture containing 10.5 MJ ME is cost effective with the UMS-based diet of RCC heifers for better nutrient digestibility and growth.  相似文献   

18.
Supplementation of yeast culture to equine diets has improved digestion of nutrients in some studies but not others. Improving the digestibility of lower-quality forages could be advantageous both for the producer and for the horse's health. The objective of this study was to evaluate the effect of yeast culture on digestibility of high- and low-quality forage in mature horses. Sixteen geldings (483.6 ± 25.5 kg and 6.8 ± 3.2 years), of Quarter Horse (n = 14) and Thoroughbred (n = 2) breeding, were used in a 4 × 4 Latin square design with 28-day treatment periods. Russell Bermuda grass hay of either high (13.1% crude protein (CP), 73.1% neutral detergent fiber (NDF), 35.3% acid detergent fiber (ADF), and 6.0% ash) or low (8.1% CP, 75.3% NDF, 37.6% ADF, and 4.3% ash) quality was offered at 1.35% of body weight (BW, dry matter [DM] basis). Diets consisted of high-quality forage with the addition of yeast culture (HY), high-quality forage without yeast culture (HC), low-quality forage with the addition of yeast culture (LY), and low-quality forage without yeast culture (LC). All horses were fed a commercial grain mix (12.6% CP, 25.4% NDF, 12.1% ADF, and 4.0% ash) offered at 0.45% of BW (DM basis) daily. Yeast culture was added to the grain mix during the morning feeding at a rate of 56 g per horse. Body weight was measured weekly and feed intake was adjusted accordingly. Fecal samples were obtained every 6 hours on the last 3 days of each treatment period. Horses receiving low-quality hay (LY and LC) had greater (P < .01) intake expressed as a percentage of BW compared with horses receiving high-quality hay (HY and HC). No influence of yeast culture supplementation was seen on intake of grain or forage (P < .23 and P < .62, respectively). Digestibility of DM, organic matter (OM), CP, and NDF were greater (P < .01, P < .01, P < .01, and P < .01, respectively) for the diets with high-quality forage compared with the diets with low-quality forage. Dry matter, CP, and NDF digestibilities were greater (P < .09, P < .03, and P < .05, respectively) for horses receiving LY compared with LC. Supplementation of yeast culture to mature horses improved digestibility of lower-quality Bermuda grass hay.  相似文献   

19.
This study aimed to investigate the effect of dietary supplementation with Lactobacillus plantarum and Bacillus subtilis on growth performance, apparent nutrient digestibility and stress‐related indicators in dairy calves. Twenty‐four neonatal Holstein calves were randomly allocated to three treatments: a basal diet with no supplementation (control), the basal diet supplemented with 1.7 × 1010 CFU per head per day (CFU/h.d) of L. plantarum GF103 (LB group) or the basal diet supplemented with a mixture of L. plantarum GF103 (1.7 × 1010 CFU/h.d) and B. subtilis B27 (1.7 × 108 CFU/h.d) (LBS group). Dry matter intake (DMI), average daily gain (ADG), feed conversation ratio (FCR), apparent digestibility of nutrients and stress‐related indicators were measured in this trail. The result indicated that no significant differences were observed in DMI or ADG (p > 0.05), but the FCR was improved in the LB group over the first 12 weeks (p > 0.05). The apparent digestibility of nutrients was not altered by probiotics in week 6 (p > 0.05), but the apparent digestibility of total phosphorus was significantly greater in the LB and LBS groups in week 8 (p > 0.05); additionally, an increase in the apparent digestibility of crude protein was detected in the LBS group (p > 0.05). Oral administration of L. plantarum alone improved the T‐lymphocyte transformation rate on days 58 and 62 (p > 0.05), while adding the mixture of L. plantarum and B. subtilis increased the T‐lymphocyte transformation rate (p > 0.05) but decreased the content of cortisol on day 58 (p > 0.05). No significant differences were detected between the LB and LBS groups in growth performance, apparent digestibility of nutrients and stress‐related indicators (p > 0.05). The results suggested that oral administration of L. plantarum improved growth performance, nutrient digestibility and relieved weaning stress in calves, but no additional effect was obtained by supplementation with B. subtilis.  相似文献   

20.
The study aimed to evaluate the effect of feeding Borrena hirticulata (BH), Ficus hirta (FH), rice straw (RS) and concentrate-based total mixed ration (TMR) on nutrient utilization, rumen fermentation and growth in mithun. Growing male mithun calves were randomly allotted to 2 feeding groups (6 in each), TMR1 and TMR2. The TMRs consisted of RS 300 g kg− 1, concentrate 400 g kg− 1 and BH 300 g kg− 1 (TMR1) or FH 300 g kg− 1 (TMR2) on a dry matter (DM) basis. Both TMRs were fed ad libitum to the animals for 121 d and a digestibility study was conducted during the last 7 d of the experiment. To assess rumen fermentation, rumen fluid was collected at 2 h interval for 24 h. Apparent digestibility of DM, crude protein (CP) and crude fibre (CF) did not differ significantly between the TMRs. Nevertheless, apparent digestibility of ether extract was found to be significantly (P < 0.01) greater in TMR2 (0.59) compared to TMR1 (0.54). Body weight gain (BWG; g d− 1), DM intake (kg d− 1), CP intake (g d− 1) and feed efficiency (kg feed kg− 1 gain) were found to be significantly (P < 0.05) greater in TMR1 (548, 5.14, 713 and 9.28) compared to TMR2 (496, 4.91, 703 and 10.03). An insignificant positive association (r = 0.35) between DM intake and BWG, but a significant (P < 0.01) positive association (r = 0.74) between CP intake and BWG were evident. Rumen pH (5.71 to 7.18) and ammonia-nitrogen (8.0 to 25.0 mg/dl) did not differ significantly between the TMRs, but differed significantly (P < 0.01) at different h post-feeding. In contrast, rumen total volatile fatty acid (42 to 105 mM) and total nitrogen (40.4 to 90.3 mg/dl) differed significantly (P < 0.05) between the TMRs and at different h post-feeding. The study revealed that BH, FH, RS and concentrate-based TMRs may be fed to mithun for satisfactory growth.  相似文献   

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