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1.
The experiment studied the effects of long-term cold climatic housing conditions at a latitude of 62°N on pregnant Hereford cows and their progeny. Thirty-five cows in their third parity were overwintered in outdoor facilities with either a rain-shelter or a three-wall shelter, or in an uninsulated barn. Whole-crop barley silage was offered to the cows either ad libitum or restricted supplemented with oats. The dry matter intake on the restricted diet was 75% of that on the ad libitum diet. The cow live weight (LW) averaged 670 kg at the onset of the experiment. During winter the cows outdoors on the restricted diet maintained their LW while those on the ad libitum diet gained LW (P < 0.05, − 3 vs. 41 kg). On pasture, the LW gain (LWG) was 61 and 32 kg (P < 0.05) for the cows overwintered outdoors on the restricted and on the ad libitum diets, respectively. The initial body condition score (BCS, Scale: 0–5) of the cows averaged 2.90. During winter the cows outdoors on the restricted diet decreased and those on the ad libitum diet increased the BCS (P < 0.01, − 0.14 vs. 0.21). On pasture, the cows overwintered outdoors on the restricted diet increased the BCS more than those overwintered on the ad libitum diet (P < 0.05, 0.31 vs. 0.08). No signs of extraordinary stress, massive consumption of energy stores, frequent muscle injuries or severe inflammations occurred in any of the groups according to blood analyses of cows, e.g. cortisol, long-chain fatty acids, aspartate aminotransferase, creatine kinase and white blood cell count. The calving period was from 11 March to 21 April. Only one indoor calving was classified as difficult due to faulty disposition leading to the loss of the calf. All outdoor calvings were easy. The LWG of the indoor calves of cows on the ad libitum diet was poorer (P < 0.05) pre the grazing period than that of the outdoor calves of cows on the ad libitum diet. On pasture and during the entire experiment the LWG was similar for all calves, averaging 1335 and 1251 g/d, respectively. The breeding season was 82 days. Thirty cows out of 33 were observed to be pregnant after the mating period. All the facilities offered adequate shelter for the mature, pregnant suckler cows. The restricted offering of whole-crop barley silage provided, on average, 101 MJ metabolizable energy/d and gave enough energy for the cows.  相似文献   

2.
Eighteen Iberian barrows of 100 kg initial BW were used in a comparative slaughter experiment to investigate the effects of feeding level (FL; 0.70 and 0.95 × ad libitum) on growth, protein- and fat-deposition rates and body composition. They were fed on a diet supplying the optimum level of digestible ideal protein:ME ratio (4.82 g/MJ) and slaughtered at 150 kg BW. The apparent digestibility of DM, OM, total N and GE, and the ME:GE and ME:DE ratios were not affected by FL. The average daily gain increased with the increase in FL (691 and 918 g/day respectively). Neither the gain:feed (g/g DM) nor the gain:ME intake (g/MJ) ratios were significantly affected however. An energy cost of 59.9 kJ ME/g gain was calculated. The rate of whole-body protein deposition was not significantly altered by FL. On average it reached 80 g/day. The pigs fed at the lowest level exhibited lower fat deposition (P < 0.01) and total energy retention (P < 0.01) than those in the group subjected to only a slight feed restriction. The overall efficiency of utilization of ME for energy gain (ER:ME intake) remained at 0.363 on average, irrespective of the FL imposed. Relative proportions of energy retained as protein and fat were not statistically altered by changes in FL. Mean values for ERP:ER and ERF:ER were 0.100 and 0.903 respectively. No differences between treatments were observed in fat, ash, water or energy content of the whole-body (g/kg) at 150 kg empty BW, the mean values (n = 12) being 512 ± 8.5, 27.6 ± 0.63 and 353 ± 6.7 g/kg for fat, ash and water respectively and 22.90 ± 0.31 MJ/kg for energy. Nevertheless, the proportion of protein tended to decline with the increase in FL (111 vs 104; P = 0.069). At 150 kg the Iberian pigs contained more fat and energy and less ash and water than at 100 kg. Whilst the percentage of lean tissue decreased significantly (P < 0.05) and protein content in the carcass showed a strong tendency to decline in the pigs fed close to ad libitum (104 vs 96; P = 0.056), the proportions of fat, ash, water and energy remained constant at 564 ± 9.0, 22.2 ± 0.91, 312 ± 6.6 g/kg, and 24.82 ± 0.32 MJ/kg, respectively. It was concluded that a degree of feed restriction may result in a discernible improvement in carcass quality.  相似文献   

3.
The objective of this study was to compare the effects of ad libitum and restricted computer-controlled milk replacer (MR) feeding strategies on performance of group-reared dairy calves during preweaning (from 0.5 to 2.0 months of age), weaning (2.0 to 2.5) and postweaning (2.5 to 6.0) periods. Two feeding trials comprised a total of 34 Finnish Ayrshire and 6 Holstein–Friesian bull calves. The calves were randomly (balanced for breed) allotted to pens (5 calves/pen) which were thereafter randomly allotted to two experimental treatments: 1) ad libitum MR feeding (F) with ad libitum access to MR and 2) restricted MR feeding (R) where the calves were given 6.0 L of MR daily. All the calves had free access to water, commercial starter and grass silage before weaning. The weaned calves had free access to water and silage and were given 3 kg/day (air-dry basis) of a concentrate mixture. Due to increased metabolizable energy intake (16.4 vs. 12.7 MJ/day; P < 0.05), the daily gain of the F calves was higher (690 vs. 543 g/day; P < 0.05) than that of the R calves during the preweaning period. Due to the more rapid increase in concentrate intake of the R calves during the weaning period the R calves grew better than the F calves (482 vs. 1038 g/day; P < 0.01) and the differences in live weight evened out during the weaning period. During the postweaning period there were no treatment differences in feed intake or gain. The average gain during the whole study was not affected by either of the treatments. Ad libitum feeding increased the variation in the MR intake and gain compared to restricted feeding.  相似文献   

4.
A total of 356 early lactation multiparous Holstein cows were used in a randomized complete block design to determine the effects of feeding extruded linseed on milk production and composition, and reproductive performance. Forty of these cows were randomly selected to study the effects of extruded linseed on milk fatty acid (FA) profile, individual feed intake and prostaglandin secretion. Cows were fed a 40:60 forage to concentrate ratio diet (17.9% CP, 27.7% NDF and 6.0% EE) ad libitum that was similar in composition between treatments except for the protein supplements that differed and were control (CTR: 4.9% extruded soybean) and linseed (LIN: 5.5% extruded linseed). Individual DM intake measured at 40 (23.0 kg/d) and 90 (24.2 kg/d) days in milk, and milk yield (45.0 kg/d) were not affected by treatment, but the lower (P < 0.05) milk fat percentage in cows fed LIN (2.65%) compared with CTR (2.86%) resulted in lower (P < 0.05) 4.0% fat-corrected milk yield for cows fed LIN (35.4 kg/d) compared with CTR (37.7 kg/d). Milk protein content was higher (P < 0.05) in LIN (3.04%) than in CTR (3.00%). The concentration of saturated FA was lower (P < 0.05) in milk fat from LIN (56.2%) compared with CTR (60.2%). Monounsaturated FA (35.7 vs. 32.7%) and polyunsaturated FA (8.0 vs. 6.9%) were higher in LIN (P < 0.05) than in CTR. Supplementation with LIN also increased (P < 0.05) the proportion of vaccenic acid (2.21 vs. 1.55%), total conjugated linoleic acid (0.91 vs. 0.72%) and n-3 FA (1.21 vs. 0.54%) in milk compared with CTR. Plasma concentrations of prostaglandin metabolite were numerically lower in LIN (106 pg/ml) compared with CTR (120 pg/ml) (P = 0.16) but reproductive performance was similar between treatments. In summary, extruded linseed reduced milk fat percentage and 4.0% fat-corrected milk yield and increased milk protein percentage and the content of healthy FA in milk without modifying DM intake, milk yield and reproductive performance.  相似文献   

5.
The objective of this study is to characterize the influence of immune stress induced by lipopolysaccharide (LPS) on protein utilization and turnover for early-weaned pigs. A total of 15, crossbred weanling pigs (initial body weight 10.15 ± 0.39 kg) were assigned to one of three treatments. Pigs were injected with LPS and fed ad libitum (LPS-challenge), or injected with endotoxin-free physiological salt solution (PSS) and fed ad libitum (control), or injected with PSS and fed the same amount of feed as LPS-challenged pigs (pair-feed). All pigs received a 4-d nitrogen balance trial. On d 1 and 3 of the trial, LPS-challenged pigs were injected intramuscularly with 200 μg/kg BW of LPS dissolved in 1 ml PSS. Pigs in other treatments were injected with 1 ml PSS. 15N-Glycine (5 mg/kg BW) was gastrically infused after the second injection. Feces and urine were collected daily to determine the N output throughout the duration of the trial. Lymphocyte blastogenesis (LB) and serum immunoglobulins (IgA, IgG, IgM) were also detected to illustrate the LPS-induced immune responses. Results indicated that the injection of LPS significantly (P < 0.01) elevated the LB and resulted in lower average daily gain (ADG), feed intake (ADFI) and efficiency of feed utilization than control pigs. Pair-fed pigs had higher performance than LPS-challenged pig but poorer than control pigs. Injection of LPS also resulted in significantly (P < 0.01) lower nitrogen intake and efficiency of utilization than controls, and more fecal N excretion than Pair-fed pigs (3.19 ± 0.85 vs. 2.19 ± 0.67 g/d, P < 0.05). The whole-body nitrogen flux (4.34 ± 0.19 vs. 11.35 ± 0.12 g N/kg BW0.75/d) and N accretion (5.57 ± 0.59 vs. 10.17 ± 1.12 g Pr/kg BW0.75/d) were acutely (P < 0.01) reduced as the feed intake decreased, but there was no significant difference between LPS-challenged and pair-fed pigs. Injection of LPS markedly (P < 0.05) increased the protein degradation (16.76 ± 1.09 vs. 14.53 ± 1.24 g N/kg BW0.75/d). It is concluded that LPS-induced immune challenge depresses growth performance and feed utilization efficiency by enhancing protein degradation rate and decreasing protein utilization for body protein retention.  相似文献   

6.
The effect of toasted supplement on milk production was examined in three experiments on an organic study farm during the winter 2004/2005. Three types of iso-energetic supplement feed, toasted or untreated, were examined in each experiment, with an untreated cereal mixture as control. The supplement under investigation was: lupins in experiment 1, barley in experiment 2 and soybeans in experiment 3. The same forage mixture of grass-clover silage (84% of DM), grass pellets (11% of DM) and straw (5% of DM) was fed ad libitum in all the experiments.

Toasting decreased effective rumen protein degradability determined in situ for all three supplements. Compared to untreated lupins toasting of lupins tended (P = 0.10) to increase milk yield, whereas toasting of soybeans did not affect milk yield. Toasting of lupins decreased (P = 0.03) milk protein content (32.2 versus 32.7 g/kg), whereas toasting of soybeans did not affect milk protein content. ECM yield was significantly higher (P = 0.002) for cows fed toasted soybeans than for cows fed untreated soybeans (28.1 versus 26.4 kg ECM) whereas there was no significant effect on ECM yield from toasting lupins or barley. It can be concluded that the potential of toasting to increase the supply of metabolisable protein under organic feeding conditions is variable between feeds.  相似文献   


7.
I. Rokomatu  E.M. Aregheore   《Livestock Science》2006,100(2-3):132-141
Eighteen growing Fiji Fantastic (FF) sheep (nine ram lambs and nine ewe lambs), 5–6 months old, pre-experimental average body weight of 25.6 ± 0.82 kg were randomly divided into three groups of six and allotted to the treatments designated as A: Guinea grass (Panicum maximum); B: Guinea grass + concentrate mixture; and C: Guinea grass + crushed wheat grain in a completely randomized design experiment that lasted for 92 days. Total DM intake of sheep on forage + concentrate mixture were significantly higher (P < 0.001) than those on forage + crushed wheat grain and forage alone. Average daily gains (ADG) were 30, 75 and 42 g/day for forage, forage + concentrate mixture and forage + crushed wheat grain, respectively. ADG was significantly (P < 0.001) higher in sheep on forage + concentrate mixture. Daily protein intakes and BUN concentration were 3.59, 10.39 and 5.60 g/kg0.75/day; and 6.0, 9.7 and 6.0 mmol/l for sheep on forage alone, forage + concentrate mixture and forage + crushed wheat grain, respectively. BUN and glucose concentrations at the post-experimental period were significantly (P < 0.001) higher in sheep on forage + concentrate mixture. DM, organic matter (OM), crude protein (CP), acid detergent lignin (ADL), hemicellulose and energy digestibility were significantly (P < 0.001) higher in sheep on the concentrate mixture while neutral detergent fibre (NDF) digestibility was significantly (P < 0.001) higher in sheep fed crushed wheat grain. Sheep on the concentrate mixture were also significantly (P < 0.002) higher in metabolizable energy intake (MEI). Sheep on concentrate mixture had higher organic matter (OM) and crude protein (CP) digestibility, high DMI and ADG. In conclusion this experiment has provided some relevant lacking information on the average DMI and ADG of the FF sheep and a concentrate mixture of 16.5% CP plus 19.0 MJ GE/kg BW seems ideal to meet the protein and energy requirements of the FF sheep for growth in the tropical environment of Fiji. Finally data obtained also demonstrated the influence of supplementary concentrate feeding on DMI and ADG of the FF sheep.  相似文献   

8.
The aim of this study was to investigate the effects of increasing amounts of cereal-based concentrate on milk production. The study consisted of a series of three separate experiments in which cows were grazed in intensive rotation on timothy-meadow fescue pasture. In Experiment 1, 28 multiparous Holstein–Friesian cows received 0, 3, 6 and 9 kg concentrate in a cross-over designed trial with a fixed daily herbage allowance of 21 kg DM/cow. The energy-corrected milk yield increased linearly 0.84 kg/kg DM (P < 0.001), up to the 9 kg concentrate level. The milk fat (P < 0.001) and urea (P < 0.001) content decreased linearly (0.41 g/kg DM and 0.15 mmol/kg DM, respectively). The milk protein content tended (P = 0.08) to increase 0.10 g/kg DM with increasing supplementation.

In Experiment 2, 17 primiparous cows and 28 multiparous cows were used in a randomized-block designed trial with 3, 6 and 9 kg concentrate supplementation and a fixed 25 kg DM herbage allowance. The energy corrected milk yield increased linearly (P < 0.01) 0.67 kg/kg DM, whereas the milk urea content decreased linearly (P < 0.001) 0.27 mmol/kg DM. The milk protein content increased and the fat content decreased, but these differences were not significant.

In Experiment 3, a cross-over design was used to assess the response to concentrate supplementation of 24 multiparous cows (treatments: 6, 9 and 12 kg; fixed herbage allowance 25 kg DM) and 12 primiparous cows (treatments: 4, 7 and 10 kg; herbage allowance > 25 kg DM). The energy-corrected milk yield of the multiparous cows varied quadratically (Pquad < 0.001; 30.0, 32.5 and 32.2 kg for 6, 9 and 12 kg supplementation, respectively). Supplementation linearly decreased the urea (P < 0.001) 0.13 mmol/kg DM and fat (P < 0.001) 0.46 g/kg DM contents. The milk fat content also varied quadratically, showing the lowest content with the 12 kg level (Pquad < 0.05; 37.3, 37.3 and 34.9 g/kg for 6, 9 and 12 kg supplementation, respectively). The energy-corrected milk yield of the primiparous cows increased linearly (P < 0.001) 0.54 kg/kg DM up to 10 kg supplementation, whereas the milk urea (P < 0.001) and fat contents decreased linearly (P < 0.01) by 0.19 mmol/kg DM and 0.61 g/kg DM, respectively.

The results showed that the milk response remained linear up to the 9 kg supplementation level, but the highest level of supplementation resulted in only a marginal increase in milk yield. There was no interaction between season and milk or milk protein yield, which indicates that it is possible to maintain stable grazing conditions during the main grazing season in Nordic latitudes. The results support to some extent the hypothesis that the marginal milk response to supplementation increases with increasing milk production.  相似文献   


9.
A 2 × 2 factorial experiment was used to investigate the interaction between dietary crude protein (CP) concentration (200 vs 140 g/kg) and inulin supplementation (0 vs 12.5 g/kg) on nitrogen (N) excretion and intestinal microflora from 16 boars (n = 4, 74.0 kg live weight). The diets were formulated to contain similar concentrations of digestible energy and lysine. Pigs offered the high CP diets had a higher excretion of urinary N (P < 0.01), faecal N (P < 0.01) and total N (P < 0.001) than the pigs offered the low CP diets. Inulin supplementation increased faecal N excretion (P < 0.05) and decreased urine: faeces N ratio (P < 0.05) compared to the inulin free diets. There was no significant effect (P > 0.05) of dietary treatment on N retention. There was an interaction (P < 0.05) between dietary CP concentration and inulin supplementation on caecal E.coli. Pigs offered the diet containing 200 g/kg CP plus inulin decreased the population of E.coli compared to the inulin supplemented 140 g/kg protein diet. However, CP concentration had no significant effect on the population of E.coli in the unsupplemented diets. Inulin supplementation increased caecal bifidobacteria (P < 0.01) compared to the inulin free diets. In conclusion, inulin supplementation favourably altered N excretion and lowered the population of E.coli at high CP concentrations.  相似文献   

10.
A study was undertaken to evaluate the effects of incorporating high (HMS) and low (LMS) maturity maize silages into diets based on low (LGS) and high (HGS) feed value grass silages offered to beef cattle. Seventy-two continental cross-bred steers were used in a 14-week continuous design, randomised block experiment. The six treatments were arranged as a 2 × 3 factorial design incorporating the LGS and HGS offered as the sole forage, along with each of the two grass silages offered in a 60:40 ratio (DM basis) with the HMS and LMS. All diets were supplemented with 3 kg/head/day concentrates. Total daily DM and metabolisable energy intakes were higher (P < 0.001) for diets based on HGS compared to those based on LGS. Intakes were similar (P > 0.05) between diets containing LMS and HMS, both of which were higher (P < 0.001) than diets containing grass silage as the sole forage. Highest DM intakes were recorded with a mixture of HGS and HMS (P < 0.05 or greater). Cattle offered diets containing HGS had higher live-weight gain (P < 0.05), final live weight, carcass gain and carcass weight (P < 0.001) than those offered diets containing LGS. Feed conversion efficiency, assessed on a carcass gain basis, was poorer (P < 0.05) with diets containing LGS compared with those containing HGS, though differences between diets containing either LMS or HMS and GS as the sole forage were not significant (P > 0.05).  相似文献   

11.
This study investigated the effect of replacing concentrates with dry wormwood (Artemisia montana) on the performance of sheep. Four Corriedale × Polwarth sheep (41.3 ± 1.3 kg) were fed diets with an 8 : 2 straw to supplement ratio, for four, consecutive 16 d periods (10 d adaptation, 6 d collection) in a 4 × 4 Latin square design. Supplements were made by substituting 0 (Control), 30 (LW), 50 (MW) or 100 (HW) g/kg DM of concentrate (15.6% CP, 72.1% of TDN) with dried, ground wormwood. Ruminal pH, NH3–N and volatile fatty acids (VFA) were measured on d 6 of collection. Ether extract (EE) intake was linearly decreased (P < 0.001) with increasing wormwood inclusion, otherwise intake was unaffected. The Control diet had lower (P < 0.05) DM and CP digestibility than LW and MW diets and lower EE digestibility than the LW diet. Retained N (P < 0.05) and microbial N yield (P < 0.01) linearly increased with dietary wormwood level, but efficiency of microbial N synthesis linearly decreased (P < 0.001). Mean concentrations of rumen NH3–N, total VFA and propionic acid were quadratically increased (P < 0.05) by increasing wormwood inclusion. Replacing concentrates with 30–50 g/kg DM of wormwood increased N retention, microbial N yield and EE digestibility.  相似文献   

12.
The objective of this study is to investigate the effect of contrasting spring grazing dates (GD) and stocking rate (SR) on sward characteristics, grass dry matter intake and milk production performance of autumn calving dairy cows during the spring period. Two swards were created by grazing in March (early grazing; E) or by delaying first grazing until mid-April (late grazing; L). Two stocking rates, high (H; 5.5) and medium (M; 4.5) were applied across each sward. Forty eight autumn calving Holstein cows (160 ± 35 days in milk) were assigned to one of four (n = 12) different grazing treatments. The experiment began on April 17th and finished after 2 grazing rotations on June 20th. Later spring grazing significantly increased herbage mass (kg DM/ha) above ground level (+ 933, P < 0.05) and > 50 mm (+ 738, P < 0.05). Compressed sward height (+ 22.1 mm, P < 0.05), extended tiller height (+ 73 mm, P < 0.001) and pseudostem height (+ 35 mm, P < 0.001) were also significantly higher for later grazed swards. In the grazing horizon (> 80 mm— extended tiller height), later grazed swards had significantly lower leaf proportion (− 0.09, P < 0.05) and higher dead material (+ 0.05, P < 0.001). Daily herbage allowance (> 50 mm) was on average 12.7, 15.9, 18.2 and 21.9 kg DM/cow for EH, EM, LH and LM, respectively. Daily leaf allowance (> 80 mm) was 10.1, 12.3, 13.3 and 14.5 kg DM/cow for EH, EM, LH and LM, respectively. The EM (16.2 kg DM/cow), LH (+ 0.1 kg) and LM (0.8 kg) treatments all had similar grass DM intake, however there was evidence of an interaction (P < 0.10) between GD and SR, this was due to the low grass DM intake of the EH (13.9 kg DM/cow) treatment. When expressed as UFL (Fill unit) intake the EM treatment recorded the highest value. There was a significant interaction between GD and SR (P < 0.01) for milk, protein yield, 4% fat corrected milk yield (P < 0.05) and protein concentration (P < 0.001). Cows grazing the EM treatment produced 23.9 kg of milk, 876 and 685 g of fat and protein yield. The difference in milk production (cow/day) between EM and EH treatments was + 3.6 kg milk, + 98 g fat and + 107 g protein. The production yield difference between LM and LH treatments was + 1.1 kg milk, + 27 g fat and + 29 g protein in favour of the LM treatment (23.9 kg of milk, 877 and 687 g fat and protein yield). Herbage quality and morphological characteristics are clearly improved with early spring grazing as herbage mass is reduced on subsequent rotations. Swards grazed in early spring allow higher grass utilisation and high milk production performance when grazed at a medium stocking rate. Improved milk production from herbage can be achieved provided herbage mass and allowance are maintained at levels where herbage quality decreases are minimised.  相似文献   

13.
The objective was to study the relationships between the actual European beef carcass classification scale, which classifies carcasses with regard to conformation and degree of fat cover scores, and muscle fat quality, depending on breed and mh-genotype. For this purpose samples from 100 yearling bulls from “Asturiana de los Valles” (24 AV(mh/mh), 26 AV(mh/+), 25 AV (+/+)) and “Asturiana de la Montaña” (25 AM) were analysed. The results of the study showed that breed or genotype affect carcass measurement scores and muscle fatty acid profile through its important effect on animal overall fatness. Homozygous double-muscled animals produced carcasses with high conformation and low intramuscular (IM) fat content. While early-maturing and rustic AM animals produced low carcass yield and high IM fat content. The other genotypes (mh/+, +/+) showed, in general, intermediate characteristics. Referring to correlations, carcass conformation was negatively related to saturated (SFA) (r = − 0.69, P < 0.001) and monounsaturated fatty acid (MUFA) (r = − 0.69, P < 0.001) groups, and positively to polyunsaturated (PUFA) (r = 0.72), n-6 (r = 0.72), n-3 (r = 0.71) and unsaturated fatty acid (UFA) (r = 0.69) groups, being all of them significant (P < 0.001). However, carcass degree of fat cover was positively related to SFA (r = 0.53, P < 0.001) and MUFA (r = 0.62, P < 0.001), and negatively to PUFA (r = − 0.61), n-6 (r = − 0.60), n-3 (r = − 0.62) and UFA (r = − 0.53) groups, being all of them significant. Moreover, simple and low-cost prediction equations were calculated for a rapid and sufficiently accurate fatty acid group (SFA, MUFA, PUFA, n-6, n-3, UFA) estimation (R2 > 0.46, P < 0.001). In general, meat obtained from double-muscled animals display a more appropriate IM fatty acid profile from the nutritional point of view according to actual recommendations, but it could happen the disability of these lean animals to deposit sufficient IM fat to ensure consumer overall liking or acceptability.  相似文献   

14.
Phosphorus (P) from plant-derived feedstuffs is mainly in the form of phytic-P, which has a very low bioavailability in monogastric animals. The non-absorbed phytic-P may contribute to P pollution, reduce mineral bioavailability and might reduce protein digestibility. The aim of this study was to evaluate the effects of the recommended levels of Ronozyme® P CT 5000 (750 U/kg — RP) and Natuphos® 5000 (500 U/kg — Nat) on the ileal apparent digestibility of total P, phytates (Phy), calcium (Ca), total nitrogen (N), energy, and amino acids (AA) in 60-day-old ileo-rectal anastomosed pigs. In a double Latin square design they were fed ad libitum either a maize–rapeseed meal based diet or this diet supplemented with RP or with Nat. RP and Nat increased the digestibility of P by 148% and 162%, of Phy by 84% and 76%, and of Ca by 44% and 50%, respectively. The total N digestibility was increased by 4% with RP (P < 0.01) and by 1% with Nat. A numerically increase of the digestibility of most of the AA was observed for Nat and of all AA for RP. Threonine digestibility was significantly increased by RP (P < 0.05). The results of this study indicate that phytases are able to increase the availability of proteins.  相似文献   

15.
A feeding trial was carried out for 90 days to asses the supplementing effect of tagasaste forage as a substitute for a concentrate supplement (wheat bran–noug seed cake (Gizotia abyssinica) mixture in 3:1 proportion) using 24 Menz male sheep (initial weight of 18.3 ± 1.6 kg). The sheep were fed on natural pasture hay as basal diet. The treatments were iso-nitrogenous supplements of 100% concentrate offered at 200 g DM/sheep/day (T1), 67% concentrate + 33% tagasaste (T2), 33% concentrate + 67% tagasaste (T3) and 100% tagasaste (T4). Digestibility tests of treatment diets were done for 10 days following the feeding trial using the same experimental animals. At the end of the experiment, carcass parameters were also evaluated. In situ degradability of feeds was determined using three rumen fistulated crossbred steers. Tagasaste forage contains more CP (215 g/kg), ADF (221 g/kg), ADL (69 g/kg); and less NDF (351 g/kg) compared to the concentrate. The concentrate had a high immediately soluble fraction (a), and a low insoluble but potential degradable matter (b), while tagasaste had a low a and higher b values and the overall potential degradability was 755, 702, and 586 g/kg, for tagasaste, concentrate and natural pasture hay respectively. Tagasaste forage had also shown higher rates of degradation (c) compared to the concentrate which might increase the total effective degradability. In the feeding trial the supplements made 26.8, 27.0, 28.3 and 29% of the total dry matter (DM) intake for T1, T2, T3, and T4, respectively. Increasing the inclusion of tagasaste forage significantly (P < 0.01) decreased the daily total DM intake of the basal diet and total metabolizable energy (ME), and increased the CP intake. The average weight gain of sheep did not show significant difference (P > 0.05), but had a decreasing trend, with 44.4, 41.4, 38.9 and 38.1 g/sheep for T1, T2, T3, and T4, respectively. The in vivo digestibility of DM and nutrients generally followed the order of T1 > T2 > T3 > T4. The dressing percentage of the carcass was 40.4% and all other parameters measured did not show significant variation due to treatment diets (P > 0.05). However, weight of liver, kidney and spleen was higher for sheep fed with higher tagasaste forage diet. The result of this study revealed that tagasaste can substitute wheat bran–noug seed cake concentrate mixture as a protein supplement. Options to increase the low ME and minimize the effect of the anti nutritional factors will improve nutrient digestibility in tagasaste forage and will enhance the overall efficiency of feed utilization.  相似文献   

16.
Feeding whole barley and a protein supplement at choice to early weaned lambs (15 kg initial weight) was studied in four experiments. In a first experiment whole barley and a pelleted soybean meal-based supplement (348 g crude protein (CP)/kg dry matter (DM)) were given either at choice (CH) or mixed in a 75 / 25 ratio (M) and compared to a pelleted compound feed containing the same ingredients and supplemented with barley straw (C). The effect of allowing free access to straw in the CH treatment (CHS) was tested in a second experiment. Rumen fermentation was also studied in six lambs per treatment slaughtered after the growing period, and digestibility and allantoin excretion were determined in other four lambs per treatment. In Experiments 3 and 4 supplements containing 253–264 (L), 341–329 (M) and 424–427 (H) g CP/kg DM were offered at choice with whole barley to lambs penned individually (Experiment 3) or in a group (Experiment 4) and diet selection and lamb performance were recorded.

The protein supplement was selected in proportions of 0.28 and 0.34 (S.E. 0.021) of concentrate intake with treatments M and CH (Experiment 1) and 0.45 and 0.52 (S.E. 0.033) with treatments CH and CHS (Experiment 2). The concentration of rumen ammonia increased (P < 0.05) to 28 and 56 (S.E. 8.6) mg/l compared to 12 mg/l in treatment C. Rumen pH also increased (P < 0.001) from 4.95 to 5.48 and 5.60 (S.E. 0.080) with treatments CH and CHS while the concentration of volatile fatty acids and the acetate to propionate ratio tended to decrease (P < 0.1). Organic matter digestibility and allantoin excretion were higher with whole barley feeding (0.82 vs. 0.75 (S.E. 0.18) and 13.1 vs. 7.7 (S.E. 1.06) mmol/d) but decreased with straw supplementation (0.78 and 10.2 mmol/d). Daily weight gain of male lambs (but not of females) tended (P = 0.08) to be higher with whole barley than with the compound feed due to higher concentrate intake (P < 0.05), which was also depressed by straw supplementation of whole barley reducing the rate of gain (P = 0.06). Incidence of hyperparakeratosis and ulceration of rumen wall was high with all treatments (0.80 and 0.36) but papillary clogging was less frequent (P < 0.01) with whole barley (0.16) than with the compound feed (0.70) and tended (P = 0.01) to be reduced by straw supplementation. In Experiments 3 and 4 the proportion of protein supplements selected ranked in reverse order to their CP content, resulting in diets of similar CP concentration (180–200 g/kg DM). It is concluded that choice feeding of whole barley may be a practical alternative that offers some advantages over conventional compound feeding of growing lambs.  相似文献   


17.
Twenty four Duroc × Landrace male piglets, aged 21 days, were assigned to 1 of 4 experimental diets. Diets 1 and 2 contained 150 g kg− 1 wheat bran and diets 3 and 4 contained 90 g kg− 1 maize cobs as the major fibre source. All diets contained 480 g kg− 1 wheat and 200 g kg− 1 soybean meal. Diets 2 and 4 were supplemented with the following enzyme complex: 800 U/kg cellulase, 1800 U/kg glucanase and 2600 U/kg xylanase.

The replacement of wheat bran by maize cobs increased the acetic (P < 0.05) and decreased the butyric acid production (P < 0.05) in the cecum. Piglets fed diets with maize cobs had lower (P < 0.05) levels of butyric acid in the colon than those fed wheat bran.

The xylanolytic, pectinolytic and cellulolytic enzyme activities were higher (P < 0.05) in the cecum and colon of piglets fed the wheat bran based diets. The supplementation of the diet with the enzyme complex did not significantly affect the levels of short chain fatty acids formed in the small intestine and there was a non significant increase of the levels of acetic, propionic and butyric acids in the cecum and colon of piglets (P < 0.10). No interactions were present between fibre sources and enzyme addition.

The results suggest that the enzyme supplementation of the diet did not bring significant benefits to the animals and that when maize cobs replaces wheat bran in diets it negatively affects butyric acid production and fibre-degrading enzyme activity in the hindgut of piglets.  相似文献   


18.
An experiment was conducted in Nicaragua to determine the effect of feeding different levels of foliage from Moringa oleifera Lam (synonym: Moringa pterygosperma Gaertner) to dairy cows on intake, digestibility, milk production and milk composition. The treatments were: Brachiaria brizantha hay ad libitum, either unsupplemented or supplemented with 2 kg or 3 kg of Moringa on a dry matter (DM) basis. Six Bos indicus cows of the Creole Reyna breed, with a mean body weight of 394 ± 24 kg were used in a replicated 3 × 3 Latin square design. Supplementation with Moringa increased (P < 0.05) DM intake from 8.5 to 10.2 and 11.0 kg DM day− 1 and milk production from 3.1 to 4.9 and 5.1 kg day− 1 for B. brizantha hay only and supplementation with 2 kg and 3 kg DM of Moringa, respectively. Milk fat, total solids and crude protein and organoleptic characteristics, smell, taste and colour, were not significantly different between the diets. Apparent digestibility coefficients of DM, OM, CP, NDF and ADF increased (P < 0.05) in the diets supplemented with Moringa compared with B. brizantha hay alone. The results showed that the inclusion of Moringa as a protein supplement to low quality diets improved DM intake and digestibility of the diet and increased milk production but did not affect milk composition.  相似文献   

19.
Our goal was to determine the effect of diets with different crude protein (CP) contents and metabolizable energy (ME) levels on daily live-weight gain, apparent digestibility, and economic benefit of feedlot yaks on the Tibetan plateau during winter. Yaks were either 2- or 3-years old and randomly selected from the same herd. The 3-year-olds were placed into one of two experimental groups (A and B) and a control (CK1), and the two-year-olds were placed into one of three experimental groups (C, D and E) and a control (CK2) (N per group = 5). Yak in the control groups were allow graze freely, while those in the experimental groups yaks were fed diets higher in contains crude protein and metabolizable energy through a winter period inside a warming shed. Results indicated that live-weight gain of treatment groups was higher than their respective controls during experiment, and that daily live-weight gain of every 10 days among different treatments was significant difference (P < 0.05). In addition, apparent digestibility of different diets was linearly and positively related to feedlotting time, and feed conversion efficiency for A, C, D and E groups was quadratically related to feedlotting time (P < 0.01), however, feed conversion efficiency for B group was linearly and positively related to feedlotting time (P < 0.05). The economic benefit was 1.15 for A, 1.89 for B, 1.16 for C, 1.54 for D, and 4.52 for E.  相似文献   

20.
The impacts of using a modified farrowing pen (MOD) on the performance of sows and their litters and on ambient air quality over a hot and a cool season were evaluated. Primiparous Yorkshire × Landrace sows farrowed either during the months of February and March (thermoneutralily, TN) or June and July (heat-stress, HS). Temperatures within each season were controlled to 21 and 29 °C, respectively, for TN and HS. Animals from each group were assigned to a standard farrowing crate (STD; TN, n = 17; HS, n = 16) or a MOD pen (TN, n = 19; HS, n = 19). The MOD pen consisted of a STD crate with a 1.5 × 1.6-m comfort zone in the back, equipped with rubber floor mats, a feeder and a nipple waterer. Litter size was standardized to 10 or 11. No creep feed was provided and piglets were weighed weekly. Sows were weighed on days 2 and 22. Feed intake of sows was monitored daily, a milk sample was obtained on day 21 for compositional analyses and jugular blood samples were collected on days 2 and 21 to measure prolactin, IGF-I and urea. Sows consumed less feed (3.4 vs. 4.7 ± 0.1 kg/day, P < 0.001) in a hot than in a cool season and, at 29 °C, sows in MOD pens consumed more feed (3.9 vs. 3.0 ± 0.2 kg/day, P < 0.01) than sows in STD pens. Sow lactation weight loss was greater (− 26.4 vs. − 19.1 ± 1.9 kg, P < 0.05) for sows in STD than MOD pens in a hot season. The reduction in prolactin concentrations from days 2 to 22 of lactation tended to be greater (P = 0.08) in a hot season for sows in STD pens. Concentrations of urea and IGF-I increased as lactation advanced (P < 0.01) and IGF-I was lower for HS compared to TN sows on both days (P < 0.01), whereas urea was greater for HS sows on day 2 only (P < 0.01). Milk DM was less in a hot than in a cool season (P < 0.01). Average piglet weight gain was reduced in a hot compared to a cool season during the second week of lactation (P < 0.05) and this reduction was less in MOD than STD pens during the third week of lactation (P < 0.01). During a hot season, even though not significant, average weight gain of piglets from days 2 to 21 of lactation was reduced by 6.0% in MOD pens compared to 9.7% in STD pens.  相似文献   

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