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1.
The aim of the current study was to investigate the associative effects of a cornstalk-based diet supplemented with alfalfa (Medicago sativa) hay on intake, digestibility, nitrogen (N) metabolisation, rumen environment and hematological parameters in Xiaoweihan sheep. We also investigated the optimal range of alfalfa hay to achieve positive associative effects and avoid negative effects. Xiaoweihan sheep (n = 5; fitted with rumen T-cannula) were fed five cornstalk-based diets in a 5 × 5 Latin square design. Diets contained 0, 50, 150, 300, 450 g alfalfa, and were supplemented with 100 g concentrate, respectively. Our results suggested that supplementation of 300 g alfalfa hay reduced (P < 0.05) cornstalk intake, but significantly increased dry matter (DM) intake (P < 0.05). Additionally, DM digestibility of 150 g alfalfa hay supplementation was slightly higher than that noted in other diets. Metabolism studies showed 50–150 g alfalfa hay supplementation had a positive associative effect (P < 0.05) on N utilization, with the greatest benefit noted with 150 g per day (P < 0.05) compared to unsupplemented diets. Alfalfa supplementation (50–450 g per day) resulted in an elevated trend of ammonia nitrogen (NH3–N) with 50 or 150 g of alfalfa hay more likely to promote sheep rumen environment, with a noticeable increase (P < 0.05) in serum urea nitrogen (UREAN) concentrations observed with 300 g alfalfa hay per day. Our data suggested that the optimal range to achieve beneficial effects and avoid negative effects was 150–300 g per day for cornstalk-based diets for sheep.  相似文献   

2.
The effects of feeding graded levels of dried moringa (Moringa stenopetala) leaf on intake, body weight gain (BWG), digestibility and nitrogen utilization were studied using male sheep (BW of 13.8 ± 0.12 kg). Six sheep were randomly allocated to each of the four treatment diets: Rhodes grass (Chloris gayana) hay offered ad libitum (T1), hay + 150 g moringa leaf (T2), hay + 300 g moringa leaf (T3), hay + 450 g moringa leaf (T4) were offered daily. A 7-day digestibility trial and an 84-day growth experiments were conducted. Dry matter (DM), organic matter (OM) and crude protein (CP) intakes increased (P < 0.05) with increasing levels of moringa leaf in the diets. Sheep fed T2, T3 and T4 diets gained (P < 0.05) 40.2, 79.1 and 110.1 g/head/day, respectively, while the control group (T1) lost weight (−13.3 g/head/day). The apparent digestibilities of DM, OM, neutral detergent fibre and acid detergent fibre were similar (P > 0.05) among treatments. The digestibility of dietary CP increased (P < 0.05) with increasing levels of moringa leaf, but there was no significant difference between T2 and T3 diets. The nitrogen (N) intake and urinary N excretion increased (P < 0.05) with increasing levels of moringa leaf. The N retention was highest (P < 0.05) for 450 g moringa leaf supplementation. The control group was in a negative N balance. Supplementing a basal diet of Rhodes grass hay with dried moringa leaves improved DM intake, BWG and N retention. It is concluded that M. stenopetala can serve as a protein supplement to low-quality grass during the dry season under smallholder sheep production system.  相似文献   

3.
The effects of feeding different levels of forages and concentrate, in a discontinuous feeding pattern, on the efficiency of feed utilisation and rumen function were studied using rumen fistulated sheep. Experiment 1 was a 4 × 4 latin square design to determine the whole tract digestibility and rumen characteristics of diets comprising 15% (C15), 25% (C25), 35% (C35) and 45% (C45) concentrate (energy-dense dairy pellets) with the rest of the diet being a combination of fresh short rotation ryegrass (Lolium mutiforum) and conserved (lucerne hay and maize silage) forages. In Experiment 2, the rumen degradation characteristics of feed ingredients were determined using the nylon bag technique. Daily dry matter intake (either expressed as g/kg LW or g/kg W 0.75) was 10% lower (p = 0.03) for the C15 diet compared with C25, C35 and C45 diets. The apparent in vivo digestibility of dry matter (DM) for C15 diet was 4% higher (p = 0.04) than the C35 and C45 diets which may be attributed to the high quality of the forage (ryegrass) used.Fibre digestibility decreased as proportion of concentrate in the diet increased. However, this was unlikely due to changes in the rumen fermentation pattern, as neither pH (6.1 ± 0.23) nor ammonia concentration (24.4 ± 6 mg/dl), were different (p > 0.05) among diets. Instead, the lower fibre digestion was most likely the result of different type and proportion of fibre among diets, as total rumen degradability and rate of fibre degradation in the rumen were higher (p = 0.001) for ryegrass than for other feedstuffs. There was no significant difference in total nitrogen balance and urinary allantoin excretion among diets, which indicated similar total microbial protein synthesis (MPS). The asynchrony observed, for N and energy availability in the rumen for different diets using Sinclair et al. [Sinclair, L.A., Garnsworthy, P.C., Newbold, J.R., Buttery, P.J., 1993. Effect of synchronizing the rate of dietary energy and nitrogen release on rumen fermentation and microbial protein synthesis in sheep. J. Agric. Sci. 120, 251–263] equation, was due to the feeding pattern used in this study leading to excess of N in relation to total organic matter digested in the rumen. In conclusion, feeding concentrates in the diets as PMR with conserved forages in a discontinuous feeding pattern may be valuable to develop feeding strategies in a pasture based system for high producing dairy cows without affecting the rumen system.  相似文献   

4.
Two in vivo digestibility trials with sheep were conducted to identify the minimum period length of feeding a new diet to obtain reproducible values of nutritional variables onward and the minimum length of collection period as to obtain maximal precision for each variable. Trial 1 was conducted with ten Polwarth male sheep (34 ± 5 kg body weight (BW)) throughout three 21‐day periods, in a completely randomized two‐way crossover design. The animals were divided into two groups (Group A and B, n = 5 per group) which were fed ad libitum with a sequence of the following diets throughout the periods: Group A: hay – hay plus concentrate – hay; Group B: hay plus concentrate – hay – hay plus concentrate. The concentrate was included in a proportion of 0.33 of the total diet. The intake, and the faecal and urinary excretion were measured daily throughout the experiment. For evaluating rumen fermentation variables, in Trial 2 four Santa Inês male sheep (65 ± 5 kg BW) fitted with ruminal cannula were used. The animals were randomly divided into two groups (n = 2 per group), and the trial was conducted through four 21 days experimental period, in a three‐way crossover design, using experimental diets and feeding management similar to Trial 1. The results indicated that, even though no clear or consistent steady‐state condition was identified for rumen fermentation or urinary excretion variables, the adaptation period for measuring OM digestibility in in vivo trials with sheep fed ad libitum where the diet shifts from one of only hay to another containing concentrate, or vice‐versa, should be at least 12 days long. Moreover, although no precision improvement was obtained by increasing the collection period above 1 day for measuring OM digestibility, the minimal length of collection period should be 4 days for measuring faecal excretion variables and 7 days for measuring urinary excretion variables.  相似文献   

5.
The aim of this study was to investigate the effects of different levels of Desmodium intortum (Desmodium) hay supplementation in sheep fed fixed amounts of enset pseudostem or corm and a basal diet of wheat straw on intake, digestibility and nitrogen utilization. Eighteen male sheep with a mean (± SD) live weight of 20.5 ± 1.45 kg were assigned to six treatments in a completely randomized design and fed either 108 g dry matter (DM) enset pseudostem or 165 g DM enset corm each with three levels (100, 200 and 300 g) of hay supplementation. For the pseudostem diets, there was no significant difference in total DM intake. Total crude protein (CP) intake and N retention increased with increasing levels of hay in both pseudostem and corm diets. The apparent digestibility of DM, OM, CP, acid detergent fibre and neutral detergent fibre (NDF) and microbial nitrogen supply (MN) at 100 g was lower that other levels of supplementation. For the corm diets, total DM and OM intake and MN supply increased with increasing levels of hay. The digestibility decreased (p < 0.001) with increasing levels of supplementation. The results suggest that at least 300 g (395 g/kg dietary DM) of Desmodium hay is required in pseudostem diets, whereas 200 g (337 g/kg dietary DM) may be sufficient in corm diets for efficient nutrient utilization.  相似文献   

6.
In this study, the possibility of using Babassu (Orbignya phalerata) and Mofumbo (Combretum leprosum) leaves for lambs feed was verified. Performance, biochemical and haematological parameters, microbial protein synthesis, nutrient apparent digestibility and enteric production of methane (CH4) were evaluated. The experimental treatments included diets with forage‐to‐concentrate ratios of 50:50, with the leaves of the experimental plants replacing 33% of the Cynodon dactylon (Tifton‐85) hay with three treatments: control (no hay replacement) and substitution with Babassu or Mofumbo. For the performance study, 24 Santa Inês lambs were used, in a randomized experimental design with eight repetitions (5 male and 3 female) for each treatment and 48 days of experimental trial. After this period, for nine days, six animals from each treatment were allocated in metabolic cages to determine the apparent nutrient digestibility, microbial protein synthesis and nitrogen balance. Simultaneously, enteric CH4 was measured in vivo. The control group showed higher (p < 0.05) apparent digestibility of acid detergent fibre. Enteric CH4 production of lambs fed Mofumbo leaves did not differ from that of the control group, but was lower (p < 0.05) than in those fed with Babassu. The inclusion of Babassu and Mofumbo leaves showed no negative effects on animal health and did not compromise performance. Mofumbo also presented CH4 mitigating potential, indicating that those plants can be used as ingredients in the composition of lamb diets with the advantage of reducing methane production.  相似文献   

7.
The effects of supplementing ewe diets with either DL‐methionine (DL‐Met) or 2‐hydroxy‐4 (methylthio) butanoic acid isopropyl ester (HMBi) were investigated on ruminal in situ degradability of grain and forage diets, in vivo digestibility, rumen fermentation, blood metabolites and antioxidant status. Six ruminally cannulated ewes were used in a replicated 3 × 3 Latin square design with 28‐day periods. The dietary treatments were as follows: (i) no supplemental Met (control; CON), (ii) DL‐Met at 1.2 g/kg DM intake and (iii) HMBi at 1.8 g/kg dry matter (DM) intake. Corn grain, barley grain and alfalfa hay were evaluated for their ruminal degradability by both in situ incubation and effective degradability measurements of DM, neutral detergent fibre (NDF) and acid detergent fibre (ADF). Compared to other treatments, HMBi supplementation increased (p < 0.05) the digestibility of organic matter, crude protein and NDF and also tended (p = 0.08) to increase the digestibility of DM and ADF. Moreover, HMBi supplementation increased (p < 0.01) total VFA concentrations, the molar proportions of valerate and iso‐butyrate in the rumen. Compared to the CON treatment, DL‐Met and HMBi treatments tended (p = 0.08) to increase the molar proportion of acetate but decreased (p < 0.05) ruminal ammonia‐N concentration. Ewes supplemented with HMBi and DL‐Met recorded greater (p < 0.05) serum concentrations of glutathione peroxidase, total antioxidant capacity and superoxide dismutase than the CON treatment. Serum concentrations of glucose, total protein, albumin, high‐density lipoprotein and very low‐density lipoprotein were greater (p < 0.01) and serum urea nitrogen (p < 0.05), malonyl dialdehyde and triglyceride were lower (p < 0.02) in the HMBi and DL‐Met animals than in the CON ewes. The results concluded that HMBi is a very effective form of dietary Met supplementation for ewes with a positive effect on digestion, rumen fermentation and serum antioxidant function.  相似文献   

8.
This study aimed to investigate the effects of replacing alfalfa hay (AH) with a mixture of cassava foliage silage and sweet potato vine silage (CSP) (1:1 on a dry matter (DM) basis) on ruminal and intestinal nutrient digestion in sheep. Four wethers were fed a control diet containing 35% of AH and two treatment diets containing 15% and 30% of the CSP as substitute for AH at 1.5 times the metabolizable energy required for maintenance. Replacing AH with the CSP silage did not affect DM intake, whereas it linearly increased (P < 0.05) the intake of ether extract and acid detergent insoluble nitrogen (ADIN). Increasing the CSP substitution linearly decreased (P < 0.05) ruminal DM and neutral detergent fiber (aNDFom) digestibility; however, it did not affect total tract aNDFom digestibility. The CSP substitution did not affect nitrogen (N) intake and duodenal total N flow, whereas it linearly increased duodenal ADIN flow (P < 0.01) and decreased ruminal ammonia‐N concentration (P < 0.01), and intestinal (P = 0.08) and total N digestibility (P < 0.01). These results indicate that replacing AH with the CSP reduced the ruminal N degradation as well as the digestion of ruminal aNDFom and intestinal N.  相似文献   

9.
This study aimed to evaluate the effects of forage neutral detergent fiber (fNDF) levels on the voluntary feed intake, digestibility, ruminal fermentation and feeding behavior of goats fed diets with cactus pear. Five non‐lactating ruminally cannulated goats fed ad libitum were randomly assigned to a 5 × 5 Latin square design. Treatments consisted of levels of fNDF at 0, 109, 222, 339 and 463 g/kg of dry matter (DM) in cactus pear‐based diets. The intakes of DM and NDF were quadratically affected (p ≦ .045) by fNDF levels. Voluntary water intake (VWI) increased linearly as the fNDF levels increased in the diet. The digestibility coefficients of organic matter, NDF and ether extract and total digestible nutrients concentration were quadratically affected (p ≦ .048) by fNDF levels. The ruminal pH linearly increased (p = .001) with fNDF levels, ranging from 5.44 to 5.81 for diets containing 0 and 463 g fNDF/kg DM, respectively. The fNDF levels promoted a linear increase (p = .006) in chewing time, linearly decreased (p = .007) resting time and quadratically affected (p = .033) rumination time. The inclusion of fNDF in the diets provided favorable conditions for ruminal function, digestibility and feeding behavior in goats fed diets containing cactus pear.  相似文献   

10.
This study was conducted to evaluate the effects of increasing levels of wasted date (WD) in sheep (initial body weight 50 ± 2.3 kg) diets on apparent diet digestibility, rumen fermentation and microbial protein synthesis. The experimental diets contained 0 (0 WD), 9% (9 WD), 18% (18 WD) or 27% (27 WD) of wasted dates. These diets were evaluated through a 4 × 4 Latin square design with four 28‐day periods. Sheep were individually housed in metabolic cages and were fed diets ad libitum. To keep the diets isoenergetic and isonitrogenous, increasing partial replacement of WD for barley grain was used with increasing levels of soya bean meal. Increasing the amount of WD in diets of sheep did not influence (p > 0.05) diet intake and digestibility of nutrients. Inclusion of WD in diets of sheep did not affect (p > 0.05) ruminal pH but decreased (p < 0.05) NH3‐N concentration and blood urea nitrogen. Also there was no effect (p > 0.05) of the WD provision on N intake and faecal N loss of experimental animals, but urinary nitrogen excretion and retained nitrogen were affected (p < 0.05) by dietary treatments. Purine derivatives and microbial protein synthesis increased (p < 0.05) linearly with the level of WD in the diet. In conclusion, the increase in microbial protein synthesis and concomitant reduction in ruminal NH3‐N concentration and blood urea nitrogen in response to wasted date supply suggest improved efficiency of ruminal nitrogen metabolism without adverse effects on fermentation characteristics and animal performance.  相似文献   

11.
The effects of forage type and forage:concentrate ratio (F:C) on apparent nutrient digestibility, ruminal fermentation, and microbial growth were investigated in goats. A comparison between liquid (LAB) and solid (SAB)-associated bacteria to estimate microbial N flow (MNF) from urinary purine derivative excretion was also examined. Treatments were a 2 x 2 factorial arrangement of forage type (grass hay vs. alfalfa hay) and high vs. low F:C (70:30 and 30:70, respectively). Four ruminally cannulated goats were fed, at maintenance intake, 4 experimental diets according to a 4 x 4 Latin square design. High-concentrate diets resulted in greater (P < 0.001) nutrient digestibility except for ADF. However, CP digestibility increased (P < 0.001) only for the high-concentrate diets including grass hay. Likewise, N retention, ruminal NH(3)-N concentration, and urinary excretion of purine derivatives increased (P < 0.05) with increasing concentrate in animals fed diets based on grass hay (0.23 vs. 0.13 g of retained N/g of digested N, 30.1 vs. 12.9 mg of NH(3)-N/100 mL, and 11.5 vs. 8.40 mmol/d, respectively), but not (P > 0.05) when diets included alfalfa hay. Total protozoa numbers and holotricha proportion were greater and less (P < 0.001), respectively, in high- than in low-concentrate diets. The F:C affected (P < 0.001) ruminal pH but not total VFA concentration (P = 0.12). Ammonia-N concentration was similar (P = 0.13) over time, whereas pH, VFA concentration, and protozoa numbers differed (P < 0.001) among diets. Estimated MNF was strongly influenced by using either the purine bases:N ratio obtained in our experimental conditions or values reported in the literature for small ruminants. There was a F:C effect (P = 0.006) on MNF estimated from LAB but not from SAB. The effect of F:C shifting from 70:30 to 30:70 in goat diets depends on the type of forage used. The MNF measured in goats fed different diets was influenced by the bacterial pellet (LAB or SAB). In addition, the purine bases:N ratio values found were different from those reported in the literature, which underlines the need for these variables to be analyzed directly in pellets isolated from specific animals and experimental conditions.  相似文献   

12.
The objective of this study was the characterization of the nutritive value, ruminal fermentation and nutrient digestibility of field pea (Pisum sativum L.) hay (FPH) by‐product through in situ, in vitro and in vivo tests. A FPH diet was administered ad libitum to four sheep (live weight (LW) 38.0 ± 2.0 kg) at four inclusion levels (0, 25, 50 and 75%) over a conventional sorghum grain/oat straw ration in a 4 × 4 Latin square design. The in situ degradability of FPH was 67% dry matter (DM), 71% crude protein and 66% neutral detergent fiber (NDF). The inclusion of FPH did not affect (P ≥ 0.05) the DM (61 ± 0.4 g/LW0.75/day) and organic matter (OM) intake (56 ± 0.7 g/LW0.75/day). Total DM digestibility (68 ± 2.5%), OM (70 ± 3%), and NDF (60 ± 3%), were not different (P ≥ 0.05) between control and FPH inclusion diets. The diet had no effect on ruminal pH, ruminal ammonia concentration, total and individual volatile fatty acids. The chemical composition and sheep intake behavior indicate that FPH by‐product is medium quality forage when incorporated in maintenance rations.  相似文献   

13.
This study aimed to evaluate the substitution of imported corn and soybean by local feed resources from tropical production settings such as entire green banana and Gliricidia sepium forage as energy and protein sources, respectively, in sheep diets. Two experiments were conducted: first, a ‘growth trial’ and second, an in vivo digestion study. In the ‘growth trial’, 40 Martinik lambs [body weight (BW): 29.4 ± 3.6 kg; 6 months old) were used and distributed into four groups of 10 lambs each according to treatment: HBGl (banana + gliricidia at low level; 1500 g/day; 119 g/kg BW0.75), HBGh (banana + gliricidia at high level; 3000 g/day; 238 g/kg BW0.75), HBS (banana + soybean cake) and Control (corn + soybean cake). In digestion trial, four Martinik rams (BW: 57.2 ± 3.45 kg) fitted with ruminal and duodenal cannulae were used; treatments (HBG, HBS and Control) were similar but adjusted to metabolic body weight (MW) and just one level of gliricidia was used. Intake, average daily gain (ADG), feed intake to gain index (F:G), apparent total and ruminal digestibilities as well as nitrogen balance, microbial efficiency and volatile fatty acid (VFA) profile were monitored. Lambs fed HBGh had greater dry matter (DM) intake based on MW and ADG (173 g/day vs. 141 g/day; p < 0.001), whereas HBGl lambs showed the lowest ADG (71.5 g/day) and the worst F:G (14.4; p < 0.001). The DM, organic matter (OM), neutral detergent fibre and acid detergent fibre digestibilities were not influenced by treatment, whereas crude protein digestibility was higher (p = 0.024) in diets offered banana or corn + soybean cake (687 g/kg DM and 658 g/kg DM, respectively). Ruminal DM and OM digestibilities did not differ among treatments. Total or individual VFA concentrations were also not influenced by the diet. Higher (p = 0.006) ruminal fluid pH values were recorded for diets combining banana and gliricidia (6.54) or banana and soybean (6.39) until 3 h after a meal. As all animals on gliricidia‐ and banana‐supplemented diets gained weight and maintained a positive N balance, it is concluded that green banana and gliricidia forage may be a viable alternative to replace conventional energy and protein supplements in sheep diets.  相似文献   

14.
Effects of NaHCO3 and MgO buffer addition on intake and digestive utilization of a pasture were studied in wethers allowed a restricted time of access to forage. Twelve wethers housed in metabolic cages and fed fresh forage (predominantly Lotus corniculatus) ad libitum for 6 h/d were randomly assigned to one of the following treatments: a control forage without buffer (C) or a forage plus buffer composed of a mixture of 750 g/kg NaHCO3 and 250 g/kg MgO at 20 g/kg dry matter intake (B). Feeding behaviour, feed and water intake and digestibility, urine output, Na urine elimination, kinetics of passage, ruminal pH and ammonia concentration, N balance and ruminal microbial N synthesis were determined in vivo, and the ruminal liquor activity was evaluated in vitro by fermentation of wheat straw. Addition of buffer increased total water intake (p = 0.05), Na urinary output (p = 0.01), purine derivative excretion in urine (p = 0.05) and tended to decrease mean total retention time in the digestive tract (p = 0.09). However, buffer addition increased ruminal pH (p < 0.001) and tended to decrease the ammonia concentration (p = 0.05). That use of buffer decreased ruminal activity was evidenced by a lower volume of gas produced in vitro (p = 0.01) possibly due to a lower microbial concentration in rumen liquor. The higher rumen dilution rate, likely due to a higher water intake, seems to have been the key driver of the actions of buffer supplementation on the rumen environment. Moreover, addition of NaHCO3 led to an increased urinary Na excretion, which should be considered due to its likely negative environmental impacts.  相似文献   

15.
Growth and digestibility experiments were conducted on growing East African type goats offered Chloris gayana hay supplemented with one of three high-protein (119–128 g CP/kg DM) legume hays, Cassia rotundifolia (cassia), Lablab purpureus (lablab) or Macroptilium atropurpureum (siratro), and crushed maize to investigate the feed intake, digestibility, growth and urinary excretion of purine derivatives. Goats in the supplemented groups had higher total dry matter and nitrogen intakes and higher N retention and body mass gains than unsupplemented counterparts. The digestibility of dry matter, organic matter and neutral detergent fibre were increased by protein supplementation. Animals on supplemented diets had higher fractional outflow rates of particulate matter from the rumen. The production of protein by ruminal microbes and the efficiency of microbial N production were increased by supplementation. It was concluded that a mixture of low-quality grass hay (61.9 CP/kg DM) and either cassia, lablab or siratro hay, and maize grain can provide a productive balanced diet for growing goats.  相似文献   

16.
Restricted feeding and high concentrate diets are potential strategies for growing dairy heifers. Ruminal manipulation with additives such as Saccharomyces cerevisiae yeast culture (YC) has been shown to alter digestibility when added to this type of diet. An experiment was conducted to investigate the ruminal fermentation and in situ digestibility of diets with 3 different levels of forage to concentrate (F:C) fed at restricted intake without and with YC addition. Three cannulated post-pubertal Holstein heifers (age 18.0 ± 1.2 months; body weight 449.6 ± 19.7 kg) were fed diets consisting of corn silage as the sole forage source in a 3 period (35-day) Latin square design. Heifers were fed diets for 21 days with no YC addition, followed by 14 days where YC was added to the diet (1 g/kg as fed basis). Low (LC), medium (MC), and high (HC) concentrate diets (20, 40, and 60% concentrate) were fed once daily on a restricted basis to provide 0.22 Mcal ME/kg empty BW0.75. Rumen fluid was sampled on days 18 and 32 of each period, and rumen contents were evacuated on days 21 and 35 of each period. An in situ study was done on days 14 to 17 and on days 28 to 31. Mean ruminal pH was not different between dietary treatments and no YC effect was detected. Mean total volatile fatty acids (VFA) and ruminal ammonia-nitrogen (NH3-N) concentration was also not different among diets with different F:C. Molar proportions of acetate were decreased, and propionate were increased; while the acetate-to-propionate ratio was decreased as the concentrate level increased from LC to HC. Total VFA, propionate, and acetate as well as isoacids concentration increased, yet NH3-N concentration decreased with YC addition in all diets. From these results we conclude that feeding HC diets in restricted amounts had minimal effects on rumen fermentation rate between different F:C diets. The addition of YC modified NH3-N and volatile fatty acid concentrations in the rumen in all 3 diets in this study, presumably through alterations in end-product production and utilization.  相似文献   

17.
This study was conducted to examine the effect of date palm (Phoenix dactylifera L.) seed (DPS) on the performance, ruminal fermentation, antioxidant status and milk fatty acid (FA) profile of dairy goats. Eight multiparous Saanen dairy goats, averaging 97 ± 7 days in milk (DIM) and 2150 ± 130 g of milk production, were used in a 4 × 4 replicated Latin square design. Experimental diets contained 0% (control), 6% (DPS6), 12% (DPS12) and 18% (DPS18) of DPS. Dry matter intake (DMI), milk production, and the composition and digestibility of the dry matter (DM), organic matter (OM), neutral detergent fibre (NDF) and crude protein (CP) were not affected by the diets. Adding DPS to the diet increased linearly total antioxidant capacity (TAC) in milk and blood (p < 0.05). No significant difference was found in the malondialdehyde (MDA) content in milk and blood. Superoxide dismutase (SOD) and glutathione peroxidase (GSH‐Px) activities in the blood, ruminal pH, NH3‐N, ruminal total volatile fatty acid (VFA), acetate, butyrate, isovalerate and valeric acid concentration had no significant effect among the diets. The propionate acid concentration decreased linearly as DPS was added to the diet, and DPS18 had minimum propionate acid concentration (p < 0.05). The inclusion of DPS18 to diets increased linearly the proportion of C18:0 (compared to control) as well as cis‐18:1, trans‐18:1 (compared to control and DPS6) and decreased C14:1 (compared to control) in milk fat (p < 0.05). The concentration of conjugated linoleic acid (CLA) in DPS18 was higher than other diets (p = 0.04). The results of this study implied that replacing DPS with a part of dairy goats’ ration had no negative effects on the performance of the animals and could also improve the antioxidant activity and increase the concentration of CLA in their milk.  相似文献   

18.
The study assessed the value of Leucaena leucocephala bark in leucaena—grass hay diets fed to Thai goats. Thai goats in metabolism pens were fed diets containing leucaena leaf (55%) + pangola grass hay (hay, 45%); leucaena leaf (48%) + leucaena bark (9%) + hay (43%); leucaena bark (57%) + hay (43%); and hay only. Feed percentages are expressed on a dry weight basis. The digestibilities of dry matter (DM) and crude protein (CP) were measured for the four diets. Leucaena bark had lower CP concentration than the leaf (11.7 vs. 25.9), and the leucaena bark + hay diet had lower DM and CP digestibility than the other diets. The calculated bark digestibilities of DM and CP of 44.1% and 38.2%, respectively, were much lower than the values for the leucaena leaf of 62.9% and 89.1%, respectively. The lower than expected CP digestibility was attributed to higher tannin levels in the bark compared to the leaves. Despite this, the bark was well accepted by the goats and was often preferred to the hay. Stripping of the bark by goats also results in stems that dry quicker and have higher calorific value as fuel. However, if leucaena branches are fed as a sole diet, the goats may consume up to 30% of bark on a DM basis and this would reduce nutritive value and animal productivity.  相似文献   

19.
A study to determine the nutritive value of mulberry (Morus alba) leaves in sheep diets was conducted. Mulberry leaves contained (g kg−1 on dry matter basis): 163 ash, 201 crude protein, 120 crude fibre, 37 ether extracts, 479 nitrogen-free extracts, 268 neutral detergent fibre, 148 acid detergent fibre, 41 acid detergent lignin, 121 cellulose and 107 hemicellulose, while the in vitro true digestibility of dry matter was 89.8%. The nitrogen (N) solubility, determined using: a) McDougall’s buffer, b) 0.02 N sodium hydroxide (NaOH) and c) 0.15 N sodium chloride (NaCl) as solvents, ranged from 11.6 to 14.9% of total N. In addition, the soluble non-protein nitrogen contributed a substantial part of total N (26.1%), the total true protein was 14.4% and the protein fractions evaluated after classical protein fractionation, were: albumins 11.1, globulins 9.7, prolamins 44.1, glutelins 8.5 and insoluble (or structural) proteins 26.6% of total N. In a digestibility trial, where mulberry leaves partially replaced lucerne hay and concentrates in wether sheep diets, there were no significant differences in dry matter, crude protein or crude fibre digestibility of the total diet. It was concluded that mulberry leaves have an appreciable potential as a protein source in sheep feeding.  相似文献   

20.
The present study investigated the effects of dietary forage source (quality) and particle size on chewing activity, saliva secretion, and ruminal pH. Twelve multiparous lactating Holstein cows, four of which were ruminally cannulated, were used in a replicated 4 × 4 Latin square experimental design with a 2 × 2 factorial arrangement of treatments. Cows fed wild‐rye hay diets had longer daily eating times than cows fed oaten hay diets. Treatments had no effect on ruminating time; therefore, resting time varied inversely to eating time. Neither the rate nor the amount of saliva secretion while eating, ruminating, or resting was affected by diet, resulting in similar total daily saliva secretions across treatments (231 L/day). Total volatile fatty acids (VFAs) in the ruminal fluid from animals fed oaten hay diets were higher than those from animals fed wild‐rye hay diets; further, VFAs increased with decreasing forage particle size (FPS). Consistent with elevated VFA concentrations, reducing FPS and including oaten hay in the diet decreased mean ruminal pH and increased the daily time of ruminal pH under 5.8. Results of this study suggest that forage source and particle size affect ruminal pH might be via variations in VFA production rather than increased salivary recycling of buffering substrates.  相似文献   

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