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71.
The aim of this study was to assess the effects of feeding Atriplex halimus (AH) silage treated with two developed enzyme cocktails to sheep on feed intake, nutrient digestibility and ruminal fermentation. The AH silage was treated without or with 2 L of ZAD1® or ZAD2®/1000 kg with 5% molasses and ensiled for 30 days. Barley grain (300 g/head/day) was fed as an energy supplement once daily at 10.00 hours and AH silage with or without enzyme treatment was offered ad libitum to animals twice daily at 09.00 and 16.00 hours. Sheep were fed on four experimental forage diets comprised of AH silage and barley (D1), AH silage treated with ZAD1® and barley (D2), AH silage treated with ZAD2® and barley (D3) and AH silage treated with a combination of ZAD1® and ZAD2® (1:1) and barley (D4). Ensiling AH with enzymes reduced its contents of neutral detergent fiber and acid detergent fiber. The dry matter intake of AH of D2, D3 and D4 decreased (P < 0.001) as compared to D1. However, enzyme‐treated diets had greater total digestible nutrients intake (P < 0.001) as compared to D1. The nutrients digestibility for D2, D3 and D4 were higher than those for D1 (P < 0.001), and were higher for D3 as compared to both D2 and D4. Sheep fed on D3 had highest (P < 0.001) ruminal total volatile fatty acids concentration, ammonia nitrogen concentration and microbial protein yield. It could be concluded that AH silage treated with ZAD1® or ZAD2® improved digestibility and rumen fermentation in sheep.  相似文献   
72.
Four wethers were used in a 4 × 4 Latin square design experiment to evaluate in vivo digestibility of total mixed ration (TMR) silage with food by‐products for dairy cows, and the ruminal condition and nitrogen (N) balance were examined. Five by‐products (i.e. potato waste, noodle waste, soybean curd residue, soy sauce cake and green tea waste) were obtained. Four types of TMR silage were used: control (C) containing roughage and commercial concentrate, T1:20% and T1:40% containing the five by‐products replacing 20% and 40% of the commercial concentrate on a dry matter (DM) basis, respectively, and T2:40% containing three by‐products (potato waste, noodle waste and soybean curd residue) replacing 40% of the commercial concentrate on a DM basis. The ingredients were mixed and preserved in oil drum silos for 4 months. The TMR silages showed 4.02–4.44% and 1.75–2.19% for pH and lactic acid contents, respectively. The digestibility of DM and neutral detergent fiber, and total digestible nutrient content were higher (P < 0.05) for T2:40% feeding than for C feeding. Urinary nitrogen excretion tended to be lower (P = 0.07) for T2:40% than for C. The results suggested 40% replacing of commercial concentrate by using the three food by‐products can be most suitable for TMR silage.  相似文献   
73.
This experiment was conducted to study the effects of different levels of compound Chinese medicine on growth performance,nutrients apparent digestibility,immune function and slaughter performance of weaning Rex rabbits.70 healthy Rex rabbits at age of 60 days were divided into 7 groups with 5 replicates per group and 2 rabbits per replicate.Group Ⅰ was fed with basic diet as control group,group Ⅱ was fed the basal diet supplemented with antibiotic (contains 50 mg/kg milligrams bacitracin zinc,10 mg/kg colistin sulfate).The other five groups (Ⅲ,Ⅳ,Ⅴ,Ⅵ and Ⅶ) were fed the basal diet supplemented with 1%,2%,3%,4%,5% compound Chinese medicine,respectively.The pre-test period lasted for 7 days and the trial period lasted for 45 days.The results showed as follows:①The ADG in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ and Ⅲ (P< 0.05),the F/G in group Ⅳ was significantly lower than that in other groups (P< 0.05).②The apparent digestibility of DM in group Ⅳ was significantly higher than that in groups Ⅰand Ⅱ (P< 0.05),the apparent digestibility of DM in group Ⅶ was significantly higher than that in group Ⅰ (P< 0.05).The apparent digestibility of CF in group Ⅳ was extremely significantly higher than that in group Ⅰ (P< 0.01),the apparent digestibility of CF in group Ⅶ was significantly higher than that in group Ⅰ (P< 0.05).The apparent digestibility of NDF in group Ⅳ was extremely significantly higher than that in group Ⅰ (P< 0.01),and significantly higher than that in groups Ⅱ,Ⅲ,Ⅴ and Ⅶ (P< 0.05).The apparent digestibility of ADF in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ,Ⅴ and Ⅶ (P< 0.05).The apparent digestibility of CP in group Ⅳ was significantly higher than that in groups Ⅰ and Ⅱ (P< 0.05).③ There were no significant differences in the contents of IgG,IgA and IgM of serum among all groups (P> 0.05),the spleen index in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ,Ⅲ and Ⅴ (P< 0.05).④There were no significant differences in the slaughter rate,half eviscerated slaughter rate and all eviscerated slaughter rate among all groups (P> 0.05).In summary,adding compound Chinese medicine and antibiotics in the feed both could improve the growth performance,nutrients apparent digestibility,immune function and slaughter performance of weaning Rex rabbits,and the appropriate compound Chinese medicine level in the diet of weaning Rex rabbits was 2%.  相似文献   
74.
An in vitro method was developed to assess the digestibility of phosphorus in 12 plant and animal feed ingredients for rainbow trout Oncorhynchus mykiss (Walbaum). The method simulates the gastrointestinal tract of the rainbow trout with regard to pH and gastrointestinal enzymes. Phosphorus solubility was measured after acid digestion (pH 3) with and without gastric enzymes, after alkaline digestion (pH 9) with and without intestinal enzymes, and after a two-step process involving acid and alkaline digestion. Commercially available digestive enzymes from mammals were compared with digestive enzymes from rainbow trout. Correlating in vitro digestibility with in vivo digestibility showed that acid digestion with both commercial enzymes ( r 2=0.98, P  < 0.05) and trout enzymes ( r 2=0.94, P  < 0.05) predicted the in vivo digestibility of animal feed ingredients. Alkaline digestion with both enzyme systems (commercial r 2=0.79; trout r 2=0.74, P  < 0.05) or without ( r 2=0.82, P  < 0.05) enzymes predicted the in vivo digestibility of ingredients from animal byproducts but not those from plant products. The in vitro digestibility with two enzyme steps (acid and alkaline) predicted in vivo digestibility of plant and animal ingredients ( r 2=0.79 for commercial enzymes and r 2=0.74 for trout enzymes) better than did one-step acid or alkaline digestion.  相似文献   
75.
76.
Strategies for further development of aquatic feeds   总被引:4,自引:1,他引:4  
ABSTRACT: To date, aquatic feeds have depended heavily on fishmeal and fish oil as their source of protein and lipid. However, the feed industry is encountering shortfalls in the availability of these ingredients because of a decline in the number of fish captured in the wild and the increased human demand for some of the species currently being used for fishmeal and oil production. Therefore, efforts are now being directed in different parts of the world to finding alternative quality ingredients, which ideally are less expensive and readily available for use in practical diets. The data accrued have shown that a large proportion of both fishmeal and fish oil can be replaced by other protein and lipid sources. However, it is emphasized that an optimal essential amino acid balance be maintained and that the n-3 highly unsaturated fatty acid requirement be satisfied when combining economical protein and lipid ingredients. Newly developed feeds should aim at being nutrient-dense in order to reduce the output of solid, P and N waste. This can be done through improving nutrient availability, optimizing the digestible protein to energy balance of the diet, and replacing dietary fishmeal with alternate ingredients. These diets should also be effective for maintaining good health and improving disease resistance in fish through enhancement of immune responses. A wholesome approach to culturing fish would be to use appropriate feeding standards that are aimed not only at improving economic returns but also at developing a lasting cohabitation of sustainable aquaculture and a cleaner environment. Furthermore, in the 2lst century aquaculture would still retain its place as a prominent source of food protein, signifying that fish feed research remains a forceful area in discovering better feeds for the industry.  相似文献   
77.
The objective of the present study was to investigate if dietary soluble non‐starch polysaccharides (NSP) increase digesta viscosity, reduce nutrient digestibility and increase organ weights in African catfish. The fish (mean weight 80 g) were fed diets supplemented with the soluble NSP guar gum at three levels, 0 g kg?1 (GG0), 40 g kg?1 (GG4) and 80 g kg?1 (GG8). Guar gum inclusion significantly increased digesta viscosity in the proximal (GG0: 1.7 centipoise or cP; GG4: 84.9 cP; GG8: 98.3 cP) and distal (GG0: 1.9 cP; GG4: 109.8 cP; GG8: 66.4 cP) intestine. Apparent digestibility coefficients (ADC) were significantly lower for the GG8 diet than the GG0 diet (dry matter: 52% versus 69%; protein: 77% versus 90%; ash: 41% versus 54%; energy: 60% versus 77%). The ADC of dry matter and energy were significantly lower for the GG4 diet than the GG0 diet. The relative growth rate of metabolic weight (14.5–15.4 g kg?0.8 day?1) and feed conversion ratio (0.8) did not differ between diets. Fish fed the GG8 diet had a significantly higher somatic stomach index than GG0 fish (0.71% versus 0.65% body weight). The intestinal somatic index tended to increase with increasing guar gum supplementation (GG0: 1.08%; GG4: 1.23%; GG8: 1.59%). In conclusion, high digesta viscosities in the guar gum fed fish may explain the observed reduced nutrient digestibilities and increases in digestive organ weights.  相似文献   
78.
Formulating swine diets containing fibrous coproducts based on net energy (NE) and standardized ileal digestible amino acid (SID AA) values is recommended for optimizing pig performance. However, the effects of applying this approach to diets with increasing dietary levels of wheat‐corn‐derived distillers dried grains with soluble (wcDDGS) on pig performance have not been evaluated. Thus, 48 pigs with an average body weight [BW] of 25.5 kg were used to determine the effects of increasing wcDDGS (1:1 wheat to corn ratio) content in grower diets on performance and apparent total tract digestibility (ATTD) of energy and nutrients. Pigs were housed in pens of either 2 barrows or gilts balanced for BW and fed 4 diets within sex for 42 days. Diets were a nutrient adequate corn–barley–soybean meal‐based diet with 0%, 10%, 20% and 30% wcDDGS, and were similar in calculated NE and SID AA values. Acid insoluble ash was used as the indigestible marker. Final BW and overall average daily gain (ADG) linearly decreased (p < 0.05) and feed efficiency tended to decrease (p = 0.07) with increased dietary wcDDGS. Overall average daily feed intake was not affected (p > 0.10) by dietary treatment. The ATTD of dry matter and energy linearly decreased (p < 0.01), whereas the ATTD of neutral detergent fibre linearly increased (p < 0.01) with increasing dietary level of wcDDGS. Increasing dietary wcDDGS content did not affect (p > 0.10) ATTD of Ca and P. In conclusion, increasing dietary wcDDGS content reduced growth performance and ATTD of energy in growing pigs. Thus, the risks of high dietary wcDGGS content may not be completely alleviated by formulating growing pig diets on the basis of NE and SID AA systems.  相似文献   
79.
We evaluated the effect of three sources of dried distillers' grains with solubles (DDGS) in diets of mid‐lactating dairy cows on milk production and milk composition and on digestibility in sheep. DDGS from wheat, corn and barley (DDGS1), wheat and corn (DDGS2) and wheat (DDGS3) were studied and compared with a rapeseed meal (RSM). RSM and DDGS were characterized through in situ crude protein (CP) degradability. Nutrient digestibility was determined in sheep. Twenty‐four multiparous cows were used in a 4 × 4 Latin square design with 28‐day periods. Treatments included total mixed rations containing as primary protein sources RSM (control), DDGS1 (D1), DDGS2 (D2) or DDGS3 (D3). RSM contained less rapidly degradable CP (fraction a), more potentially degradable CP (fraction b) and more rumen undegradable CP (UDP) than the three DDGS. In vivo digestibility of RSM organic matter was similar to DDGS. Calculated net energy for lactation (NEL) was lower for RSM (7.4 MJ/kg DM) than for DDGS, which averaged 7.7 MJ/kg DM. Cows' dry matter intake did not differ between diets (21.7 kg/day). Cows fed D1 yielded more milk than those fed D3 (31.7 vs. 30.4 kg/day); no differences were found between control and DDGS diets (31.3 vs. 31.1 kg/day). Energy‐corrected milk was similar among diets (31.2 kg/day). Diets affected neither milk fat concentration (4.0%) nor milk fat yield (1.24 kg/day). Milk protein yield of control (1.12 kg/day) was significantly higher than D3 (1.06 kg/day) but not different form D1 and D2 (1.08 kg/day each). Feeding DDGS significantly increased milk lactose concentration (4.91%) in relation to control (4.81%). DDGS can be a suitable feed in relation to RSM and can be fed up to 4 kg dry matter per day in rations of dairy cows in mid‐lactation. However, high variation of protein and energy values of DDGS should be considered when included in diets of dairy cows.  相似文献   
80.
The effect of supplementing leaves of four tannin‐rich plant species with polyethylene glycol 6000 (PEG) on nutrient intake and digestibility as well as on weight gain, feed conversion ratio (FCR) and N retention of zebu bulls (Bos indicus) was studied. Leaves of Albizia gummifera, Grewia ferruginea, Prunus africana and Syzygium guineense, containing, respectively, 85, 55, 76 and 172 g condensed tannins (CT) per kg dry matter (DM), were combined with natural pasture hay in a ratio of 40:60 on DM basis. The four diets were fed both without and with addition of PEG, at a dose of 40 g per kg DM, to eight zebu bulls during trials of 25 days in an 8 × 8 randomized crossover design. Supplementation with PEG increased nutrient intake, digestibility, FCR, N retention and average daily gain (p < 0.01). A diet × PEG interaction was observed for nutrient intake as well as for crude protein, neutral detergent fibre and acid detergent fibre digestibility (p < 0.05), but the effect size of PEG addition could not be attributed to the CT content as such, and also digestibility without PEG was not related to CT content of the diets. The reason why the efficacy of PEG addition did not relate to the CT content pointed the need to evaluate other factors that can help to predict the efficacy of PEG, for example, tannin type or interaction with other nutrients.  相似文献   
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