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1.
A study was conducted to evaluate the effects of ochratoxin A (OA) on Escherichia coli-challenged broiler chickens. Day-old broiler chicks were separated into two groups of 92 chicks each, with one group fed a control mash diet, and the other fed a mash diet containing 2 ppm OA. On day 14, each group was further separated into two groups, with one group inoculated with E. coli O78 (1 x 10(7) colony-forming units/0.5 ml), whereas the other group was not inoculated with E. coli. After E. coli inoculation on day 14, four birds from each group were euthanatized at 1, 2, 3, 5, 7, 10, 14, and 21 days postinoculation. Escherichia coli infection caused dullness, depression, huddling, and diarrhea. Mortality was 14.3% in chicks infected with E. coli but fed no OA. Mortality increased to 35.7% in chicks fed OA and infected with E. coli. Decreased body weight and reduced feed intake were observed in chicks fed OA, and the effects were more pronounced in chicks fed OA and infected with E. coli. Increased serum levels of aspartate aminotransferase, alanine aminotransferase, uric acid, and creatinine and decreased levels of total proteins, albumin, globulins, calcium, and phosphorus were observed in OA-fed birds. Escherichia coli infection did not cause significant alteration in any of the serum biochemical parameters. The presence of OA in poultry rations increased mortality and the severity of an E. coli infection.  相似文献   

2.
Broiler chicks were fed on a high energy, commercial‐type ration with 20 g oxycarotenoids/ton1 for 5 weeks. They were then transferred to two finisher rations: one with 20 g oxycarotenoids from the ingredients plus 3 g canthaxanthin/ton; the other containing 26 g oxycarotenoids/ton derived solely from the ingredients. Three replicated groups fed on each finisher ration were inoculated daily for 5 d with either 6000 sporulated oocysts of E. maxima, 30,000 sporulated oocysts of E. acervulina or no coccidial oocysts. The resultant mild infections caused reduced growth and impaired food conversion irrespective of the ration fed. Pigmentation, based on shank visual scores, plasma and toe‐web total carotenoid concentrations, was adversely affected in all infected groups. Groups fed canthaxanthin had higher visual scores than comparable groups not so supplemented; however, the presence of coccidiosis depressed flesh pigmentation proportionately in both groups judged by several pigmentation parameters. E. acervulina infection was as deleterious to the broiler as E. maxima, based on these criteria.  相似文献   

3.
Two experiments were conducted to evaluate the effect of feeding rations in the form of mash, pellets or ground pellets on the performance of the broiler chicken when the ration contained varying levels of fat.

When a low‐fat ration was fed, chicks consuming pellets or ground pellets gained more body weight, consumed more food and utilised food more efficiently than chicks fed mash. Concurrently, feeding of this ration as pellets or ground pellets increased the quantitative gain in carcass dry matter, fat and gross energy. These increases were accompanied by an improved efficiency of metabolisable energy utilisation. The response of chicks to feeding the low‐fat ration in the form of ground pellets indicates that the pelleting process per se caused a change in the ration constituents which improved efficiency of energy utilisation and increased weight gain. The observation that the performance of pellet‐fed chicks surpassed that of chicks fed ground pellets suggests that feeding pellets was inducing a response beyond that which could be attributed to the beneficial effects of the pelleting process per se. In general, increasing the fat level by 10 per cent of the ration decreased the chicks’ response to pelleting although, in the case of efficiency of energy utilisation, the beneficial influence of pelleting was still apparent.  相似文献   


4.
Chickens were fed a ration containing 30 per cent of toxic groundnut meal for up to six weeks. The concentration of aflatoxin (toxic metabolites of Aspergillus flavus) in the above ration was 3.06 p.p.m. At the end of 2nd, 4th or 6th week the birds were killed. The meat was removed from the bones and put through a meat grinder. The livers of three groups were pooled together. Three control groups of birds kept on commercial pellets were treated similarly.

Female ferrets, two years of age, were used in the present study. They were divided into four groups. The first three groups were given for one month meat from chickens fed the toxic ration for 2, 4, and 6 weeks, respectively. Each of these three groups contained one control ferret that was fed with the meat of chickens fed a commercial ration for a similar period of time. One half of the 4th group was fed pooled liver from intoxicated birds and one half was fed liver from control birds.

No significant changes in the ferret tissues were observed as a consequence of feeding them with the meat or liver from the chickens chronically poisoned with toxic groundnut meal.

  相似文献   

5.
A feeding trial was conducted on a total of 96 pigs to investigate the effect of lysine supplements added to rations of wheat+extracted soya bean meal and rations of wheat+extracted gound nut meal. Significant differences in the daily weight gains were noted (up to the 4th week of experiment) between the groups fed the soya bean meal ration and those fed the ground nut meal ration and between the soya bean meal groups receiving rations supplemented with 0,71% lysine or 0.79% lysine. At the termination of the trial (8th week) these differences were no longer significant statistically although the soya bean meal group fed rations supplemented with 0.79% lysine yielded clearly the best results.  相似文献   

6.
24 experimental birds were fed the same basal ration containing 74% high-protein wheat, 4% extracted soya bean meal, 7% extracted groundnut meal, 2% feed yeast, 1.75% dried green meal, 1.25% mixed vitamins and 10% of a mineral mixture. The birds were placed in 4 groups each comprising 6 hens. The first two groups received an optimum of lysine (0.68%) added to the ration. The rations for the two other groups contained 0.55% lysine. 6 birds of each group receiving either the lysinesupplemented or the unsupplemented rations were colostomated to investigate in which way the hydrolysed urine would affect the true amino acid digestibility. 8.3% of urinary N from the total amount of faecal N were precipitated as uranyl acetate in the faeces of hens fed the lysine-supplemented ration as compared with 7.3% urinary N in birds receiving the unsupplemented ration. The corresponding figures for non-precipitable faecal N were 8.9% and 8.2%. A comparison was made between the levels of amino acids excreted by colostomated and non-colostomated hens showing that 12.4% +/- 3% and 11.7% +/- 3% more amino acids (figures for the supplemented and unsupplemented rations) were excreted in the presence of urine. On the basis of these results the authors recommend that only colostomated hens should be used in digestibility and total metabolism trials.  相似文献   

7.
The aim of the study was to determine the effect of dietary supplementation of a probiotic and a synbiotic on the morphometric parameters of the small intestine of broiler chickens. The experiment was conducted on three hundred sixty, one‐day‐old female Ross 308 chicks, which were randomly selected from 20,000 birds and divided into three treatment groups (n = 120) with ten replicates per treatment. The control group (C) was fed a commercial diet, the probiotic group (PRO) was fed the same diet with an added 1% of the probiotic Lavipan® (Lactococcus lactis, Carnobacterium divergens, Lactobacillus casei, Lactobacillus plantarum and Saccharomyces cerevisiae), and the synbiotic group (SYN) was fed the commercial diet with an added synbiotic: 0.8% of the prebiotic RFO (extracted from lupin seeds) and 1% Lavipan®. According to the manufacturer's data, apart from the typical probiotic action,microorganisms contained in the preparation release anti‐bacterial substances (hydrogen peroxide and bacteriocins) and, therefore, are antagonistic towards pathogenic bacteria present in the gut of animals. Supplementation took place in the first seven days of rearing, and all birds had ad libitum access to water and feed during the 42 days of the experiment. On the last day, all birds were slaughtered and samples from three segments of the small intestine were taken. Villi area, height, width and crypt depth ratios were read using Multiscan software. Synbiotic supplementation increased the BWG of broilers from first to tenth day of rearing, compared to the control group. The PRO group had improved villi morphometric parameters of the duodenum. In the jejunum and ileum, both bioactive substances improved villus width and villus surface area. Crypts were deeper in the small intestine of birds supplemented with bioactive substances, which allows greater renewal of the villi. As expected, the intestinal morphometric parameters of broiler chickens benefited from bioactive substance supplementation.  相似文献   

8.
Broiler chicks were fed on a commercial‐type ration containing 20 g oxy‐carotenoids/ton for 5 weeks, half receiving 0.005% roxarsone. All birds were then fed on finisher rations containing a moderate (20 g/ton) to high level (40 g/ton) of oxycarotenoids from food ingredients alone and in combination with 2 and 4 g canthaxanthin/ton for 26 d. The birds given roxarsone in the starter ration also received 0.005% roxarsone in the finisher ration together with the above‐listed oxycarotenoid supplements. Roxarsone was withdrawn from the ration 5 d prior to termination of the study to simulate commercial requirements.

The continuous feeding of 0.005% roxarsone had no effect on weight gain, food conversion or pigmentation as assessed by visual shank scores, using the Roche Yolk Color Fan, and colorimetric assay of total carotenoid concentrations in plasma, toe‐web skin and shank skin. Shank visual scores reflected the increased levels of oxycarotenoids derived from food ingredients alone and the effect of supplemental canthaxanthin. These data show that canthaxanthin is an effective pigmenter adjuvant, when added at 2 to 4 g/ton to rations containing 20 to 40 g of oxy‐carotenoids/ton from food ingredient sources. Concurrent feeding of 0.005% roxarsone, while having no positive effect on pigmentation, had no adverse effect on the pigmenting properties of canthaxanthin.  相似文献   


9.
Four complete isonitrogenous (crude protein 13%) rations with 0 (T1), 5 (T2), 10 (T3) and 15 (T4) per cent calcium soap from red palm oil (protected fat) were formulated and evaluated using four Deccani lambs (19.32 ± 0.82 kg) in a completely randomized design at the end of a growth trial. The average daily dry matter intake (% body weight or g/kg W0.75 per day) in lambs fed ration T4 was significantly (p < 0.05) lower than in those fed rations T1, T2, and T3. There was no significant difference in the digestibility of proximate principles and cell-wall constituents except for ether extract (EE) and cellulose. EE digestibility was significantly (p < 0.05) higher by 15.71, 14.65 and 11.56 percentage units, respectively in lambs fed rations T2, T3 and T4 as compared to those fed ration T1. Ration T4 had significantly (p < 0.05) lower cellulose digestibility than rations T1, T2 and T3. Nitrogen and phosphorous balances (g/day) were not significantly (p > 0.05) different among the four rations. Calcium balance (g/day) was higher by 0.65, 1.39 and 1.40, respectively, in lambs fed rations T2 (p > 0.05) and T3 and T4 (p < 0.05) in comparison to those fed ration T1. Digestible crude protein and total digestible nutrients content (g/kg DM) of rations were not significantly (p > 0.05) different among the four rations. It is concluded that calcium soap from red palm oil can be supplemented up to 10% level as a concentrated energy source in the rations of Deccani lambs without any adverse effect on dry matter intake and cellulose digestibility.  相似文献   

10.
In the present paper regression techniques were used for determing the true digestibility of amino acids from lysine-supplemented rations fed to laying hens as compared with unsupplemented rations of the same composition. 5 groups of 4 hens each were investigated receiving graded amounts of food and nutrients. The daily amounts of pellets fed per bird in group 1 to 5 were 120 gms, 100 gms, 80 gms, 60 gms and 40 gms. The quantity of lysine contained in 100 gms of the pellets was 664 mg in ration 1 and 554 mg in ration 2, the corresponding N values being 2.57 gm and 2.62 mg. The total amount of endogenic amino acids excreted per day was 128 mg per kg of body weight in birds receiving the lysine-supplemented ration and 132 mg per kg of body weight for the lysine-deficient ration. Data for the true digestibility of lysine and isoleucine were significantly higher in the case of the lysine-supplemented ration than with the lysine-deficient mixture. Lysine values were 86% and 75%, the corresponding lysine data in crude faecal proteins 4.8% and 7.1%. Generally speaking, the crude faecal protein of hens fed the lysine-deficient diet contained higher proportions of most of the essential and non-essential amino acids.  相似文献   

11.
This study aimed to evaluate the effect of micronized pea seeds introduced into feed mixes for broilers on the slaughter yield, blood lipid parameters, content of fatty acids in selected tissues, and meat quality. The studies involved 150 1‐day‐old Ross 308 chicks split into three groups (for 42 days). The feed rations differed in terms of the source of proteins: in the control group (C), it was post‐extraction soybean meal (SBM) 100%; in group I, SBM 50% and micronized peas 50%; and in group II, micronized peas only, 100%. Irradiated pea seeds added to the feed ration for chicks reduced the fattening grade of carcasses (P < 0.05). Additionally, significant improvement of blood lipid indices was recorded. The share of the irradiated pea seeds in feed mixes decreased the share of saturated fatty acids in the muscles and abdominal fat and had a positive effect on the n‐6/n‐3 ratio, hypocholesterolemic / hypercholesterolemic ratio, as well as the atherogenic and thrombogenic indices (P < 0.05).  相似文献   

12.
This experiment was conducted to assess nutritional potential of corn steep liquor (CSL) as an alternative protein source in broiler's diet. A total of 280‐day‐old unsexed broiler chicks were randomly distributed into four experimental groups in a simple randomised experimental design (each group had seven replicates; 10 birds per each). Four iso‐nitrogenous and iso‐caloric broiler starter and finisher diets (C, LCSL, MCSL and HCSL) were formulated containing 0%, 5%, 10% and 15% CSL respectively. Results revealed that chicks fed MCSL diet had significantly (p ≤ .05) the heaviest Body weight, highest Body weight gain and the lowest feed conversion ratio followed by those fed HCSL diet. In the starter period, LCSL and MCSL diets resulted in better (p ≤ .05) dry matter (DM) (89.57%) and crude protein (67.67%) digestibilities respectively. In the finisher period, DM, crude fibre and fat digestibilities were not affected by CSL inclusion levels; while crude protein digestibility was significantly (p ≤ .05) high in the groups fed LCSL and HCSL diets. The CSL inclusion had no effect on blood haematology except serum uric acid, which tended to increase with increasing CSL levels. No microscopic changes were exhibited on liver, heart, kidneys and intestine of birds across all dietary treatments. However, crops in birds fed HCSL diet showed moderate to severe hypertrophy and hyperplasia of the mucosal lining. The study showed that CSL could be added up to 15% in broiler's diet without any adverse effect on bird's performance.  相似文献   

13.
The present study was conducted to evaluate the adverse effects of an interaction between low levels of dietary aflatoxins (AF) and Eimeria tenella infection on broiler chicks. A set of 1-day-old chicks were raised for 35 days in the following groups: a control group, a group fed AF, a group fed AF and inoculated with E. tenella (AF + E.ten), and a group inoculated with E. tenella alone. AF in the contaminated diet were given at 200 ppb starting from the seventh day after hatching while E. tenella was inoculated at a dose of 5 × 104 sporulated oocysts per chick at the 14th day after hatching. Worsened performance traits and high mortality were all observed in the treated birds, particularly the AF + E.ten group. Lesion scores and oocyst outputs were not different within groups. Chickens fed with AF had significantly increased serum ALT and ALP activities as well as decreased albumin content. They also showed hepatomegaly, hepatocytic vacuolation and necrosis, an atrophied bursa of Fabricius, and a thymus with tissue depletion. E. tenella-infected broilers displayed a significant reduction in packed cell volume, hemoglobin content and lymphocyte percentage, and showed hemorrhagic typhlitis. The deficits in hepatic function and hematologic parameters as well as the gross pathological, and histopathological changes, were more common and more severe in the group that was exposed to both aflatoxicosis and coccidiosis than in the groups exposed to either treatment alone. Thus, the combination of aflatoxicosis and E. tenella infection may influence the course of coccidial infection due to additive effects.  相似文献   

14.
This study was conducted to investigate the effect of spray‐dried porcine plasma (SDPP) in broiler chickens under Salmonella sofia disease challenge. The experiment comprised five starter diets: positive control (no supplement), diet supplemented with in‐feed antibiotics (IFA; salinomycin 0.05% + zinc bacitracin 0.033%) and diets supplemented with SDPP at 10 or 20 g/kg diet. All four of these groups were challenged with Ssofia, while a fifth group was unchallenged and used as the negative control. The experimental diets were fed to 14 days; then, the birds were switched to commercial‐type grower and finisher diets. Oral inoculation of the challenged groups with Ssofia occurred on day 8, 10 and 12. Body weight was significantly higher in the birds fed diets containing IFA and SDPP than in the challenged control group, but it was only significant in starter and grower phases. In general, there was an improvement in the weights of the immune‐related organs, but it was only significant for the weight of the bursa of SDPP‐fed birds at 13 days. At day 13, blood potassium content was lower and the concentrations of IgG and IgM tended to be lower in the birds fed on low‐SDPP starter diets than those of the other groups. There were significant differences in the concentration of lactic acid in the ileum and acetic acid, formic acid, butyric acid and propionic acid in the caeca. Inclusion of SDPP to the starter diets of broiler chicks had positive effects on broiler performance, immunity and gut health during exposure to highly pathogenic conditions.  相似文献   

15.
This study was conducted to evaluate the efficacy and safety of dietary urea in sheep rations having a 50:50 concentrate:roughage ratio. Sixty‐four Dorper × thin‐tailed Han crossbred ram lambs with an average body weight of 30.8 (±0.02) kg were randomly divided into four groups of 16 sheep each, and each group was fed one of the following diets: a basal diet (CON), or CON supplemented with 0.5% (0.5UTM), 1.5% (1.5UTM) or 2.5% (2.5UTM) urea. Growth performance, carcass characteristics, non‐carcass offals, meat quality and peptic tissue lesions were assayed. The average daily weight gains for CON, 0.5UTM, 1.5UTM and 2.5UTM were 216, 218, 200 and 170 g, respectively, with the CON and 0.5UTM groups higher than 2.5UTM group (p < 0.05). Sheep from the 2.5UTM treatment had a significantly lower dry matter intake (1.29 kg/day) than those from the CON and 0.5UTM treatments (1.42 and 1.43 kg/day, p < 0.05), and the feed conversion ratio in the 2.5UTM group was the highest (p < 0.05). Carcass characteristics, including shrunk body weight, empty body weight, hot carcass weight, dress percentage, and the absolute or relative weight (% body weight) of heart, liver, spleen, lung and kidney, were not altered by the treatments (p > 0.05). The muscular pH of 2.5UTM was higher than that of CON (5.68 vs. 5.52, p < 0.05), and shear force in 0.5UTM was lower compared with CON and 2.5UTM (p < 0.05). The anatomical structure lesions in kidneys became more serious with the increasing dietary urea concentrations, with the 2.5UTM animals showing the most severe lesions compared with CON animals. Therefore, supplementary urea as a non‐protein nitrogen source for sheep should not exceed 1.5% of ration having a 50:50 concentrate:roughage ratio to ensure efficacy and safety.  相似文献   

16.
A fattening trial was carried out with 8 groups of broilers each comprising 1225 birds. Within this trial tests were made to replace the protein feeds of newly hatched chicks over a period of up to 56 days of age, by wheat rich in crude protein. If wheat with a high crude protein content is fed supplementation with lysine and methionine will be necessary depending on the kind of protein feed used. No supplementation with amino acids is required if rations of fish meal + extracted soya bean meal are used despite their reduced content of these amino acids. The broilers consumed larger quantities of the wheat + extracted soya bean meal+fish meal ration than of the mixtures containing no fish meal. Food requirements per unit of weight gain were the same for the mixtures containing high-protein wheat and for the standard maize ration. The lowest food consumption per unit of weight gain was computed for the wheat + extracted soya bean meal diet supplemented with amino acids. The same quantities of lysine, thioamino acids and threonine were necessary for broilers receiving the wheat rations as for birds of the standard group. Protein feed may be saved by using high-protein wheat in the fattening of broilers. The rates of weight gain obtained with these rations are the same or even better than those achieved with rations of maize + fish meal+soya bean meal.  相似文献   

17.
不同水平甘露寡糖对肉鹑生长性能和血清胆固醇的影响   总被引:1,自引:0,他引:1  
为了探讨不同水平甘露寡糖对肉鹑生产性能和血清胆固醇的影响。将240只1日龄鹌鹑随机分成4组,每组设4个重复,每个重复15只鹌鹑,Ⅰ组为对照组,饲喂基础日粮,Ⅱ~Ⅳ组为试验组,在基础日粮中分别添加0.5%、1%、2%的甘露寡糖,进行为期50 d的饲养试验。结果表明,与对照组相比,Ⅲ、Ⅳ组的35日龄和50日龄的肉鹑的体重分别提高2.02%、2.66%,7.36%、7.90%。血清胆固醇含量:Ⅱ组35日龄肉鹑胆固醇含量比对照组升高22.22%,Ⅱ组50日龄肉鹑胆固醇含量比对照组降低12.20%;Ⅲ组35日龄肉鹑和50日龄肉鹑的胆固醇含量分别降低3.70%、9.76%,Ⅳ组35日龄肉鹑胆固醇含量比对照组升高7.41%,50日龄肉鹑的胆固醇含量降低21.95%。试验研究表明:在肉鹑生产中,适量添加甘露寡糖可增加肉鹑体重并且降低胆固醇含量。  相似文献   

18.
The present study was conducted to evaluate the chemical composition, intake and digestibility of crop residue based rations by Red Sokoto goats maintained on natural pastures and Digitaria smutsii hay during the dry season of the year. Twenty‐eight non‐lactating does were blocked for weight and assigned to 7 treatment groups comprising 4 does each in a completely randomized design. Ration A, the conventional concentrate ration, was used as the positive control, Rations B and C were the two crop residue based test rations, while Ration D, the unsupplemented treatment, was used as the negative control. Each of the supplementation rations was fed at 1% and 2% of the doe's body weight. Ration A had the highest crude protein percentage of 17.19% while Rations B and C had 9.54 and 10.38%, respectively. The naturally grazed pastures and Digitaria smutsii hay (Ration D) contained the least protein: 2.76 and 4.75%, respectively. Ration D also had the highest percentages of acid detergent fiber, neutral detergent fiber and lignin (49.14, 74.73 and 9.49% in hay and 50.29, 8.27 and 11.5% in grazed pastures, respectively). Ration A on the other hand, had the lowest percentages of acid detergent fiber (20.00%), neutral detergent fiber (40.01%) and lignin (4.64%). The results indicated that the supplemented group of does had significantly higher (P < 0.05) dry matter and crude protein intakes as well as nutrient digestibilities than the unsupplemented groups. A comparison of the unsupplemented animals with all the other treatment groups revealed that dry matter digestibility improved by a range of 4.1–27.9%, while crude protein digestibility improved by 17.1–42.2%, the highest value being in does on Ration A. It was concluded that goats were able to subsist and make appreciable gains in the long dry season on crop‐based diets that compared favorably with the conventional concentrate rations. Of the two tested crop residue based rations, Ration C is a better supplementation package than Ration B.  相似文献   

19.
An experiment was conducted to study the effect of roughage to the concentrate ratio of complete diets containing sweet sorghum bagasse (SSB), an agro-industrial by product, as sole roughage source on nutrient utilization in ram lambs. Twenty-four Nellore × Deccani cross ram lambs aged about 3?months (average body wt. 10.62?±?0.03?kg) were randomly allotted into four groups fed with CR-I (60R:40C), CR-II (50R:50C), CR-III (40R:60C), and CR-IV (30R:70C) complete diets. The roughage to concentrate ratio did not affect the dry matter intake (in grams/day or grams/kilogram weight(0.75)). The crude protein (P?相似文献   

20.
An experiment was conducted by feeding sorghum straw (Sorghum bicolor) based complete rations at roughage concentrate ratio 70:30 (CR-I), 60:40 (CR-II), 50:50 (CR-III), and 40:60 (CR-IV) for 180 days to find out suitable ratio of sorghum straw in the complete ration (mash form) on nutrient utilization and nitrogen balance in Nellore ram lambs. The DMI (g/day) increased significantly (P?<?0.05) as level of concentrate increased in complete rations. No significant difference was found in digestibilities of proximate nutrients. However, CP digestibility was higher either significantly or nonsignificantly by 2.12, 5.50, and 9.36 %, respectively, in lambs fed with CR-II (P?>?0.05), CR-III (P?>?0.05), and CR-IV (P?<?0.05) rations in comparison to lambs fed with CR-I ration. Furthermore, CP digestibility was higher by 7.09 and 3.66 % in lambs fed with CR-IV ration than those fed with CR-II (P?<?0.05) and CR-III (P?>?0.05) ration. The average CWC digestibility coefficients were comparable among four rations. The N intake (g/day) was significantly (P?<?0.01) different and progressively increased by 31.46, 48.69, and 82.86 % in ram lambs fed with CR-II, CR-III, and CR-IV rations, respectively, in comparison to CR-I ration. The N balance (g/day) was higher either significantly or nonsignificantly by 34.46 (P?>?0.05), 133.46 (P?<?0.01), and 198.87 % (P?<?0.01) with CR-II, CR-III, and CR-IV rations, respectively, in comparison to CR-I ration. Based on results, it is inferred that the level of sorghum straw in complete ration had no effect on digestibility of nutrients barring crude protein in Nellore ram lambs.  相似文献   

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