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1.
The availability of wood by-products for bedding material is falling in many regions due to rising demand for other uses. The objective of this study was to evaluate six alternative litter sources—river bed sand, coconut husk, rice hulls, Guinea grass, newspaper, and corncob—as a substitute for wood shavings (WS). The trial was carried out over 35 days in an open-sided and naturally ventilated broiler house under conditions of high ambient temperatures and relative humidity. During the brooding period (0 to 14 days), chicks raised on grass had lower (P?<?0.05) footpad temperature than those grown on WS. After the brooding period (15 to 35 days), the temperatures of both litter and birds were higher (P?<?0.05) for coconut husk than for WS. Grass litter resulted in lower (P?<?0.05) final BW, FCR, and production efficiency. Sand and rice hulls were associated with lower (P?<?0.05) survival rate and higher (P?<?0.05) gizzard weight. Litter type did not affect carcass and meat yields. The footpad dermatitis score, associating incidence and severity, was not statistically different among the litter substrates tested, although numerically higher in coconut husk, grass, and corncob. The results obtained in this experiment indicate that, in a hot and humid environment, all materials except grass can be used as a substitute for wood shavings with comparable production efficiency.  相似文献   

2.
Forty-eight crossbred Landrace?×?Large white pigs with an average body weight of 8.5?±?0.4 kg and aged 2 months were used to evaluate performance and carcass characteristics of pigs fed two diets in which bran from maize or wheat was used as the energy source. A third diet based on whole maize grain was used as a control. Animals in groups of four, balanced for litter, sex and weight were allotted to dietary treatments in a completely randomised design with four replications. Data were collected on feed intake and weight gain for a period of 4 months. A digestibility trial was carried at the end of the feeding trial using two male pigs per treatment while six pigs per treatment were randomly selected for slaughter to determine carcass characteristics. Daily gain averaged 0.23, 0.31 and 0.13 kg/day, for pigs fed maize bran, wheat bran and whole maize diets, respectively. Average feed intake and final body weight were significantly (P?<?0.05) affected by diets. Digestibility of dry matter, crude fibre and calcium were higher (P?<?0.05) for pigs fed maize bran while crude protein digestibility was highest (P?<?0.05) for the pigs fed wheat bran. There were significant differences (P?<?0.05) between the diets in carcass yield, ham, head, trotters and heart weights and also for rib weight, rib eye muscle and other tissues. This study indicates that comparable performance of growing pigs fed cereal bran and full-grain diets are real.  相似文献   

3.
The experiment was conducted to determine feed intake, digestibility, body weight change, carcass characteristics, and sensory quality of meat of Menz sheep supplemented with a concentrate mix and combinations of different proportions of tossign (Thymus serrulatus). Twenty yearling intact male Menz sheep were divided according to their initial body weight into five blocks of four animals in a randomized block design, and treatments were assigned randomly to each sheep within each block. The treatments were a basal diet of hay alone (T1) and supplemented with 300 g concentrate mix (T2), 200 g concentrate mix?+?100 g tossign (T3), and 100 g concentrate mix?+?200 g tossign (T4) on a dry matter basis. The results indicated that supplementation of tossign together with concentrate mix significantly increased (P?<?0.001) feed intake and improved DM and nutrient digestibility compared to the non-supplemented group. Supplementation of tossign with concentrate significantly improved (P?<?0.001) daily weight gain, feed conversion efficiency, and carcass characteristics of sheep compared to the non-supplemented group. Flavor and aroma scores of meat samples of sheep in T3 and T4 were significantly higher (P?<?0.001) than the corresponding values in T1 and T2. The scores for tenderness, juiciness, and degree of marbling of meat samples of sheep were significantly higher (P?<?0.001) in T3 and T4 compared to meat samples of sheep in T1. Inclusion of small amounts of tossign as additive in concentrate mix supplementation can improve the sensory quality of meat of Menz sheep.  相似文献   

4.
A 49-day feeding trial was conducted to determine the effect of Siam weed leaf meal (SWLM)-based diets on growth, organ, and carcass weight characteristics and economics of production of broilers. Proximate biochemical composition of SWLM and the appropriate inclusion level of SWLM for optimum productivity were also determined. Ninety-six-day-old Chi broiler chicks were randomly divided into 4 groups of 24 birds, and each group replicated three times. Each group was assigned to one experimental diet in a completely randomized design marked T1 (0%), T2 (4%), T3 (8%), and T4 (12%). Proximate biochemical results revealed that SWLM is rich in protein (20.52%) and minerals (9.29%). Birds on diets T1 and T2 had similar (p >?0.05) final live weights (FLW), which were higher (p <?0.05) than those on diets T3 and T4. Birds on diet T2 had the highest (p?<?0.05) daily feed intake (DFI) and daily weight gain (DWG), while birds on diet T1 had the best feed conversion ratio (FCR) followed by birds on diet T2. The result of quadratic model regression analyses showed that SWLM levels of 1.48, 1.50, 1.47, and 1.56% supported optimum final live weight, DFI, DWG, and FCR. There were no significant (p >?0.05) differences in the dressing percentage, but there were significant differences in the carcass weight between birds on diet T4 and the other three diets. Similarly, pancreas and spleen had similar (p?>?0.05) weights across the treatments. There was significant difference (p?<?0.05) between birds on diets T1 and T4 in gizzard weight. Cost-benefit ratio was influenced (p?<?0.05) with T4 birds having better income of US$1 per US$10.18 invested. It is concluded that SWLM is rich in essential nutrients and therefore suitable for inclusion in broiler diets at level not beyond 2% for best final live weight, daily weight gain, and thigh weight.  相似文献   

5.
The objective of this study was to evaluate the effect of inclusion of dehydrated cassava starch residue (DCSR) on the performance, gastrointestinal tract characteristics and carcass traits of ISA Label JA57 slow-growing broilers. A total of 510 broilers at 21 were distributed in a randomized experimental design with 5 treatments (2, 4, 6, 8, and 10 % DCSR inclusion) and a control group, 5 replicates, and 17 birds per experimental unit. The DCSR inclusion from 21 to 49 days of age negatively influenced (P?P?>?0.05) feed conversion in the broilers with increasing of DCSR inclusion. From 21 to 79 days, DCSR inclusion impaired (P?P?P?P?>?0.05) the other parameters of carcass quality and yield, cuts, and percentage of abdominal fat. In conclusion, DCSR inclusion levels above 2 % compromised broiler performance.  相似文献   

6.
Different roughage-to-concentrate ratios of sweet sorghum bagasse (SSB) (a by-product of the biofuel industry)-based complete diets were assessed. Twenty four growing Nellore × Deccani ram lambs aged about 3 months (average body wt., 10.62?±?0.25 kg) were randomly allotted to four complete rations (CR) varying in roughage-to-concentrate ratios viz. 60:40 (CR-I), 50:50 (CR-II), 40:60 (CR-III) and 30:70(CR-IV) for a period of 180 days. The feed intake was comparable among the lambs fed different experimental complete diets. Average daily weight gain (in grams) was 77.31?±?4.90, 81.76?±?5.16, 85.83?±?2.83 and 86.30?±?3.25, and feed conversion ratio (in kilograms of feed per kilogram gain) averaged 11.42?±?0.68, 10.57?±?0.64, 10.17?±?0.37 and 9.96?±?0.38 in ram lambs fed CR-I, CR-II, CR-III and CR-IV rations, respectively. Statistically, differences in daily weight gain and feed conversion ratio among the lambs fed four experimental rations were not significant (P?>?0.05). The cost per kilogram gain was significantly (P?<?0.01) higher in ram lambs fed CR-IV and CR-III rations compared to CR-I ration, and it was comparable between CR-I and CR-II rations. Dressing percentage averaged 44.90?±?0.15, 42.57?±?0.72, 43.67?±?0.16 and 44.42?±?0.76 for the respective diets. No significant difference and trend was observed in preslaughter weight, empty body weight, carcass weights, dressing percentage, wholesale cuts and edible and non-edible portions of experimental animals. Similarly, no significant variation could be seen in bone and meat yield (in per cent) and their ratios in various wholesale cuts among the dietary treatments. The roughage-to-concentrate ratio did not affect the chemical composition of meat; however, the fat content of meat was linearly increased with increase in the proportion of concentrate in the diets. The results of the experiment indicated that SSB can be included at 60 % level in the complete diet for economical mutton production from growing Nellore × Deccani ram lambs.  相似文献   

7.
Lippia javanica leaves may have nutraceutical bioactivity and thus could be a viable alternative to antibiotic growth promoters in poultry diets. To test this hypothesis, a feeding trial was carried out to determine the effects of dietary inclusion of Lippia javanica leaf meal (LJ) on growth performance, blood parameters, carcass characteristics and meat quality of indigenous Potchefstroom Koekoek (PK) chickens. The leaf meal was used to dilute a commercial chicken grower diet at a rate of 25 or 50 g/kg diet. Two additional experimental diets, a positive control (commercial chicken grower diet with antibiotics, CON+) and a negative control (commercial chicken grower diet without antibiotics, CON–), were also formulated. Feed intake and growth performance were measured over a period of 13 weeks before slaughtering for carcass and meat quality measurements. Blood was collected in week 11 to determine haematological and serum biochemical parameters. Diet had no effect on overall FCE but significantly (P?<?0.05) affected bilirubin, alanine aminotransferase (ALT), aspartate transaminase (AST), sodium, potassium, cholesterol and magnesium levels in blood. When included at 50 g/kg, LJ increased carcass weight (P?<?0.05). Meat from CON– (6.07) and LJ50 (6.08) chickens had a higher pH than from CON+ (5.9) and LJ25 (5.8) chickens. Breast muscle in CON– chickens had higher (P?<?0.05) lightness (L*) value (53.2) compared to chickens fed on other diets. It was observed that meat from LJ25 chickens had the highest for redness value (2.3). It was concluded that L. javanica leaf meal can be included up to 50 g/kg in Potchefstroom koekoek chicken diets without causing negative effects on the birds’ feed intake, utilisation and weight gain. Diet-induced changes observed in blood parameters and meat quality fell within the expected normal ranges for indigenous chickens.  相似文献   

8.
To study the effect of increasing levels of wheat pollard as a replacement for wheat bran on growth and carcass characteristics of growing pigs, 64 crossbred (Landrace?×?Large white Yorkshire) pigs were fed with diets in which wheat pollard was added back to wheat bran in ratios of 15, 30, 45 and 60 %. The pigs were divided into groups of four, balanced for sex, ancestry and body weight. They were then allotted to the dietary treatments in a completely randomised design with four replications. The trial lasted 4 months and data were collected on feed intake and weight gain. A digestibility trial was carried out on eight male pigs per treatment during the growth period. At the end of the growth period, two pigs per replicate in each treatment (n?=?32) were slaughtered for determination of carcass characteristics. There were significant differences in the rate of gain and efficiency of feed utilisation among treatments. Diet significantly affected weights of the liver, lungs and small intestine (P?<?0.05). The availability of nutrients was not a limiting factor for the growing pigs and that substituting wheat bran by wheat pollard at 60 % improved the pig’s average daily gain and feed efficiency.  相似文献   

9.
1. This study was conducted to examine the effect of different levels of humic substances (HS) administered in drinking water on caecal microflora and mineral composition and colour characteristics of breast and thigh meats and the growth performance, carcass and gastrointestinal tract (GIT) traits of broiler chicks.

2. A total of 480 3-d-old broiler chickens were randomly allocated to 4 treatments with 4 cages per treatment and 30 bird (15 males and 15 females) chicks per cage. All birds were fed on commercial basal diet. The control birds (HS0) received drinking water with no additions, whereas birds in the other treatment groups received a drinking water with 7.5 (HS7.5), 15.0 (HS15.0) and 22.5 (HS22.5) g/kg HS. Mush feed were provided on an ad libitum basis. Body weight and feed intake of broilers were determined at d 0, 21, and 42, and feed conversion ratio was calculated. On d 42, 4 broilers (2 males and 2 females) from each cage were slaughtered and the breast and thigh meats were collected for mineral composition and quality measurements.

3. Performance, carcass and GIT traits and caecal microbial population of broiler chicks at d 42 were not affected by the dietary treatments. The lightness (L*) of breast and thigh meat decreased in broilers supplemented with 15 and 22.5 g/kg HS in drinking water. Although the redness (a*) of breast meat increased, yellowness of thigh meat decreased in broilers supplemented with 15 and 22.5 g/kg HS in drinking water (P < 0.05).

4. In conclusion, the 15 and 22.5 g/kg HS administration in drinking water can be applied for broiler chicks to maintain growth performance and improve meat quality without changing caecal microflora.  相似文献   


10.
通过营养调控改善鸡肉品质与风味。选100 d宣城黄鸡600只随机分为5组,分别饲喂优化日粮(OD)、OD+风味改良剂(MD)、MD+茶粉与甲壳质混合物、MD+昆虫蛋白硒,对照组饲喂原场饲粮。试验期55 d。结果表明:(1)试1、2、3、4组较对照组试鸡腹脂率分别降低45.28%,44.67%,64.04%,14.65%,其中试1、2组试鸡较对照组腹脂率显著降低(P〈0.05),试3组降低极显著(P〈0.01);试3组肝重率显著降低33.59%(P〈0.05);试2组腺肌胃率显著提高45.11%(P〈0.01)。(2)肌间脂肪1、3、4组较对照组降低,但试2组提高15.66%(P〈0.05);肌苷酸试1组较对照组低,试2、3、4组分别高17.48%(P〈0.05),9.35%,10.16%;试4组胸肌硒含量较试2组提高了163%(P〈0.01)。(3)鸡肉弹性试1、2、3组较对照组分别高7.32%,7.89%(P〈0.05),9.21%,而试4组则低2.63%;粘聚性试1、2与3组较对照组分别高2.78%,5.71%(P〈0.05),4.29%,试4组则低1.43%。日粮补饲茶粉与甲壳素混合物可显著降低腹脂沉积,有防止肌肉脂肪氧化,降低MDA水平,维持高pH值趋势;配制的风味改良剂也可显著降低腹脂率,并有提高肌苷酸、羟脯氨酸含量与肌内脂水平趋势,能显著提高肌肉弹性与粘聚性;昆虫硒可显著提高鸡肉中硒沉积量。  相似文献   

11.
The effect of replacing soybean crude protein (CP) with legume leaf meal (LLM) CP on feed intake, growth performance and carcass traits was studied in native female Moo Lath Lao pigs. The diets comprised one traditional diet (T) without soybean meal, one control diet (C) with soybean meal and six diets iso-nitrogenous with diet C in which soybean protein was replaced (33, 66 and 100 % of CP) with LLM CP from porcupine joint vetch (PLM) or Stylosanthes (SLM). Feed and water were offered ad libitum. Replacing soybean CP with LLM CP reduced (P?<?0.05) intake of dry matter (DMI), CP (CPI), metabolisable energy (MEI), final body weight (BW) and average daily gain (ADG), but had no effect (P?>?0.05) on feed conversion ratio (FCR). Increasing the replacement rate of soybean CP with LLM CP had a negative linear effect (P?<?0.001) on DMI, CPI, MEI, final BW and ADG, and on all carcass traits except lean meat percentage. There were no differences in dressing percentage or organ weight and length between treatments. Supplementing diet T with soybean meal resulted in higher (P?<?0.05) DMI, CPI and MEI, lower (P?<?0.05) FCR, and higher (P?<?0.05) final BW and ADG. Slaughter weight, hot carcass weight, eye muscle thickness, back fat, fat in carcass and lean meat were lower (P?<?0.05) with diet T than diet C. In conclusion, LLM from stylo and porcupine joint vetch can be used as a CP source to partially replace soybean meal CP in the diet of growing native female Moo Lath Lao pigs.  相似文献   

12.
ABSTRACT

1. Although fattening dual-purpose types or male layer hybrid chickens appears more ethical than the common practice of culling day-old male layer chicks, the lower feed efficiency of these birds raises concerns. Replacing feed ingredients that compete with food production by those of lower value for human nutrition would be beneficial.

2. Lohmann Dual (LD), a modern dual-purpose type, Lohmann Brown (LB), a male layer hybrid, and Hubbard JA 957 (HU), a slow-growing broiler type, were fattened for nine weeks on two diets (control or ?20% crude protein; n = 6 × 12 birds). Growth, carcass and meat quality were analysed.

3. Growth performance of HU exceeded that of LD and especially of LB. The growth depression caused by the low-protein diet fed to LD (?7%) was only half of that found in HU (?13%). The LD fed the control diet had the same feed efficiency as the HU fed the low-protein diet. Even the LB had a lower performance and feed efficiency with the low-protein diet in growth. There was a gradient in carcass properties (weight, dressing percentage, breast meat yield, breast proportion and breast angle) from HU to LD to LB, with some additional adverse effects of the low-protein diet especially in HU. There were some breed differences in fatty acid profile in the intramuscular fat.

4. In conclusion, the dual-purpose type used complied with regulations for Swiss organic poultry systems in terms of growth rate and was found to respond less when fed a low-protein diet than the slow-growing broiler type. The LB males were inferior in all growth and carcass quality traits. Future studies need to determine the exact protein and amino acid requirements of dual-purpose and layer hybrid chickens and the economic feasibility of the systems, especially for organic farming.  相似文献   

13.
Improvement in body condition was assessed in 40 cull ewes (>6 years), equally distributed in two groups and realimented with ad libitum roughage (gram straw) and two levels of concentrate feeding, i.e., 2.5 % (T1) of live weight (LW) and ad libitum (T2). Five representative animals from an initial 45 were slaughtered at the initiation of the study (0 day) and five animals from each treatment at 44, 67, and 90 days of experiment for carcass attributes. Improvement in body condition score (BCS), nutrient utilization, feed efficiency, and carcass traits were assessed at 44, 67, and 90 days. Metabolism trial of 6-day collection of feed, feces, and urine samples was conducted on five representative ewes from each group after 60 days of feeding. The level of concentrate feeding on LW gain and BCS was significant, and the duration of realimentation showed a linear improvement (P?<?0.001). The digestibility and intake of dry matter, organic matter, and crude protein was higher (P?<?0.05) in T2. The N intake, absorption, and balance showed a similar trend. Increase (P?<?0.05) in total N, trichloroacetic acid precipitable N, and ammonia N was observed with extension of realimentation period. Blood metabolic profile also showed improvement (P?<?0.05) from an undernourished state to normal after alimentation. Animals in T2 accumulated higher LW with minimal expenditure of metabolizable energy (73.4 vs 79.1 MJ) and higher efficiency of feed conversion during 68 to 90 days of realimentation. Linear improvement (P?<?0.01) in carcass traits (preslaughter weight, empty live weight, hot carcass weight, dressing percentage, and amount of subcutaneous and intramuscular fat) and composition of longissimus dorsi muscle was observed. Ad lib concentrate supplementation for a period of 90 days may thus be considered appropriate for achieving desired efficiency of gain and improvement in body condition of cull ewes for quality mutton production.  相似文献   

14.
The effect of feeding cassava root meal on growth performance, hydrocyanide intake, haematological indices and serum thiocyanate concentration of broiler chicks was investigated using 300-day-old male broilers. There were five dietary treatments arranged in a 2?×?2?+?1 factorial arrangement of two processing methods of cassava root (peeled and unpeeled) included at two levels (100 and 200 g/kg) plus a control diet (maize-based diet, containing no cassava root). Each treatment was replicated six times with ten birds per replicate. The feeding trial lasted for 28 days. Control-fed birds had the highest overall (P?P?P?P?P?P?P?P?P?P?P?P?P?P?相似文献   

15.
A 2?×?3 factorial experiment was carried out to evaluate the effect of goat genotypes and different concentrate levels on growth and slaughter characteristics of Small East African × Norwegian crossbred (SEA × N) and Small East African (SEA) goats. The three concentrate levels were T0 (no access to concentrate), T66 (66 % access to ad libitum concentrate allowance) and T100 (100 % access to ad libitum concentrate allowance). Twenty-four castrated goats of each genotype (18 months old with an average weight of 16.7?±?0.54 kg) were randomly allotted into T0, T66 and T100 treatments. Daily feed intake and fortnight body weight measurements were recorded for the whole 84-day experimental period, after which the animals were slaughtered. Feed intake of T100 animals was 536 g/day, which was 183 g/day higher than that of the T66 group. Supplemented goats (T66 and T100) had significantly (P?<?0.05) higher daily gain and body condition score, and better feed conversion efficiency and dressing percentage than T0 goats. The SEA goats had higher (P?<?0.05) hot carcass weight (8.2 vs. 7.9 kg) and showed better (P?<?0.05) dressing percentage than SEA × N animals. Among supplemented goats, the cost of a 1-kg gain under T66 was Tshs 213/= cheaper than T100 (US$1?≈?Tshs 1,500). It is concluded that goats should be grazed and supplemented with 353 g concentrate/day for satisfactory fattening performance and higher economic return on investment.  相似文献   

16.
Performance and meat quality characteristics of broilers fed fermented mixture of grated cassava roots and palm kernel cake (FCP-mix) as a replacement for maize were studied. One hundred and eighty (180), 7-day-old broiler chickens were divided into six groups of 30 birds, and each group replicated thrice. Six experimental diets were formulated for both starter and finisher stages with diets 1 and 6 as controls. Diet 1 contained maize whereas diet 6 contained a 1:1 mixture of cassava root meal (CRM) and palm kernel cake (PKC). In diets 2, 3, 4, and 5, the FCP-mix replaced maize at the rate of 25, 50, 75, and 100%, respectively. Each group was assigned to one experimental diet in a completely randomized design. The proximate compositions of the diets were evaluated. Live weight, feed intake, feed conversion ratio (FCR), carcass weight, and sensory attributes of the meats were obtained from each replicate and data obtained was analyzed statistically. The results showed that live weight, average daily weight gain (ADWG), average daily feed intake (ADFI), and FCR of birds on treatment diets were better than those on the control diets (Diets 1 and 6). The feed cost per kilogram weight gained decreased with inclusion levels of FCP-mix. Birds on diet 1 recorded significantly (p < 0.05) higher dressing percentage than those on the other five treatments. The sensory attributes of the chicken meats were not significantly (p > 0.05) affected by the inclusion of FCP-mix in the diets. FCP-mix is a suitable substitute for maize in broiler diet at a replacement level of up to 100% for best live weight, carcass weight yield, and meat quality.  相似文献   

17.
The objective of the study was to determine growth performance, viscera organ development, economic benefit and sensory characteristics of meat from broilers finished on Acacia anguistissima leaf meal-based diets. One hundred and eighty Cobb 500-day-old chicks were used in the study. Acacia anguistissima was used as a protein source and included in broiler diets at 0, 50 and 100 g/kg. Total feed intake (TFI), average daily gain (ADG), and gain to feed ratio (G:F) and cost benefit analysis were determined. There were no differences in TFI of broilers across treatments diets. Average daily gain and gain to feed (G:F) ratio were low (P?<?0.05) for broilers feeding on diet with100 g/kg acacia meal. Highest returns from weight gain were obtained from broiler chickens fed on diet with 50 g/kg inclusion level of A. anguistissima (P?<?0.05). Intestinal length increased with inclusion level of A. anguistissima whereas liver and spleen weight decreased with inclusion level of A. anguistissima (P?<?0.05). Female consumers gave higher scores for overall flavour intensity than male consumers (P?<?0.05). Treatment diets influenced consumer sensory characteristics of broiler meat (P?<?0.05). High sensory scores were observed for overall flavour intensity (OFI) for both boiled and deep fried meat from broilers fed 100 g/kg A. anguistissima. It can be concluded that A. anguistissima meal can be used effectively up to 50 g/kg in broiler diets without compromising performance of chickens and can influence a few sensory characteristics.  相似文献   

18.
This study was designed to evaluate the effects of dietary inclusion of zinc‐methionine (ZnMet) as a replacement for conventional inorganic zinc sources on performance, tissue zinc accumulation and some plasma indices in broiler chicks. A total of 450‐day‐old Ross male broiler chicks were randomly assigned to five pen replicates of nine experimental diets. Dietary treatments consisted of two basal diets supplemented with 40 mg/kg added Zn as feed‐grade Zn sulphate or Zn oxide in which, Zn was replaced with that supplied from ZnMet complex by 25, 50, 75 or 100%. At 42 days of age, three randomly selected birds from each pen were bled to measure plasma metabolites; then, the chicks were slaughtered to evaluate carcass characteristics. Results showed that dietary treatments affected (p < 0.05) feed intake during the starter period, and chicks on Zn oxide diets consumed more feed than sulphate counterparts. Furthermore, dietary substitution of inorganic Zn sources by ZnMet caused improvements (p < 0.01) in body weight gain during all experimental periods. Dietary supplementation of ZnMet improved feed conversion efficiency during 1–21 and 1–42, but not in 21–42 days of age. Complete replacement of inorganic Zn by that supplied from ZnMet caused an increase (p < 0.05) in relative liver weight. Similarly, dietary inclusion of ZnMet increased breast meat and carcass yields and reduced abdominal fat percentage (p < 0.05). Incremental levels of ZnMet increased (p < 0.05) zinc concentrations in liver and thymus, and the highest zinc accumulations were seen in 100% ZnMet‐supplemented birds. Interestingly, introduction of ZnMet into the diets partially in place of inorganic sources resulted in decreases (p < 0.01) in plasma uric acid and triglycerides concentrations. The present findings indicated that dietary ZnMet inclusion in replacement of inorganic sources in addition to improving growth performance, reduced plasma uric acid and triglycerides concentrations, consequently decreased abdominal fat pad and increased carcass meat yield.  相似文献   

19.
A 4?×?3 factorial experiment was carried out to evaluate the effects of age at entry to feedlot (AEF) and levels of concentrate feeding (LCF) on body weight gain, feed utilization and killing out characteristics of Tanzanian long-fat-tailed castrate sheep. The AEF points were 9, 12, 15 and 18 months, designated as AEF9, AEF12, AEF15 and AEF18, and the LCF were 50, 75 and 100 % of ad libitum concentrate intake designated as LCF50, LCF75 and LCF100, the last representing ad libitum concentrate intake with 10 % refusal rate. Grass hay as basal diet was offered ad libitum to each sheep. Daily feed intake and weekly live weight were recorded for a period of 84 days. Animals were slaughtered and carcass and non-carcass parameters were recorded. Dry matter intake (DMI) of hay decreased while DMI of concentrate increased (p?<?0.01) with increasing LCF. Daily gain in high level (LCF100) was 93.1 g/day, almost twofold higher than that in low level (LCF50) of feeding (39 g/day). Overall dressing percentage ranged from 40.7 to 46.5 % and increased with increasing AEF. The proportion of carcass bone decreased (p?<?0.05) with increasing AEF while that of fat increased (p?<?0.05) with increasing LCF. Age at entry × level of concentrate feeding interaction was detected for DMI, feed conversion ratio (FCR), slaughter body weight (SBW), muscle/bone ratio and bone (as % cold carcass weight (CCW)), but the effect was not regular. Entering fattening at 18th month seems too late, hence to get in the shortest time the highest output slaughter and carcass weights, fattening should start latest at 15 month.  相似文献   

20.
In a completely randomized block design with 96 Cobb-500 broilers, a study was conducted to evaluate the potential of dietary inclusion of sprouted then roasted guar bean in broiler diets. The 96 male day-old broiler chicks, blocked by pen into equal weight groups of six chicks replicated four times per treatment, were randomly allocated to treatment diets containing graded levels of sprouted then roasted guar bean meal (GBM) at 0, 50, 100 and 150 g kg?1 inclusion level. The guar bean was sprouted and roasted to reduce guar gum effect. Total feed intake decreased significantly as the guar bean meal content increased in the starter phase (P < 0.05), but no significant differences in intake of the finisher phase (P > 0.05) were observed. Diets containing 0 and 50 g kg?1 GBM recorded significantly higher total feed intake compared to the diet containing 150 g kg?1 GBM. Although average weight gain was not significantly different in birds fed 0 and 50 g kg?1 GBM diets, it was significantly higher than in birds fed on 100 and 150 g kg?1 GBM diets. Feed conversion ratio was not significantly different among treatment groups (P > 0.05) but showed a general decreasing trend with increasing guar bean meal inclusion level, the effect being more pronounced during the starter phase. In conclusion, the optimum inclusion level of sprouted then roasted guar bean meal in broiler diets is 50 g kg?1.  相似文献   

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