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71.
Felipe A Nascimento Naiara C Silva Laura F Prados Rodrigo D L Pacheco Bradley J Johnson Bruno I Cappellozza Flvio D Resende Gustavo R Siqueira 《Journal of animal science》2020,98(12)
We hypothesized that the inclusion of calcium salts of fatty acid (CSFA) into the diets and the fatty acid (FA) profile of the supplements would impact performance and meat characteristics of Bos indicus bulls. Hence, the objective was to evaluate the effects of CSFA profiles on intake, body weight (BW), carcass, and meat characteristics of feedlot-finished B indicus bulls. Fifty-three Nellore bulls [initial BW 315 ± 5.9 kg and 20 ± 2 mo] were used. At the beginning, 6 bulls were randomly chosen and slaughtered for determination of their BW composition, and the remaining 47 bulls were evaluated during a 140-d experimental period. The bulls were placed in individual pens, blocked according to initial BW and randomly allocated to 1 of the 3 following treatments: (1) control diet containing sugarcane bagasse, ground corn, citrus pulp, peanut meal, and mineral–vitamin mix (CON), (2) CON with the addition of 3.3% of CSFA from soybean oil (CSO), or (3) CON with the addition of a mixture of 3.3% of CSFA from palm, soybean, and cottonseed oils (CPSCO). Diets were offered ad libitum and formulated to be isonitrogenous. Bulls supplemented with CSFA had a greater (P < 0.01) final BW, dry matter intake, average daily gain (ADG), feed efficiency (FE), and FA intake vs. CON. Among carcass parameters, CSFA-supplemented bulls had greater (P < 0.01) carcass ether extract concentration vs. CON bulls. When the CSFA profile was evaluated (CSO vs. CPSCO), CPSCO bulls had a better (P ≤ 0.03) FE, carcass ADG, and hot carcass weight (HCW) vs. CSO bulls. The FA intakes differed among CSFA treatments, as the total saturated, palmitic, and oleic FA intakes were greater for CPSCO (P < 0.01), whereas lower intakes of total unsaturated and polyunsaturated FA (P < 0.01) were observed for CPSCO vs. CSO. Samples from the Longissimus muscle contained greater palmitoleic (P = 0.01) and reduced linoleic (P = 0.02) FA concentrations in CSFA-supplemented bulls vs. CON bulls. In agreement with the FA intakes, CPSCO-supplemented bulls had a greater (P ≤ 0.05) unsaturated FA concentration vs. CSO in Longissimus muscle. In summary, CSFA supplementation improved the performance of finishing B. indicus bulls vs. CON. Moreover, the inclusion of CSFA from palm, soybean, and cottonseed oil benefited the FE, carcass ADG, and HCW compared with the inclusion of CSFA from soybean oil, demonstrating the potential of specific FA for improving the performance and meat quality of B. indicus bulls. 相似文献
72.
S. N. Qaisrani M. W. A. Verstegen W. H. Hendriks R. P. Kwakkel 《British poultry science》2020,61(1):43-50
ABSTRACT1. This study determined the effects of three protein sources (PS), each at two digestibility crude protein (DCP) levels, on performance, gut morphology and fermentation characteristics in the hindgut of broilers.2. It was hypothesised that broilers fed ingredients high in indigestible CP, i.e. rapeseed meal (RSM) or maize gluten (MG), could potentially cause reduced growth, impaired gut health, and more protein fermentation products in caecal digesta. Increasing the DCP level in each of the indigestible CP diets may compensate for these detrimental effects.3. In total, 288 one-d-old male Ross 308 broilers were used in a completely randomised 3 × 2 factorial design, with six replicate pens per treatment. Three PS: soybean meal (SBM), rapeseed meal (RSM) or maize gluten (MG), and two DCP levels: 15.8 and 17.2% were used.4. Broilers fed SBM had increased feed intake and BWG and improved FCR compared with those fed RSM and MG diets. Broilers fed high DCP had better performance compared with those on low DCP. No significant effects of PS or DCP level were found on gastrointestinal tract development, caecal ammonia or volatile fatty acid concentrations.5. Broilers fed SBM had longer villi, smaller crypts and increased villus height to crypt depth ratio compared with those fed RSM and MG diets. Broilers fed RSM diet had a lower caecal pH, and had 16.5% and 14.9% more branched chain fatty acid contents in caecal digesta compared with those fed SBM and MG diets, respectively, indicating more proteolytic fermentation.6. Replacing SBM by RSM and MG negatively affected growth performance and gut morphology. Hindgut protein fermentation was substantially increased in RSM fed birds.7. To a certain extent, retarded growth performance in RSM and MG fed birds could be counterbalanced by increasing the dietary level of digestible CP. 相似文献
73.
为比较冬闲地种草养鹅模式下不同鹅品种的生长发育、屠宰性能和肉品质,以28日龄四川白鹅、浙东白鹅、扬州鹅和霍尔多巴吉鹅为研究对象,采取全程草地放牧加补饲方式,每组3个重复,每个重复10只,于70日龄开展屠宰测定和肉品质测定。结果显示:①在整个生长发育期间,四个品种鹅在生长发育前期增重较大,后期趋于缓慢。在生长发育前期(28~49日龄),扬州鹅的周增重均不同程度地高于四川白鹅和浙东白鹅,但在36~42日龄时扬州鹅的体增重低于霍尔多巴吉鹅;在生长发育后期(50~70日龄),扬州鹅的体增重均高于其他三个品种鹅。②扬州鹅的屠宰率高于其他三个品种的鹅;扬州鹅的腹脂率为1.39%,显著低于其他三个品种鹅。③扬州鹅不同部位肌肉中水分含量最低,胶原含量最高;扬州鹅的胸肌中蛋白质含量显著高于其他三个品种鹅。综上所述,扬州鹅可作为种草养鹅的理想品种,研究结果为种草养鹅模式下适宜品种的选择提供了理论依据。 相似文献
74.
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76.
Jeong-Hyeon Cho Seunghyung Lee Bong-Joo Lee Sang-Woo Hur Kang-Woong Kim Maeng-Hyun Son Dong-Jae Yoo 《动物营养(英文)》2021,7(2):548
An 8-week feeding trial was conducted to determine the optimal dietary protein level for juvenile marbled flounder. Five semi-purified test diets were formulated to contain different protein levels (CP) including 42.7%, 47.4%, 53.3%, 58.8%, and 64.5% (dry matter), named as CP42.7, CP47.4, CP53.3, CP58.8, and CP64.5, respectively. Five hundred and twenty-five juveniles (6.0 ± 0.1 g) were randomly distributed into 15 tanks (300 L tanks), resulting in 35 fish per tank (n = 3 tanks). Fish were fed the test diets 5 times per day until satiation. The CP58.8 resulted in the highest gain in weight and the best efficiency in feed utilization among the tested protein levels (P < 0.05). Fish fed the CP58.8 diet showed significantly higher whole-body protein and lipid contents than the fish that were fed the other diets (P < 0.05). Fish fed the CP53.3, CP58.8, and CP64.5 diets showed a significantly higher dorsal-muscle lipid content than the fish that were fed the CP42.7 and CP47.4 diets (P < 0.05). The one-slope straight broken-line regression analysis on the results of the thermal growth coefficient and feed conversion ratio indicated that the estimated optimum dietary protein level was 58.8%. Taken together, it is suggested that the dietary protein level of 58.8% is optimal for better growth and high efficiency in feed utilization for the juvenile marbled flounder. 相似文献
77.
78.
先用34 头西门塔尔杂交阉牛,按年龄分为2±0.5 岁(8 头)、3±0.5 岁(9 头)、4±0.5 岁(8 头)、5~9 岁(9 头)4 个年龄组,进行了不同年龄组对育肥效果、屠宰性能影响的研究。结果表明,在相同饲养条件下,肉牛的增重速度(P< 0.01)、饲料转化率、大理石花纹等级(P< 0.05)及眼肌面积(P< 0.05)均以3 岁以下为好。随着年龄的增长,虽然屠宰率略微见增(P> 0.05),但肉的品质下降,饲养效果降低。 相似文献
79.
微量元素添加剂设计方法对肉兔生产性能的影响 总被引:3,自引:2,他引:3
选择35日龄健康比利时幼兔40只,随机分成2组,每组20只,在基础饲料及管理完全一致的条件下,分别添加按不同方法设计的微量元素添加剂。试验组在分析化验饲料中各种微量元素含量的基础上补加,使之达到营养标准;对照组不考虑饲料中的微量元素含量,按标准另外补加。试验期30天。结果:试验组和对照组日增重分别为29.6g和27.4g,料重比分别为3.39∶1和3.54∶1,试验组增重提高8.03%,差异显著(P<0.05),饲料利用率提高4.24%,添加剂成本降低24.74%,每千克增重降低饲料费0.16元。试验表明,在设计微量元素添加剂时,应考虑地方性饲料的特点及有关营养含量,以保持营养的平衡性。 相似文献
80.