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1.
Histochemical, ultrastructural and morphometric methods were used to study growth patterns of red, pink and white muscle fibres and their relation to body weight and total length in the fast-growing freshwater fish Piaractus mesopotamicus Holmberg. The correlations amongst body weight, body length and diameter of red, pink and white fibres were low. From 10-15 to 40-50 cm, body weight increased 102.7 times, while the diameter of each type of fibre increased by factors of 0.94, 0.74 and 0.70, respectively. Muscle fibres revealed different morphological and histochemical stages of maturation. The frequencies of < 20 microns fibres of red, pink and white muscle tissue in the youngest and oldest classes were 64.5 and 11.0, 38.2 and 7.7 and 24.0 and 1.4%, respectively. In 30-40 cm fish, the frequency of < 20 microns fibres in the red and pink tissue was 24.5 and 25.5%, while in the white tissue it was 11.5%. During sexual maturity (40-50 cm), the recruitment of < 20 microns fibres in white muscle was 1.4%. Muscle fibres of this species showed continuous growth by both hyperplastic and hypertrophic mechanisms, and hyperplasia was particularly active in the juvenile phase.  相似文献   

2.
1. In order to determine the feasibility of using high fibre diets in turkey rations, three crude fibre dietary concentrations were fed to turkey hens at three ages and performance, fibre digestibility and small intestinal morphology were determined. 2. Growth rate and feed efficiency decreased when diets contained 80 to 90 g crude fibre/kg; however, growth did not change when 60 g crude fibre/kg was fed between 1 and 4 weeks or between 6 and 8 weeks and was enhanced between 11 and 14 weeks of age. 3. Digestibilities of crude protein, fat and gross energy (GE) were depressed at fibre intakes of 80 to 90 g/kg between 1 and 4 weeks but not at later ages. Crude fibre digestibility increased with age and decreased with dietary fibre content. 4. Total small intestinal length and surface area were increased by high dietary crude fibre intake between 11 and 14 weeks. Small but inconsistent changes in the length, diameter and number of villi, villus size and area were observed in the duodenum, jejunum and ileum at the different ages as a result of feeding the different crude fibre concentrations. 5. Crude fibre can be utilised to some extent by turkeys and concentrations of 60 g fibre/kg in the diet did not result in decreased performance after 6 weeks of age.  相似文献   

3.
Muscle growth was studied in larvae of sea bass, Dicentrarchus labrax L., reared at two temperatures: real ambient temperature ( congruent with 15 degrees C during vitelline phase and increased gradually) and 19 degrees C from fertilization until the end of larval development. Muscle cellularity, body length and body weight were measured. Early temperature influenced larval development and so, pre-larval phase finished earlier at 19 degrees C than at ambient temperature (4 and 6 days, respectively). Temperature also affected muscle growth such that at hatching and at mouth opening hypertrophy of muscle fibres was greater at 19 degrees C (P < 0.05), whereas hyperplasia was similar in both groups. After 25 days, the cross-sectional area of the white muscle was greater at 19 degrees C (P < 0.05), which was mainly associated with a higher proliferation of new white muscle fibres. At this stage the body length was also higher at 19 degrees C. Metamorphosis finished earlier in fish reared at 19 degrees C (52 days) than at natural temperature (82 days). At this developmental stage body length and cross-sectional area of the myotome were similar in both groups. However, muscle cellularity differed between groups. Thus, hypertrophy of muscle fibres was higher in fish reared at ambient temperature (P < 0.05), whereas proliferation of new muscle fibres was higher at 19 degrees C (P > 0.05).  相似文献   

4.
本试验旨在研究妊娠后期母羊饲粮精料比例对羔羊生长性能、消化性能和血清抗氧化指标的影响。试验选用66只妊娠90 d、平均体重为(44.45±2.20)kg的初产湖羊,按照体重相近原则随机分为3组,每组11个重复,每个重复2只。各组母羊妊娠期饲粮精料比例分别为50%、40%和30%,分娩后母羊饲喂相同的全混合日粮(TM R)。羔羊10日龄,每只母羊取1只羔羊断母乳,饲喂代乳粉;15日龄补饲开食料;20日龄补饲苜蓿干草,自由采食至60日龄。每10 d测定1次羔羊体重,51~60日龄进行羔羊消化代谢试验,20和60日龄采集羔羊血液测定血清抗氧化指标。结果表明:妊娠后期母羊饲粮精料比例对羔羊1、10、20、30、40、50、60日龄体重,20、60日龄体尺指标及营养物质表观消化率均无显著影响(P0.05)。随母羊饲粮精料比例降低,20日龄羔羊血清总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)活性极显著升高(P0.01),60日龄50%组显著或极显著低于其他2组(P0.05或P0.01);30%组20和60日龄羔羊血清谷胱甘肽过氧化物酶(GSH-Px)活性极显著高于其他2组(P0.01);血清中MDA的含量在20日龄时随母羊饲粮精料比例的降低而极显著降低(P0.01),60日龄时50%组显著高于30%组(P0.05)。结果提示,妊娠后期母羊饲粮的精料比例对产后早期断奶羔羊的体重、体尺、营养物质表观消化率无显著影响,但随母羊饲粮精料比例的降低,羔羊血清的抗氧化能力提高。  相似文献   

5.
本试验旨在研究发酵豆粕替代鱼粉对大黄鱼(Larimichthys crocea)幼鱼生长性能、体成分、血清生化指标及肝脏组织形态的影响,探索发酵豆粕替代大黄鱼幼鱼饲料中鱼粉的适宜比例。以鱼粉、小麦蛋白粉为主要蛋白质源,鱼油、大豆油和大豆卵磷脂为主要脂肪源,配制含40%鱼粉的基础饲料。以发酵豆粕替代基础饲料中0(R0组,作为对照组)、15%(R15组)、30%(R30组)、45%(R45组)、60%(R60组)、75%(R75组)的鱼粉,并在除对照组饲料外的各饲料中添加适量晶体氨基酸(赖氨酸和蛋氨酸),配制6种等氮(蛋白质水平为45%)等脂(脂肪水平为10%)的试验饲料。养殖试验在海水网箱(1.5 m×1.5 m×2.0 m)中进行,每种试验饲料投喂3个网箱,每个网箱放养60尾初始体重为(10.49±0.03)g大黄鱼幼鱼,养殖时间持续56 d。结果表明:各组大黄鱼幼鱼的存活率无显著差异(P0.05),但随着发酵豆粕替代鱼粉比例的升高有下降趋势;与R0组相比,R15、R30、R45组的特定生长率(SGR)、增重率(WGR)、饲料系数(FCR)无显著变化(P0.05),进一步提高鱼粉替代比例(R60、R75组),SGR、WGR显著降低(P0.05),FCR显著升高(P0.05);各组全鱼粗蛋白质、粗脂肪、水分含量无显著差异(P0.05),随着发酵豆粕替代鱼粉比例的升高,全鱼粗灰分含量有上升的趋势;各组血清生化指标没有显著差异(P0.05),但随着发酵豆粕替代鱼粉比例的升高,血清中总胆固醇含量有下降趋势,谷丙转氨酶活力有升高趋势;通过肝脏组织学观察发现,发酵豆粕替代鱼粉比例超过30%后会造成肝脏细胞的损伤,替代比例越高损伤越严重。综合各项测定指标,本研究认为:发酵豆粕替代饲料(含40%鱼粉)中30%的鱼粉较为适宜,过高的替代比例会造成大黄鱼幼鱼肝脏组织病变,导致生长速度、存活率下降。  相似文献   

6.
Eight variants of recipes for mixtures of straw and concentrated feed with 10 to 60 per cent straw more or less finely ground (86 to 314 g crude fibre per kg dry matter) and fattening feed for lambs (50 g crude fibre per kg dry matter) were checked concerning the digestibility of crude nutrients for fullgrown wethers and 60 to 80-, 80 to 100-and 100 to 120-day-old lambs which had been ablactated at an age of 60 days. The digestibility for wethers was significantly higher than for lambs, between the age groups of which there were no significant differences concerning the digestibility. In accordance with the results with rations on the basis of concentrated feed as checked and described in the first piece of information, the content of crude fibres in the rations had a negative influence on the digestibility of organic matter, NFE and energy whereas there was a positive relation with the digestibility of crude fibres. The regression functions established for mixtures of straw and concentrated feed concerning the dependence of the digestibility on the content of crude fibres showed a relatively good coincidence in the range of a low content of crude fibres with the corresponding regression functions which were described in the first piece of information for rations of concentrated feed. The equations for the digestibility of crude fibres were an exception. In contrast to this, the quantitative relations between crude fibres and the digestibility as established in the first piece of information for rations with a low content of crude fibres cannot be transferred to rations with a higher content of crude fibres.  相似文献   

7.
Sixty-four Thoroughbred and Anglo-Arab mares aged 6-12 years were randomly allocated to 4 dietary groups and fed diets that differed in the total protein content and quality (essential amino-acids). Forty mares were non-lactating and 24 lactating. Eight mares were withdrawn from the investigation owing to injuries or gynaecological pathology. An overall conception rate of 94.6% and a foaling rate of 80% was achieved. Five of 14 (35.7%) mares (Group 1) fed a low-quality protein diet suffered from early embryonic loss before 90 days of pregnancy compared to 3 of 41 (7.3%) mares in the remaining groups that received the higher-quality protein in their diets. Serum progestagen concentrations of mares in Group 1 that suffered foetal loss were indicative of luteal function insufficiency during the 1st 40 days post-ovulation. Non-lactating mares in all 4 groups gained on average approximately 30 kg in mass during the 90 days before the breeding period. Lactating mares in Group 1 (low-quality protein) lost on average 25 kg in mass during lactation, with no weight loss observed among the lactating mares in the other 3 groups. No difference in the diameter of the embryonic vesicle was found between dietary groups until Day 35 of pregnancy.  相似文献   

8.
氨化小麦秸在阉牛生长育肥期的利用与效益分析   总被引:2,自引:0,他引:2  
选用24头乌珠穆沁品种生长期阉牛,进行连续90天的饲喂氨化与未氨化小麦秸的对比生长试验,结果表明。在阉牛生长育肥阶段,采用精料比例连续递进(40%→60%→80%)的饲养制度时,饲喂氨化麦秸较未氨化麦秸可使阉牛日粮干物质进食量(DMI)平均提高18%,日增重(ADG)平均提高34%,日粮精料转化效率(C/G)平均提高12.8%,每公斤增重的饲料费用(FC/G)平均降低0.16元.其中,在40%、60%和和80%精料比例下,饲喂氨化麦秸可使阉牛日粮DMI分别提高45.3%、19.1%和2.3%;ADG分别提高111.1%、39.1%和5.8%;C/G分别改进30.2%、11.4%和2.9%FC/G分别降低0.41、0.19和0.03元。在40%—80%精料比例范围内,给阉牛饲喂氨化秸可以提高动物的生产性能,但其提高幅度随日粮精料水平提高而下降。  相似文献   

9.
本试验旨在研究褪黑激素对獭兔生长性能及皮毛质量的影响。采用单因子试验设计,选取55~60日龄体重相近的健康生长獭兔200只,随机分为4组,每组50只兔。对照组饲喂基础饲粮,试验组分别饲喂含不同水平褪黑激素(10、25、40 mg/kg)的试验饲粮。试验期为99 d。结果表明:60~150日龄,各试验组平均日增重均极显著高于对照组(P0.01),各试验组料重比均极显著低于对照组(P0.01)。90、120、130、150日龄各试验组被毛密度均极显著高于对照组(P0.01)。40 mg/kg试验组臀部、肩部、腹部的皮张厚度均显著或极显著低于对照组(P0.05或P0.01)。由此可见,褪黑激素能够提高獭兔平均日增重,降低料重比,同时提高獭兔被毛密度,促进獭兔皮张提前成熟。  相似文献   

10.
本试验旨在探究南极磷虾粉替代鱼粉对圆斑星鲽幼鱼生长性能、血清和肝脏生化指标及血清非特异性免疫指标的影响。以鱼粉和玉米蛋白粉为蛋白质源,高筋粉为糖源,鱼油、豆油和磷脂为脂肪源配制基础饲料。以南极磷虾粉分别替代基础饲料中0(对照)、10%、20%、30%、40%、50%的鱼粉,配制6种等氮等脂的试验饲料(分别记为R0、R10、R20、R30、R40和R50),饲喂初始体重为(38.16±0.11)g的圆斑星鲽幼鱼50 d,每种饲料设3个重复,每个重复投喂30尾鱼。结果表明:1)R30、R40组圆斑星鲽幼鱼的增重率和饲料效率较高,显著高于其他各组(P0.05);R50组的死亡率显著高于其他各组(P0.05)。南极磷虾粉替代鱼粉水平对圆斑星鲽幼鱼的肝体比和脏体比没有产生显著影响(P0.05)。2)R10和R30组的血清总蛋白含量显著高于其他各组(P0.05);与对照组相比,南极磷虾粉替代10%~30%的鱼粉对圆斑星鲽幼鱼血清中谷草转氨酶和谷丙转氨酶以及肝脏中谷氨酸脱氢酶活性无显著影响(P0.05)。R40、R50组血清中谷草转氨酶和谷丙转氨酶活性与对照组相比显著升高(P0.05),R40组肝脏中谷草转氨酶活性较之对照组显著降低(P0.05),且R50组肝脏中谷丙转氨酶活性显著低于其他各组(P0.05)。3)与对照组相比,南极磷虾粉替代10%~30%的鱼粉可显著提高圆斑星鲽幼鱼血清中溶菌酶、碱性磷酸酶的活性(P0.05)。综合来看,南极磷虾粉替代10%~30%的鱼粉可以提高圆斑星鲽幼鱼的生长性能和非特异性免疫力,并对鱼体的肝脏功能和蛋白质代谢无不利影响。  相似文献   

11.
乌苏里貉生长发育规律研究及其生长曲线模型拟合   总被引:1,自引:1,他引:0  
选取60只分窝乌苏里仔貉,按出生窝别、出生时间、性别、体重分为4组,生长期和冬毛期分别饲喂4种不同的试验E/粮,研究其生长发育规律,拟合其体重和体长生长模型。结果表明:乌苏里貉周平均日增重在8~12周龄和18~24周龄有2个高峰期(分别为40g/d和50g/d),体长生长速度在9~14周龄和20~22周龄有2个高峰期(分别为0.3cm/d和0.2cm/d);体重和体长适宜生长曲线方程分别为:Y=241.47+42.242X+19.041X^2-0.399X^3(R^2=0.994),Y=9.517+3.374X-0.067X^2(R^2=0.992)。  相似文献   

12.
试验旨在研究饲喂含β-内酰胺类药物有抗奶对荷斯坦公犊牛生长发育和血液免疫指标的影响。选用3日龄、体重(42.64 kg±1.16 kg)相近的公犊牛18头,随机分为2组。对照组饲喂正常牛奶,试验组饲喂有抗奶,犊牛60日龄断奶,试验期为180 d。试验第10、20、30、40和50天分别采集正常牛奶和有抗奶,测定乳成分、大肠杆菌数和乳中抗生素含量。试验第30、60、90和180天逐头空腹称重,测量体尺,并计算平均日增重(ADG)。试验第7、15、30、60、90和180天于晨饲前对公犊牛空腹静脉采血,制备血清,测定血清免疫指标。结果显示:①试验牛场有抗奶中β-内酰胺类抗生素含量为268.65 μg/L,且有抗奶的乳蛋白含量、体细胞数(SCC)和大肠杆菌数显著高于正常牛奶(P<0.05);②饲喂有抗奶显著降低公犊牛第30天时的体重和试验60 d内的ADG(P<0.05),显著降低公犊牛第90天时的体长及第60和90天时的胸围(P<0.05);③与对照组相比,试验组公犊牛IgA在第30、60和90天时显著升高(P<0.05),IgM在第7天时显著升高(P<0.05),IgG在第30和60天时显著升高(P<0.05);IL-2和TNF-α在第15和30天时均显著升高(P<0.05)。结果提示,饲喂有抗奶明显降低犊牛哺乳前期日增重,且在一定程度上提高犊牛断奶前后的血清免疫指标水平。  相似文献   

13.
日粮维生素E水平对后备种母鸡生长发育的影响   总被引:3,自引:0,他引:3  
研究日粮维生素E对后备种母鸡体形、肌肉和生殖器官生长发育的影响。发现日粮维生素E水平对20周龄后备种母鸡的体重、体重均匀度、胸骨长度、胫长度、屠宰率、半净膛率、全净膛率、胸肌率、腿肌率、翅重率、腹脂率、冠高度和卵巢重量没有显著影响(P>0 05 ), 但高剂量维生素E日粮显著增加输卵管的长度和重量(P<0 05)。结果表明日粮高维生素E水平(180mg/kg) 可加速20周龄后备种母鸡输卵管的生长发育。  相似文献   

14.
试验旨在研究初乳巴氏杀菌与否对犊牛生长性能及胃肠道发育的影响。选取体重相近、健康状况良好的20头新生荷斯坦牛犊牛,随机分为2组,对照组犊牛饲喂未经过巴氏杀菌的初乳,试验组犊牛饲喂经过巴氏杀菌的初乳,试验期90 d。试验期间测量两组犊牛体重、平均日增重(ADG)、平均日采食量(ADFI)及料重比(F/G),同时观察犊牛腹泻情况,在0、30、60及90日龄测量两组犊牛体尺指标。结果显示,在90日龄时,与对照组相比,试验组犊牛的平均日采食量和平均日增重分别增加了1.74%和2.33%(P> 0.05),试验组犊牛管围和体斜长分别增加了2.68%和1.41%(P> 0.05),而腹泻率和料重比却分别降低了0.67%和2.40%(P> 0.05)。初乳巴氏杀菌与否对犊牛复胃重、小肠重及小肠长度的影响不显著(P> 0.05),但显著降低了犊牛复胃重与活体重比(P< 0.05)。综上所述,巴氏初乳对90日龄内犊牛的生长发育有一定促进作用。  相似文献   

15.
Nine semi‐purified diets were prepared with three levels each of protein (300, 350 and 400 g/kg) and lipid (60, 80 and 100 g/kg) and fed ad libitum to Trichogaster trichopterus fingerlings (0.61 ± 0.03 g) in triplicate groups (10 fish/replicate) for 90 days to determine optimum dietary protein and lipid levels. Twenty‐seven flow‐through fibre‐reinforced plastic tanks (200 l capacity each with 100 l of water) were used for rearing the fish. The dietary protein, lipid and their interactions had significant effects (p < 0.05) on weight gain, feed conversion ratio, specific growth rate, nutrient retention and digestibility, but not on hepato‐ and viscerosomatic indexes (p > 0.05). Dietary protein and the interaction of protein with lipid had significant effect (p < 0.05) on whole‐body dry matter, lipid and energy contents, but not on protein and ash contents (p > 0.05). But, the dietary lipid had significant (p < 0.05) effect on whole‐body dry matter, protein, lipid and energy contents except the ash contents (p > 0.05). For each level of dietary protein, the increase in dietary lipid resulted significant increase (p < 0.05) in whole‐body lipid contents without affecting the protein and ash contents (p > 0.05). Based on better growth and dietary performances, the optimum dietary protein and lipid levels of blue gourami fingerling are 350 and 80 g/kg diet respectively.  相似文献   

16.
An enzyme-linked immunosorbent assay (ELISA) using excretory-secretory antigens was developed to study the dynamics of the IgG antibody response to varying levels of Trichinella spiralis infection in the guinea pig. Four groups of four Hartley guinea pigs each were infected with 1250, 250, 50 or 10 T. spiralis infective muscle larvae. They were bled every 15 days for 6 months and the IgG antibody response determined by ELISA. The time of seroconversion was dose dependent as the larger the dose, the earlier the response occurred. Significant differences in antibody response between the dose groups were evident at 30 days post-infection (P less than 0.05). Beyond 60 days post-infection, the response was similar in the four groups. The antibody response in the groups infected with 250 and 50 infective larvae was similar, but was significantly different from that of the high (1250) and low (10) dose groups from 30 days post-infection (P less than 0.01). Once seroconversion occurred, the antibody titer rose to the same level, irrespective of the initial dose. To compare the antibody response according to muscle larvae recovered, the guinea pigs were grouped into four categories: less than 10 larvae; 10-25 larvae, 50-80 larvae, greater than 100 larvae. A significant positive correlation (P less than 0.05) was observed at 60 days post-infection when these groups were compared.  相似文献   

17.
The digestibility for crude protein, ether extract, crude fibre, ash and nitrogen-free extract were determined for palm kernel meal samples. The test diets, identified as DA, DB and DI, were formulated to contain 10%, 20% and 40% palm kernel meal, respectively. With the exception of crude fibre and crude protein the digestibility of the nutrients of the diets decreased significantly as the dietary fibre content increased.  相似文献   

18.
A cooperative study, using 231 primiand multiparous crossbred sows from six experiment stations (IN, KS, MI, MN, ND, and OH), was conducted to determine the effects of elevating dietary valine concentration in corn-soybean meal diets on lactational performance of sows nursing large litters. Crossbred sows were fed diets containing a minimum of .60% lysine during gestation. Sows were allotted at farrowing to four dietary valine concentrations, .80, .95, 1.10, and 1.25%. Crystalline L-valine replaced cornstarch to maintain a constant ratio of corn:soybean meal across diets. Dietary lysine, provided by corn, soybean meal, and .15% crystalline L-lysine x HCl, was .90% in all diets. Sows were allowed ad libitum access to feed. Sows were weighed within 24 h after farrowing, and all litters were adjusted to > or = 10 pigs/litter by d 2 following farrowing. Average sow parity, number of pigs on d 2, and lactation length for the four treatments were, respectively, 2.3, 2.3, 2.3, 2.5; 10.9, 10.8, 10.8, 10.7; and 25.1, 24.5, 25.2, 25.0 d. The ADFI during lactation was 5.87, 5.77, 5.87, and 5.74 kg (P > .50); hence, valine intakes were 41, 48, 55, and 61 g/d (linear, P < .01). Lysine intake ranged from 51.5 to 52.7 g/d (P > .50). Sow weight after farrowing averaged 198 kg (P > .60). Overall pig survival to weaning was high (>92%), and the number of pigs weaned (10.1, 10.3, 10.3, 10.3) did not differ (P > .30) among treatments. Litter weaning weights (73.6, 73.6, 74.5, 72.6 kg), litter weight gains (55.1, 55.1, 56.0, 54.1 kg), sow weight change during lactation (-4.9, -5.4, -4.8, -6.3 kg), and return-to-estrus interval (7.5, 6.4, 6.9, 8.2 d) were not affected (P > .30) by dietary valine. There were no station x treatment interactions (P > .50). These results indicate no benefit of elevated dietary valine for lactating sows nursing > or = 10 pigs and consuming a corn-soybean meal diet containing .90% lysine and .80% valine.  相似文献   

19.
辽宁绒山羊杂交改良子午岭黑山羊的效果及遗传分析   总被引:7,自引:1,他引:6  
本文对用辽宁绒山羊杂交改良子午岭山羊的生长发育、生产性能、绒纤维品质及遗传规律进行了分析,结果表明各代杂种羊的各个指标均较子午岭山羊有提高。杂种羊体重比子午岭山羊体重提高10%以上,子午岭成年母羊产绒量为115克,杂种一、二、三代分别为282、330、355克,产绒量显著提高(P<0.01),接近当地辽宁绒山羊(370克)。本文估测了高代杂种F_3主要经济性状的遗传参数,结果表明,体重、产绒量、绒纤维细度的遗传力分别为0.562、0.138、0.455。产绒量与体重、绒纤维的长度的遗传相关分别为0.674、0.882。绒纤维细度与体重的遗传相关为-0.086。根据估测的遗传参数,结合生产实际,提出选择指数I_8=-0.00425x_1+0.1898x_2+0.8785x_3,其中x_1=产绒量(克);x_2=体重(千克);x_3=细度(微米),可在生产中试用。  相似文献   

20.
The experiment was conducted to investigate the influence of different levels of zinc (Zn) on cashmere growth, plasma testosterone and Zn profile in male Cashmere goats. Twenty‐eight male Liaoning Cashmere goats, 3 years old and body weight at 56.2 ± 2.45 kg, were assigned to four groups. The animals were fed a basal diet containing of 45.9 mg Zn/kg dry matter (DM) basis and supplemented with 0, 20, 40 or 80 mg Zn (reagent grade ZnSO4·7H2O) per kg DM for 90 days. There was no significant effect on growth and diameter of cashmere fibre for Zn supplemented in diets. However, the length and growth rate of wool were improved (p < 0.05) with dietary Zn. The length and growth rate of wool were higher (p < 0.05) for the groups supplemented with 40 or 80 mg Zn/kg DM compared with that of 20 mg Zn/kg DM treatment group. Plasma testosterone concentration was increased for Zn supplemented in diets, and the testosterone concentration was higher (p < 0.05) in goats fed on the diet supplemented with 40 or 80 mg Zn/kg DM compared with those fed on basal diet. Plasma Zn concentrations increased (p < 0.05) with increasing dietary Zn and supplemented with 40 and 80 mg Zn/kg DM groups improved plasma Zn concentration (p < 0.05) more than 20 mg Zn/kg DM group. Fibre Zn content was higher (p < 0.05) in groups supplemented with 40 or 80 mg Zn/kg DM compared with control group, but no difference between Zn‐supplemented groups (p > 0.05). The activity of plasma alkaline phosphatase was increased (p < 0.05) due to dietary Zn supplementation; however, no difference was found between supplemented treatment groups (p > 0.05). In conclusion, Zn content (45.9 mg Zn/kg DM) in control diet was insufficient for optimal wool growth performance, and we recommended the level of dietary Zn for such goats is 86 mg/kg DM during the breeding season and cashmere fibre growing period.  相似文献   

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