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1.
《农业科学学报》2023,22(6):1833-1846
This study investigated the effects of dioscorea opposite waste (DOW) on the growth performance, blood parameters, rumen fermentation and rumen microbiota of weaned lambs. Sixty healthy weaned Small-Tailed Han lambs (male, (22.68±2.56) kg initially) were used as the experimental animals. Four levels of concentrate: 0 (control, CON), 10% (DOW1), 15% (DOW2) and 20% (DOW3), were replaced with DOW in the basal diet as experimental treatments. The results showed that lambs fed the DOW2 diet had a higher (P<0.05) dry matter intake (DMI) than the other groups. There was no significant difference (P>0.05) among DOW groups in average daily weight gain (ADG), and replacing concentrate with DOW linearly or quadratically increased (P<0.05) the ADG, while lambs fed the DOW2 diet showed greater (P<0.05) ADG than the CON group. The relative plasma concentration of growth hormone (GH), insulin like growth factor-1 (IGF-1) and insulin were affected by DOW, replacing concentrate with DOW linearly or quadratically (P<0.05) enhanced the plasma concentration of GH, IGF-1 and insulin, which was significantly higher (P<0.05) in the DOW2 group than in the CON, DOW1 and DOW3 groups. In addition, the DOW treatment showed a lower (P<0.05) concentration of blood urea nitrogen (BUN) than the CON group. Replacing concentrate with DOW quadratically decreased (P<0.05) the ruminal ammonia nitrogen (NH3-N) and increased (P<0.05) the total of volatile fatty acids (TVFAs) at 0 and 4 h after feeding as well as linearly decreased (P<0.05) the NH3-N at 8 h after feeding. Replacing concentrate with DOW linearly decreased (P<0.05) the propionate and increased the aceate before feeding, and linearly decreased (P<0.05) propionate and quadratically increased (P<0.05) the aceate at 4 and 8 h after feeding. Lambs fed the DOW2 diet increased the phylum Firmicutes and genera Succiniclasticum and Ruminococcus_1 groups, whereas decreased (P<0.05) the relative abundance of phylum Deferribacteres and genera intestinimonas and Ruminiclostridium. In summary, replacing the concentrate with 15% DOW was beneficial for improving the rumen fermentation and ADG by increasing the DMI and modulating the rumen microbial community.  相似文献   

2.
The present study aimed to investigate the effect of relative humidity(RH) at either acute or chronic moderate ambient temperature(Ta) on growth performance and droppings' corticosterone metabolites of broilers.Two experiments were conducted: effect of RH(35,60 or 85%) on average daily feed intake(ADFI) and droppings' corticosterone metabolites at acute(1 d: 20–26 or 31–20°C,26 or 31°C for 6 h d–1 at 10:00–16:00) moderate Ta(experiment 1) and effect of RH(35,60 or 85%) on growth performance and droppings' corticosterone metabolites at chronic(step-wisely increasing temperature by 3°C every 3 d from 20 to 32°C within 15 d: 20–23–26–29–32°C) moderate Ta(experiment 2).Droppings were collected at the 2,4,6,8,and 22 h after Ta-RH controlled in experiment 1 and at the 2,4,6,and 22 h after Ta controlled to 32°C in experiment 2.The results showed that: 1) In experiment 1,85% RH increased(P0.05) the droppings' corticosterone metabolites at the 2,6,8,and 22 h and 35% RH increased(P0.05) it at the 2 and 22 h compared to the 60% RH.Moreover,85% RH further increased(P0.05) it compared to the 35% RH,however,no difference(P0.05) was found in ADFI among the three RH groups at acute moderate 26°C; 35 and 85% RH increased(P0.05) droppings' corticosterone metabolites at the 2,6,8 and 22 h and decreased(P0.05) ADFI compared to the 60% RH,moreover,85% RH further increased(P0.05) droppings' corticosterone metabolites and further decreased(P0.05) ADFI compared to the 35% RH at acute moderate 31°C; and the average of droppings' corticosterone metabolites in the whole period had a negative correlation(P0.02) with the ADFI.2) In experiment 2,85% RH increased(P0.01) droppings' corticosterone metabolites only at the 2 h and decreased(P0.02) ADFI and average daily gain(ADG) compared to the 60% RH,no difference(P0.05) in droppings' corticosterone metabolites was found between the 35 and 60% RH,however,35% RH decreased(P0.01) ADG compared to the 60% RH,and the average of droppings' corticosterone metabolites in the whole period also had a negative correlation(P0.02) with ADFI and ADG.In conclusion,droppings' corticosterone metabolites could be used as a RH stress index and low and high RH,especially high RH,reduced growth performance possibly through inducing RH stress at moderate temperature.  相似文献   

3.
The objective of this study was to observe the forage yield, silage fermentative quality, anthocyanin stability, and antioxidant activity during the storage period and in vitro rumen fermentation of anthocyanin-rich purple corn (Zea mays L.) stover (PS) and sticky corn stover (SS). Forage yield of corn stover was weighed and ensiled with two treatments: (1) hybrid sticky waxy corn stover (control), and (2) hybrid purple waxy corn stover (treatment). Samples were stored in mini-silos for periods of 0, 7, 14, 21, 42, 63, 84, and 105 d. The results showed that PS had significantly higher (P<0.05) yields of dry matter (DM), organic matter (OM), gross energy (GE), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and total anthocyanins than that of the SS. Anthocyanin-rich purple corn stover silage (PSS) showed higher (P<0.05) levels of DM and CP relative to the sticky corn stover silage (SSS). Although anthocyanin-rich PSS displayed a lower (P<0.05) level of pelargonidin-3-glucoside (P3G), it had higher (P<0.05) levels of peonidin (Peo) and pelargonidin (Pel) compared to the control. Delphinidin (Del) and malvidin (Mal) were not detected in SSS during the ensilage period; in PSS, Del was no longer detected after 7 d of ensilage. Specifically, total anthocyanins in anthocyanin-rich PSS decreased rapidly (P<0.05) prior to 7 d of ensilage, and then remained at relatively stable (P>0.05) constants. Compared to the anthocyanin-rich PSS, SSS displayed significantly higher (P<0.05) pH value and ammonia nitrogen (NH3-N) content. Propionic acid (PA) at 0 d and butyric acid (BA) during the entire study period were not detected, whereas anthocyanin-rich PSS showed a higher (P<0.05) level of lactic acid (LA) than that of the SSS. Compared with the SSS extract, anthocyanin-rich PSS extract showed a higher (P<0.05) level of 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and displayed a lower (P<0.05) half maximal inhibitory concentration (IC50) value. Moreover, anthocyanin-rich PSS reduced (P<0.05) gas production (GP), and displayed lower levels of immediately soluble fraction and ratio of acetic acid (AA) to PA at 12 h, but the other parameters were unaffected (P>0.05) relative to the control. Taken together, the results indicated that: (1) anthocyanins could be stable in silage; (2) anthocyanin-rich PSS showed better silage fermentative quality and stronger antioxidant activity; and (3) anthocyanin-rich PSS had no negative effect on rumen fermentation parameters.  相似文献   

4.
The present study was conducted to evaluate the effect of dietary mulberry(Morus alba L.) leaves powder(MLP) supplementation on meat quality of finishing pigs.A total of 40 Duroc×Landrace×Yorkshire pigs(initial body weight of(40.5±0.63) kg) were randomly allotted into two treatments,fed either with control diet or 15% MLP diet for 85 d.The results showed that MLP diet decreased(P≤0.05) average daily gain(ADG) and increased(P0.05) feed/gain ratio(F/G) in the finishing and whole period.MLP diet also decreased(P0.05) carcass weight,dressing percentage,last rib and average backfat depth.However,MLP diet increased(P0.05) intramuscular fat(IMF) content,decreased(P0.05) shear force,cooking loss and drip loss.In addition,MLP diet increased(P0.05) total antioxidative capacity,glutathione peroxidase and tended(P0.10) to increase total superoxide dismutase in serum.In longissimus thoracis,myosin heavy chain(MyHC) I and IIa mRNA levels were increased(P≤0.05) for MLP diet.In conclusion,15% MLP supplementation reduced the growth performance and carcass traits,but improved meat quality of finishing pigs possibly through the change of myofiber characteristics,enhancement of antioxidative capacity and increase of IMF.  相似文献   

5.
【目的】对比大豆异黄酮和抗生素对文昌鸡生长性能、肉品质及血浆抗氧化指标的影响,为大豆异黄酮在文昌鸡生产中的实际应用提供参考。【方法】选用1日龄文昌鸡母雏540只。试验分3组,包括空白对照组、抗生素组和大豆异黄酮组,每组4个重复,每个重复45羽。分小鸡、中鸡和大鸡3个阶段进行试验。【结果】生长性能结果显示,1~30日龄小鸡各组之间的平均日增质量、平均日采食量和料重比均无显著差异(P0.05);31~80日龄阶段,大豆异黄酮组的平均日增质量显著高于对照组(P0.05);81~120日龄阶段,大豆异黄酮组的平均日采食量显著高于对照组(P0.05)。肉品质结果显示,各组的肉色L*、a*、b*和pH差异均不显著(P0.05);与对照组相比,大豆异黄酮组的熟肉率显著提高(P0.05)。血浆抗氧化指标结果显示,31~80日龄阶段,大豆异黄酮组的总抗氧化能力(Total antioxidant capacity,T-AOC)活性显著高于抗生素组(P0.05);81~120日龄阶段,大豆异黄酮组的肌酸激酶(Creatine kinase,CK)活性显著低于抗生素组,谷胱甘肽(Glutathione,GSH)含量显著高于抗生素组,抗生素组和大豆异黄酮组的T-AOC活性显著高于对照组(P0.05)。【结论】中鸡阶段饲粮中添加20 mg·kg~(–1)大豆异黄酮可以提高鸡日增质量和抗氧化水平;大鸡阶段饲粮中添加15 mg·kg~(–1)大豆异黄酮能够提高鸡采食量、熟肉率和抗氧化水平。  相似文献   

6.
Early life intervention is important to shape the gut microbiome profiles of adult animals due to the tremendous alteration of diet components. Nevertheless, there is still no unified understanding about its long-term effects in lambs. In this study, sixty 20-day-old lambs were assigned into ewe-rearing (ER) and artificial-rearing (AR) treatments to evaluate the effects of AR strategy on ruminal microbiota, fermentation, and morphology of pre-weaning lambs (from 20 to 60 days of age) and its long-term effects in the fattening stage (from 61 to 180 days of age). During the pre-weaning stage, ER lambs were breastfed and supplemented starter, while AR lambs were artificially fed with milk replacer and starter. During the fattening stage, all lambs in both treatments were fed with the same fattening diets. At 60, 120 and 180 days of age, 6 lambs from each group were slaughtered to collect rumen content and tissue samples. Compared with ER lambs, the dry matter feed intakes of AR lambs increased (P<0.05) from 20 to 180 days of age, companying an increased average daily gain (ADG) from 61 to 120 days of age (P<0.05) and from 121 to 180 days of age (0.05<P<0.1). Although there was no difference in short-chain fatty acid (SCFA, including acetate, propionate, and butyrate) between treatments before weaning (P>0.05), it was higher (P<0.05) in AR lambs compared with ER lambs at the fattening stage. The rumen keratin layer of AR lambs was thinner (P<0.05) than that of ER lambs. Along with lamb growth from 60 to 180 days of age, the differences in rumen bacterial diversity between AR and ER treatments grew more distinct (P<0.05). Compared with ER lambs, AR lambs increased (P<0.05) rumen bacteria abundance, such as phylum Spirochaetes and genus Treponema at 60 days of age, phylum Actinobacteria and genus Succiniclasticum at 120 days of age, and phylum Proteobacteria at 180 days of age, but decreased genus Selenomonas from 60 to 180 days of age, and Anaerovibrio at 180 days of age. In summary, the early interventions before weaning could improve dry matter feed intake of lambs, which triggered robust rumen development and produced positive long-term effects on rumen fermentation and noticeable weight gain of fattening lambs. It suggests that the artificial rearing strategy is effective in improving rumen fermentation and microbial maturity of intensive fattening lambs.  相似文献   

7.
The effects of breed, sex and birth parity on the traits of growth, carcass and meat quality were investigated in three different breeds including Swedish Landrace, British Large White and an indigenous Chinese breed — Tongcheng pigs. The results indicated that the Swedish Landrace and the British Large White had advantages over the Tongcheng pigs in growth rate, feed conversion rate (FCR) and carcass traits, but had disadvantages in meat quality. In contrast to the British Large White, the Swedish Landrace had higher average daily gain during the trial (ADG2) (877.04 g·day−1 vs. 813.95 g·day−1, P < 0.05), and marbling score (MS) (2.48 vs. 2.02, P < 0.01), larger eye muscle area (EMA) (41.80 cm2 vs. 35.14 cm, P < 0.01) and more efficient feed conversion rate (FCR) (3.06 vs. 3.29, P < 0.05), lower muscle shear force (MSF) (4.20 kgf (1 kgf = 9.80665 N) vs. 4.93 kgf, P < 0.05) and backfat thickness (BF) (all P < 0.01) including live backfat thickness (LBF), average backfat thickness at 3 points in the carcass (ABF), backfat thickness between 6th and 7th ribs (6–7 th BF) and backfat thickness at 10th rib (10 th BF). There was a difference (P < 0.05) only inMS between castrated females (CF) and castrated males (CM). Birth parity affected ADG2 (P < 0.05), some carcass characteristics and meat quality, including CL1 (P < 0.001), CL2 (P < 0.05), BF (ABF, 6–7th BF and 10th BF, all P < 0.001), EMD (P, 0.001), EMA (P < 0.001), percentage of leaf and caul fat (PLC) (P < 0.05), proportion of lean and bone of the ham (PLBH) (P < 0.05), muscle drip loss percentage (DL) (P < 0.05) and intramuscular fat content (IMF) (P < 0.05). The breed-sex interaction only impacted the average daily gain from birth to marketing (ADG1) and DL (both P < 0.05). However, there was no significant effect of sex-parity interaction on all the traits tested.  相似文献   

8.
Early bacterial colonization and succession within the gastrointestinal tract have been suggested to be crucial in the development of host immunity. In this study, we have investigated the changes in live weight and concentrations of selected serum parameters in relation to their fecal bacterial communities as determined by high throughput sequencing of the 16S rRNA gene over the same period in lambs. The results showed that lambs’ growth performance, the serum parameters, fecal bacterial community and fecal bacterial functions were all affected (P<0.05) by age of the lambs. Similarity within age groups of fecal microbiota was lower in the preweaning period and increased sharply (P<0.05) after weaning at 60 days. The similarity between the samples collected from birth to 90 days of age and those collected at 120 days of age, increased (P<0.05) sharply after 30 days of age. Some age-associated changes in microbial genera were correlated with the changes in concentrations of immune indicators, including negative (P<0.05) correlations between the relative abundance of Lachnospiraceae UCG-010, Eubacterium coprostanoligenes group, Ruminococcaceae UCG-005, Ruminococcaceae UCG-009, Ruminococcaceae UCG-013, Ruminiclostridium 6, Ruminococcaceae UCG-008, and Oscillibacter with serum concentrations of lipopolysaccharide (LPS), D-lactate dehydrogenase (DLA), immunoglobulin (IgA, IgM, and IgG), and cytokines (interleukin-1β (IL-1β), IL-6, IL-12, and IL-17), tumor necrosis factor-α (TNF-α), and the relative abundance of these genera increased from 45 days of age. In conclusion, these results suggested that the age-related abundances of particular genera were correlated with serum markers of immunity in lambs, and there might be a critical window in the period from birth to 45 days of age which provide an opportunity for potential manipulation of the fecal microbial ecosystems to enhance immune function.  相似文献   

9.
Two experiments were conducted to investigate the effect of in ovo zinc(Zn) injection on the embryonic development, tissue Zn contents, antioxidation and related gene expressions of fertilized eggs of Arbor Acres broiler breeders. Experiment 1 was conducted to determine an optimal embryonic age for early in ovo injection. A total of 720 fertilized eggs with similar weights were randomly allotted to 4 treatments with 6 replicates per treatment and 30 eggs per replicate in a completely randomized design. The eggs were injected with 0.1 m L sterilized water at 3, 6 and 9 embryonic days of incubation(E3, E6 and E9) or non-injection(the control), respectively. The results from experiment 1 showed that E3 and E6 injections increased(P0.05) the embryonic mortalities, and decreased(P0.05) hatchabilities compared to the non-injected control, but no differences(P0.05) between E9 injection and the non-injected control were observed in either embryonic mortality or hatchability. The findings suggest that the E9 is the optimal embryonic age for early in ovo injection. In experiment 2, a total of 672 fertilized eggs with similar weights were randomly allocated to 7 treatments with 6 replicates per treatment and 16 eggs per replicate in a completely randomized design. The eggs were injected with 0(the negative control), 50, 100, 150, 200, or 250 μg Zn/egg as reagent grade Zn SO4·7 H2 O in a 0.1-m L solution, or non-injection(the positive control), respectively at E9–10. The results from the experiment 2 demonstrated that no differences(P0.05) among 50 and 100 μg Zn/egg groups and the negative control were observed in the embryonic mortality and hatchability, however, the injection of 200 μg Zn/egg increased(P0.05) the embryonic mortality, and injections of 150 and 200 μg Zn/egg decreased(P0.05) hatchabilities compared with the controls. The embryonic tibia Zn contents at E20 were increased(P0.05) by injections of 150, 200 and 250 μg Zn/egg. Zinc injection did not affect(P0.05) malonaldehyde(MDA) contents, copper-and Zncontaining superoxide dismutase(Cu Zn SOD) activities and m RNA expression levels in the liver and heart of chick embryos at E15 and E20. Compared with the negative control, injections of 50, 150 and 200 μg Zn/egg up-regulated(P0.05) the metallothionein(MT) mR NA expression levels in the embryonic liver at E20. These results indicated that in ovo Zn injections increased Zn contents in the embryonic tibia and MT m RNA expression levels in the embryonic liver at E20, however, injections of 150–200 μg Zn/egg were harmful to the embryonic development.  相似文献   

10.
《农业科学学报》2019,18(6):1321-1328
An experiment was conducted to investigate the effect of relative humidity(RH) at chronic temperature on growth performance, glucose consumption, and mitochondrial adenosine triphosphate(ATP) production of broilers. A total of 180 28-day-old Arbor Acres broilers(half males and half females) were randomly allocated to three treatments, each containing six replicates of 10 birds per treatment, using a completely randomized design. Birds were reared at 35, 60 or 85% RH at 32°C for 15 days(temperature increased by 3°C every 3 days from 20 to 32°C within 15 days: 20–23–26–29–32°C). RH affected(P0.05) average daily feed intake(ADFI), average daily gain(ADG), average daily water consumption(ADWC), blood glucose concentrations, muscle glycogen levels, avian uncoupling protein(av UCP) mRNA expression, and cytochrome c oxidase(CCO) activity in liver of broilers at 42 days of age. The 85% RH decreased(P0.05) ADFI, ADG and ADWC; 35% RH decreased(P0.02) ADG. Both 85 and 35% RH increased(P0.01) blood glucose and decreased(P0.05) muscle glycogen. Both 85 and 35% RH increased(P0.05) av UCP mRNA expression. 35% RH decreased(P0.05) CCO activity. In conclusion, both high and low RH inceased glucose consumption and reduced mitochondrial ATP poduction, leading to a decline in growth rate.  相似文献   

11.
Twenty-eight male, weaned Chinese Holstein calves((156.8±33.4) kg) were used to investigate the effects of dietary forage to concentrate ratio(F:C) and forage length on nutrient digestibility, plasma metabolites, ruminal fermentation, and fecal microflora. Animals were randomly allocated to four treatments in a 2×2 factorial arrangement: whole-length forage(WL) with low F:C(50:50); WL with high F:C(65:35); short-length forage(SL) with high F:C(65:35); and SL with low F:C(50:50). Chinese wildrye was used as the only forage source in this trial. The grass in the SL treatments was chopped using a chaff cutter to achieve small particle size(~50% particles 19 mm). Dry matter intake(DMI) and organic matter(OM) intake was increased by increasing both F:C(P0.01) and forage length(FL)(P0.05), while acid detergent fiber(ADF) and neutral detergent fiber(NDF) intakes were only increased by increasing the F:C(P0.01). The digestibility of NDF was increased as the FL increased(P0.01), and it was also affected by interaction between F:C and FL(P0.05). Cholesterol(CHO)(P0.01), leptin(LP)(P0.05), and growth hormone(GH)(P0.01) concentrations in plasma were increased as dietary F:C increased. A significant increase in plasma triglyceride(TG)(P0.01), insulin(INS)(P0.05), and GH(P0.01) levels was observed with decreasing dietary FL. Ruminal p H values of calves fed with low F:C diets were significantly lower than those in high F:C treatment(P0.05). Increasing the F:C enhanced ruminal acetic acid(P0.05) and acetic acid/propionic acid(P0.01). Fecal Lactobacillus content was significantly higher, while Escherichia coli and Salmonella contents were significantly lower in WL and high F:C groups(P0.05). Lower fecal scores(higher diarrhea rate) were observed in calves fed with SL hay compared to WL hay(P0.05). Denatured gradient gel electrophoresis(DGGE) bands and richness index(S) were significantly affected by the interaction between F:C and FL(P0.05), under high F:C, band numbers and richness index from WL group were higher than that from SL group(P0.05), whereas there were no differences between WL andSL groups under low F:C(P0.05). Microflora similarity was 50–73% among the different treatments. It is concluded that the WL with high F:C(65:35) diet is suitable for weaned calves.  相似文献   

12.
以宁麦13和徐麦31两种小麦(Triticum aestivum)品种为材料,通过盆栽试验研究了不同pH值酸雨对小麦产量和籽粒品质的影响。结果表明:模拟酸雨抑制了小麦的生长,减少了生物量的积累。pH值2.0酸雨处理后宁麦13的单穗粒数和单茎产量分别较对照下降了48.6%和56.7%,徐麦31则分别下降了31.2%和39.7%,差异显著。小麦籽粒主要营养成分对酸雨胁迫响应不同,酸雨处理提高了籽粒氨基酸、蛋白质含量,pH值2.0酸雨处理后,宁麦13和徐麦31小麦籽粒中氨基酸含量分别比对照高36.6%和30.9%,总蛋白含量分别比对照高20.6%和15.1%,均与对照差异显著。而小麦可溶性糖、淀粉和脂肪含量较对照降低,且总体表现为酸度增强变化幅度增大。不同蛋白组分也对酸雨胁迫反应不同,酸雨处理提高了籽粒中清蛋白和球蛋白含量,而降低了谷蛋白含量和谷/醇。pH值2.0的酸雨处理后,宁麦13和徐麦31的清蛋白含量较对照分别增加了13.1%和23.9%,但与对照差异不显著。酸雨胁迫降低了总淀粉和支链淀粉含量,宁麦13和徐麦31的pH值2.0酸雨处理总淀粉含量分别较对照下降了11.8%和20.2%,与对照差异显著,但对直链淀粉含量影响不明显。可见酸雨不仅影响小麦的产量,而且对品质也有明显影响。酸雨处理尽管提高了籽粒总蛋白含量,但降低了谷蛋白和谷/醇,降低了其加工品质。  相似文献   

13.
《农业科学学报》2023,22(7):2041-2053
Light deficiency is a growing abiotic stress in rice production. However, few studies focus on shading effects on grain yield and quality of rice in East China. It is also essential to investigate proper nitrogen (N) application strategies that can effectively alleviate the negative impacts of light deficiency on grain yield and quality in rice. A two-year field experiment was conducted to explore the effects of shading (non-shading and shading from heading to maturity) and panicle N application (NDP, decreased panicle N rate; NMP, medium panicle N rate; NIP, increased panicle N rate) treatments on rice yield- and quality-related characteristics. Compared with non-shading, shading resulted in a 9.5–14.8% yield loss (P<0.05), mainly due to lower filled-grain percentage and grain weight. NMP and NIP had higher (P<0.05) grain yield than NDP under non-shading, and no significant difference was observed in rice grain yield among NDP, NMP, and NIP under shading. Compared with NMP and NIP, NDP achieved less yield loss under shading because of the increased filled-grain percentage and grain weight. Shading reduced leaf photosynthetic rate after heading, as well as shoot biomass weight at maturity, shoot biomass accumulation from heading to maturity, and nonstructural carbohydrate (NSC) content in the stem at maturity (P<0.05). The harvest index and NSC remobilization reserve of NDP were increased under shading. Shading decreased (P<0.05) percentages of brown rice, milled rice, head rice, and amylose content while increasing (P<0.05) chalky rice percentage, chalky area, chalky degree, and grain protein. NMP demonstrated a better milling quality under non-shading, while NDP demonstrated under shading. NDP exhibited both lower chalky rice percentage, chalky area, and chalky degree under non-shading and shading, compared with NMP and NIP. NDP under shading decreased amylose content and breakdown but increased grain protein content and setback, contributing to similar overall palatability to non-shading. Our results suggested severe grain yield and quality penalty of rice when subjected to shading after heading. NDP improved NSC remobilization, harvest index, and sink-filling efficiency and alleviated yield loss under shading. Besides, NDP would maintain rice’s milling, appearance, and cooking and eating qualities under shading. Proper N management with a decreased panicle N rate could be adopted to mitigate the negative effects of shading on rice grain yield and quality.  相似文献   

14.
This experiment was conducted to evaluate the effects of Bupleurum extract(BE) on blood metabolites, antioxidant status, and immune function in dairy cows under heat stress. Forty lactating Holstein cows were randomly assigned to 1 of 4 treatments. The treatments consisted of 0, 0.25, 0.5, and 1.0 g of BE kg–1 dry matter. Supplementation with BE decreased(P0.05) blood urea nitrogen(BUN) contents and increased blood total protein(TP) and albumin(ALB) levels compared with control cows, but it had no effects(P0.05) on blood glucose(GLU), nonesterified fatty acid(NEFA), total triglyceride(TG), low-density lipoprotein cholesterol(LDL-C), and high density lipoprotein cholesterol(HDL-C). Compared with control cows, cows fed BE had higher(P0.05) superoxide dismutase(SOD) and glutathione peroxidase(GSH-Px) activity. However, supplementation with BE had no effect(P0.05) on total antioxidant capacity(T-AOC) or malondialdehyde(MDA) levels. The immunoglobulin(Ig) A and G contents increased(P0.05) in cows fed 0.25 or 0.5 g of BE kg–1. Interleukin(IL)-2 and IL-4 levels were higher(P0.05) in cows fed 0.5 and 1.0 g of BE kg–1, and IL-6 was significantly elevated(P0.05) in cows fed 0.5 g of BE kg–1. There were no treatment effects(P0.05) on the CD4+ and CD8+ T lymphocyte ratios, CD4+/CD8+ ratio, or tumor necrosis factor-α(TNF-α) level among the groups. These findings suggest that BE supplementation may improve protein metabolism, in addition to enhancing antioxidant activity and immune function in heat-stressed dairy cows.  相似文献   

15.
The objective of this study was to investigate the effect of lairage after transport on post mortem muscle glycolysis, protein phosphorylation and lamb meat quality. Two preslaughter animal treatments, transport for 3 h and lairage for 0 h (T3L0) and transport for 3 h and then lairage for 12 h (T3L12), were compared with a control treatment of 0 h transport and 0 h lairage. Data obtained showed that preslaughter transport had a significant effect on lamb meat quality. Loins from lambs of the T3L0 treatment showed higher (P=0.026) pH24 h and higher (P=0.021) pH48 h values, but lower (P<0.001) drip loss and lower (P<0.05) glycolytic potential at 0 h post mortem than those of the T3L12 and control groups. Muscle samples of the T3L0 group showed higher (P=0.046) shear force and lower (P=0.005) b* value than those of the T3L12 group. Muscle glycogen concentration at 0, 2, 4 h post mortem were lower (P<0.05) in the T3L0 group than in control. No significant difference (P>0.05) in most meat quality parameters was determined between the T3L12 group and control, showing lairage for 12 h allowed lambs to recover from the effects of transport for 3 h and resulted in similar meat quality characteristics compared to no transport. Lairage after transport did not affect most meat quality indices in comparison with control, but increased the meat drip loss and b* value of lambs possibly through decreasing glycogen concentration and glycolytic potential.  相似文献   

16.
This study aimed to examine changes in phosphorylation of sarcoplasmic and myofibrillar proteins from longissimus lumborum, semitendinosus, and psoas major muscles during postmortem ageing for 5 d. These sarcoplasmic and myofibrillar proteins were separated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and stained with phosphorous and protein specific stains. Myofibril fragmentation index, pH, the content of lactic acid and the relative activity of μ-calpain in three ovine muscles were measured. These results showed that the relative phosphorylation level of sarcoplasmic and myofibrillar proteins of psoas major muscle were lower compared with longissimus lumborum and semitendinosus muscles (P<0.05). The pH of psoas major muscle was the lowest at 0.5 h postmortem, and the highest after 12 h postmortem (P<0.05). In addition, the relative activity of μ-calpain was higher within 5 d postmortem and myofibril fragmentation index was higher after 1 d postmortem in psoas major muscle than those of longissimus lumborum and semitendinosus muscles (P<0.05). The sarcoplasmic protein phosphorylation may regulate the rate of pH decline to influence the μ-calpain activity and then proteolysis of proteins consequently. This study gives a new perspective of the mechanism of postmortem meat tenderization.  相似文献   

17.
Genotyping for locus PGR (progesterone receptor gene) of the Holstein servicing bulls (World Wide Sires) was carried out. The frequencies of alleles and genotypes of this locus are given. Significant (P < 0.05) superiority of the homozygous genotype AA of locus PGR was found in relation to the heterozygous genotype AG for several economically valuable traits: PTAM (predicted transmitting ability for milk, 380 points), PL (productive life, by 1.3 months), and FE (feed cost–feeding efficiency index, 37 points). Significant superiority (P < 0.05) of the homozygous genotype GG over the heterozygous genotype AG for the PL trait was also found, by 1.2 months. The obtained data can be used for marker-dependent breeding.  相似文献   

18.
Recently, saccharicterpenin extracted from Camellia oleifera seed meal has become a widely used feed supplement in animal husbandry. In order to assess its safety, this study was designed to investigate the toxicity and histopathological effects of saccharicterpenin on piglets. One hundred-fifty weaned pigs((Yorkshire×Landrace)×Duroc), 75 males and 75 females with body weight(BW) of(7.35±0.29) kg, were randomly allotted to groups receiving diets supplemented with 0, 500, 1 000, 2 500 or 5 000 mg kg~(–1) saccharicterpenin for 70 d. The diet with 500 mg kg~(–1) saccharicterpenin supplementation improved liver glutathione peroxidase(GSH-Px) activity, and the diet with 1 000 mg kg~(–1) saccharicterpenin supplementation improved liver glutathione S-transferase(GSH-S) activity in piglets on d 70(P0.05). At 2 500 mg kg~(–1), saccharicterpenin in the diets reduced average daily feed intake(ADFI) and average daily gain(ADG) of piglets from d 1 to 35, damaged the cardiac tissue and liver on d 35, and decreased white blood cell counts(WBC), activities of catalase(CAT) and GSH-Px, and concentrations of glucose(GLU) and urea nitrogen(BUN) in the blood of piglets on d 70(P0.05). In addition, diets with 5 000 mg kg~(–1) saccharicterpenin supplementation reduced ADFI, ADG and increased diarrhea rates of piglets from d 36 to 70, and decreased hemoglobin(HGB) concentration and activity of CAT in the blood of piglets on d 70(P0.05). Moreover, at a rate of 5 000 mg kg~(–1), saccharicterpenin supplementation increased pancreas index on d 35 and hepatic index on d 70, and damaged cardiac tissue, liver and spleen during the whole experimental period(P0.05). These results suggested that dietary 500 mg kg~(–1) saccharicterpenin supplementation had beneficial effects on piglets, but excessive supplementation(2 500 or 5 000 mg kg~(–1)) of saccharicterpenin in the diets could lead to growth retardation, hematological abnormalities and organ injuries.  相似文献   

19.
【目的】研究散栏饲养和去势对荷斯坦奶公牛生长性能和血液生化指标影响,为公牛的科学育肥提供依据。【方法】选用26头健康、膘情正常、体重相近的荷斯坦奶公牛,对其进行去势处理,术后20d进行试验。再随机选取不去势的奶公牛26头,将去势与不去势的奶公牛随机各分为2组,各组试验初始体重基本相同(270kg左右)。试验共4组,每组13个重复,每个重复1头牛。I组为公牛散栏饲养;II组为公牛拴系饲养;III组为阉牛散栏饲养;IV组为阉牛拴系饲养。试验期206 d。【结果】(1)散栏饲养组日增重较拴系饲养组提高了13.59%(P0.01),公牛组日增重较阉牛组提高了13.59%(P0.01)。是否散栏饲养(FOT)和是否去势(NOC)的交互作用对平均日增重(ADG)有显著影响(P0.05),I组ADG较II组、III组和IV组分别提高了5.26%(P0.05)、5.26%(P0.05)和31.87%(P0.01);(2)散栏饲养组日粮中性洗涤纤维(NDF)和钙(Ca)表观消化率均极显著高于拴系饲养组(P0.01),粗脂肪(EE)和磷(P)表观消化率均显著高于拴饲养系组(P0.05)。公牛组日粮Ca表观消化率极显著高于阉牛组(P0.01);(3)散栏饲养组血清总蛋白(TP)、白蛋白(ALB)、谷草转氨酶(AST)、甘油三酯(TG)、总胆固醇(TC)和甲状腺原氨酸(T_3)均极显著高于拴系组(P0.01),谷丙转氨酶(ALT)、溶菌酶(LYS)和一氧化氮(NO)均显著高于拴系组(P0.05),尿素氮(BUN)极显著低于拴系组(P0.01)。公牛组血清TP、AST、GH、T_3、T和Ig G均极显著高于阉牛组(P0.01),TG、TC和瘦素(LP)均极显著低于阉牛组(P0.01),BUN显著低于阉牛组(P0.05)。FOT×NOC交互作用对TP、TG、TC和T3影响极显著(P0.01),其中I组TP、T_3最高,III组TG、TC最高。【结论】不去势散栏饲养模式可以提高奶公牛的育肥性能和免疫功能,去势散栏饲养模式可以提高奶公牛体内脂肪沉积量。因此,如果生产普通牛肉,建议270—500 kg阶段奶公牛育肥应选用不去势散栏饲养模式进行育肥;如果生产高档牛肉可选用去势散栏饲养模式进行育肥。  相似文献   

20.
Eight Chinese Holstein cows were used in a 4 × 4 Latin square design to determine the effects of rumen protected methionine (RPMet) and Niacin on milk yield and milk composition of lactating cows with 14 d adaptation and 6-d sampling periods. The cows were fed the control diet or the control diet plus RPMet (25 g·−1), niacin (6 g·−1), or RPMet (25 g·−1) + niacin (6 g·−1). The results showed that RPMet supplementation in the diet increased 4% fat corrected milk (FCM) yield (P < 0.05) and milk fat percentage (P < 0.05). However, supplemental RPMet had no effect on the solid non fat (SNF) (P > 0.05) and lactose percentage (P > 0.05). Dietary niacin supplementation increased milk yield (P < 0.05), milk protein percentage (P < 0.05) and lactose percentage (P < 0.05), but had no effect on milk fat percentage (P > 0.05) and SNF (P > 0.05). RPMet supplementation in the diet of lactating cows significantly decreased serum urea nitrogen (P < 0.01) and glucose contents (P < 0.05), but had no effects on nonesterified fatty acids (NEFA), total cholesterol and triglyceride (P > 0.05). Niacin supplementation influenced the contents of glucose and NEFA in serum, but had no effects on the urea nitrogen, total cholesterol and triglyceride (P > 0.05).  相似文献   

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