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991.
992.
This experiment evaluated the effects of subnutrition during early gestation on hematology in cows (Bos Taurus) and on hematological, metabolic, endocrine, and vitality parameters in their calves. Parda de Montaña and Pirenaica dams were inseminated and assigned to either a control (CONTROL, 100% requirements) or a nutrient‐restricted group (SUBNUT, 65%) during the first third of gestation. Dam blood samples were collected on days 20 and 253 of gestation, and calf samples were obtained during the first days of life. Pirenaica dams presented higher red series parameters than Parda de Montaña dams, both in the first and the last months of gestation. During early pregnancy, granulocyte numbers and mean corpuscular hemoglobin were lower in Pirenaica‐SUBNUT than in Pirenaica‐CONTROL cows. Calves from the SUBNUT cows did not show a physiological reduction in red series values in early life, suggesting later maturation of the hematopoietic system. Poor maternal nutrition affected calf endocrine parameters. Newborns from dystocic parturitions showed lower NEFA concentrations and weaker vitality responses. In conclusion, maternal nutrition had short‐term effects on cow hematology, Pirenaica cows showing a higher susceptibility to undernutrition; and a long‐term effect on their offspring endocrinology, SUBNUT newborns showing lower levels of IGF‐1 and higher levels of cortisol.  相似文献   
993.
994.
995.
为了明确莠去津土壤残留对后茬蔬菜的影响,在室内采用毒土添加法研究了莠去津不同土壤残留量对黄瓜、豇豆、辣椒和菜薹光合作用和幼苗生长的影响。结果表明:莠去津土壤残留量为0.21、1.84、0.24、0.11 mg·kg~(-1)时,导致黄瓜、豇豆、辣椒和菜薹叶片PSⅡ最大光化学效率(Fv/Fm)下降10%;4种蔬菜分别在接近此有效成分剂量时(黄瓜0.2mg·kg~(-1)、豇豆2 mg·kg~(-1)、辣椒0.2 mg·kg~(-1)、菜薹0.1 mg·kg~(-1)),电子传递速率(ETRⅡ)显著下降,且单株鲜质量抑制率达到50%;4种蔬菜对莠去津土壤残留的敏感性顺序为:菜薹黄瓜辣椒豇豆;Fv/Fm可作为早期预知轮作蔬菜是否受到莠去津残留潜在药害的指标,Fv/Fm的ID_(10)为轮作蔬菜是否受药害的临界值。  相似文献   
996.
籽粒品质性状的遗传参数分析,可以为优良品质的玉米新品种选育提供依据。本研究以10个玉米组合为材料,利用R软件的混合线性模型,获取不同取样时期每个基因型的最佳线性无偏预测值(Best linear unbiased prediction, BLUP),进行籽粒品质相关性状遗传参数分析。结果表明,BLUP数据更接近于真实育种值。不同取样时期,品质性状的变异系数变化较大,籽粒品质性状的最大变化发生在S3(9月14日)到S4(9月18日)时期,此时玉米正由蜡熟期进入完熟期。对各品质性状间的相关性进行分析,粗脂肪与粗蛋白、氨基酸均存在显著或极显著正相关。水分、粗蛋白、粗脂肪、粗淀粉、氨基酸含量均属于高遗传力性状,其中,粗淀粉的遗传力最高,达0.887,容重属于中等遗传力性状。  相似文献   
997.
A 30‐day experiment was performed to determine the effect of pigeon pea leaves (PPL) on growth performance, carcass trait, meat quality, nutrient digestibility, antioxidant capacity and biochemical parameters of growing rabbits. In a completely randomized design, PPL replaced alfalfa meal at the level of 0%, 10%, 20% and 30%, which were named PPL0 (control), PPL10, PPL20 and PML30 respectively. Two hundred New Zealand white rabbits at 6 weeks with similar weight (870.23 ± 15.98 g) were allocated to four dietary groups with five replicates containing 10 rabbits/per replicate (male). The results showed that: (a) PPL powder contained 24.26% crude protein, 4.34% crude fat, 17.86% crude fibre, 7.05% ash, 1.35% calcium, 0.28% phosphorus, 1.09% lysine and 0.20% methionine, and the chemical compositions are on DM basis; (b) the ratio of feed to gain of rabbits fed diet PPL10 was significantly better (p < 0.05) than those fed other three diets; (c) the content of longissimus dorsi (LD) moisture in the rabbits fed diets without PPL (control group) was 12% lower than that in the PPL30 diets (60.1 vs. 72.1; p < 0.05). In PPL10, PPL20 and PPL30 diets, the leg muscle (LM) b*(yellowness) value was 33%, 30% and 22.6% higher than the control group respectively. The rabbits fed diets PPL0 had lower (p < 0.05) LM crude protein and ash and higher (p < 0.05) crude fat of LD and LM as compared with those fed other diets; (d) crude protein and energy digestibility of PPL0 and PPL10 diets were significantly higher (p < 0.05) than PPL30 diets; and (e) serum glutathione peroxidase (GSH‐Px) activity of the rabbits fed PPL10 and PPL30 diets was significantly higher (p < 0.05) than that fed PPL20 diets. Liver total antioxidant capacity (T‐AOC) activity of the PPL30 groups was 1.3% higher (p < 0.05) than the PPL10 group. Additionally, the control group (PPL0) had the highest (p < 0.05) blood urea nitrogen (BUN), total cholesterol (TCHO) and low‐density lipoprotein cholesterol (LDLC) content compared with the groups supplemented with PPL. The PPL30 group had the highest (p < 0.05) triiodothyronine (T3) and tetraiodothyroxine (T4) value among the dietary groups.  相似文献   
998.
In the United States, multistate Salmonella outbreaks are most commonly linked to a food source; however, contact with live animals can also result in outbreaks of human illness. To characterize Salmonella outbreaks linked to animal contact and examine differences compared to foodborne outbreaks, we analysed data reported to the Centers for Disease Control and Prevention through the National Outbreak Reporting System (NORS) from 2009 to 2014 with a primary mode of transmission listed as “animal contact” or “food.” Four hundred and eighty‐four outbreaks with animal contact or foodborne transmission were reported through NORS; of these outbreaks, 99 (20.5%) resulted from Salmonella transmission through animal contact and 385 (79.5%) resulted from foodborne transmission, which resulted in 3,604 (19.8%) and 13,568 (80.2%) illnesses, respectively. A higher proportion of illnesses among children aged <1 year and children aged 1–4 years were linked to animal contact outbreaks compared to foodborne outbreaks (15.2% vs. 1.4%, p < 0.01 and 24.5% vs. 5.6%, p < 0.01, respectively). Illnesses resulting in hospitalizations (OR: 1.81, 95% CI: 1.62, 2.02) were more likely to be associated with animal contact compared to food. Animal contact outbreaks reported to NORS were more likely to be multistate compared to foodborne outbreaks (OR: 5.43, 95% CI: 3.37, 8.76) and had a longer median duration (99.0 days vs. 9.0 days, p < 0.01). Characterizing the differences between outbreaks of illness linked to animal contact and outbreaks linked to food provides useful information to investigators to improve public health response.  相似文献   
999.
本试验旨在研究仔猪断奶1周内补饲液态复合饲料添加剂对其生长性能、养分消化率、消化道p H及血液指标的影响。挑选20日龄仔猪105头,断奶前屠宰5头,其他100头在21日龄断奶后分为对照组和试验组,每组5个重复,每个重复10头猪。对照组仔猪饲喂教槽料,试验组仔猪在每次饲喂教槽料后补喂液态复合饲料添加剂(主要成分为酸化剂、中药提取物、壳寡糖、复合离子调节剂)。试验从断奶当天至断奶后第8天,共计7 d。结果表明:试验组的平均日增重高于对照组(P0.05),腹泻率显著低于对照组(P0.05);试验组粗蛋白和钙的表观消化率较对照组显著增加(P0.05);试验组仔猪断奶后第2天和第8天胃部p H、断奶后第8天十二指肠p H、断奶后第4天回肠p H均显著低于对照组(P0.05),断奶后第4天氯离子含量、断奶后第2天和第8天球蛋白、断奶后第4天和第8天血清Ig G和Ig A含量均显著高于对照组(P0.05),而断奶后第2天血清尿素氮显著低于对照组(P0.05)。由此表明,断奶1周内给仔猪补饲液态复合饲料添加剂,可降低消化道p H,提高养分消化率,并改善机体免疫功能,从而提高仔猪断奶1周内的生长性能,降低仔猪腹泻率。  相似文献   
1000.
The aim was to elucidate the impact of Royal Jelly (RJ) on behavioural patterns, feather cover, egg quality and some blood haematological indices in laying hens (58–64 weeks of age). A total of 108 Tetra Brown laying hens were used in the current trial. The birds were divided into three equal groups (36 birds each). The pure RJ was prepared for immediate injection subcutaneously, as follows: the first treated group (RJ1:100 mg/kg); the second treated group (RJ2:200 mg/kg); the control group. The eating and drinking activities in the RJ2 group were significantly (p = .009 and .015 respectively) higher than the control and RJ1 groups. Furthermore, the aggressive pecks, feather pecks and threating behaviour in the RJ2 group were significantly (p = .005, .001 and .039 respectively) lower than the control and RJ1 groups. Both RJ‐treated groups had the best feather cover on the neck and abdomen regions (p = .010 and .001 respectively; Figure  1 ). Both RJ‐treated groups had a significantly higher eggshell ratio (p = .019) and shell thickness (p = .001) in comparison with the control group. The albumen height, Haugh units and yolk index in both RJ‐treated groups were significantly greater than those recorded in the control group (p = .026, .001 and .022 respectively). The erythrocyte and total leucocyte counts in the RJ2 group were significantly higher than those reported in the control and RJ1 groups (p = .029 and .013 respectively); however, the heterophil/lymphocyte (H/L) ratio and heterophil % in both RJ‐treated groups were significantly the lowest (p = .001 and .039). In conclusion, birds in the RJ2 group had superior feather cover, welfare and behavioural indices, probably due to the impact of active flavonoids components of RJ on laying hen performance. Furthermore, the RJ‐treated groups had significantly improved egg quality parameters and some blood haematological indices.  相似文献   
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