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31.
Forty female goats in the third parity were randomly divided into four similar groups. The experiment was started 20 days before mating and lasted until the end of the suckling period for 60 days and weaning their kids. The first group were fed diet without supplementation and kept as control while in the second, third and fourth groups, each doe was fed diets with rumen protected choline (RPC) at the rate of 10, 20 and 40 g/day, respectively. Results showed that number of doe kidding twins and triplets and litter weight of kids born per group increased with increasing the level of RPC in the diet of goats and viability rate of born kids during the suckling period improved due to RPC supplementation in the diets of their mothers. Duration of estrous, days from weaning to estrous, days from kidding to estrous and kidding interval decreased significantly, while conception rate increased due to adding RPC. Milk choline concentrations and total choline secretion though milk were progressively increased significantly with increasing the level of RPC supplementation. Live body weight and daily body gain of their suckling male and female kids at weaning increased significantly with increasing RPC levels in the diets of their mothers.  相似文献   
32.
The present research was designed to investigate the growth promoting and immunostimulating properties of Moringa oleferia leaf meal (MLM) in grass carp. Juvenile grass carp (22.03 g ± 1.164) were fed with diets supplemented with 0, 50, 100 and 150 g/kg MLM for 48 days. At the end of feeding trial, skin mucus was used for analysis of lysozyme, protease, antiprotease and peroxidase activity. Head kidney was used for expression analysis of tumour necrosis factor‐alpha, interleukin‐8 and interferon‐γ. The obtained results showed that fish fed with 100 and 150 g/kg MLM had significant increase in weight gain and specific growth rate (p < .05). However, condition factor was not altered. The MLM (50 and 100 g/kg) inclusion resulted in higher mucus lysozyme and protease activity (p < .05), while peroxidase activity increased only in fish fed with 100 g/kg MLM and antiprotease activity was not altered. Expression of tnf‐α increased in a dose‐dependent manner, and significant (p < .05) increase was recorded in fish fed with 150 g/kg MLM. The expression of il‐8 and ifn‐γ increased in fish fed with 50 and 150 g/kg MLM; however, the increase was not significant (p > .05). In conclusion, supplementing juvenile grass carp feed with MLM up to 150 g/kg has growth promoting and immunostimulating effects.  相似文献   
33.
In recent years, crayfish aquaculture industry has been developing rapidly in different regions of the world. Crayfish aquaculture is often carried out in dams, lakes and extensive pond systems. There is an increasing demand for crayfish juvenile in aquaculture sector. Therefore, it is important to know which factors affect reproductive efficiency in crayfish. In the present review, factors affecting the reproductive efficiency of crayfish are divided into two main sections, external and internal factors. Dietary lipids, phospholipids, highly unsaturated fatty acids, protein and amino acids, vitamins and carotenoids are important external factors affecting broodstock crayfish reproduction. In addition, various external (i.e. female size, stocking density, temperature, photoperiod, sex ratio) and internal (i.e. endogenous hormones) factors affect the reproductive efficiency in crayfish. This study reviews the present knowledge with the purpose of realizing the factors that are important to reach optimal crayfish nutrition, maturation and reproduction (i.e. pleopodal egg number and quality). This review will particularly be useful for crayfish farmers and crayfish hatchery units.  相似文献   
34.
If they could be easily exfoliated, layered materials would become a diverse source of two-dimensional crystals whose properties would be useful in applications ranging from electronics to energy storage. We show that layered compounds such as MoS(2), WS(2), MoSe(2), MoTe(2), TaSe(2), NbSe(2), NiTe(2), BN, and Bi(2)Te(3) can be efficiently dispersed in common solvents and can be deposited as individual flakes or formed into films. Electron microscopy strongly suggests that the material is exfoliated into individual layers. By blending this material with suspensions of other nanomaterials or polymer solutions, we can prepare hybrid dispersions or composites, which can be cast into films. We show that WS(2) and MoS(2) effectively reinforce polymers, whereas WS(2)/carbon nanotube hybrid films have high conductivity, leading to promising thermoelectric properties.  相似文献   
35.
The objective of this study was to determine the chemical composition and in vitro dry matter (IVDMD) and neutral detergent fibre (IVNDFD) digestibilities of silages made from whole‐crop pea [Pisum sativum L. (PS)], pea–wheat [Triticum aestivum L. (PW)], pea–barley [Hordeum vulgare L. (PB)] and pea–oat [Avena sativa L. (PO)] mixtures harvested 8 weeks (H8) and 10 weeks (H10) after seeding. Forty‐five days after ensiling, all forages were well ensiled as indicated by low pH and low water‐soluble carbohydrate content and high lactic acid concentration. Regardless of forage type, crude protein (CP) and IVNDFD were higher while starch and acid detergent lignin were lower in H8 than H10. However, harvest date had no effect on neutral (NDF) and acid (ADF) detergent fibre of the silages. Within each harvest date, CP was higher while NDF was lower for PS than pea–cereal silages. Differences in CP and fibre fractions between the pea–cereal mixture silages were not consistent for the two harvest dates. The IVDMD of PS was higher than that of the three pea–cereal mixture silages in H8 but was only higher than that of PB in H10. For the pea–cereal mixtures, IVDMD was higher for PO than PB and PW in H8 and was higher for PB than PW in H10. It was concluded that silage from pea monoculture had similar forage yields and a generally higher nutritive value than silages from pea–cereal mixtures.  相似文献   
36.
37.
The aim of this study was to evaluate prognostic and/or diagnostic factors of canine mammary tumors by immunohistochemically analyzing the expression of alpha basic crystallin (αB-c). For this, formalin-fixed, paraffin-embedded blocks of 51 naturally-occurring canine mammary tumors (11 benign and 40 malignant) were used. Tissue from eight normal canine mammary glands were served as a control. Immunohistochemically, in the control mammary tissues, a few luminal epithelial cells were αB-c positive but myoepithelial cells were negative. In benign or simple type malignant tumors, αB-c expression was observed in luminal epithelial cells while the myoepithelial basal cells were negative. In benign or complex type malign tumors, positive staining was predominantly found in the cytoplasm of epithelial cells. Immunoreactivity of αB-c was also observed in neoplastic myoepithelial cells. Statistically, the number of cells immunolabeled with αB-c was found to be significantly different among tissues from normal canine mammary glands, benign lesions, and malignant tumors (p < 0.05). αB-c immunoreactivity was higher in malignant tumors than the control mammary tissues (p < 0.001). Data obtained in the current study revealed a strong association between high expression levels of αB-c and primary mammary gland tumors in canines.  相似文献   
38.
Phyllo sheets were produced with flour obtained at different extraction rates (53, 58, or 67%), and stored at 4 and 25°C. Physical, chemical, and sensory properties of fresh and stored phyllo were researched. Fresh phyllo samples from wheat flour at 53% extraction rate were thinner (0.4 mm) and had whiter color (L* = 87.6). Textural properties and overall sensory acceptability of phyllo samples significantly decreased (P ≤ 0.01) with increased extraction rates and storage times. At the end of four days, toughness and extensibility decreased from 0.88 N and 10.9 mm to 0.65 N and 6.7 mm at 4°C and to 0.45 N and 5.6 mm at 25°C. The 53% extraction rate was more suitable for producing phyllo. The shelf life of phyllo samples for preparing borek was determined four days at 4°C and two days at 25°C according to acid contents and sensory properties.  相似文献   
39.
ABSTRACT

Soil erosion is a major socioeconomic and environmental problem in Turkey. Almost 86% of the land in Turkey has suffered various degrees of soil erosion. The objective of this study was to determine whether differences in tree species affect soil characteristics and microbial activity in degraded soils. Results from this study showed that organic C (Corg) was highest in the black locust soil at 0–20 cm depth and lowest in the bare land. Microbial biomass C (Cmic) increased in the order black locust > Scotch pine > bare land at two soil depths. One-way ANOVA demonstrated that afforested soils contain significantly higher microbial biomass C than those in the bare land soils. Microbial quotient (Cmic/Corg) of soils are positively influenced by afforestation as the bare land soils exhibited lower microbial quotient than the associated Scotch pine and black locust soils. Microbial communities in black locust soils were energetically more efficient—had a lower metabolic quotient (qCO2)—with a higher Cmic/Corg compared to those in Scotch pine soils. However, the microbial quotient in our study was still below range and cannot reach equilibrium again 15 yr after afforestation. Restoration of degraded lands could be a long-term process from microbial activity in the observed regions.  相似文献   
40.
A rhizobox experiment was conducted to compare the differences of soil potassium (K) distribution and absorption between two cotton (Gossypium hirsutum L.) genotypes under drought and K‐deficit conditions. Treatments included two levels of water (drought and optimum soil moisture: 25% and 35% volumetric water content) and K fertilizer rates (0 and 0.48 g potash kg?1 soil) applied to two cotton genotypes (namely HEG and LEG). Both the genotypes showed significant differences in total K accumulation without exogenous K addition. After absorption, soil content of the readily available potassium (RAK) decreased rapidly. This promoted the conversion of the mineral K into slowly available potassium (SAK). Drought significantly decreased the cotton growth and K use efficiency, and thereby reduced the effect of K fertilizer. Consequantly, the contents of RAK and SAK were greatly increased. However, K bioavailability was decreased under water stress conditions. Differences in root parameters and soil microorganisms between two cotton genotypes were significantly increased and had marked relations with available soil K contents. This study provides important information for understanding the mechanism of K use efficiency, especially under water and K stress.  相似文献   
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