60～90日龄不同性别腾冲雪鸡血液生化指标差异研究

 采集60～90 日龄腾冲雪鸡公母各8 只的静脉血,测定了血清中的血糖(GLU)、甘油三脂(Trig)、胆固醇(CHOL)、白蛋白(ALB)、总蛋白(TP)、尿酸(UA)、肌酐(CREA)、尿素氮(UN)、谷丙转胺酶(ALT)、谷草转胺酶(AST)、钙(Ca) 和无机磷(P) 等12个指标的含量。结果发现: 除甘油三脂和无机磷(P<0.05) 及尿酸(P<0.01)性别间有显着和极显着差异外,其余9项指标公母间差异不显着(P>0.05). 因而在测定腾冲雪鸡生化指标时,除性别间差异显着的指标应分别测定才能对其是否正常作出结论外,其余指标可不考虑性别差异。合并差异不显着的指标数据后,得它们的正常值分别为: 血糖(20.41±4.82)mmol/L;胆固醇(3.64±0.41)mmol/L; 白蛋白(16.19±2.29) g/L; 总蛋白(39.88±6.41)g/L; 肌酐(136.77±10.53)μmol/L; 尿素氮(0.54±0.22)mmol/L; 谷丙转胺酶(7.31±2.87)IU/L; 谷草转胺酶(331.87±74.16) IU/L和血钙(97.13±8.69)mg/L。应考虑公母性别正常值差异的指标有:甘油三脂公鸡为(0.24±0.10)mmol/L,母鸡为(0.15±0.04)mmol/L;尿酸公鸡为(257.25±86.8)μmol/L,母鸡为(124.88±55.12)mol/L;无机磷公鸡为(63.19±4.51)mg/L,母鸡为(57.36±5.92)mg/L虽然无机磷公母性别间差异显著,但其比值间差异并小显著(P>0.05),公鸡为1.59±0.25,母鸡为1.68±0.27同时也探讨了血清日油三脂和尿酸性别间存在差异的机理。     

Response of a desert lizard community to habitat degradation: Do ideas about habitat specialists/generalists hold?

We report the impact of human-induced desertification on the species richness, abundance, and composition of sand dune flora and herpetofauna of North Sinai, Egypt. Our hypothesis was that degraded habitats would have reduced vegetation complexity, richness, and abundance, and consequently lower reptile species richness and abundance. We also hypothesized that desert lizards would not follow the typical generalist/specialist responses to habitat degradation found in other biomes. Instead, we predicted that because vegetation loss intensifies the environmental extremity of deserts, those species specialized for open and sandy environments would be more likely to persist in desertified habitats than would desert generalists. Our results showed that areas protected from vegetation loss did not have significantly higher vegetation richness or abundance except for only a few species. However, protected sites did have significantly higher percent vegetation cover and height. Habitat protection clearly had strong effects on the reptile community as species richness and abundances were significantly higher in protected sites. The composition of the reptile community between protected and unprotected sites differed significantly. Contrary to past studies in other environments, desert generalist species were not able to persist in degraded sites and were only found in protected sites. Specialist species were ubiquitous in that they occurred in both areas protected and unprotected from vegetation loss. We propose that the effects of disturbance on species composition (specialists or generalists) depends on whether the disturbance exacerbates or reduces environmental harshness and the conditions that favor specialization. In extreme environments, specialist and generalist responses to habitat degradation are opposite to that of more productive environments.     

Response of Sunflower to Sulfur Rate and Time of Application under Two Tillage Systems in a Silty Clay Soil of Dera Ismail Khan Pakistan

ABSTRACT

Sulfur (S) availability is a characteristic of conservation tillage. We studied the effects of S on sunflower yield and fatty acid profile under conventional and conservation tillage in silty clay soil of D.I. Khan, Pakistan. Conventional tillage consisted of disk plowing followed by tiller and rotavator, while conservation tillage comprises tiller and disc harrowing. Treatments comprise six sulfur levels (S₁ = 0, S₂ = 20 kg S ha^?1 at sowing, S₃ = 10 kg S ha^?1 at sowing +10 kg S ha^?1 25 days after sowing (DAS), S₄ = 40 kg S ha^?1 at sowing, S₅ = 20 kg S ha^?1 at sowing + 20 kg S ha^?1 25 DAS, and S₆ = 20 kg S ha^?1 at sowing + 10 kg S ha^?1 25 DAS + 10 kg S ha^?1 50 DAS) replicated thrice. After 2 years of experimentation, soil samples were collected (from 0 to 0.30 m depth) for organic matter (OM), total soil N (TSN), and available sulfur analysis. Conservation tillage significantly increased OM, TSN, and S contents in 0–0.30 m soil compared to conventional tillage. Likewise, sunflower plants showed higher achene yield, better fatty acid profile, and net economic returns in conservation tillage than in conventional tillage. Application of 20 kg S ha^?1 at sowing and 10 kg S ha^?1 at each 25 and 50 DAS recorded significantly higher achene yield, higher oil, and linoleic acid contents; however, oleic and oleic/linoleic ratio did not increase with higher S rates. Conservation tillage was effective in increasing OM, TSN, and available S besides increasing yield and economics in silty clay soil.     

Enteric methane emissions of grazing short-horn zebu weaner bulls vary with estimation method and level of crude protein supplementation

Tropical Animal Health and Production - Low nutrient intake of short-horn zebu (SHZ) cattle raised under extensive grazing systems results in delayed attainment of mature market weights and...     

稻瘟病菌孢子对水稻叶表附着量的研究

针对叶稻瘟病侵染中的一个环节,通过疫区及室内模拟的多年试验,分别找出该病菌分生孢子稻田低空浮游量与田间前一天病情指数、20:00时温度、相对湿度、日照时数及当天最低温度的数学关系式;得出该浮游量与水稻叶表附着量的转换值;寻出不同生长阶段稻株单位叶面积病菌分生孢子的附着系数及各叶位叶片的附着率;并结合田间水稻叶面积情况组装该侵染环节的数学模型。     

杂交稻制种母本撒直播的花遇规律及成因研究

近年发现，杂交稻春、夏季制种母本撒直播比移栽的异交结实率高５％左右。经试验观察，父、母本日开花相遇机率提高３．５％，时开花相遇机率提高６．５％。前者由两亲本成穗结构相似所致，后者与母本撒直播的群体密度大、有效穗多、调节田间小气候使母本开花提早有关。     

粳系21—2特征特性及其栽培技术

粳系21—2一般亩产400公斤左右,在安徽省区试和生产试验中,平均比鄂宜105增产5.8%。全生育期125—130天,株高80～90厘米,株、叶形适中,分蘖力中等,生长清秀,熟色好。平均每穗70余粒,结实率85—90%,千粒重约25克,米质优良。对主要病害有一定的田间抗性。适宜在中等肥力条件下栽培。其适宜播期为6月18—25日,秧田播种量40—50公斤,秧龄30—35天。大田亩栽2.5—3.0万穴,基本苗15—20万。在肥力中等田块,亩需纯氮9公斤左右,适当搭配磷钾肥。以基肥为主,早施追肥,后期控制用氮。够苗及时烤田,后期不断水过早,并加强病虫预防。