鸡胚胎期糖酵解关键酶mRNA的动态变化规律

在白色莱航鸡孵化第13d~21d期间,每天随机选取7个-8个胚胎,从中随机选取3个胚胎,分别采肝脏和骨骼肌样品(n=3),用Primer Express2.0(Applied Biosystem)和BLAST(NCBI)软件设计引物,从采取的肝脏和骨骼肌样品中分离出总RNA,采用反转录聚合酶链式反应(RT-PCR)法,合成cDNA。并应用限制性内切酶产物琼脂糖凝胶电泳法和核酸序列分析法对其进行同源性分析和鉴定目的片段。分别对其肝脏和骨骼肌中葡萄糖激酶、己糖激酶-I和己糖激酶-II的mRNA进行定量分析,旨在了解鸡胚胎发育过程中糖酵解关键酶的mRNA表达规律。结果表明:在孵化期的第13d~21d,鸡胚胎肝脏中葡萄糖激酶、己糖激酶-I和己糖激酶-II的mRNA含量均高于骨骼肌中的含量,但差异不显著(p>0.05)。孵化第17d时肝脏中葡萄糖激酶mRNA的含量明显减少(p<0.05),之后缓慢增加,到第21d时其含量仍低于第13d~15d时的含量;肝脏中己糖激酶-I mRNA在孵化第15d明显减少,之后缓慢增加,到孵化第19d时与第13d的含量接近;在孵化第13d~17d期间,肝脏中己糖激酶-II mRNA含量基本没有变化,到孵化第19d时略有升高,但差异均无显著(p>0.05)。骨骼肌中的3个关键酶的mRNA表达,在整个胚胎发育期均无明显的变化(p>0.05)。     

ROC analysis of prepartum feeding time can accurately predict postpartum metritis development in HF crossbred cows

Receiver operating characteristic (ROC) analysis is a useful statistical tool to visualize, organize, and select diagnostic variables. Accuracy of the test is represented by the area under the ROC curve (AUC), sensitivity (Se), and specificity (Sp). In the present study, ROC analysis of prepartum feeding time (day ?11 to day ?2) of 20 pluriparous Holstein-Friesian crossbred cows were recorded, and the cows were followed up for detecting postpartum metritis development if any. Prepartum daily feeding time data during whole study was grouped into 2 periods (P1 [day ?11 to day ?7] and P2 [day ?6 to day ?2]). The AUC of feeding time for the P1 and P2 periods was 0.64 (P = 0.29) and 0.86 (P = 0.006), respectively. Cows with daily feeding times below the optimum threshold value of 284.5 min/d during P2 (Se = 75% and Sp = 91.67%) had more chance of developing postpartum metritis compared with those with daily feeding time above the threshold value (positive likelihood ratio = 9.0). Furthermore, relative risk (RR) analysis revealed that the risk of development of postpartum metritis increased as feeding time decreased below the optimum threshold value during P2 (RR = 5.571, P = 0.004). Thus, the optimum threshold value of feeding time during P2 may be used to predict risk of postpartum metritis, allowing for preventive measures to be implemented in the early postpartum period to reduce the likelihood of postpartum complications.     

Ambrosia fungi: extent of specificity to ambrosia beetles

Experiments with developing ambrosia beetles and fungi indicate that beetles may feed on more than one species growing in their tunnels. The yeast-like ambrosia propagules in mycangia of beetles arise from conida and ascospores picked up by callow adults during their stay in tunnels.     

Renewable chemical commodity feedstocks from integrated catalytic processing of pyrolysis oils

Fast pyrolysis of lignocellulosic biomass produces a renewable liquid fuel called pyrolysis oil that is the cheapest liquid fuel produced from biomass today. Here we show that pyrolysis oils can be converted into industrial commodity chemical feedstocks using an integrated catalytic approach that combines hydroprocessing with zeolite catalysis. The hydroprocessing increases the intrinsic hydrogen content of the pyrolysis oil, producing polyols and alcohols. The zeolite catalyst then converts these hydrogenated products into light olefins and aromatic hydrocarbons in a yield as much as three times higher than that produced with the pure pyrolysis oil. The yield of aromatic hydrocarbons and light olefins from the biomass conversion over zeolite is proportional to the intrinsic amount of hydrogen added to the biomass feedstock during hydroprocessing. The total product yield can be adjusted depending on market values of the chemical feedstocks and the relative prices of the hydrogen and biomass.     

Reproduction in three genetic lines of dairy cattle housed a total confinement system.

Dairy cattle of three genetic lines maintained year round in total confinement (either in loose housing or tie stall barn) were monitored for estrous cycle activity and reproductive performance. Only 54% of the 492 cows calving over a 12 month interval were observed in estrus at least once between parturition and day 55 postpartum. There was a significant genetic line by barn interaction in the detection of estrus mainly because more cows of the Ayrshire line were observed in estrus in the tie stall barn (75%) compared to cows of the same line in the loose housing barn (48%). Month of calving had no effect on the subsequent detection of estrus. Conceptions to either first, second, third or fourth and greater services were 43, 44, 43 and 37%, respectively. Cows housed in the loose housing barn had significantly more days open than cows in the tie stall barn. Season of calving had no effect on the subsequent reproductive performance. Failure to detect estrus was the major problem for not obtaining a 12 month calving interval.     

Comparative biology of citrus leaf-miner on different citrus rootstocks and wild hosts

The oviposition by the citrus leaf-miner, Phyllocnistis citrella, was highest on ‘Rangpur’ lime and slightly lower on ‘Jatti Khatti’ and ‘Kharna Khatta’. ‘Cleopatra’ and ‘Troyer’ were moderately preferred, while the lowest number of eggs was recorded on Murraya exotica, followed by Jasminum sambac, but no mining was observed on these two hosts. The mean duration of the egg stage did not vary much on different hosts. The larval duration was highest in ‘Troyer’, indicating prolongation which was possibly due to antibiosis. The minimum larval survival was also recorded in ‘Troyer’, confirming antibiosis. There was not much difference in the pre-pupal stage. The pupal period was prolonged on ‘Troyer’ as compared to other hosts. This further confirms the occurrence of antibiosis in ‘Troyer’ to citrus leaf-miner. In general, the life cycle was short during June and long during February in all the hosts. The general conclusion is that ‘Troyer’ was a less suitable host for citrus leaf-miner compared to other rootstocks.     

A Review on Heavy Metal Ions and Dye Adsorption from Water by Agricultural Solid Waste Adsorbents

Agricultural solid wastes either in natural or in modified forms have been successfully used for decades as non-conventional cost-effective adsorbents for removing metal ions and dyes from their aqueous phase and have been recognized as a sustainable solution for wastewater treatment. Therefore, this review article provides extensive literature information about heavy metals and dyes, their classifications and toxicity, various treatment methods with emphasis on adsorption characteristics by numerous agricultural solid wastes, or agricultural solid waste-derived adsorbents under various physicochemical process conditions. This review article not only provided an up-to-date information on the application of sustainable low-cost alternative adsorbents such as agricultural solid wastes, agricultural by-products, and biomass-based cost-effective activated carbon and various other natural materials in the batch adsorptive removal of heavy metal and dye from aqueous phase but also presented a comprehensive compilation of adsorptive pollutant removal information based on various reported continuous column operation studies which is one of the new aspect to this review article. The effectiveness of various batch and column operational process parameters on mechanistic adsorptive removal of both heavy metals and dyes by various agricultural solid waste-based adsorbents has been critically discussed here. Batch and column adsorption mechanism, batch kinetics, column dynamic modeling, and adsorptive behavior of adsorbents under various process parameters have also been critically analyzed and compared. Finally, literature information on recovery and regeneration through desorption techniques and cost comparison of various agricultural solid waste adsorbents with commercial activated carbons have also been reported here. Conclusions have been drawn from the literature reviewed, and few suggestions for future research direction are proposed.     

Microbial biomass turnover and enzyme activities following the application of farmyard manure to field soils with and without previous long-term applications

Summary We studied the build-up and turnover of microbial biomass following the addition of farmyard manure to an unmanured soil and to soils from a long-term experiment in which different levels of farmyard manure had been applied for the last 23 years. The application of farmyard manure at 15–90 t ha^-1 to previously unmanured soil increased the microbial biomass during the first 3 months of incubation but a gradual decline occurred with further incubation for up to 12 months. Microbial biomass C was positively correlated with soil organic C and ranged from 1.8% to 2.2% of organic C after 12 months of farmyard manure applications. Biomass turnover increased with the application of farmyard manure, ranging from 0.81 to 0.87 year^-1 with various levels of manure. Amendment of soils from the long-term manure experiment with various levels of farmyard manure led to a build-up and decline in biomass C as seen in the unmanured soils, but biomass C was higher in all treatments compared to the corresponding unmanured soil treatments. Biomass turnover was greater compared to the unmanured soil treatments and it decreased with increasing levels of farmyard manure. The average soil respiratory activity increased with increasing levels of farmyard manure, but respiratory activity per unit of biomass C decreased with increasing levels of manure. Enzyme activities were greater in long-term manured soils compared to unmanured soils amended with various levels of manure. There was a significant correlation between biomass C and enzyme activities.     

Effect of lameness (hoof disorders) on productivity of Karan Fries crossbred cows

In present study production performance of 96 lame cows was compared with 67 healthy cows. No significant effect of parity and year of calving on milk yield were observed but the effect of season of calving was significant (P < 0.01). Effect of lameness on milk yield at the second, third and fourth months and 305 days was highly significant (P < 0.01), and was also significant (P < 0.05) on lactation yield of the fifth and tenth months. The effect of lameness on monthly and 305‐day milk yield was significant (P < 0.01) only for those cows diagnosed lame before calving and during the first month of lactation. The differences in mean monthly yield were highly significant (P < 0.01) at the second, third and fourth months; and significant (P < 0.05) in the first and fifth months. The loss in the first lactation month of cows which were diagnosed as lame in the second month, was found to be significant (P < 0.05). Thus the yield of the month previous to the diagnosis (sub‐clinical stage) was also affected. A significant (P < 0.01) total loss of 498.95 kg of milk yield was observed during a period of 305 days.