Sequestration of PDC‐109 Protein by Specific Antibodies and Egg Yolk Cryoprotects Bull Spermatozoa

PDC‐109, one of the most abundant proteins in bovine seminal plasma, has detrimental effect on spermatozoa in a time‐ and concentration‐dependent manner. Therefore, we hypothesized that sequestration of detrimental protein from ejaculates would be beneficial following cryopreservation of sperm cells. To this aim, we evaluated the effect of sequestration of PDC‐109 either by anti‐PDC‐109 antibodies (Ab) or egg yolk (EY) alone or by the synergistic action of EY + Ab in minimizing cryoinjury to bull spermatozoa. PDC‐109 protein was purified by applying two‐step chromatography procedures. The purified protein was injected in rabbits to raise antibodies which were isolated using ion‐exchange chromatography. After checking the Ab cross‐reactivity, they were quantitated and added to ejaculates, either alone or in addition to EY in Tris‐glycerol (TG) extender. Thus, ejaculates were processed in extender containing EY + TG (group I), Ab + TG (group II) or EY + Ab + TG (group III). Semen quality parameters (SQPs) viz. viability and acrosome integrity (FITC‐PSA), cryoinjury to spermatozoa (chlortetracycline, CTC assay) and in vitro fertility of protein‐sequestered‐semen (zona‐penetration assay) were evaluated. A significant (p < 0.05) improvement in post‐thaw SQPs as well as in non‐capacitated spermatozoa observed at pre‐freeze and post‐thaw stages of cryopreservation in group III compared with other groups indicated reduction in protein‐mediated cryoinjury. From this study, it can be concluded that sequestration of PDC‐109 by synergistic action of EY+Ab as compared to either of them alone significantly improve sperm quality and minimize cryoinjury to bull spermatozoa upon storage at ultra‐low temperatures.     

促进竹房屋系统及近期发展

竹房屋系统的建造与实用建筑的方法有很大的区别。（1）原竹的利用和构架橡子作为主要的承载元素。（2）劈蔑竹和竹片胶合作为剪切壁，它能起到透风的作用，并能为其结构提供整体的稳定性；（3）根据危害和公共条件的程度作适当的竹子防腐处理;（4）在屋顶结构上，用于承载的接合点与软钢螺丝相结用于竹子的三角架;（5）竹席皱纹片用于顶部的包层。根据房屋的设计、内部的修饰和当地的条件，建造房屋时可采用低成本，在印度,每张板的价格为300～500卢比／m^2。为了改进技术，印度胶合板工业研究与培训所近几年修建了几个样板建筑。活动房的具体建筑、创新理念以及观点在本文进行了阐述。     

Impact of in-season split application of nitrogen on intra-panicle grain dynamics,grain quality,and vegetative indices that govern nitrogen use efficiency in sorghum

Background

The correct rate and timing of nitrogen (N) has the potential to improve sorghum productivity through modified grain yield components and quality. The impacts of in-season split application of N have little documentation.

Aim

An experiment was conducted to determine the optimum rate and timing of N to relate vegetative indices that govern nitrogen use efficiency and to maximize grain yield and quality under different soil types.

Methods

Pioneer 86P20 was grown in three environments on two different soil types following a completely randomized block design with nine N application treatments. Treatments included differing N rates applied at critical developmental stages of sorghum (planting, panicle initiation, and booting), accompanied with high temporal aerial phenotyping.

Results

Opportunities to increase grain protein content while using split N applications were observed, with panicle initiation identified as a critical developmental stage. In-season split application of N enhances grain yield under low soil mineral N. Split application of 31 kg N ha⁻¹ each at the time of planting, panicle initiation, and booting emerged as optimum N treatment to increase protein content in sorghum. Vegetative indices, that is, normalized difference vegetation index and normalized difference red edge index are capable of predicting grain yield and protein content, respectively. Intra-panicle grain numbers and weights were altered significantly at different portions within panicles, with an opportunity to enhance yield potential at the bottom portion. The strong stay-green trait in this hybrid locked a large proportion of nitrogen in the leaves, which warrants the need for balancing stay-green and senescence in sorghum improvement programs.

Conclusions

Findings highlight that in grain sorghum remobilization of residual leaf N into grain is a target to increase yield and grain quality. An optimized stay-green trait balanced with senescence is recommended for enhancing sorghum yield potential.     

Mapping quantitative trait loci associated with grain filling duration and grain number under terminal heat stress in bread wheat (Triticum aestivum L.)

Terminal heat stress has the potential negative impact on wheat production across the world, especially in South Asia. Under the threat of terminal heat stress, wheat genotypes with stay green trait would suffer from high temperature stress during their long grain filling duration (GFD). The genotypes with short GFD would be advantageous. To identify quantitative trait loci (QTL) for heat tolerance, a RIL population of K 7903 (heat tolerant) and RAJ 4014 (heat sensitive) wheat genotypes was investigated under timely and late‐sown conditions. Heat susceptibility index of GFD, yield components and traits under late‐sown condition were used as phenotypic data for QTL identification. Stable QTLs associated with these traits were identified on chromosomes 1B, 2B, 3B, 5A and 6B. The LOD value ranged from 2.9 to 5.0 and the corresponding phenotyping variation explained ranged from 12.0–22%. QTL for heat susceptibility index for the grain filling duration were colocalized with QTL for productive tillers under late sown and GFD under late‐sown condition on chromosomes 1B and 5A, respectively. These genomic regions could be exploited for molecular wheat breeding programmes targeting heat tolerance.     

Epidemiological investigation of the buller steer syndrome (riding behaviour) in a western Canadian feedlot

Objective To describe the buller steer syndrome in a Western Canadian feedlot. Design A retrospective epidemiological study. Animals 78,445 male cattle that entered a 24,000-head feedlot in western Canada from 1991 to 1993. Procedure All cattle were given a hormonal growth promotant containing 20 mg oestradiol benzoate and 200 mg progesterone within 24 h of arrival at the feedlot. A ‘buller’ was a steer that was observed at daily pen checking to be ridden persistently by pen mates or had evidence of having been persistently ridden by pen mates. At the completion of the feeding period, animal health records for bullers were collected and analysed. Results The prevalence of bullers in the total population was 2139/78,445 (2.7%, range per pen 0 to 11.2%). The prevalence of bullers increased with increasing weight and age. The relapse risk after first treatment (three days in the feedlot hospital plus treatment for concurrent disease) was 30% on average (27 to 35%). Individual records from 9734 yearling steers that entered the feedlot in 1991 and 1992 showed that bullers were significantly (P < 0.05) heavier at processing than non-bullers. Bullers occurred as a point source epidemic with the cause occurring soon after cattle arrived at the feedlot and were mingled into pen groups. This gave a ‘days on feed’ distribution. The peak incidence of bullers occurred much sooner after arrival and dropped off much quicker in older cattle. The daily incidence of bullers was temporal, but was not related to season of the year, weather conditions or any other feedlot management practice. It was related to the seasonal arrival of cattle at the feedlot, their age at entry to the feedlot and the post arrival occurrence of bullers. Reimplantation with hormonal growth promotants and castration of intact bulls did not produce an epidemic of bullers. Conclusion The findings of this study support the theory that bullers are the result of agonistic interactions, which occur concurrent with the establishment and maintenance of a social hierarchy within pens of feedlot cattle.     

Evaluation of insecticides against aphids (Myzus persicae Sulzer) and caterpillars (spodoptera litura [f.]) on tobacco in Karnataka State (India)

0.02% a.i. dicrotophos and dimethoate, 0.025% a.i. demeton-S-methyl, thiometon, chlorfenvinphos and methomyl, and 0.03% a.i. phosphamidon were evaluated in the field for control of aphids (Myzus persicae Sulzer) infesting tobacco. All the insecticides were effective but chlorfenvinphos and methomyl were inferior to the rest. 0.03% and 0.06% a.i. endosulfan and trichlorfon, 0.05% and 0.1% a.i. carbaryl, and 0.025% and 0.05% a.i. methomyl were evaluated in the field for control of caterpillars ofSpodoptera litura (F.) defoliating tobacco. Nearly all the insecticides were effective and carbaryl and trichlorfon gave satisfactory control even at the lower concentrations tested.