Thermal characteristics of Metarhizium anisopliae isolates important for the development of biological pesticides for the control of cattle ticks

Experiments were conducted to determine if Metarhizium anisopliae isolates which are capable of growth at cattle surface temperatures could produce pathogenicity to Boophilus microplus in laboratory and field studies. The diurnal temperature fluctuation on the surface of cattle was monitored. The temperature tolerance of M. anisopliae isolates (ARSEF3297 and IMI386697) was determined and their pathogenicity to B. microplus compared at a standard bioassay temperature (28 degrees C) and at a temperature similar to the cattle surface (31-35 degrees C). The effect of the two isolates on the B. microplus population on cattle under field conditions was determined. The temperature of the fore udder, rear udder, ribs and neck regions of the mixed Holstein cattle fluctuated between 30 and 35 degrees C, in a similar pattern to the prevailing environmental temperature. However, wider fluctuations were obtained on the ears (28-35 degrees C) and spine (30-41 degrees C). The colony radius of both isolates declined as temperature increased, however, the growth of IMI386697 was five times greater than ARSEF3297 at 34 degrees C. At 28 degrees C, the pathogenicity of both isolates to B. microplus was similar, however, at 31-35 degrees C, IMI386697 was more pathogenic than ARSEF3297. Both isolates reduced the B. microplus population on cattle in comparison to the control formulation. However, IMI386697 (8.5+/-0.64 ticks/animal) produced a greater reduction in tick numbers than ARSEF3297 (19.1+/-0.64 ticks/animal). M. anisopliae was re-isolated from 8.9% of the ticks collected from IMI386697 treated cattle as compared to 2.8% of ticks from ARSEF3297 treated cattle.     

Control of introduced mammalian predators improves kaka Nestor meridionalis breeding success: reversing the decline of a threatened New Zealand parrot

The kaka (Nestor meridionalis) is a threatened, endemic New Zealand parrot that is declining primarily because of predation by introduced mammals. Numbers of female kaka surviving to sexual maturity more than compensated for adult female mortality at three sites with predator control but not at three unmanaged sites. Nesting success at the sites with predator control was significantly greater (?80%) than at unmanaged sites (?38%) while predation on adult females was significantly less (5% c.f. 65%). Predation was the most common cause of nesting failure at all sites. Stoats (Mustela erminea) appeared to be the main predator, although evidence of possum (Trichosurus vulpecula) predation on eggs, nestlings and nesting females was also found. These results suggest that control of stoats and possums can potentially reverse the decline of the kaka on the main islands of New Zealand.     

Influence of Pre-Drying Treatments on Physico-Chemical and Phytochemical Potential of Dried mahua Flowers

Plant Foods for Human Nutrition - Mahua (Madhuca longifolia) flowers are boon for the local tribes of India and have been successfully utilized traditionally for the value addition, and are very...     

Monitoring long‐term changes in UK grey seal pup production

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Modelling the population size and dynamics of the British grey seal

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几种菊科植物杀菌活性的初步研究

以小麦赤霉病菌 (Gibberella zeae (schw.) Petch)、番茄灰霉病菌 (Botrytis cirerea Pers et Tris)、辣椒疫霉病菌 (Phytophthora capsici L eon)、苹果炭疽病菌 (Glomerella cingulata )、玉米大斑病菌 (Exserohilum turci-cum L eonard) 5种病原真菌为供试菌种 ,对菊科 15属 2 5种植物的丙酮提取液进行抑菌活性筛选。结果表明 ,除蒙山莴苣和千里光 2种植物外 ,其他 2 3种植物的提取液对至少 1种供试菌种有 6 0 %以上的抑制作用。臭蒿、大花金挖耳、猪毛蒿 3种植物提取液对 5种供试菌种的菌丝生长抑制率大于 70 %;大花金挖耳、猪毛蒿、天明精、苍耳、蓼子朴等 5种植物样品对 5种供试菌种的孢子萌发抑制率大于 93%;尤其是大花金挖耳、猪毛蒿 2种植物样品的提取液对 5种供试菌种的菌丝生长和孢子萌发的抑制率均大于 70 %,值得进一步研究开发。     

用低KOH溶解度加拿大双低菜粕部分替代TMR日粮中豆粕对泌乳早期奶牛产奶量和奶成分的影响

中国是世界上最大的油菜籽生产国，近几年来每年的生产量在1100万～1200万t（Huang等，2005；Deng，2005等）。这就意味着每年有600万～700万t的菜粕和菜饼产量。普通菜粕常常被作为水产饲料的原料（10％～40％添加），但是在猪、鸡、肉牛和奶牛日粮中常常被限制利用。这主要是由于普通菜粕中高含量的硫代葡糖苷（40～180μmol／g）及其衍生产物（异硫氰酸酯和恶唑烷硫酮）影响适口性所导致。     

Localization of the initial developmental stages of Loma salmonae in rainbow trout (Oncorhynchus mykiss)

The intracellular microsporidian parasite Loma salmonae affects salmonids of the genus Oncorhynchus and is a significant cause of economic losses in pen-reared Chinook salmon (O. tshawytscha) in British Columbia. Loma salmonae infection is easily recognized by the xenomas that form in the gills, but early stages of infection are difficult to detect in histologic sections. In situ hybridization (ISH), using an L. salmonae-specific digoxigenin-labeled single-stranded DNA probe, was used to detect the parasite during the early stages of infection. Loma salmonae was detected in the gut mucosal epithelium as early as 24 hours postexposure (PE), and it localized in the lamina propria of the intestine within 24 hours of infection. After the parasite was detected in the lamina propria, dividing merogonic stages in infected cells in the heart were detected by ISH as early as 2 days PE, providing the first evidence of parasitaemia and hematogenous distribution of this parasite in infected blood cells. The parasites inside the infected cells appeared to be undergoing merogony as they passed through the heart, indicating that proliferation may start at the site of infection, before the parasite arrives to the gills for their final developmental phase. This is the first time that L. salmonae passage through the intestinal wall and migration to the heart has been visualized; however, the identity of the cells harboring the parasite has yet to be determined.