Historical trends in the incidence of strandings of sperm whales (Physeter macrocephalus) on North Sea coasts: An association with positive temperature anomalies

Information on the migration patterns of sperm whales (Physeter macrocephalus) in the North Atlantic is preserved in historical strandings records, particularly for the North Sea, where sperm whale strandings have been documented since the 16th century, reflecting general public interest in large whales ashore. Most strandings in this area occur during or following the southward migration from the feeding grounds, when some animals enter the North Sea (in which they are thought to have difficulty navigating) instead of following their usual route through deep water to the west of the British Isles. There was much speculation about the causes of the high incidence of strandings on North Sea coasts in the 1990s, among which a recently published analysis of long-term trends in strandings indicated an effect of sunspot cycle length. We show that long-term interannual variation in the incidence of sperm whale strandings on North Sea coasts is related to positive temperature anomalies: the incidence of strandings was higher in warmer periods. The effect of temperature anomalies explains between 8 and 9% of variation in the strandings series. Inclusion of sunspot cycle length as an additional predictor did not significantly improve this model. It is suggested that this link with positive temperature anomalies may reflect changes in the distribution of the sperm whales’ main squid prey.     

The first survey and molecular identification of Entamoeba spp. in farm animals on Qinghai-Tibetan Plateau of China

Protozoans of Entamoeba spp. are globally distributed zoonotic parasites that infect diverse animal hosts and humans. Prevalence and species/genotypes distribution of Entamoeba spp. in domestic animals are not fully investigated on Qinghai-Tibetan Plateau (QTP), an animal husbandry and agriculture region of China. In a survey, 528 fecal samples were collected from 7 species of domestic animals on multiple locations across QTP region and analyzed by PCR and sequencing analysis. The overall prevalence of Entamoeba spp. infection in all examined animals was 97.9 %. Four Entamoeba species, E. bovis, E. moshkovskii, E. ecuadoriensis and E. histolytica were found, and majority (94.2 %) of Entamoeba-infected animals harbored E. bovis. Six Entamoeba genotypes, Entamoeba ribosomal lineages (RL) 1, 2, 3, 4, 8 and 9 were identified by sequencing analysis. Two zoonotic species, E. moshkovskii and E. histolytica, were present in horses, while E. ecuadoriensis and E. bovis were found in horses and all species of seven farm animals, respectively. It was also observed that six Entamoeba genotypes were distributed in animals in specific pattern. The results revealed high prevalence of Entamoeba spp. infection in livestock, broad range of hosts as well as diversity and species/genotype distribution of Entamoeba spp. in farm animals inhabiting on the high altitude QTP region.     

Sensitivity of Botryosphaeria dothidea from apple to tebuconazole in China

The white rot disease caused by Botryosphaeria dothidea threatens apple production in Bohai bay area and along the Yellow River of China, where disease control is largely dependent on fungicides such as tebuconazole. A total of 146 isolates of B. dothidea obtained from different apple orchards in six provinces were tested for their sensitivity to tebuconazole, carbendazim and iprodione. The EC₅₀ values of all tested isolates for tebuconazole were from 0.035 to 1.415 μg/mL. The broad range of EC₅₀ values of tebuconazole suggests an obvious variation among the 146 isolates. Isolate HB13 (EC₅₀ = 1.415 μg/mL) showed reduced sensitivity to tebuconazole, with an EC₅₀ value significantly higher than those of the other 145 isolates tested. The low sensitivity of HB13 was stable after 15 generations, and this isolate showed similar pathogenicity as susceptible strains. EC₅₀ correlation analysis indicates no cross resistance between tebuconazole and carbendazim and iprodione. Field efficacy trials showed that tebuconazole remains very effective for apple white rot control in China.     

Development of a vision-based automatic vaccine injection system for flatfish

Traditionally, flatfish vaccination has been performed manually a laborious and time-consuming, procedure with low accuracy. The handling requirement also makes it prone to contamination. With a view to eliminating these drawbacks, we designed an automatic vaccine system in which the injection is delivered by a Cartesian coordinate robot (also called a linear robot) guided by a vision system. The automatic vaccine injection system is driven by an injection site location algorithm that uses a template-matching technique. The proposed algorithm was designed to derive the time and possible angles of injection by comparing a search area with a template. The algorithm is able to vaccinate various sizes of flatfish, even when they are loaded at different angles. We validated the performance of the proposed algorithm by analyzing the injection error according to randomly generated loading angles. The proposed algorithm allowed an injection rate of 2000 per hour on average. Vaccination of flatfish with a body length of up to 500 mm was possible, even when the orientation of the fish was random. The injection errors in various sizes of flatfish were very small, ranging from 0 to 0.6 mm.     

链烷技术检测蝗虫食性方法的研究

为验证链烷技术测定蝗虫食性的精确性,确定蝗虫粪便中链烷的回收率。于2007年夏季在内蒙古太仆寺旗天然草地,用优势植物羊草(Leymus chinensis)、糙隐子草(Cleistegenes squarrosa)和克氏针茅(Stipa kylovii)各500g,饲喂360只成虫的亚洲小车蝗(Oedaleus asiaticus)。试验期内每天记录蝗虫实际牧草采食量、采食成分和排粪量,利用气相色谱分析牧草和粪样的链烷含量,应用链烷技术测定蝗虫的牧草采食比例,并与实际值进行比较。结果表明,3种牧草链烷模式存在种间差异;蝗虫粪便中链烷的回收率随链烷长度的增加而线性增加;蝗虫采食羊草、糙隐子草和克氏针茅比例的测定值与实际值存在显著正相关(P<0.05),相关系数分别为0.925 5、0.956 6和0.978 2。因此链烷技术可以精确测定典型草原蝗虫的食物组成。     

Ultrastructure of the excretory system of Brachylaimus aequans (Trematoda: Brachylaimoidea)

The ultrastructure of the flame cell, excretory capillaries, ducts, collecting ducts, excretory bladder, and excretory pore of Brachylaimus aequans was studied 6-8 days p.i. The excretory ducts, collecting ducts and excretory bladder are provided with numerous lamellae on the luminal side. The cilia of lateral flames in the excretory ducts have a triated rootlet. The excretory pore is covered by a tegument identical with the body tegument. The syncytium of the excretory bladder is connected with the tegument of the excretory pore by means of a septate desmosome. No lipid or excretory corpuscles have been demonstrated in the excretory system.     

秦椒田天敌的调查及利用

研究表明:秦椒田天敌有70佘种,主要14种。以蜘蛛、瓢虫、寄生性天敌、食虫蝽为天敌优势类群。各类群天敌在椒田的发生季节和数量不同,主要受地区差异、栽培方式、椒田化学农药使用量的影响。秦椒田天敌种群数量与害虫发生密度成正相关(γ=0.43～0.79),对秦椒田害虫有很强的控制作用。采用麦椒间套、挖窝诱蛛、插种玉米、花生以及合理使用化学农药,对保护椒田天敌效果显著。     

大豆蚜防治适期与防治指标研究

在辽宁,6月下旬大豆蚜种群增长最快,是大豆蚜防治的关键时期。日前,生产上推行百株蚜量一万头的防治指标,可放宽。辽河中下游平原铁丰18大豆,可放宽到2.38—4.07万头;辽豆3号放宽到2.65—3.30万头。以查蚜量为指标,生产上应用困难较大。经研究,卷叶株率与百株蚜量密切相关,(?)=4.283 1.8419x(r=0.90)所以提出以卷叶株率为大面积生产防治的指示指标,铁丰18为10%,辽豆3号为8%。