Genetics of behavior in the silver fox

The silver fox provides a rich resource for investigating the genetics of behavior, with strains developed by intensely selective breeding that display markedly different behavioral phenotypes. Until recently, however, the tools for conducting molecular genetic investigations in this species were very limited. In this review, the history of development of this resource and the tools to exploit it are described. Although the focus is on the genetics of domestication in the silver fox, there is a broader context. In particular, one expectation of the silver fox research is that it will be synergistic with studies in other species, including humans, to yield a more comprehensive understanding of the molecular mechanisms and evolution of a wider range of social cognitive behaviors.     

Formation of biofilms as an example of the social behavior of bacteria

This paper is a brief review of data on bacterial biofilms that occur inside and outside of host organisms. Such biofilms are of great ecological and clinical importance. The role of interspecies communications in the development of bacterial biofilms and infectious diseases is particularly emphasized. Considerable attention is given to the electron microscopic study of biofilms formed by Salmonella typhimurium cells incubated as a broth culture in microtubes without aeration. Bacterial samples taken from the biofilm and planktonic culture grown in the same microtube were comparatively investigated by transmission electron microscopy.     

Formation of biofilms as an example of the social behavior of bacteria

This paper is a brief review of data on bacterial biofilms that occur inside and outside of host organisms. Such biofilms are of great ecological and clinical importance. The role of interspecies communications in the development of bacterial biofilms and infectious diseases is particularly emphasized. Considerable attention is given to the electron microscopic study of biofilms formed by Salmonella typhimurium cells incubated as a broth culture in microtubes without aeration. Bacterial samples taken from the biofilm and planktonic culture grown in the same microtube were comparatively investigated by transmission electron microscopy.     

Effects of selection for behavior, human approach mode and sex on vocalization in silver fox

This study presents a first direct comparison of vocal type, call rate and time spent vocalizing among Unselected, Tame and Aggressive strains of silver fox (Vulpes vulpes) in three modes of human approach (Provoking, Approach–Retreat, and Static). Also, it provides a first comparison of male and female vocal output in the Provoking test. Vocal types were found strain-specific irrespective of the fox sex or the test. Males had higher call rates and spent shorter times vocalizing than females. These results support the evidence of genetic-based emotional states, triggering vocal behavior in silver fox strains, and suggest sex dimorphism in vocal activity toward humans.     

Methodological approach to calculating average growth (increment) rates in epidemiological analysis

In an analysis of dynamic rows with a view to the calculation of the rate of growth (increase) with the use of the geometric mean, it is expedient to utilize not the actual data, but the characteristics of the straight line aligned by the least-square method. The calculation of the average rate of growth (increase) by the actual data is recommended only in case of the monotonous change of the measured characteristic.     

以田鼠作为动物模型来研究社会行为的进化:基因、脑与行为

田鼠属的一些近缘种间具有独特的社会行为多态性。例如Microtusochrogaster和M .pinetorum为一夫一妻制 ,而M .montanus和M .pennsylvanicus则为独居和一夫多妻制。无论是在野外还是人工饲养的条件下 ,单配制的田鼠其雌、雄成年个体一经交配即在两者之间形成长期的配偶关系并且双亲共同哺育后代。已证明神经多肽加压素 (Vasopressin)参与了田鼠单配制行为的神经调控。本篇综述了过去以及近期关于加压素调控田鼠配偶关系形成的研究结果和进展。首先 ,阐述了加压素V1a受体 (V1aR)在脑分布的种间差异 ,并以此来鉴别特定脑区在配偶关系形成中的功能 ;其次 ,探讨了运用V1aR拮抗物的药理学方法来决定究竟哪些脑区参与配偶关系的形成 ,还描述了田鼠种间V1aR基因结构和功能的不同 ,以及这些不同对V1aR在大脑的分布和行为调控潜在的作用机制 ;最后 ,讨论了最新的研究结果 ,即对一夫多妻制田鼠进行脑V1aR基因的改造 ,从而使之表现出一夫一妻制田鼠的行为。总之 ,了解复杂的社会性行为的遗传和神经机制可以加深我们对种间和种内行为分歧进化的理解     

A statistical approach to study the dynamics of micropropagation rates, using banana (Musa spp.) as an example

The use of micropropagation to obtain large numbers of high-quality planting material has increased in recent years. Behavior in culture, mainly in terms of multiplication rate, varies among genotypes, directly affecting plant production planning. To study multiplication rates over time, suckers of banana, Musa spp., cv. Maçã, were collected in the field and the shoot apex introduced in vitro for micropropagation. The number of new shoots produced in each of the six multiplication cycles was recorded and the data analyzed statistically. Variability in total shoot production and differences in multiplication rates was considerable among families, which consisted of the initial explant and its progeny. Moreover, the adjusted Poisson regression models for the number of shoots showed that the multiplication rate in this cultivar tends to decrease with time: after the seventh subculture, new shoots may form at a very low rate. Interpretation of the first and second derivatives of the regression model allowed determination of the maximum speed of multiplication and the time at which the multiplication rate begins to decline.     

Photoperiodic regulation of reproduction in the male silver fox (Vulpes vulpes)

Six silver fox males were exposed to short days (6L:18D) from February, when the testes were fully developed, until June 1986 (Group 6L). Eight males maintained in natural daylight served as controls (Group N). Histological sections from the testes of 2 males in Group 6L killed in June indicated full spermatogenic activity. Three blue fox vixens inseminated the following year with semen collected and frozen in June from 3 males in Group 6L failed to produce litters. One possible explanation for the reproductive failures could have been that the high environmental temperatures in June influenced semen quality. There was no significant difference (P greater than 0.05) in LH release in response to GnRH stimulation in June, but testosterone response to LH release was significantly higher (P less than 0.01) in animals subjected to a restricted photoperiod, demonstrating that testicular testosterone production was maintained longer than in control animals. Two males in Group 6L were retained in 6L:18D from June until December 1986 and then exposed to natural daylight until the end of the study in May 1987 (Group 6L:6L:N). These males started to shed their winter coat and showed clinical signs of testicular regression in December, i.e. after approximately 11 months exposure to 6L:18D. The 2 remaining males in Group 6L were moved to cages with natural daylight in June 1986, where they were kept until the end of the experiment (Group 6L: N:N). These males displayed testicular regression soon after the change in photoperiod but maintained their capacity for testicular redevelopment during the following breeding season.(ABSTRACT TRUNCATED AT 250 WORDS)     

Multivariate geometry as an approach to algal community analysis

Multivariate analyses are put in the context of more usual approaches to phycological investigations. The intuitive common-sense involved in methods of ordination, classification and discrimination are emphasised by simple geometric accounts which avoid jargon and matrix algebra. Warnings are given that artifacts result from technique abuses by the naive or over-enthusiastic. An analysis of a simple periphyton data set is presented as an example of the approach. Suggestions are made as to situations in phycological investigations, where the techniques could be appropriate. The discipline is reprimanded for its neglect of the multivariate approach.     

Using "travel time" data to characterize the behavior of migrating animals

For migratory species, duration of migration, or "travel time," is often a critical variable in determining the cost of migration. Observed travel times are the result of both environmental factors such as air or water currents and the behavior of individuals. In an effort to distinguish among these components, I developed a migration model based on an advection-diffusion equation that characterizes population movements in terms of two biologically meaningful parameters: migration rate and rate of population spread. I applied the model to travel time data from juvenile chinook salmon (Onchorhynchus tshawytscha), which were tagged during their seaward migration. The tagged fish originated from three separate evolutionarily significant units (ESUs) as classified by the U. S. National Marine Fisheries Service. The model was expanded by allowing migration and diffusion rates to vary with fish length and river flow. Variability in travel times explained by these factors was strikingly similar from year to year within ESUs, and the migratory behavior revealed by the analysis was consistent with the life-history patterns that distinguish the ESUs. The approach presented here is easily adaptable to a wide range of migratory species and may be particularly useful for predicting how at-risk populations respond to variable conditions in regulated or otherwise disturbed migration habitats.     

Using functional trait diversity to infer community assembly mechanisms: an exclosure experiment as an example

AimsThe Qinghai-Tibetan Plateau has a mean altitude exceeding 4000 m and covers about 2.5 million km2. More than 60% of this area is alpine grassland. Exclosures have been widely used in this region to study the sustainable use of grassland resources. We used patterns of functional trait diversity to infer the effects of exclosures on community assembly in alpine meadows.     

Using gonadotropin-releasing hormone (GnRH) and GnRH analogs to modulate testis function and enhance the productivity of domestic animals

Gonadotropin releasing hormone (GnRH) controls the activity of the gonadotrope cells of the pituitary gland and, as a consequence, is a critical component of the endocrine cascade that determines the growth, development, and functional activity of testicular tissue. The use of GnRH and GnRH analogs is common in domestic animal production systems. Although GnRH and GnRH analogs are most commonly used to control the fertility and reproductive events in female animals, GnRH agonists and antagonists are increasingly used to modulate the fertility, behavior, and productivity of male animals as well. This review will focus on recent advances in this use of GnRH agonists and antagonists.     

Lectin affinity as an approach to the proteomic analysis of membrane glycoproteins

The aim was to determine the proportion of membrane glycoproteins captured using concanavalin A or wheat germ agglutinin lectin affinity chromatography. Digests of the isolated proteins were separated by reversed-phase liquid chromatography and analyzed by matrix-assisted laser desorption tandem mass spectrometry. The two lectins identified different groups of proteins with a broad range of molecular mass and p/ values, including a number of proteins that overlapped the two groups. Approximately 30% of the proteins were positively identified as containing domains that were predicted using standard bioinformatics methods to be characteristic of integral membrane proteins. This approach represents an effective method of surveying the membrane protein pool of mammalian cells for subsequent proteomic analysis.