Genetic improvement programs may improve disease resistance in animal production. The best-characterized genetic control of disease resistance and immune response in animals is the one associated with the Major Histocompatibility Complex (MHC). The ovine lymphocyte antigenof DRB1 gene encodes cell surface glycoproteins that initiate immune responses by presenting processed antigenic peptides to...

Hierarchical structure in bird-habitat associations can arise from hierarchical structure in environmental variables and from the scale-dependent responses of birds to habitat. Hierarchical structure in environmental variables is expected to result from interactions between variables that differ in grain size (spatial resolution) and frequency, and should occur commonly. Birds cannot accurately...

...............................................................................................................................II ACKNOW LEDGEM ENTS.................................................................................................. I l l LIST OF TABLES.................................................................................................................. VI LIST OF FIG ...

Forest fragmentation results in a loss of forest interior and an increase in edge habitat. We studied how understorey bird community composition and habitat variables changed along an edge-to-interior gradient in a 1248-ha lowland rainforest patch in peninsular Malaysia. Birds and environmental variables such as vegetation structure and litter depth were detected within a 25-m radius of each of...

background: the purposes of the present study were morphometric characteri-zation of rostellar hooks of taenia multiceps and to investigate the association of hook length variation and the variability within two mitochondrial genes of sheep isolates of the parasite. methods: up to 4500 sheep brains were examined for the presence of c. cerebralis . biometric characters based on the larval rostel...

Many studies have reported temporal changes in the relative importance of density-dependence and environmental stochasticity in affecting population growth rates, but they typically assume that the predominant factor limiting growth remains constant over long periods of time. Stochastic switches in limiting factors that persist for multiple time-steps have received little attention, but most wi...

The global population of wild tigers remains dangerously low at fewer than 3500 individuals. Habitat loss, along with poaching, can undermine the international target recovery of doubling the number of wild tigers by 2022. Using a new satellite-based monitoring system, we analyzed 14 years of forest loss data within the 76 landscapes (ranging from 278 to 269,983 km(2)) that have been prioritize...

Bighorn sheep currently occupy just 30% of their historic distribution, and persist in populations less than 5% as abundant overall as their early 19th century counterparts. Present-day recovery of bighorn sheep populations is in large part limited by periodic outbreaks of respiratory disease, which can be transmitted to bighorn sheep via contact with domestic sheep grazing in their vicinity. I...

Marine and Environmental Sciences Centre and Institute of Marine Research, University of the Azores, Horta, Portugal, Department of Oceanography and Fisheries, University of the Azores, Horta, Portugal, Centre for Environment, Fisheries and Aquaculture Science, Lowestoft, Suffolk, UK, Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI, USA, Oceanwide Science Institute, Honolu...