The size and species composition of bird flocks in a mixed-conifer forest of the western Sierra Nevada was nearly identical over three winters. Golden-crowned Kinglets (Regulus satrapa), Chestnut-backed Chickadees (Parus rufescens), and Red-breasted Nuthatches (Sitta canadensis) had the highest number of individuals/flock. Kindets and nuthatches were the most frequent flockmembers, although the...

The two classes of semifield spreads of Cossidente et al. arising from their Hermitian ovoids are completely determined as a set of Kantor-Knuth flock semifield spreads and a set of Hughes-Kleinfeld semifield spreads.

We sampled 1,091 Icelandic broiler flocks at slaughter from May 2001 to December 2003 to determine the prevalence of, and investigate risk factors for the presence of, Campylobacter spp. at the flock level. Approximately 15% of the flocks were positive for Campylobacter spp.; most (95%) of the infected flocks being raised during the months of April-September. Based on the data from the latter m...

Vigilance (scanning) and other behavior patterns were studied in free-ranging Evening Grosbeaks (Coccothraustes vespertinus) at feeders to assess how flock size and flock geometry influenced the behavior of individual birds. The present results indicate that the way in which individual grosbeaks are positioned with respect to one another effects many aspects of their behavior, especially when a...

A study was undertaken to test the effect of 2 commercially available probiotics on the production efficiency of broiler chickens hatched from the same breeder flock at 3 different ages (28, 43, and 57 wk). At each of the 3 breeder flock ages, 1,600 broiler chickens were hatched and randomly allocated to 1 of 4 treatments: 1) no probiotics (control), 2) probiotic 1 administered in the drinking ...

BACKGROUND Prevention and control of ovine enzootic abortion (OEA) can be achieved by application of a live vaccine. In this study, five sheep flocks with different vaccination and infection status were serologically tested using a competitive enzyme-linked immunosorbent assay (cELISA) specific for Chlamydophila (Cp.) abortus over a two-year time period. RESULTS Sheep in Flock A with recent O...

We show that an elation generalised quadrangle which has p + 1 lines on each point, for some prime p, is classical or arises from a flock of a quadratic cone (i.e., is a flock quadrangle).

We prove that the elation groups of a certain infinite family of Roman generalized quadrangles are not isomorphic to those of associated flock generalized quadrangles.

Since the 1980s, the prevalence of Salmonella in Belgian poultry layers and broilers has greatly fluctuated with a rise observed in 2003 and a significant decrease in 2005. In order to alleviate the risk at egg consumer level, it is crucial to understand the factors which influence the contamination and the spread of Salmonella in laying hens. To study such determinants we explored the Belgian ...