Poultry are considered the major reservoir for Campylobacter jejuni, a leading bacterial cause of human food-borne diarrhea. To understand the ecology of C. jejuni and develop strategies to control C. jejuni infection in the animal reservoir, we initiated studies to examine the potential role of anti-Campylobacter maternal antibodies in protecting young broiler chickens from infection by C. jejuni. Using an enzyme-linked immunosorbent assay (ELISA), the prevalence of anti-C. jejuni antibodies in breeder chickens, egg yolks, and broilers from multiple flocks of different farms were examined. High levels of antibodies to the organism were detected in serum samples of breeder chickens and in egg yolk contents. To determine the dynamics of anti-Campylobacter maternal antibody transferred from yolks to hatchlings, serum samples collected from five broiler flocks at weekly intervals from 1 to 28 or 42 days of age were also examined by ELISA. Sera from the 1-day and 7-day-old chicks showed high titers of antibodies to C. jejuni. Thereafter, antibody titers decreased substantially and were not detected during the third and fourth weeks of age. The disappearance of anti-Campylobacter maternal antibodies during 3 to 4 weeks of age coincides with the appearance of C. jejuni infections observed in many broiler chicken flocks. As shown by immunoblotting, the maternally derived antibodies recognized multiple membrane proteins of C. jejuni ranging from 19 to 107 kDa. Moreover, in vitro serum bactericidal assays showed that anti-Campylobacter maternal antibodies were active in antibody-dependent complementmediated killing of C. jejuni. Together, these results highlight the widespread presence of functional antiCampylobacter antibodies in the poultry production system and provide a strong rationale for further investigation of the potential role of anti-C. jejuni maternal antibodies in protecting young chickens from infection by C. jejuni.

Avian paramyxovirus-7 was isolated from a natural outbreak of respiratory tract disease in male and female commercial turkey breeder flocks. The disease spread readily between different housing complexes. The virus was isolated from affected flocks and used for experimental studies in specific-pathogen-free poults. Inoculated and contact-exposed poults developed a respiratory disease characterized by rhinitis and airsacculitis. The virus was isolated from the inoculated and contact-exposed poults, and hemagglutination inhibition antibodies were detected in exposed birds.

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The diversity of animal acoustic signals has evolved due to multiple ecological processes, both biotic and abiotic. At the level of communities of signaling animals, these processes may lead to diverse outcomes, including partitioning of acoustic signals along multiple axes (divergent signal parameters, signaling locations, and timing). Acoustic data provides information on the organization, diversity and dynamics of an acoustic community, and thus enables study of ecological change and turnover in a non-intrusive way. In this review, we lay out how community bioacoustics (the study of acoustic community structure and dynamics), has value in ecological monitoring and conservation of diverse landscapes and taxa. First, we review the concepts of signal space, signal partitioning and their effects on the structure of acoustic communities. Next, we highlight how spatiotemporal ecological change is reflected in acoustic community structure, and the potential this presents in monitoring and conservation. As passive acoustic monitoring gains popularity worldwide, we propose that the analytical framework of community bioacoustics has promise in studying the response of entire suites of species (from insects to large whales) to rapid anthropogenic change.