Speciating Campylobacter jejuni and Campylobacter coli isolates from poultry and humans using six PCR-based assays

Six previously published polymerase chain reaction (PCR) assays each targeting different genes were used to speciate 116 isolates previously identified as Campylobacter jejuni using routine microbiological techniques. Of the 116 isolates, 84 were of poultry origin and 32 of human origin. The six PCR assays confirmed the species identities of 31 of 32 (97%) human isolates and 56 of 84 (67%) poultry isolates as C. jejuni. Twenty eight of 84 (33%) poultry isolates were identified as Campylobacter coli and the remaining human isolate was tentatively identified as Campylobacter upsaliensis based on the degree of similarity of 16S rRNA gene sequences. Four of six published PCR assays showed 100% concordance in their ability to speciate 113 of the 116 (97.4%) isolates; two assays failed to generate a PCR product with four to 10 isolates. A C. coli-specific PCR identified all 28 hippuricase gene (hipO)-negative poultry isolates as C. coli although three isolates confirmed to be C. jejuni by the remaining five assays were also positive in this assay. A PCR-restriction fragment length polymorphism assay based on the 16S rRNA gene was developed, which contrary to the results of the six PCR-based assays, identified 28 of 29 hipO-negative isolates as C. jejuni. DNA sequence analysis of 16S rRNA genes from four hipO-negative poultry isolates showed they were almost identical to the C. jejuni type strain 16S rRNA sequences ATCC43431 and ATCC33560 indicating that assays reliant on 16S rRNA sequence may not be suitable for the differentiation of these two species.

[The effectiveness of rare earth elements as a possible alternative growth promoter for pigs and poultry].

Mixtures of Rare Earth Elements (REE) have been used as animal growth-promoters on a large scale in China during the last 20 years. Numerous studies carried out in China claim it produces quite sensational growth-promoting effects in all categories of farm animals. To explore the question of whether REE's might prove suitable as a growth-promoter under western keeping conditions, feeding experiments were performed on pigs and poultry. The animals received a typical diet, supplemented with REE salts in concentrations between 75 and 300 mg/kg feed. Weight-gain, feed-intake, feed-conversion and (where applicable) laying parameters were observed. It was shown that in pigs receiving feed supplemented with REEs, an increase in daily weight gain of up to 19% and an improvement in feed-conversion of up to 11% can be achieved, whereas, for poultry, no positive effects on growth or productivity of the animals could be observed. Testing of important organs via Neutron Activating Analysis (NAA) showed a minute accumulation of REE, principally in liver and bones. Analysis of the poultry gut-flora, using selective media, showed that the main microorganism populations of the alimentary canal were unaffected by feed-supplementation with REE.

A practical approach to designing syndromic surveillance systems for livestock and poultry

The field of animal syndromic surveillance (SyS) is growing, with many systems being developed worldwide. Now is an appropriate time to share ideas and lessons learned from early SyS design and implementation. Based on our practical experience in animal health SyS, with additions from the public health and animal health SyS literature, we put forward for discussion a 6-step approach to designing SyS systems for livestock and poultry. The first step is to formalise policy and surveillance goals which are considerate of stakeholder expectations and reflect priority issues (1). Next, it is important to find consensus on national priority diseases and identify current surveillance gaps. The geographic, demographic, and temporal coverage of the system must be carefully assessed (2). A minimum dataset for SyS that includes the essential data to achieve all surveillance objectives while minimizing the amount of data collected should be defined. One can then compile an inventory of the data sources available and evaluate each using the criteria developed (3). A list of syndromes should then be produced for all data sources. Cases can be classified into syndrome classes and the data can be converted into time series (4). Based on the characteristics of the syndrome-time series, the length of historic data available and the type of outbreaks the system must detect, different aberration detection algorithms can be tested (5). Finally, it is essential to develop a minimally acceptable response protocol for each statistical signal produced (6). Important outcomes of this pre-operational phase should be building of a national network of experts and collective action and evaluation plans. While some of the more applied steps (4 and 5) are currently receiving consideration, more emphasis should be put on earlier conceptual steps by decision makers and surveillance developers (1-3).

Development of a new real-time polymerase chain reaction assay to detect Duck adenovirus A DNA and application to samples from Swiss poultry flocks.

Between 2008 and 2012, commercial Swiss layer and layer breeder flocks experiencing problems in laying performance were sampled and tested for infection with Duck adenovirus A (DAdV-A; previously known as Egg drop syndrome 1976 virus). Organ samples from birds sent for necropsy as well as blood samples from living animals originating from the same flocks were analyzed. To detect virus-specific DNA, a newly developed quantitative real-time polymerase chain reaction method was applied, and the presence of antibodies against DAdV-A was tested using a commercially available enzyme-linked immunosorbent assay. In 5 out of 7 investigated flocks, viral DNA was detected in tissues. In addition, antibodies against DAdV-A were detected in all of the flocks.

Methods for assessment of keel bone damage in poultry

Keel bone damage (KBD) is a critical issue facing the laying hen industry today as a result of the likely pain leading to compromised welfare and the potential for reduced productivity. Recent reports suggest that damage, while highly variable and likely dependent on a host of factors, extends to all systems (including battery cages, furnished cages, and non-cage systems), genetic lines, and management styles. Despite the extent of the problem, the research community remains uncertain as to the causes and influencing factors of KBD. Although progress has been made investigating these factors, the overall effort is hindered by several issues related to the assessment of KBD, including quality and variation in the methods used between research groups. These issues prevent effective comparison of studies, as well as difficulties in identifying the presence of damage leading to poor accuracy and reliability. The current manuscript seeks to resolve these issues by offering precise definitions for types of KBD, reviewing methods for assessment, and providing recommendations that can improve the accuracy and reliability of those assessments.