An Outbreak of Classical Swine Fever (CSF) in a Closed-Cycle Unit in Israel
In a closed pig holding facility containing 425 sows, located in northern Israel, a Classical Swine Fever (CSF) outbreak occurred, which caused the loss of 267 sows (62.8% of the farm sow population), 4 boars (out of 6), and 828 growing/fattening pigs (41.4% of the total on the farm), through direct mortality, partial culling, and an unknown number of abortions. The CSF outbreak started among the pregnant sows, with high fever, cyanosis, abortions, lameness, vomiting, and mortality (24.8% of sows and 33.3% boars). At necropsy, hemorrhages were found on the parietal pleura, diaphragm, epicardium and kidney; lymph nodes were congested and hemorrhagic; necrotic lesions were present on the mucosa of the small intestine. CSF was diagnosed at Kimron Veterinary Institute by reverse transcriptase polymerase chain reaction (RT-PCR) method and with ELISA-antibody test on serum and ELISA-antigen test on organ homogenates. The results were confirmed by the EU Reference Laboratory at Hanover, Germany with Real Time–PCR on blood and organs. Phylogenetic analysis showed that CSFV sequences of the Israeli virus isolates belonged to genotype 2.1. Molecular typing and comparison of amino acids with CSFV subgroup 2.1 isolates from Southeast Asia and from Europe revealed that the CSFV isolate responsible for the Israeli outbreak was genetically most similar to a Chinese CSFV isolate. Involvement of wild boars, which were in contact with sows was suspected. Samples from blood and organs taken from wild boars found in the vicinity of the farm were found positive for CSF. Following confirmation of CSF, elimination of clinically sick animals and vaccination of the remaining population in the holding and the surrounding area were implemented.
First Outbreak of Porcine Reproductive and Respiratory Virus ( PRRSV ) in Swine Farms in Israel
ABST RACT This article summarizes the clinical findings and confirmation laboratory procedures occurring during the first outbreak the American strain of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), in swine farms in Israel. So far, (2017), Israel has been considered free from PRRS. At least 7 pig farms were involved in the PRRSV outbreak, in the North Region of Israel, involving about 10,000 breeders. Main clinical signs were premature farrowings, increase of stillbirth and pre-weaning mortality. Abortion waves, typical of PRRSV outbreaks, were not observed. PRRSV involvement in the outbreak was confirmed through ELISA-antibody test on blood samples from sows and piglets and RT-PCR on blood and organs. Sequencing and genetic analysis confirmed the involvement of the American PRRSV strain. The outbreak was contained through vaccination of breeders before insemination and at mid-pregnancy, and of piglets before weaning. The source of introduction of PRRSV into Israel remained unknown.
Gut immunity in Lepidopteran insects.
Lepidopteran insects constitute one of the largest fractions of animals on earth, but are considered pests in their relationship with man. Key to the success of this order of insects is its ability to digest food and absorb nutrition, which takes place in the midgut. Because environmental microorganisms can easily enter Lepidopteran guts during feeding, the innate immune response guards against pathogenic bacteria, virus and microsporidia that can be devoured with food. Gut immune responses are complicated by both resident gut microbiota and the surrounding peritrophic membrane and are distinct from immune responses in the body cavity, which depend on the function of the fat body and hemocytes. Due to their relevance to agricultural production, studies of Lepidopteran insect midgut and immunity are receiving more attention, and here we summarize gut structures and functions, and discuss how these confer immunity against different microorganisms. It is expected that increased knowledge of Lepidopteran gut immunity may be utilized for pest biological control in the future.