A survey of 2,003 cecal content samples from chickens, turkeys, cattle, and swine at slaughter facilities in the United States was conducted to estimate the prevalence of the mcr-1 gene conferring resistance to colistin in Enterobacteriaceae. Two cecal samples from swine had Escherichia coli with IncI2 plasmids bearing the mcr-1 gene.

A potential mechanism by which highly pathogenic avian Influenza A virus subtype H5N1 could more readily infect human beings is through the infection of and adaptation in pigs. To detect the occurrence of such infection, monitoring of pig populations through serological screening would be highly desirable. In the current study, hemagglutination inhibition assays were able to detect antibodies against H5N1 developed in pigs, but because of antigenic variation between clades, the use of multiple virus strains were required. Whole recombinant virus and recombinant hemagglutinin antigen enzyme-linked immunosorbent assays (ELISAs) were generated that could detect antibody against multiple H5N1 strains, but which also detected antibody against endemic swine influenza viruses. A recombinant hemagglutinin antigen-based ELISA was as effective as the whole virus antigen ELISAs in detecting antibody against the H5N1 virus strains used and eliminated nearly all of the cross-reactivity with non-H5N1 virus antibody. The current study also highlighted the difficulty in establishing a decision (cutoff) value that would effectively counterbalance nonspecific reactivity against sensitivity. The results provide important information and considerations for the development of serological screening assays for highly pathogenic avian H5N1 viruses.

Porcine circovirus associated disease (PCVAD) encompasses a group of syndromes linked to infection with porcine circovirus type 2 (PCV2). Based on the hypothesis that the immune responses to vaccination versus infection are quantitatively and qualitatively different, the objective of this study was to evaluate immunity, virus replication and disease protection in pigs vaccinated with PCV2 capsid protein (CP) and during infection. The disease model included dual infection with PCV2 and porcine reproductive and respiratory syndrome virus (PRRSV), a virus known to enhance disease progression and severity. The principal effect of PRRSV infection was to increase peak PCV2 viremia by almost 40-fold; however, PCV2 failed to show a reciprocal effect on PRRSV. In vaccinated pigs, there was no evidence of disease or PCV2 replication following dual virus challenge. Immunity following vaccination favored PCV2 neutralizing activity; whereas, PCV2 infection and disease produced high levels of non-neutralizing antibody, primarily directed against a polypeptide in the C-terminal region of CP. These results support the notion that the magnitude of the total antibody response cannot be used as a measure of protective immunity. Furthermore, protection versus disease lies in the immunodominance of specific epitopes. Epitope specificity should be taken into consideration when designing PCV2 vaccines.

Immunomodulators, immunostimulants, and immunotherapies are important tools used by veterinary practitioners and researchers to control and direct the immune system of small animals. This article is an overview and summary of some of the most common immunomodulatory agents used in companion animals emphasizing steroidal and nonsteroidal agents, T-cell inhibitors, cytotoxic drugs, immunostimulators and biologic response modifying agents, and neoplasia chemotherapeutic agents.

Background: Babesia are emerging health threats to humans and animals in the United States. A collaborative effort of multiple disciplines to attain optimal health for people, animals and our environment, otherwise known as the One Health concept, was taken during a research workshop held in April 2009 to identify gaps in scientific knowledge regarding babesioses. The impetus for this analysis was the increased risk for outbreaks of bovine babesiosis, also known as Texas cattle fever, associated with the re-infestation of the U. S. by cattle fever ticks.Results: The involvement of wildlife in the ecology of cattle fever ticks jeopardizes the ability of state and federal agencies to keep the national herd free of Texas cattle fever. Similarly, there has been a progressive increase in the number of cases of human babesiosis over the past 25 years due to an increase in the white-tailed deer population. Human babesiosis due to cattle-associated Babesia divergens and Babesia divergens-like organisms have begun to appear in residents of the United States. Research needs for human and bovine babesioses were identified and are presented herein.Conclusions: The translation of this research is expected to provide veterinary and public health systems with the tools to mitigate the impact of bovine and human babesioses. However, economic, political, and social commitments are urgently required, including increased national funding for animal and human Babesia research, to prevent the re-establishment of cattle fever ticks and the increasing problem of human babesiosis in the United States.

Three vaccination challenge studies were performed to evaluate the impact on vaccine efficacy of combining porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae vaccines. Piglets were vaccinated with either a M hyopneumoniae bacterin, a modified live PRRSV vaccine based on a European-type PRRSV strain, or a combination of both vaccines, followed by experimental infection with either M hyopneumoniae or PRRSV. Vaccine efficacy was evaluated by assessing lung lesion scores for M hyopneumoniae and measuring viraemia for PRRSV. There were no significant differences between the protective efficacy of the combined vaccine protocol and the protective efficacy of the two single vaccines, indicating that PRRSV vaccination did not interfere with M hyopneumoniae vaccine efficacy and vice versa.

Oral Presentation A1 Bilateral Intratubal Artificial Insemination with Frozen-thaw Semen in rhFSH-Induced Oestrous Cats Ajjima Chansaenroj, Paweena Thuwanut, Kaywalee Chatdarong, Suppawiwat Ponglowhapan 109 A2 The Relationship Between Serum IGF–I and Puberty Attainment in Gilts Atthaporn Roongsitthichai, Junpen Suwimonteerabutr, Seri Koonjaenak, Padet Tummaruk 111 A3 Comparison of Frozen-thawed Epididymal Dog Sperm Quality after Cold Stored in Epididymis and in Extender Nadthagarn Gleawketgarn,Chiti Hoonaukit,Nopmanee Taechangam, Kaywalee Chatdarong 113 A4 Cat Ovarian Tissue Cryopreservation Using a Passive Cooling Device Nae Tanpradit, Kaywalee Chatdarong 115 A5 Extracellular Adenosine 5’-triphosphate (ATPe): Effects on Cryopreserved Epididymal Cat Sperm Paweena Thuwanut, Kaywalee Chatdarong 117 A6 Reproductive Performances of Cross Breed Dairy Cows of Small Holder Farmers in Northern of Thailand Suvichai Rojanasthien,Terdsak Yano A7 Efficiency of CIDR-B Application on Follicular Response, Ovulation Time and Synchronization Rate in Thai Swamp Buffaloes Thuchadaporn Chaikhun, Fabio De Rensis, Mongkol Techakumphu, Siriwat Suadsong 119

The objective of this study was to assess the effect of concurrent infection with porcine reproductive and respiratory syndrome virus (PRRSV) on the efficacy of an inactivated swine influenza virus (SIV) vaccine. Eight groups of pigs were infected with a virulent PRRSV isolate either between the two SIV vaccines or at the time of SIV challenge. Control groups included SIV vaccination without PRRSV and pigs infected with SIV and/or PRRSV. Pigs infected with PRRSV during vaccination showed increased levels of macroscopic and microscopic lesions compared to pigs vaccinated against and challenged with only SIV indicating decreased SIV vaccine efficacy. In addition, pigs vaccinated in the presence of PRRSV showed increased clinical disease and shedding of SIV during the acute phase of SIV infection. No alterations in the systemic or local antibody response to either SIV vaccination or challenge were observed. These findings demonstrate that PRRSV infection has a significant impact on SIV vaccine efficacy that may be important for disease control.

The response to infection from porcine reproductive and respiratory syndrome virus (PRRSV) for 2 genetically diverse commercial pig lines was investigated. Seventy-two pigs from each line, aged 6 wk, were challenged with PRRSV VR-2385, and 66 littermates served as control. The clinical response to infection was monitored throughout the study and pigs were necropsied at 10 or 21 d postinfection. Previous analyses showed significant line differences in susceptibility to PRRSV infection. This study also revealed significant line differences in growth during infection. Line B, characterized by faster growth rate than line A in the absence of infection, suffered more severe clinical disease and greater reduction in BW growth after infection. Correlations between growth and disease-related traits were generally negative, albeit weak. Correlations were also weak among most clinical and pathological traits. Clinical disease traits such as respiratory scores and rectal temperatures were poor indicators of virus levels, pathological damage, or growth during PRRSV infection. Relationships between traits varied over time, indicating that different disease-related mechanisms may operate at different time scales and, therefore, that the time of assessing host responses may influence the conclusions drawn about biological significance. Three possible mechanisms underlying growth under PRRSV infection were proposed based on evidence from this and previous studies. It was concluded that a comprehensive framework describing the interaction between the biological mechanisms and the genetic influence on these would be desirable for achieving progress in the genetic control of this economically important disease.

A swine influenza virus (SIV) vaccine-challenge pig model was used to study the potential of a conserved matrix 2 (M2) protein vaccine alone or in combination with an inactivated H1N1-vaccine to protect against H1N1 and H1N2 viruses. The H1N1-vaccine and heterologous H1N2-challenge virus model has previously been shown to prolong fever and increase SIV-associated pneumonic lesions. The M2 vaccine in combination with the H1N1-vaccine reduced the H1N2 induced fever but not virus shedding. The M2 vaccine alone reduced respiratory signs and pneumonic lesions to levels similar to the negative control pigs following H1N2 infection. This study found that the M2 protein has potential as a vaccine for SIV-associated disease prevention. However, development of an immune response towards the major envelope HA protein was required to reduce SIV shedding.

Materials and methods: Two challenge studies were performed in which pigs received two doses of either saline (nonvaccinated groups) or an M hyo bacterin (vaccinated groups), followed 3 weeks later by intratracheal inoculation of each pig with one of two M hyo field isolates. Necropsies were performed 28 or 30 days post challenge. Vaccine efficacy was determined by evaluating macroscopic lung lesions, DNA levels of M hyo in bronchial alveolar lavage fluids (BALF), Peer ­reviewed

Influenza viruses are able to infect humans, swine, and avian species, and swine have long been considered a potential source of new influenza viruses that can infect humans. Swine have receptors to which both avian and mammalian influenza viruses bind, which increases the potential for viruses to exchange genetic sequences and produce new reassortant viruses in swine. A number of genetically diverse viruses are circulating in swine herds throughout the world and are a major cause of concern to the swine industry. Control of swine influenza is primarily through the vaccination of sows, to protect young pigs through maternally derived antibodies. However, influenza viruses continue to circulate in pigs after the decay of maternal antibodies, providing a continuing source of virus on a herd basis. Measures to control avian influenza in commercial poultry operations are dictated by the virulence of the virus. Detection of a highly pathogenic avian influenza (HPAI) virus results in immediate elimination of the flock. Low-pathogenic avian influenza viruses are controlled through vaccination, which is done primarily in turkey flocks. Maintenance of the current HPAI virus-free status of poultry in the United States is through constant surveillance of poultry flocks. Although current influenza vaccines for poultry and swine are inactivated and adjuvanted, ongoing research into the development of newer vaccines, such as DNA, live-virus, or vectored vaccines, is being done. Control of influenza virus infection in poultry and swine is critical to the reduction of potential cross-species adaptation and spread of influenza viruses, which will minimize the risk of animals being the source of the next pandemic.

ABSTRACT Mycoplasma hyopneumoniae is an important cause of pneumonia in pigs around the world, but confirming its presence in (or absence from) pigs can be difficult. Culture for diagnosis is impractical, and seroconversion is often delayed after natural infection, limiting the use of serology. Numerous PCR assays for the detection of M . hyopneumoniae have been developed, targeting several different genes. Recently, genetic diversity among strains of M . hyopneumoniae was demonstrated. The effect of this diversity on the accuracy and sensitivity of the M . hyopneumoniae PCR assays could result in false-negative results in current PCR tests. In this study, a panel of isolates of M . hyopneumoniae , M. flocculare , M. hyorhinis , and M. hyosynoviae were tested with a number of M . hyopneumoniae -specific PCR assays. Some M . hyopneumoniae PCR assays tested did not detect all isolates of M . hyopneumoniae . To increase the efficiency of PCR testing, two new real-time PCR assays that are specific and capable of detecting all of the M . hyopneumoniae isolates used in this study were developed.

Atemwegserkrankungen stellen beim Schwein die sowohl aus klinischer als auch aus ökonomischer Sicht relevantesten infektiös bedingten gesundheitlichen Probleme dar, wobei die respiratorischen Erkrankungskomplexe durch das zeitgleiche oder zeitversetzte Auftreten verschiedener Erreger bedingt sind. Außerdem können sich einzelne Erreger gegenseitig beeinflussen und das Krankheitsbild verstärken. Zusätzlich begünstigen nichtinfektiöse Faktoren die Atemwegserkrankungen, wie beispielsweise das Stallklima. Ein typisches Beispiel für den Zusammenhang von nichtinfektiösen Faktoren und infektiösen Erregern ist der Porcine Respiratory Disease Complex (PRDC).

The influenza invariant matrix 2 (M2) protein is a potential subunit vaccine candidate to induce protective immunity against broader strains of influenza A viruses (IAV). Antibodies to M2 protein have not been well characterized in IAV natural hosts. To characterize M2-specific antibodies in pigs, an ELISA to the extracellular region of the M2 (M2e) protein was developed. Sera from pigs experimentally infected with three different swine influenza virus (SIV) subtypes, immunized with an SIV inactivated vaccine, or positive for SIV maternally derived antibodies (MDA) in the absence of SIV infection were tested in assay. Confirmation of antibody titer status of pigs, was determined using a hemagglutination-inhibition (HI) test and the presence of antibodies to matrix 1 (M1) protein was measured by a recombinant M1 (rM1)-based ELISA. The antibody titers to the HA and M2e proteins but not to the rM1 were directly correlated to the dose of virus used to infect the pigs and the level of antibodies detected by the HI assay varied according to SIV subtype. Pigs experimentally infected with SIV produced low levels of M2e antibodies compared to antibodies detected by the HI and rM1 assays. Vaccination alone followed by infection did not increase the levels of M2e antibodies in contrast to HA and rM1 antibodies. Pigs with MDA had different levels of HA antibodies and were positive to M2e antibodies, but results were not correlated to HA antibodies levels and inconsistently present.

The goal of this study was to examine the effect of porcine circovirus type 2 (PCV2) infection and replication on peripheral blood mononuclear cells (PBMCs) in the presence of mitogens, concanavalin A (ConA) or pokeweed mitogen (PWM) in vitro. The level of PCV2 replication and the impact of infection on PBMC proliferation, viability and the level of apoptosis in the presence or absence of mitogen stimulation were assessed. Mitogen stimulation increased viral replication in PBMCs as measured by the amount of spliced capsid mRNA (Cap mRNA). However, cell proliferation alone had no significant impact on PCV2 replication as the level of Cap mRNA in ConA or PWM stimulated PBMCs was not increased in proliferating cells compared to non-proliferating cells. No significant differences were observed in the level of PCV2 replication product in PBMCs stimulated with ConA for 12, 36, and 72 h prior to infection. Infection with PCV2 did not affect the ability of PBMCs to proliferate in response to ConA or PWM stimulation in vitro. Increased apoptosis was associated with PCV2 infection in PWM stimulated PBMCs. Interestingly, a significantly lower apoptotic index was observed in PCV2 infected PBMCs compared to mock-infected cells in the absence of mitogens. This study determined that the rate of PCV2 replication increases with cell stimulation and apoptosis is increased following PCV2 infection under certain stimulation conditions. These results further suggest that PCV2 requires a specific stimulation or trigger for increased viral replication, which is independent of cell proliferation.

Swine influenza virus is an economically important pathogen to the U.S. swine industry. New influenza subtypes and isolates within subtypes with different genetic and antigenic makeup have recently emerged in U.S. swineherds. As a result of the emergence of these new viruses, diagnosticians' ability to accurately diagnose influenza infection in pigs and develop appropriate vaccine strategies has become increasingly difficult. The current study compares the ability of subtype-specific commercial enzyme-linked immunosorbent assays (ELISA), hemagglutination inhibition (HI), and serum neutralization (SN) assays to detect antibodies elicited by multiple isolates within different subtypes of influenza virus. Pigs were infected with genetically and antigenically different isolates of the 3 major circulating subtypes within populations of swine (H1N1, H1N2, and H3N2). Serum was collected when all pigs within a group collectively reached HI reciprocal titers ≥160 against that group's homologous challenge virus. The antibody cross-reactivity of the sera between isolates was determined using ELISA, HI, and SN assays. In addition, the correlation between the 3 assays was determined. The assays differed in their ability to detect antibodies produced by the viruses used in the study. The results provide important information to diagnostic laboratories, veterinarians, and swine producers on the ability of 3 common serological assays used in identifying infection with influenza in pigs.