This study was conducted to observe the occurrence of aflatoxin in chicken feed from Peninsular Malaysia. A total of 336 samples of chicken feed from Peninsular Malaysia were conveniently collected in this survey. The chicken feed represented the following three categories which are starter, grower and finisher. All samples werecollected from local poultry farms in East Coast Region (Kelantan, Terengganu, and Pahang), Northern Region (Perlis, Kedah, Penang, and Perak), Southern Region (Malacca, Johor) and Central Region (Selangor, Negeri Sembilan) of Peninsular Malaysia for a periodof six months (July-December 2015). Enzymelinked immunosorbent assay (ELISA) was used for screening of total aflatoxin (TA) in the samples. High performance liquid chromatography (HPLC) with fluorescence detector was used for determination of aflatoxin B and G. Moisture content of samples was determined using the hot airoven method (AOAC International, 2011). Overall, the incidence of positive TA >20 µg/kg in chicken feed is 14.9% (50 samples). The average level of TA was found significantly different between different states at p<0.05 for both broiler grower and finisher. Thechromatograph results showed that positive samples were found in broiler finisher from Kedah (94.6 µg/kg and 42.1 µg/kg) and Penang(56.4 µg/kg) with aflatoxin B1. In this study, the range of moisture content were around 6.5-27.3%. About 40% samples have more than12% moisture content. One of the predisposing factors for aflatoxin accumulation in chicken feed is moisture content. The results warrantthe need for surveillance and constant monitoring programmes for the prevention of aflatoxin incidence in poultry farms.

This study was conducted to investigate the high mortality of young lambs in two sheep farms in Pekan, Pahang over a period of 3 years. Samples from postmortem of 1,451 lambs below one year of age by a farm veterinarian were submitted for laboratory diagnosis at the Bacteriology Section of the Regional Veterinary Diagnostic Laboratory in Kuantan. Escherichia coli is the most commonly recorded bacteria with 161 lambs diagnosed in 2013. In 2014 and 2015, there was a decrease in occurrence of E. coli related deaths, with 120 and 75lambs respectively. A total of 25% of the cases showed Escherichia coli positive by culture on blood agar and MacConkey agar, and confirmed by biochemical tests. A total of 21% of the cases were positive for staphylococcus sp, 3% and 6% for Streptococcus sp and Klebsiella pneumonia, respectively. Other bacteria were isolated in 45% of the cases. It was further noted that a total of 285 lambs between the ages of one to four months of age followed by 58 lambs (20%) less than one month old had E.coli isolation. It is also noteworthy that there were 10 lambs with E.coli infection in one to fourteen day-old lambs during the 3-year period from January 2013 to December 2015. This information was collated as a result of routine diagnosis of field cases submitted and with the intention of highlighting the common pathogens causing high mortality in local small ruminant farms so that preventive action may be taken for future farming ventures. E. coli infections or Colibacillosis is an important finding and indicator of poor management including poor nutrition, hygiene and environmental contamination which can reduce animal immunity and render it susceptible to other infections.

Porcine diarrhea outbreaks caused by porcine epidemic diarrhea virus (PEDV) has occurred in China with significant losses of piglets since 2010. In this study, the complete S and ORF3 genes of 15 field PEDV isolates in mid-eastern China from 2011 to 2013 were detected and compared with other reference strains. Based on S gene, all of the PEDV strains could be assigned to 3 genogroups. Only 1 isolate, JS120103, belonged to genogroup 1 and showed a close relationship with previous Chinese strains DX and JS-2004-2, European strain CV777, and Korean strain DR13. The other 14 isolates belonged to genogroup 3 and showed a close relationship with other Chinese strains isolated after 2010. The S genes of those isolates were 9 nucleotides longer in length than JS120103 and the other reference strains in genogroup 1, with 15 bp insertion and 6 bp deletion. Homology analyses revealed that all of the Chinese field isolates, except JS120103, are 97.6% to 100% (95.8% to 100%) identical in nucleotide (deduced amino acid) sequence to each other. Meanwhile, based on the ORF3 gene, all of the PEDV isolates could be separated into 3 genogroups. Eleven of the 15 field isolates in this study belonged to genogroup 3 and were 95.8% to 100% identical in nucleotide sequence or 95.6% to 100% in deduced amino acid sequence to each other. Our results indicate that the variant PEDV strain spread wildly in mid-eastern China. This will be useful to take into consideration in the control and prevention of this disease.

Administration of an N-lauroylsarcosine-derived outer membrane protein fraction of Pasteurella haemolytica A1 (SCI-1) induced a protective response in calves against intrathoracic challenge exposure with the homologous serovar. Outer membrane proteins from heterologous serovars, A6 and A9, induced partial protection that was associated with their respective similarities to serovar A1 in outer membrane protein profiles derived by use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Calves vaccinated with SCI preparations did not have detectable neutralizing antibody to P haemolytica A1 leukotoxin. Antibodies to whole-cell antigens, carbohydrate-protein subunit antigen, and SCI-1 were associated with resistance, which indicates that protein antigens shared among cell surface, carbohydrate-protein subunit, and SCI preparations are immunogenic and enhance resistance to experimental challenge exposure.

Vaccination of cattle with a tissue culture-derived Pasteurella haemolytica serotype 1 vaccine elicited a serotype-specific inhibition of nasal and tonsillar colonization by the homologous serotype under field conditions. Calves (n = 101) originated from a single farm, where half the calves were vaccinated. The calves were delivered to an order-buyer barn 105 days later, and given a second dose of vaccine. At the order-buyer barn, calves were mixed with 27 calves, some of which had clinical signs consistent with respiratory tract disease. Also 12 of the original calves were infected with P haemolytica serotype 1 by tonsillar instillation. After 6 days at the order-buyer barn, calves were shipped 1,600 km by truck to a feedyard, and arrived the next day. Tonsillar wash and nasal secretion aspiration specimens were collected for culture of P haemolytica on days 1, 8, and 29 at the feedyard. Inhibition of colonization was evidenced by lower frequency of isolations from the vaccinates than from the nonvaccinates after transport to the feedyard. Selectively lowering the frequency of colonization by P haemolytica serotype 1 could reduce losses attributable to pneumonic pasteurellosis.

Poly(methacrylic acid) hydrogels were tested for oral delivery of a vaccine against Pasteurella haemolytica infection in cattle. Culture supernatants of P haemolytica, the most common bacterium associated with pneumonia in cattle, were used as the antigens in the vaccine. Hydrogels containing culture supernatants were administered orally to calves. Calves were then challenge-exposed with virulent P haemolytica. Calves were euthanatized 3 days after challenge exposure. The lungs of each calf were scored for severity and size of pneumonic lesions. Results indicated that vaccinated calves had smaller, less severe pneumonic lesions and lived longer than nonvaccinated calves. These results indicated that hydrogels can be used to deliver vaccines orally to calves to enhance resistance to pneumonia caused by P haemolytica.

Aerosol vaccination is used effectively to immunize poultry against Newcastle disease, but to the authors' knowledge, this vaccination procedure is not well studied in other species. The efficacy of IM and aerosol vaccination of pigs against Mycoplasma hyopneumoniae infection was evaluated. Twenty-one pigs from a Mycoplasma-free herd were randomly allotted by litter and body weight into 3 groups. One group was given aerosolized phosphate-buffered saline solution (PBSS) by inhalation. The second group (AERO) was given aerosolized M hyopneumoniae vaccine by inhalation. The third group (IM) was given the same vaccine by IM injection. Vaccination by IM administration was repeated once, and aerosol vaccination was repeated twice at 2-week intervals. Two weeks after the last vaccination, all pigs were intratracheally challenge-exposed with 3 ml of broth culture containing 10(7) color-changing units (CCU) of a low-passage strain of virulent M hyopneumoniae. Pigs were observed daily for coughing. Four weeks after challenge exposure, all pigs were necropsied. Percentage of lung affected by gross pneumonia was measured, bronchioalveolar lavage fluid (BALF) cells were counted, and quantitative culture for mycoplasmas was performed on lung sections. Additionally, M hyopneumoniae-specific antibodies were measured in prevaccination, postvaccination, and postchallenge-exposure serum and BALF by use of indirect ELISA. Mean prevalence of persistent coughing in pigs of the AERO group (4.6 d/pig) was not different from that in pigs of the PBSS group (3.7 d/pig). Prevalence of coughing in IM vaccinated pigs (1.0 d/ pig) was lower (P < 0.05) than that in pigs of the PBSS group. Mean gross lung lesion scores and BALF cell counts were not different between the AERO (15% pneumonia, 5,233 cells/microliter) and PBSS (11% pneumonia, 3,022 cells/microliter) groups, but were lower (P < 0.05) in the IM group (1.5% pneumonia, 400 cells/microliter) than in the PBSS group. Mean lung mycoplasmal counts were not significantly (P < 0.05) different among the PBSS (10(5.6) CCU/g), AERO (10(5.3) CCU/g), and IM (10(3.3) CCU/g) groups. Postvaccination M hyopneumoniae-specific IgG or IgA was not detectable in BALF after either vaccination procedure. Postvaccination M hyopneumoniae-specific serum IgG concentration was not different among the 3 groups. Postchallenge exposure M hyopneumoniae-specific IgG and IgA were detectable in BALF of all pigs, but were not different among the 3 treatment groups. Postchallenge exposure-specific serum IgG concentration was not different between the PBSS (mean OD, 0.739) and AERO (mean OD, 0.672) groups, but was higher (P < 0.05) in the IM group (mean OD, 1.185) than in the PBSS group. Aerosol vaccination failed to induce local and systemic antibody responses detectable by ELISA, and failed to protect pigs against mycoplasmal pneumonia. Intramuscular vaccination failed to induce local and systemic antibody responses detectable by ELISA, but substantially reduced the clinical signs and lesions caused by challenge exposure to virulent M hyopneumoniae.

A study was conducted to determine the effect of mono-phosphoryl lipid A (MPL) and trehalose dimycolate (TDM) as adjuvants on the protective responses in BALB/c mice vaccinated with Brucella abortus salt-extractable protein (BCSP) or proteinase-K-treated B abortus lipopolysaccharide (PKLPS). Mice were vaccinated with different doses of BCSP or PKLPS given alone or in combination with MPL or TDM. Mice were challenge-exposed 4 weeks later with virulent B abortus strain 2308. Two weeks after challenge exposure, the number of B abortus colony-forming units (CFU) per spleen, spleen weights, and spleen cell interleukin 1 production were measured. Serum IgG and IgM concentrations specific for vaccinal immunogens were measured before and after challenge exposure with B abortus. Spleen weights and mean B abortus CFU per vaccine group were significantly lower in BCSP- and PKLPS-vaccinated mice, compared with those of nonvaccinated control mice. Monophosphoryl lipid A enhanced the suppression of splenic infection when given with the BCSP vaccine, but not when given with the PKLPS vaccine. Trehalose dimycolate had no effect on mean CFU when given with BCSP, but incorporation of TDM resulted in a significant increase in mean CFU when given with PKLPS. Spleen weights in BCSP- or PKLPS-vaccinated mice were not different when these vaccines were combined with MPL or TDM. Because of the wide variation in the results, we could not conclude that vaccination with BCSP or PKLPS alone, or in combination with MPL altered spleen cell interleukin-1 production in B abortus-infected mice. Increased host protection as defined by decreased CFU could not be related consistently to increased BCSP- or PKLPS-specific serum IgG or IgM antibodies introduced by any of the vaccines. These results do not eliminate a role for antibodies in the protection observed.

The RH strain of Toxoplasma gondii is highly virulent; 1 infective organism is uniformly lethal for mice. Three pigs inoculated sc with 10(3) tachyzoites of the RH strain developed fever, but otherwise remained normal, and T gondii was not demonstrated in their tissues by bioassay into mice. To determine whether vaccination with the RH strain could induce protective immunity to oral challenge with T gondii oocysts, 12 pigs were divided into 3 groups (A, B, C) of 4 pigs each. Pigs in groups A and B were inoculated IM with 10(6) tachyzoites of the RH strain and 4 pigs in group C served as uninoculated controls. Except for fever, the pigs remained clinically normal after inoculation with the RH strain and T gondii was not found by bioassay in mice of tissues from 4 pigs euthanatized 64 days after inoculation. Pigs in groups B and C were challenge-inoculated orally with 10(4) (4 pigs) or 10(5) (4 pigs) T gondii oocysts 72 days after vaccination with the RH strain. The previously uninodulated pigs developed fever, anorexia, and diarrhea from 3 to 8 days after the oocyst challenge. One of the 2 pigs given 10(5) oocysts became moribund because of toxoplasmosis and was euthanatized 9 days after inoculation. Pigs vaccinated with the RH strain remained free of clinical signs after challenge with oocysts. Results of the bioassays indicated that fewer tissue cysts developed in the RH strain-vaccinated pigs than in the previously uninoculated control pigs.

Twenty-six clinically normal colostrum-fed dairy calves were allotted to 5 groups. Calves of groups 1 and 2 served as nonvaccinated controls and were challenge-exposed with variable numbers of organisms. Group-3 calves were vaccinated SC with a modified Salmonella typhimurium bacterin. The bacterin was composed of killed acid-hydrolyzed S typhimurium G30/C21 (Re-mutant) whole cells coated with alkali-hydrolyzed S typhimurium LT-2 lipopolysaccharide, as antigen, and monophosphoryl lipid A, as adjuvant. Calves of groups 4 and 5 were vaccinated with a 2% mineral oil-in-water emulsion containing lipopolysaccharide as antigen and monophosphoryl lipid A and trehalose 6-6'-dimycolate as adjuvants. Calves of groups 3-5 were vaccinated at 2 weeks of age and again at 4 or 6 weeks of age. Adverse reactions were not observed after vaccination. Calves were challenge-exposed orally at 6 or 8 weeks of age with 1.5 X 10(11) (groups 1 and 4), or 3.0 X 10(11) (groups 2, 3, and 5) colony-forming units of S typhimurium UCD 108-11. Mortality after challenge exposure was 2 of 5 group-1 calves; 4 of 5 group-2 calves; 5 of 6 group-3 calves; 1 of 5 group-4 calves; and 4 of 5 group-5 calves. Statistical difference between calves of similarly challenge-exposed groups was not evident, indicating failure of either vaccine to protect calves of this age from oral challenge exposure with virulent S typhimurium.