The report summarizes a one year period of investigation of death losses in West Malaysian livestock. Lesions and etiological agents are mentioned for cattle, sheep, goats, swine, poultry and companion animals as well as some miscellaneous species. Special observations related to a common paramphistome induced hepatic biliary infestation in cattle, a serious malignant head catarrh outbreak in which possible cattle to cow aerosol transmission occurred. Trismus observed in some cattle with malignant head catarrh was associated with arteriolitis and ganglioneuritis of the V cranial nerve. Parasitic, bacterial, viral toxic and neoplastic diseases are recorded in the various species. The occurrence of fatal chronic fluorosis in laboratory guinea pigs and cerebral nematodiasis in a Thoroughbred racehorse are documented.
An experimental oil emulsion Newcastle disease vaccine was evaluated for its efficacy in broiler chickens. A group of chickens vaccinated at one day old with a live lentogenic Newcastle disease vaccine and subsequently revaccinated at three and eight weeks old with the experimental oil emulsion vaccine showed satisfactory haemagglutination inhibition antibody response which persisted for 18 weeks. Between 90 and 100 per cent of the vaccinated chickens were protected when challenged with the velogenic viscerotropic Newcastle disease virus. Although the vaccinated chickens were protected against clinical disease, virus could be isolated from a number of birds. By day 10 to 12 after challenge all the chickens were free from Newcastle disease infection.
This paper reports the experimental transmission of a bird parasite into jirds. Infective larvae of Cardiofilaria nilesi obtained from laboratory colonized Coquillettidia crassipes mosquitoes which had fed on an infected chicken were inoculated subcutaneously into jirds. The number of larvae per jird varied from 10 to 228. Microfilaraemia appeared 22 to 89 days after inoculation of the infective larvae. Experiments were carried out with 24 jirds through six generations extending over a period of 22 months and 17 produced patent infections. At present 8 infected jirds are being maintained in the laboratory; their patent periods ranging from 6 to 13 months. However, the longest patent period observed was about thirteen months. The percentage of adults recovered in autopsied jirds ranged from 0 to 40 with an average of 16. The chicken showed a microfilarial periodicity with the peak microfilarial density around 2200 hours. However, in jirds there was a change in sub-periodicity. This model in the jird may be very useful for the screening of filaricides and in immunological work.
Eight-five clinical and 15 poultry isolates of Campylobacter species were characterised by biotyping, serotyping and by using a radiolabelled DNA probe. A total of 80% of the isolates from both sources were identified as C. jejuni. Also amongst the clinical strains were 5 c. jejuni subsp. doylei, 7 C. coli, 3 C. lari and 8 were untypable. The similarity in the distribution of C. jejuni in the clinical and poultry isolates adds credibility to published reports of chickens being the most common source of Campylobacter infections. Although the gold standard for identification of C. jejuni is the DNA probe, serotyping is more discriminating while biotyping is the most feasible method in most laboratories.
Since 1954, avian mycoplasmosis has been considered a significant problem in chicken flocks in Japan and in other Asian countries. In Japan, Mycoplasma gallisepticum (MG) and M. synoviae (MS) infections were confirmed aetiologically in chicken flocks affected with respiratory disease or synovitis in 1962 and 1973, respectively. In other Asian countries, including Indonesia, the People's Republic of China, Korea, Malaysia, the Philippines, Taipei China and Thailand, the occurrence of mycoplasmosis in chicken flocks has been recognised serologically or aetiologically. Adverse atmospheric and environmental conditions, in addition to mixed infections of bacterial or viral origin, play an important role in the spread of MG and MS within chicken flocks or in the induction of clinical respiratory mycoplasmosis. Serological tests are important in determining and monitoring the mycoplasmal infection status of chicken flocks. The establishment of mycoplasma-free breeding stocks is recognised as essential for the control of avian mycoplasmosis. To eliminate the transmission of MG to the egg, treatment of infected breeder flocks or their progeny with anti-mycoplasmal antibiotics was effective in considerably reducing the infection rate but not in entirely eliminating MG infection. The preincubation heat treatment of chicken hatching eggs has proved an effective procedure for establishing MG- and MS-free breeding stocks in Japan. Vaccination against MG infection has been practised successfully in Japan and other countries.
Enterococcus species isolated from poultry sources were characterized for their resistance to antibiotics, plasmid content, presence of van genes and their diversity by randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). The results showed that all isolates were multi-resistance to the antibiotics tested. Ampicillin (15/70) followed by chloramphenicol (37/70) were the most active antibiotics tested against the Enterococcus spp. isolates, while the overall resistant rates against the other antibiotics were between 64.3% to 100%. All vancomycin-resistant E. faecalis, E. durans, E. hirae and E. faecium isolates tested by the disk diffusion assay were positive in PCR detection for presence of vanA gene. All E. casseliflavus isolates were positive for vanC2/C3 gene. However, none of the Enterococcus spp. isolates were positive for vanB and vanC1 genes. Plasmids ranging in sizes between 1.1 to ca. 35.8 MDa were detected in 38/70 of the Enterococcus isolates. When the genetic relationship among all isolates of the individual species were tested by RAPD-PCR, genetic differences detected suggested a high genetic polymorphisms of isolates in each individual species. Our results indicates that further epidemiological studies are necessary to elucidate the role of food animals as reservoir of VRE and the public health significance of infections caused by Enterococcus spp.
A new virus named Sitiawan virus (SV) was isolated from sick broiler chicks in chicken embryos. The virus replicated well with cytopathogenic effect (CPE) in the chicken B-lymphocyte cell line LSCC-BK3. The virus was an enveloped RNA virus of approximately 41 nm in size with hemagglutinating activity (HA) to goose erythrocytes. It was cross-reactive with Japanese encephalitis virus (JEV), a member of flaviviruses by HA inhibition tests but not by cross-virus neutralization tests. The cDNA fragment of NS5 gene was amplified with primers corresponding to NS5 gene of flaviviruses. The nucleotide sequences were 92% homologous to Tembusu virus, a member of the mosquito-borne virus cluster of the genus Flavivirus. In cross-neutralization tests with Tembusu virus, antiserum to SV did not neutralize Tembusu virus, and antiserum to Tembusu virus neutralized more weakly to SV than against homologous virus. These results indicate that SV is a new virus which can be differentiated serologically from Tembusu virus but is otherwise similar with respect to nucleotide sequence. The virus causes encephalitis, growth retardation, and increased blood glucose levels in inoculated chicks.
Ten strains of Salmonella weltevreden isolated from poultry sources were examined and found to contain plasmid DNA ranging in size from 1.8 to 68.5 MD. All isolates were susceptible to carbenicillin, cephalothin, ceftriazone, gentamicin, kanamycin and nalidixic acid, but resistance to bacitracin (100%), penicillin G (100%), rifampicin (100%), sulphamethoxazole (100%), cefuroxime (80%) and tetracycline (60%) was recorded. The 55 MD plasmid of strain SW5 determined resistance to penicillin G and tetracycline, which was transmissible to the E. coli K12 recipient at a frequency of 3.52 x 10(-5) transconjugants per input donor cell. The results of arbitrarily primed polymerase chain reaction (AP-PCR), using two 10-mer oligonucleotides and PCR-ribotyping to differentiate between the ten strains of S. weltevreden were compared. The strains were separated into ten different genome types by AP-PCR but were indistinguishable by PCR-ribotyping. These results suggest that poultry may constitute a reservoir for disseminating antibiotic resistance and that AP-PCR may be a valuable tool for epidemiological studies.
A Chicken anemia virus has been isolated from a chicken flock in Harbin of China. The genome of the ivrus was cloned through polymerase chain reaction(PCR) and sequence of the genome was analyzed. The cycle genome is made of 2298 base pairs including three overlapping open reading frames(vp1, vp2, vp3) and a regulative region. Comparing sequence of the genome through BLAST in GenBank, this sequence exhibits 96.9% identity with other genome of CA Vs and least. Multiple alignment of this genome of this virus, 26p4, strain isolated in Germany, strain isolated in Malaysia and Cux-1 found that this sequence exhibits 98.2% (42/2298), 98.2% (42/2298), 96.9% (72/2298) and 97.5% (60/2319) identify with them, respectively. A new CAV strain was isolated and it has better identify with CAV isolated in Europe countries than is Asia country Malaysia. Multiple alignment of VP1, VP2, VP3 of 26p4, strain isolated in Germany, strain isolated in Malaysia, Cux-1 and strain isolated in Harbin of China found the VP2 the most conservative.
The effects of early age feed restriction and heat conditioning on heat shock protein (HSP) 70 expression, antibody production, resistance to infectious bursal disease (IBD), and growth of heat-stressed male broiler chickens were investigated. Chicks were divided into 4 groups: 60% feed restriction on d 4,5, and 6 (FR); exposure to 36 +/- 1 degrees C for 1 h from d 1 to 21 (HT); combination of FR and HT (FRHT); and control. From d 35 to 50, heat stress was induced by exposing birds to 38 +/- 1 degrees C and 80% RH for 2 h/d. On d 36, each bird was administered 10 times the normal dose of live IBD vaccine. After heat exposure, the FRHT birds had higher HSP 70 density (d 41) and weight gain (from d 35 to 49) and lower bursal histological score (BHS) (d 51) than their HT and control counterparts. The HSP 70 expression and BHS of FR birds were not significantly different from those of the other 3 groups during the heat exposure period. Heat shock protein 70 and BHS data were negatively correlated (r = -0.33, P = 0.0008). We concluded that FRHT could improve weight gain and resistance to IBD in male broiler chickens under heat stress conditions. The improved heat tolerance and disease resistance in FRHT birds could be attributed to better HSP 70 response.