Epidemiology of Leptospirainterrogans Serovar Hardjo Infection in Cattle

The serological prevalence of Leptospira interrogans serovar hardjo (hereafter referred to serovar hardjo) infection in cattle in this present study was 30%. Water samples from stagnant water, pond water, tank water and drain water collected from the farms were positive to Leptospira biflexa (40%) . Twentyfour per cent of soil samples obtained from three different types of soil namely clay, loam and sand in the farms were also positive to Leptospira biflexa. However, serovar hardjo or other pathogenic leptospires were not isolated in the urine, soil and water samples collected in the farms. Clinical sign of leptospiral infection was not observed in the cattle on the farms. The leptospiral isolates were further characterized using bacterial restriction endonuclease DNA analysis (BRENDA), polyacrylamide gel electrophoresis (PAGE) and Western blotting. It was confirmed that the leptospiral isolates did not belong to serovar hardjo.Under experimental condition it was demonstrated that cattle are able to maintain serovar hardjo. Six female 8-months-old Kedah-Kelantan calves were used in this trial. Leptospiremia occurred as early as 7 days post-inoculation and lasted for 13 days following intra-conjunctival inoculation. Antibody against serovar lzardjo was first detected at day 7 post inoculation, then raised to a high level at day 14 post-inoculation and maintained at the same level up to 365 days post inoculation. Leptospiruria was first detected on day 49 post inoculation and maintained up to day 147 post-inoculation. Histologically serovar hardjo was detected in the renal tubule at the end of the trial using immunoperoxidase staining. No clinical signs of leptospiral infection was observed in the same animals throughout the trial. Identification of the leptospiral isolates obtained from the inoculum and urine samples of the experimental animals using bacterial restriction endonuclease DNA analysis (BRENDA) and polymerase chain reaction (peR) showed that both isolates were serovar hardjo. The study showed that serovar hardjo can survive in rain water up to 264 hours (11 days) under experimental condition. Leptospira interrogans serovar hardjo can survive up to 72 hours (3days) in diluted urine in Malaysian field condition and up to 984 hours (41 days) at 4°C. Leptospira interrogans serovar hardjo can survive in chlorinated drinking water up to 120 hours (5 days) but was killed immediately in seawater. The organism can survive in soil samples up to 144 hours (6 days) . The contaminated environment with serovar 11l1rdjo can transmit infection of the organism to susceptible animals. It is evident that serovar hardjo infection is present in cattle farms in Malaysia. Cattle in Malaysia have a potential of maintaining serovar hardjo. Leptospira interrogans serovar hardjo has been shown to survive in water and soil for a long time in Malaysian field condition and the organisms can be transmitted to susceptible animals

Pathogenecity of Salmonella enteritidis phage type 1 isolate of Malaysia in 21 day old specific pathogen free chicken

Salmonella enteritidis (SE) has always been related to subclinical infection in the chickens infected after 2 weeks of hatching. However, few pathogenic phage types were proven for their ability to manifest systemic infection and cause the organism to be shed into the surrounding environment. It was the objective of the study to determine the pathogenicity of SE Phage Type (PT) 1 in Specific-Pathogen-Free (SPF) chickens. About 93, 21 day old SPF chickens where divided into 3 groups namely the Control, SE and Mortality groups. The chickens were raised separately in caging system and given free access to antibiotic-free ration and water. The SE and Mortality groups were inoculated orally (1.0 mL) with SE PT 1 (1x108 cfu mL-1). The chickens in the SE and Control groups were sacrificed at various intervals throughout the trial. Samples were collected for bacterial isolation and histological examination. The mortality percentage of the chickens in the Mortality group was recorded. The study showed that no mortality was recorded throughout the trial in the mortality as well as the SE group. Body weight was lower in the SE group when compared to the Control group throughout the trial except at days 2, 3 and 5 post inoculation (pi) reaching its peak at day 14 pi when the SE group body weight was 26% lower than the controls. Clinical signs observed in the SE and Mortality group were represented by diarrhoea, inappetance, ruffled feather and stunted chickens while no abnormal clinical signs where recorded in the Control group. Grossly mild airsacculitis, mild peritonitis and hepatic congestion where recorded in the SE group at day 2 pi until day 5 pi while no gross lesions where recorded in the Control group. SE was first isolated in the caecum (66%) at 12 h pi. At day 1 pi SE was isolated from the caecum and spleen (33%) whilst at day 2, SE was isolated from the caecum (100%) and caecal tonsil (66%). No SE was isolated from the cloacal swabs throughout the trial. The villi height was generally lower in the SE group when compared to the Controls, however it was significantly lower (p<0.05) in the duodenum at 12 h, days 1, 3, 5, 10, 14 and 21 pi; in the jejunum at 6 h, days 2, 14 and 21 pi while in the ileum at days 1, 3 and 5 pi. The crypts depth measurement was fluctuating however it ended up by being higher in the SE group, nevertheless it was significantly lower (p<0.05) in the SE group when compared to the Control group in the duodenum at 6 h and day 14 pi in the jejunum at day 10 pi; in the ileum at 12 h pi. Histopathological changes recorded included hepatitis, congestion and focal areas of necrosis; splenitis, congestion and oedema in the adenoid sheathed arteries; congestion and areas of necrosis in the lymphoi follicles of the bursa of Fabricius; enteritis, congestion and sloughing of necrotic enterocytes in the intestinal villi with presence of bacterial clusters in the villi surface and intestinal lumen. SE rods present in the caecal tonsils were seen to be engulfed by macrophages at days 1 and 2 pi, necrosis of the enterocytes on the villi surface and infiltration of the bacteria was recorded at day 2 pi while at days 5 pi the bacteria multiplication were seen and often located upon the M-like M cells however, no actual engulfment was recorded

Influence of age, reproductive status and vulvar conformation on canine vaginal microflora.

The influence of age, reproductive status and vulvar conformation on canine vaginal microflora of dogs reared in a tropical environment was successfully determined. Vaginal swab samples were obtained from 15 intact and 15 spayed bitches from a shelter. The dogs were grouped according to age and vaginal cytological examination was conducted to determine the oestrous cycle stage of the bitch. Physical examination and images of the vulvar conformation were captured and classed into three categories (I, II and II) based on the position, size and percentage of occlusion. The effect of vulvar conformation on bacterial load was determined. Canine vaginal microflora isolated in this study is similar to that reported in temperate climates. Coagulase-positive Staphylococcus was the most common bacteria isolated from 86.7% of the bitches. All isolated bacteria were normal opportunistic microflora of the vagina. Bitches less than one-year old had a higher bacteria load, which was 50% higher than bitches above one-year old. This finding may be attributed to the differences in immunity maturity and physiological responses of the dogs. Spayed bitches have higher bacterial load compared to intact bitches in anestrus and this may be associated with the partially occluded vulvae which occurred in 87% of these bitches. Category III, which included bitches with >50% vulvar occlusion by skin folds had a higher load of bacteria (60%) compared to category I where the vulva was not occluded (33.3%)

Disease detection of brucellosis in goat population in Negeri Sembilan, Malaysia

A serological study of brucellosis in goats caused by Brucella melitensis was conducted in the state of Negeri Sembilan, Malaysia. A total of 771 serum samples were collected from seven districts namely Rembau, Jelebu, Kuala Pilah, Seremban, Port Dickson, Jempol, and Tampin. At least two farms were selected and a minimum of 100 serum samples were collected from each district. All sera were tested for brucellosis using the Rose Bengal plate test (RBPT) and complement fixation test (CFT). In this study, only Rembau and Kuala Pilah showed seropositivity for B. melitensis with RBPT and CFT at 1.0 and 2.5%, respectively. The CFT was more sensitive than the RBPT because the serum antibodies against B. melitensis detected by CFT were twice higher than that detected by RBPT. As suggested by the Office International des Epizooties OIE, CFT was used as a confirmatory test for brucellosis. This test is also recommended as a prescribed test for international trade and is used in the control and eradication programmes

Isolation and identification of Riemerella anatipestifer from ducks in Malaysia

Riemerella anatipestifer is the primary etiological agent of contagious septicemic diseases among ducks. The study is the first atempt to isolate and identify R. anatipestifer from ducks in Malaysia. In this study, ten diseases Khaki-Campbell ducks and forty healthy Khaki-Campbell ducks were selected. A pharyngeal swab was collected from each selected ducks. One strain of R. anatipestifer was successfully isolated out of the ten diseased ducks and identified using conventional biochemical tests. R. anatipestiferwas isolated from the healthy ducks. The R. anatipestifer isolate was then subjected to antibiotic sensitivity testing using Kirby-Bauer method. The sensitivity of R. anatipestifer to penicillin G. enrofloxacin, oxytetracycline, gentamicin, neomycin, and ceftiofur was determined. R. anatipestifer was found to be highly sensitive to enrofloxacin, oxytetracycline and neomycin, intermediately sensitive to gentamicin and resistant to penicillin G and ceftiofur

Pathogenicity of Salmonella enteritidis phage types 6A and 7 in experimentally infected chicks

Pathogenicity of Salmonela enterica serovar enteritdis (S.E) phage types (PTs) 6A and 7 were determined in oraly inoculated newly hatched specific pathogen fre (SPF) chicks. Clinical signs and mortality were observed daily. Body weights, bacterial isolation, gros lesions and histological lesions were recorded on days 1, 3, 5, 7, 14 and 21 post inoculations (pi). Out of 15 newly hatched SPF White Leghorn chicks, five chicks were randomly separated to confirm the SPF status of the chicks before inoculation. The remaining chicks were divided into thre sacrificed groups (A, B and C) of 30 chicks each and their respective thre mortality groups (MA, MB and MC) of 20 chicks each. Groups A and MA, and groups B and MB were inoculated oraly with 0.1mL containing 107 cfu of SE PT6A (UPM-0527) and SE PT7 (UPM-0530), respectively. The un-inoculated groups C and MC served as negative controls. Chicks in groups A and B showed clinical signs of depresion, anorexia, rufled feathers, vent pasting and diarhea starting from day 1 pi. Lifting of wings from thorax was observed in group A and B from day 1 and 5 pi, respectively. There was significant diference (p<0.05) in body weight gain among the inoculated and the control groups on days 14 and 21 pi. Growth index values were 0.035, 0.036 and 0.037 for groups A, B and C, respectively. Mortality of 20% was recorded only in MA group. Gos lesions of unabsorbed yolk, airsaculits, fibrinous pericardits, fibrinous perihapatis, enlarged kidneys, splenomegaly and dehydration were observed in about 15% of sacrificed chicks in group A and 10% in group B. Mild to moderate lesions were observed under microscope. Salmonela was isolated from the cultured samples of group A and B throughout the experiment period with the individual variation of chicks and samples. It was concluded that newly hatched SPF chicks are susceptible to PT6A and PT7 infections. These SE PTs are mild to moderately pathogenic for SPF chicks. SE PT6A is more pathogenic than SE PT7

Antibacterial activities of sea cucumber (Holothuroidea) in poultry.

The antibacterial activities of sea cucumber (Holothuroidea) were studied. Three commercialized sea cucumber products and one dried sea cucumber were tested for antibacterial activities against six clinical isolates of common pathogenic bacteria causing diseases in poultry using Disc Diffusion Method (Kirby-Bauer Method). Only one commercial product; “Gamat Gel” produced inhibition zones towards 5 tested bacteria namely Escherichia coli, Salmonella sp., Pasteurella multocida, Staphylococcus aureus, and Streptococcus sp. in the initial susceptibility test. The biggest inhibition zones were produced against Pasteurella multocida, while smallest inhibition zones were produced against Streptococcus sp. No inhibition zone was produced against Pseudomonas aeruginosa. The determination of Minimal Inhibitory Concentration (MIC) of the Gamat Gel was carried out. It was found that the MIC value for all test bacteria were more than 1/12

A review of the epidemiology and control of brucellosis in Malaysia

The presence of brucellosis in large ruminants and pigs in Malaysia was confirmed by the isolation of Brucella abortus in 1950 and Brucella suis in 1963, respectively. Subsequently, brucellosis was detected in humans (1980), dogs (1982) and sheep(1991). The National Programme for 'The Area-wise Eradiction of Bovine Brucellosis 'which came into effect in 1979 had reduced the prevalence of bovine brucellosis in Malaysia from 3.3% in 1979 to 0.23% in 1988. It was then envisaged that by 1995 bovine brucellosis in Malaysia had been eradicted. However, the prevalance of brucellosis in cattle was reported to be high (<2%) again (Anon,2005). In the state of Pahang, there was a surge in prevalence from 0.2% in 1996 to 13% in 1998 but was brought down to 1.8% in 2005 by stringent testing, culling and vaccination. The success of the eradiction programme in the later phase proved to be difficult due to the remote geographical distribution of the animals, the extensive farming system being practised and the education and social status of the farmers. In the later phase of the programme, it was difficult to detect infected animals in the herds as the prevalence of infection was very low. It therefore, became necessary to test every animal so as not to miss the few inapparent carrier animals. For this, the enzymelinked immunosorbent assay was a useful test and was included, in addition to the Rose Bengal plate test (RPBT), to complement fixation test (CFT) and the Milk Ring Test (MRT)in the screening and diagnosis of brucellosis. Bacterial culture and isolation of suspected cases of bovine brucellosis (abortion, retained placenta) were additional measures undertaken to detect animals

Antimicrobial activities of some culinary spice extracts against Streptococcus agalactiae and its prophylactic uses to prevent streptococcal infection in red hybrid tilapia (Oreochromis sp.)

The extracts of ten culinary spices were screened to identify their antimicrobial activities against Streptococcus agalactiae by using disk diffusion assay. Only Cinnamomum verum, Allium sativum Linn, Eugenia caryophyllus and Thymus vulgaris displayed antimicrobial activity. The bark C. verum extract displayed the highest antimicrobial activity with a 18 mm inhibition zone. The minimum inhibitory concentration (MIC) values for spice extracts were determined by utilizing the agar diffusion method. The lowest MIC value with high efficacy against S. agalactiae was 0.15 mg\mL, which was obtained from C. verum extract. The median lethal dose (LD50) of S. agalactiae to tilapia fingerlings was measured to be 1.56×105 CFU/mL. The in vivo antimicrobial effect of C. verum was tested by feeding tilapia fingerlings fish feed supplemented with different ratios of C. verum extract and bark powder for 17 days after experimentally injecting the fish with S. agalactiae intraperitoneally (IP). The mortality was significantly lower (p<0.05) in the fish fed on feed supplemented with bark C. verum extract with a ratio of 3:26 (w/w) compared to other groups. These results indicated that the C. verum bark extract supplement is promising as a prophylactic against tilapia streptococcosis and for fish health improvement