Phontip Sirivan Urasri Tantaswasdi Surasak Chuenchai

National Institute of Animal Health, Department of Livestock Development,

Kasetklang, Jatuchak, Bangkok 10900.

Duck hepatitis virus [DHV] was isolated from 9- to 14-day-old ducklings from Chonburi and Rayong Provinces. The ducklings had an acute fatal disease, the clinical signs and lesions of which were similar to those of duck virus hepatitis. The virus was isolated by inoculating 20% liver suspension into embryonated chicken and duck eggs, and duck embryo liver cells. The isolated virus was inoculated into unvaccinated ducklings and into ducklings vaccinated with duck virus hepatitis vaccine. Chicken embryos developed both hemorrhage and oedema, while duck embryos showed only hemorrhage. A cytopathic effect was observed in primary culture of embryo liver cells. The experimentally vaccinated ducklings were protected but the unvaccinated ducklings were susceptible, with 60-80% mortality. As in the field cases, opisthotonic signs were observed, death was rapid, and ecchymotic hemorrhage was found in the liver. Identification of the isolated virus with reference antisera in a neutralization test confirmed that it was DHV.

Key words : Duck hepatitis virus, isolation, ducklings.

Vimol Youyuentong Lawan Pemayodhin Vallee Tishyadhigama

Small Animal Veterinary Service, Veterinary Service Division.

Livestock Department. Bangkok 10400

The effect of zinc on parakeratosis was studied in 90 typical skin lesion characterized swine which consist of gilts, lactating sows and boars. The animals were divided into 2 groups. Group 1 , comprising 60 swine was treated by adding 100 ppm of zinc oxide in feed for 40 days. Group 2 [control group] of 30 swine was not supplemented with zinc oxide in the same feed.

After 40 days, blood samples from these 2 groups were collected and analyzed for serum calcium and zinc levels. The average value of serum calcium level in group 1 was 9.31+0.03 mg/dl, and the control group was 9.41+0.04 mg/dl. There was no significant difference of serum calcium level between both groups [p>0.01]. In conclusion, supplementation of zinc at 100 ppm in feed had no effect on calcium level in the blood serum. The average zinc level in serum was 85.64+1.48 ug/100 ml group, and 73.92+2.10 ug/100 ml in group 2. The zinc level in serum between the two groups were statistically significant different [p>0.01]. Histologically, skin condition of 80% of group 1 was completely recovered, while the other 20% was almost normal. There was no change in skin condition of group 2. This result suggested that parakeratosis can be treated by adding 100 ppm of zinc as zinc oxide in feed for 40 days.

Key words : Zinc, parakeratosis, pig

Ratchanee Atthi Vuthiporn Rungvetvuthivitaya Niteth Lerlimchalalai

Veterinary Biologics Center, Veterinary Biologics Division,

Pakchong, Nakhonrathasima 30130

A large scale production [about 100 litres] of haemorrhagic septicaemia oil adjuvant vaccine was developed. Broth bacterin of Pasteurella multocida, serotype 6:B or B:2 which cultured in tryptose phosphate broth and inactivated with 0.3% formalin [v/v] were emulsified with either of the two formulations of oil adjuvants, Montanide ISA 70, or Marcol 52 with Arlacel A and Tween 80. Emulsion property and potency of the vaccines were tested. Mixing of broth bacterin with either of the oil adjuvant within 5 minutes and homogenized for 25 minutes was shown to be most appropriate. The oil emulsion vaccines were efficacious against active mouse protection test and challenge test in cattle. This technique is convenient for a large scale production of haemorrhagic septicaemia vaccine.

Key words : haemorrhagic septicaemia, oil adjuvant vaccine, large scale production.

Petcharat Sakdinun Satis Pholpark

Northeast Regional Veterinary Diagnostic Center [NERVDC],

Thaphra, Moeng, Khonkaen 40260

This report reviewed fourty-four cases of suckling foals submitted to NERVDC Khonkaen for diagnosis during 1990 to 1997. The diagnosis was related to clinical symptoms and bacteriological findings. Gastrointestinal symptomas were the most common clinical feature of all cases followed by respiratory, lameness and nervous symptoms. Single or multiple specimens of the following organisms: E.coli,Klebsiellapneumoniae, Pseudomonasaeruginosa, Streptococcus spp., Corynebacterium spp.or Salmonella spp. were isolated from twenty-eight cases with gastrointestinal problems while E. coli,Klebsiella pneumoniae, Pseudomonas aeruginosa, Rhodcoccus equi and Streptococcus spp. were isolated from 9 cases with respiratory problems. E. coli and B-Streptococcus spp. were isolated from five cases with lameness problems and B-Streptococcus spp. and Clostridium tetani were isolated and confirmed from each of the two cases with nervous symptoms. Most of the isolated bacteria were gram negative rather than gram positive bacteria. The particular infections are age-related, ie.animals of different ages are susceptible to different bacterial infections.

Key words : bacterial infections, suckling foals, clinical symptoms

Apirom Charoenchai 1 Manvika Pholpark 1 Smarn Tesana 2

1Northeast Regional [Veterinary Diagnostic Center Thaphra, Khonkaen 40260

2Faculty of Medicine, Khonkaen University, Khonkaen 40000

Lymnaea[Radix] auricularia rubiginosa [Michelin,1831] was surveyed in 54 water reservoirs of 18 districts in Amphoe Muang, Khonkaen province between February and May 1994. Lymnaeid snails were found in 20 water reservoirs of which 16 contained clear water, 2 had turbid water and 2 water reservoirs received drainage water from Khonkaen Town. Two thousand four hundred and eight of L. auricularia rubiginosa were collected and examined for cercariae by shedding and crushing Trematode larvae infection were found in 163 [6.77%] snails and some of them were infected with morethan one cercarial species. Ninety nine snails [4.11%] were infected with Echinostoma spp., while the mixed infection of Echinostoma spp. with Fasciola gigantica or Schistosoma spp. were found in 5 snails [0.21%] and snails [0.08%], respectively. Single infections of F. gigantica, Schistosoma spp. or unidentified species were in 1 snail [0.04%], 19snails[0.79%] and 37 snails[1.54%], respectively. The mean size of infected snails was 13.48+3.25 mm [6.20-22.60 mm.] whereas that of sampled snails was 13.46+3.65 mm [4.00-26.55 mm.]. The infection rate between young snail [length<15 mm] and adult snail [length>15mm] were not significant different [p>0.05]. The infection rate of snail which lived in drainage water, clear water and turbid water were 18.18%, 6.57% and 4.23%, respectively. The infection rate of snail which lived in clear water when compare with those lived in turbid water were also not significant different [p>0.05]. But the infection rate of snail which lived in clear water and turbid water when compare with those lived in drainage water were significant different [p<0.05]. The water plants harboring snails in water reservoirs were creeping water primose [Jusstaea repens], water lily [Nymphaea sp.], water hyacinths [Eichornia crassipes] and Hymenachne pseudointerupta and Cypenus spp.

Key words : Trematode larvae,Lymnaea [Radix] auricularia rubiginosa, water reservoir

Malee Teeranusonti 1 Suchin Uttasart 1 Chit Sirivan 2

1 Toxicology and Biochemistry section, National Institute of Animal Health, Chatuchak, Bangkok10900

2 Epidemiology section, National Institute of Animal Health, Chatuchak, Bangkok10900

Ninety seven poultry and seventy eight swine feed samples were collected from various farms of eight provinces in 1 , 2 and 7 regions of Thailand. Samples were extracted and analyzed for organophosphate insecticides by gas chromatograph. The residue of organophosphate insecticide group was found in 63.92% of poultry feed and 47.44% of swine feed. However, the level of residue in poultry and swine feed were lower than the maximum residue limits of FAO/WHO recommendation. Dichlorvos residue, the organophosphate insecticide was most often found in poultry and swine feed from these three regions.

Key words : Organophosphate, insecticide residue, poultry feed, swine feed

Duangjai Suwanchareon Nittaya Intarasri Chit Siriwan

National Institute of Animal Health, Kasetklang, Chatuchak, Bangkok 10900

A total of 555 swine serum samples from the farms with history of abortion in Nakhon Pathom, Chachoengsao and Saraburi provinces were tested for leptospirosis antibodies using microscopic agglutination test [MAT]. The positive sera to leptospirosis antibodies by MAT from Nakhon Pathom, Chachoengsao and Saraburi were 17.4% [33/190], 1.7% [3/180] and 10.8% [20/185], respectively. Most of the positive sera had the titer of 1:400 to 1:800. The highest antibody titer at 1:32,00 was detected from the sows in Nakhon Pathom. The positive sera, were positive to L. bataviae [8.6%], L. canicola [0.7%], L. pomona [0.4%], L. icterohaemorrhagiae and L. akiyami A [0.2%]

Key word :Antibodies, Leptospirosis, Microscopic agglutination test [MAT], swine

Sujira Parchariyanon Sudarat Damrongwatanapokin Wasana Pinyochon

National Institute of Animal Health, Kasetklang, Chatuchak, Bangkok, 10900, Thailand.

Abstract

Neutralizing peroxidase linked assay [NPLA] using monoclonal antibody [Mab] was developed for detection of swine fever virus [SFV] antibodies in swine sera. Staining positive cells in the microplates using Mab instead of polyclonal antibody in NPLA yielded a better positive reaction. Four hundred and fourteen swine sera from the Central part of Thailand were examined for SFV antibodies by NPLA and neutralizing immunofluorescence [NIF] test. The NPLA had a sensitivity of 97.6% and a specificity of 83.3% when compared with the NIF test. There was no significant difference [P>0.05] between the two test and the correlation coefficient [ r = 0.927 and r 2 = 0.86 ] was statistically significant [p<0.001].

Key word : neutralizing peroxidase linked assay, swine fever

Nopporn Sarataphan

Parasitology Section, National Institute of Animal Health,

Kaset Klang, Chatuchak, Bangkok 10900, Thailand

The objective of this study was to collect and evaluate the ability of dung beetles

[Coleoptera : Scarbaeidae] to disperse fecal masses for biological control of bovine gastrointestinal nematodes. Investigations of dung beetles were performed in 16 provinces of Thailand between 1993 to 1997. Fifteen species of dung beetles were performed in this investigation belonging to family Scarbaeidae, Histeridae and Aphodiidae. Onitis spp. was found the dominant species with widely distribution and followed by Onthophagus seniculus Fabr, which only in the northeastern part of Thailand. Number of Onitis spp. and Onthophagus seniculus Fabr. to disperse [above 90%] of 100 and 200 g buffalo fecal masses in one night was 10 and 20, respectively. The result demonstrated that 10 adults of Onitis SPP. and 20 adults of Onthophagus seniculus Fabr. were able to cause reduction in larval hatching from each 100 g of cattle feces contaminated with eggs of Bunostomum phlebotomum, Trichostrongylus SPP., Cooperia SPP. and Oesophagostomum SPP. average 95.9 and 89%, respectively in laboratory as well as 96.8% and 91.3% outside laboratory conditions.

Key words : dung beetles, biological control, gastrointestinal namatode, cattle

Division of Artificial Insemination, Department of Livestock Development,

Pyathai Road, Bangkok 14000

Abstract

Sex determination of bovine embryos before transfer was studied by using a simplified cytogenetic technique which was successfully established for sexing mouse and ovine embryos. The culture period of bovine embryos with colcemid was adjusted in order to obtain the shortest duration that could produce enough metaphase spreads to allow accurate sex chromosome identification. The results indicated that only 2 hour-culture-period of bovine embryos with colcemid was sufficient to produce enough metaphase spreadsf or sex chromosome identification. This technique required less than 4 hours for sexing bovine embryos.