The authors reported an outbreak of infection occurring in a small poultry laying farm without obvious symptoms of sick birds. The mortality rate within a few week-period of onset was up to 50%. Post mortem examinations were conducted and the lesions were described. With the aid of bacteriological confirmation including biochemical and pathogenicity test, the cause of the disease was found to be Pasteurella multocida. None of the birds died after one-week treatment and management.

The adverse effects of Monensin sodium and Troleandomycin in commercial broiler chickens in a commercial farm, confirmed by experimentation, were exhibited as sudden onset, leg weakness, prostration, unable to stand up and death. Morbidity rate was 30%, mortality rate was over 10%. Postmortem examination of these birds showed no significant lesions.

The primary objective of this study is to determine the extent of agricultural cooperatives' contribution to fertilizer diffusion at the farm level. A systematic interview of villagers together with the observation of village behavior and attitude in rural Chiangmai form the hard core data on which the findings of this empirical study rest. Chi-square tests of independent variables have been employed to determine the relationship of agricultural cooperative membership and fertilizer adoption. None of the results is statistically significant. This implies that agricultural cooperative fails to influence fertilizer adoption in the research area. This is consistent and thus reinforced by the field observation. The failure of the agricultural cooperative in introducing fertilizer to farmers is due not only to the inefficiency of the cooperative but also the unfavorable price ratio between fertilizer and agricultural product as well as the unreliable quality of fertilizer. The field data collection was financed by an ADC research grant. The report writing has been made possible by ISEAS of Singapore.

Three groups of 20 chickens Were given Lasota strain of Newcastle disease vaccine when they were 11 days old via eye dropping. Chickens of the first group were also inoculated subcutaneously with levamisole 4.5 mg/bird and 6.75 mg/bird (10.0 mg/lb. and 15.0 mg/lb.). Serum samples were serially collected and hemagglutination inhibition (HI) titres were assay. HI titres in sera from levamisole inoculated birds were higher than those in sera collected from control birds.

Effects of levamisole dilutions on HA of Newcastle Disease virus were studied in vitro and the findings are: 1. Treatment period 4 hours (at room temperature) - 1.1 When levamisole were mixed up to make final dilutions of 0.02 and 0.05% with NDV, no effect on HA was apparent; 1.2 When the final dilutions were 0.1, 0.25, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 and 4.0%, the HA dropped significantly; 1.3 When the final dilution were 4.5 and 5.0% all HA activities of the NDV were destroyed. 2. At final dilution 0.02% levamisole did not affect the HA when the NDV were treated for 24 hours at room temperature. 3. HA activities of NDV was usually affected when NDV were treated longer than 4 hours when the final dilutions of levamisole were higher than 2.0%. Levamisole dilution should not exceed 0.1% when it is used as ND Vaccine diluent.

A radioimmunoassay for measuring serum progesterone (P), 17-hydroxyprogesterone (17-OHP) and 17-B-oestradio (E2) in buffaloes was described. One cm3 of pooled serum with three steroids added for recovery was extracted with ether and chromatographed on a celite microcolumn. The recovery of the standard P, 17-OHP and E2 was 72.9-89.6%, 77.0-97.0% and 85.5-101.3% respectively. The precision of within assay variance of these three steroids expressed as percentage of coefficient of variations was 8.2% (P and 17-OHP) and 8.3% (E2). The between assay variance was 13.2%(PT), 11.2% (17-OHP) and 12.9%(E2). The sensitivity of the assay varied between 3.5-25.0 pg. P, 4.0-25.0 pg 17-OHP and 2.5-10.0 g E2. Levels of serum progesterone, 17-hydroxyprogesterone and 17-B oestradiol were measured in the same serum samples at daily stages of the oestrous cycle in four female buffaloes; altogether there were 11 cycles. The swamp buffaloes have the normal oestrous cycles of 19-27 days. Progesterone levels in pre-oestrous-oestrous were 9.7 +-8.5 ng/100 cm3, the level beginning to rise by day 7 or 10, and reaching a peak of 38.8 +-12.2 ng/100 cm3 in 15.6 +-3.7 days of the cycle, then declining rapidly to the basal level about 4-7 days before the next oestrous cycle. The serum levels of 17-hydroxyprogesterone rose significantly in three peaks: preostrous-oestrous (21.3 +-8.3 ng/100 cm3), metoestrous (14.6+-6.6 ng/100 cm3) and dioestrous (20.2 +-8.1 ng/100 cm3). The average values in these three phases were 15.1+-7.1 ng/100 cm3, 9.7+-5.2 ng/100 cm3 and 10.6+-4.0 ng/100 cm3 respectively. The basal levels were below 5.0 ng/100 cm3. The oestradiol levels reached a peak on the day before oestrous. The average value of the peaks was 13.0+-4.0 ng/100 cm3. The duration of the peak was about four days, then it sharply declined to basal levels of 3.9+-1.0 ng/100 cm3.

Aeromonas hydrophila is a fish-pathogen microorganism. The organism could also produce diseases in reptiles, e.g. snakes and turtles, and in amphibian, e.g. frogs. The epidemic of the ulcer disease in catfishes have been studied for the last 6 months in this laboratory. The disease was observed in the fish-cultures in Rangsit, Sampran and Supanburi. The markable lesion was the center necrosis surrounded with haemorrhage. In the severe cases the flesh was sloughed and the vertebrates were exposed. The disease in the adult fishes occasionally had the primary infection in the kidney. The nodule (or nodules) was observed at the area over the anterior kidney with the characteristic of haemorrhage and then broken out to form the ulcer. In some cases the papules were developed. The mortality rate was 5-20%. Most of the organisms produced the typical lesion in fishes after I/M inoculation 24 hrs with the dosage of 8 x 10/ml. The infection of this organism was also observed in white gibbon and swine. The gibbon had the following clinical signs; lethargic, anorexia, polydipsia, diarrhea and dyspnea. The animal died 4 days after showing the signs of sickness. In the swine case, the incoordination and circular movement was observed. The post-mortem revealed meningitis. The pathology and serological studies are in progress.