Study population and sample: The study was carried out in some selected unions of Mymensingh sadar upazila under Mymensingh district. The selected unions were: Boyra, Akua, Khagdahar, Shambhuganj, Paranganj, Chor Nilakshmia. All the hatchery operators of these unions were the population of the study. In the study area, some hatchery operators earn their livelihood from hatchery. Hatchery operators were not a good number in the study area. Because one hatchery keep one or two hatchery operators for operating the hatchery. For this reason all the population of the study area was sample of the study. Samples were selected by Whole population Sample Technique. In this way 70 samples were selected for investigating their constraints experienced in the production of fish fry.
Measurement of variables In the present study, the respondents' selected characteristics viz. age, educational qualification, household size, area under hatchery operation, knowledge on hatchery management, annual income, extension media contact and organizational participation were considered as explanatory variables. Extent of the constraints experienced by the hatchery operators in the production of fish fry constituted the focus variable. Age: Age of a respondent was measured in terms of actual years from his birth to the time of interview. A score of one (1) was assigned for each year of age. It was measured in complete years as reported by a respondent.
Educational qualification Education of a respondent was measured in terms of years of schooling completed by an individual in an educational institute. If a respondent did not know how to read and write his literacy was taken as zero (0). A score of 0.5 was given to that respondent who could sign his name, only. Besides, a respondent got actual score of one for every year of schooling i.e. 1 for class one, 2 for class two and so on.
Knowledge on hatchery management For measuring hatchery management knowledge of a respondent, the researcher followed the Bloom’s Taxonomy of Cognitive Domain which was modified and revised by Anderson and Krathwohla (2000).In this case knowledge was measured by asking 10 questions. Considering the level of difficulty, different scores were assigned for the correct responses for different questions Thus, knowledge on hatchery management of the respondents could range from 0 to 28, where, 0 indicated no knowledge and 28 indicated high knowledge on hatchery management.
Annual income All the earnings of a respondent's family from agricultural income and occupational income were added to determine his gross annual income. The income was measured in taka by multiplying the quantity of those crops with its prevailing market price per unit quantity. In case of business or service, their monthly income was multiplied by twelve to determine annual income. However, unit score of one (1) was taken for every Tk. 1000/- of annual income.
Extension media contact: Extension media contact may be defined as one's extent of exposure to different extension teaching methods. Extension Media contact was computed by counting the assigned scores for each respondent on the basis of her contact with three pre-selected extension media noted in the interview schedule. The frequency of contact with an information source was classified into four categories as "frequently" occasionally", "rarely" and "not at all" and a weight of 3, 2, 1 and 0 assigned to these categories respectively. Organizational participation: Organizational participation of a respondent was measured on the basis of status of his participation and duration of participation in different organizations. Participation status score was computed as 0 for no participation, 1 for Participation as ordinary member and 2 for Participation as executive committee member.