A cross-sectional comparative study was carried out to investigate the productive and reproductive performances of different genetic groups of crossbred cows at three different farming conditions in Bangladesh. Crossbred cows (n=90) those already completed third lactations, were selected randomly from three different dairy farms (e.g. Jarip, Mullah and Nahar) located in Chittagong, Bangladesh. ...

Using a cross-sequential design involving four birth cohorts and five measurement periods, a curvilinear relation between aging and research productivity was found for more than 1,000 academic psychologists. Productivity typically began at a low rate in the 20s, increased to a peak around age 40, then decreased in the later years. Substantial individual differences were also observed. Those who...

A preliminary national evaluation of productive life was computed from records of 11 million Holsteins. Data were a mixture of projected and completed months in milk by 7 yr of age. Data were analyzed with the animal model programs currently used for yield traits. Genetic trend for productive life was positive as a correlated response to past selection for yield and type traits. Phenotypic tren...

Contrary to the fairly established notion in the learning sciences that un-scaffolded processes rarely lead to meaningful learning, this study reports a hidden efficacy of such processes and a method for extracting it. Compared to scaffolded, well-structured problem-solving groups, un-scaffolded, ill-structured problem-solving groups struggled with defining and solving the problems. Their discu...

Two experiments examined the relation between early object name learning and the ability to represent objects by their abstract shapes. In Experiment 1, two-year-old children with productive vocabularies in the bottom 20th percentile--'late talkers'--were compared with (1) same-age children with larger vocabularies, and (2) younger children matched for productive vocabulary, on their ability to...

this study describes the management and products of the gasconne cattle in two neighbouring countries (spainand france), as a model study in trans-border breeds, analysing if they are significantly different depending on the place where they are located. fifty-seven gasconne breeders were interviewed (32 inspainand 25 infrance). the survey examined several aspects of the productive farming syst...

this study was carried out to examine the effect of post hatch fasting (phf) period with and without subcutaneous injection of 0.6 ml ca-gluconate (ca-g) on productive performance and breast muscle development in broiler chicks up to day 28 of age. weight gain (wg) and feed intake (fi) were significantly reduced and fcr was increased as phf lasted for 36 h. injection of ca-g did not improve wg ...

In 2002, a new Ural type of black-and-white breed was officially registered. Animals this have high productivity indicators, but at the same time there is decrease in productive longevity breeding stock. The conjugacy milk yield for lactation established, which allows first to carry out selection fory yield. relationship weakens with age animals and becomes negative fifth lactation. such charac...

In this paper, we estimate the profile of productivity by age through the estimation of production functions. ‘Productivity’ is defined as the average contribution of age groups to the productivity of firms. Our data are a matched employer-employee dataset covering about 70,000 firms in the late 1990’s in France. We find that productivity increases with age until age 40 and then remains stable ...