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Full-Text Articles in Life Sciences
Analysis Of Long-Term Selection (28 Generations) For Reproduction, Growth, And Carcass Traits In Swine, Wan-Ling Hsu
Analysis Of Long-Term Selection (28 Generations) For Reproduction, Growth, And Carcass Traits In Swine, Wan-Ling Hsu
Wan-Ling Hsu
The objectives were 1) to estimate responses from 28 generations of selection for increased pigs born alive (BA) with additional selection for increased 180 d weight (WT) and longissimus muscle area (LMA) and decreased backfat (BF) in the last eight generations, 2) to estimate genetic parameters for an array of traits, and 3) to investigate whether a plateau in response for BA has occurred. All lines were derived from the same Large White/Landrace composite population. Index selection for ovulation rate and embryo survival (G0-11) was initiated in L2 in 1981; L1 was selected randomly control line for L2 (G0-23). L2 …
A Survey Of The Management And Development Of Captive African Elephant (Loxodonta Africana) Calves: Birth To Three Months Of Age, Nicole L. Kowalski, Robert H.I. Dale, Christa L. H. Mazur
A Survey Of The Management And Development Of Captive African Elephant (Loxodonta Africana) Calves: Birth To Three Months Of Age, Nicole L. Kowalski, Robert H.I. Dale, Christa L. H. Mazur
Robert H. I. Dale
We used four surveys to collect information about the birth, physical growth, and behavioral development of 12 African elephant calves born in captivity. The management of the birth process and neonatal care involved a variety of standard procedures. All of the calves were born at night, between 7PM and 7AM. The calves showed a systematic progression in behavioral and physical development, attaining developmental milestones at least a quickly as calves in situ. This study emphasized birth-related events, changes in the ways that calves used their trunks, first instances of behaviors, and interactions of the calves with other, usually adult, elephants. …
Application Of Broken-Line Analysis To Assess Floor Space Requirements Of Nursery And Grower-Finisher Pigs Expressed On An Allometric Basis, Anna K. Johnson, H. W. Gonyou, M. C. Brumm, E. Bush, J. Deen, S. A. Edwards, T. Fangman, J. J. Mcglone, M. Meunier-Salaun, R. B. Morrison, H. Spoolder, P. L. Sundberg
Application Of Broken-Line Analysis To Assess Floor Space Requirements Of Nursery And Grower-Finisher Pigs Expressed On An Allometric Basis, Anna K. Johnson, H. W. Gonyou, M. C. Brumm, E. Bush, J. Deen, S. A. Edwards, T. Fangman, J. J. Mcglone, M. Meunier-Salaun, R. B. Morrison, H. Spoolder, P. L. Sundberg
Anna K. Butters-Johnson
Few issues in swine production are as complex as floor space allowances. One method for pork producers to calculate floor space allowance (A) is to convert BW into a 2-dimensional concept yielding an expression of A = k * BW(0.667). Data on ADG, ADFI, and G:F were obtained from published peer-reviewed studies. Five data sets were created: A = grower-finisher pigs, fully slatted floors, and consistent group size; B = grower-finisher pigs and fully slatted floors (group size did not need to be consistent); C = grower-finisher pigs, partially slatted floors, and consistent group size; D = grower-finisher pigs, partially …
Food-Limited Growth And Condition Index In The Eastern Oyster, Crassostrea Virginica (Gmelin, 1791), And The Bay Scallop, Argopecten Irradians Irradians (Lamarck, 1819), Michael A. Rice, Robert B. Rheault Jr.
Food-Limited Growth And Condition Index In The Eastern Oyster, Crassostrea Virginica (Gmelin, 1791), And The Bay Scallop, Argopecten Irradians Irradians (Lamarck, 1819), Michael A. Rice, Robert B. Rheault Jr.
Michael A Rice
The growth response of the eastern oyster, Crassostrea virginica, and the bay scallop, Argopecten irradians irradians, to varying degrees of food limitation was evaluated. Under conditions of low current speed, dense assemblages of shellfish can rapidly deplete ambient food concentrations, resulting in measurable effects on growth and condition index. A flume study demonstrated significant growth and condition index responses to resource competition after reductions as small as 27% in relatively high ambient food concentrations (—4.6 u.g/1 chlorophyll). Growth rates and condition index are linearly correlated with the average chlorophyll ration consumed. A field study demonstrated similar growth responses when the …
A Review Of The Factors Influencing The Growth Of The Northern Quahog, Mercenaria Mercenaria (Linnaeus, 1758), Michael A. Rice, Jan A. Pechenik
A Review Of The Factors Influencing The Growth Of The Northern Quahog, Mercenaria Mercenaria (Linnaeus, 1758), Michael A. Rice, Jan A. Pechenik
Michael A Rice
Factors affecting the growth of larval, juvenile, and adult northern quahogs, Mercenaria mercenaria, are reviewed. Larval growth is affected by temperature, salinity, current speed, dissolved oxygen concentration, and the amount of suspended sediments in the water, along with such nutritional factors as food quantity and quality. Growth of post-set juvenile and adult quahogs is similarly affected by the same physical and nutritional factors. Recent work suggests that there is a strong genetic contribution to quahog growth rate and that selective breeding programs may be useful for producing rapid growth strains. A growing body of evidence suggests that larval growth rates …