Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
 
Articles by R.D. Rowland
Total Records ( 2 ) for R.D. Rowland
  V. L. Christensen , J.L. Grimes , R.D. Rowland and D.T. Ort
  Embryo and hatchling survival diminish as turkey breeder hens age. Recent data indicated that a chelated calcium proteinate (CCP) additive given to turkey breeder hens improved embryo survival as hens aged but did not affect shell thickness. We hypothesized that the mechanism by which this occurred may be by improved functional shell quality and its consequent effect on cardiac physiology. To test the hypothesis, CCP was supplemented to the diet of Large White turkey breeder hens for a 25 week egg production period and compared with controls without supplementation. Eggshell conductance, conductance constants, poult growth and cardiac physiology were measured at weeks 10, 18 and 25 of production. Because elevated temperatures increase heart rates and reduce heart weight and survival, half of the eggs was incubated at 37.9°C whereas the remaining eggs were incubated at 37.5°C. Embryos and poults from the CCP group exhibited increased heart weights and improved cardiac health. The hatching poults from CCP-fed hens also grew faster for the first 3 d of life. We conclude that CCP improves eggshell conductance, and the subsequent eggshell conductance constant (k) of eggs from turkey breeder hens. The change in k improved embryo cardiac health and poult BW after hatching.
  V.L. Christensen , L.G. Bagley , T. Olson , J.L. Grimes , R.D. Rowland and D.T. Ort
  Supplementing 500 ppm of a chelated calcium proteinate (CCP) to a commercial breeder diet resulted in thicker shells and improved embryo livability. The CCP diet was fed to one half of a flock of breeders on a commercial farm that was suffering shell problems, and a standard commercial diet was fed to the remaining half. Egg production, eggshell thickness, fertility and hatchability of eggs were all monitored over an 18 wk laying period. Feeding CCP increased shell thickness and reduced numbers of cull eggs after 8 wk of lay compared to the controls. When differences in eggshell thickness were seen after 10 weeks of egg production, embryo survival and cardiac physiology were examined in three trials comparing the thicker shells to thin. Thick shells (0.44 versus 0.39 mm) improved embryo survival 2% by decreasing numbers of embryos dying late in development compared to controls and affected cardiac physiology. Thus, thick shells may improve embryo viability by affecting cardiac health during the plateau stage in oxygen consumption.
 
 
 
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility