scholarly journals Transferrin polymorphisms and growth rate in Rhode Island Red, crossbred and native chickens

1991 ◽  
Vol 4 (3) ◽  
pp. 231-234 ◽  
Author(s):  
S. Zaman ◽  
A. Ali ◽  
M. O. Faruque ◽  
A. K. F. H. Bhuiyan
Keyword(s):  
Growth Rate ◽  
Rhode Island ◽  
Native Chickens

Estimating growth and mortality of juvenile winter flounder, Pseudopleuronectes americanus, with a length-based model

2001 ◽  
Vol 58 (11) ◽  
pp. 2233-2246 ◽  
Author(s):  
Allison K DeLong ◽  
Jeremy S Collie ◽  
Carol J Meise ◽  
J Christopher Powell
Keyword(s):  
Growth Rate ◽  
Rhode Island ◽  
High Growth ◽  
High Growth Rate ◽  
Narragansett Bay ◽  
Winter Flounder ◽  
Individual Growth ◽  
Pseudopleuronectes Americanus ◽  
Maximum Likelihood Methods ◽  
Decreasing Functions

This study quantifies the combined effects of density and environmental factors on young-of-the-year (YOY) winter flounder (Pseudopleuronectes americanus) in Narragansett Bay, Rhode Island. We used a length-based model to estimate growth and mortality rates from June to October each year from 1988 to 1998. In this model, mortality and growth rates are decreasing functions of length and there is variability in individual growth. Maximum-likelihood methods were used to fit the model to length-frequency data collected by the Rhode Island Division of Fish and Wildlife beach-seine survey in Narragansett Bay during the study years. The monthly mortality rate was density dependent and was positively related to temperature. Growth rate was negatively related to density. There was a significant decline in YOY winter flounder abundance during the period of study. The most recent year of the study, 1998, had the lowest density, lowest mortality, low summer temperature, and high growth rate. Thus, growth and mortality during the juvenile stage do not appear to be limiting the recovery of this depleted winter flounder population.

scholarly journals Qualitative Traits and Genetic Characterization of Native Chicken (Gallus gallus domesticus) in Selected Areas of Eastern and Western Samar, Philippines

2020 ◽  
pp. 52-70
Author(s):  
Cyrill John Godinez ◽  
Masahide Nishibori ◽  
Dinah Espina
Keyword(s):  
Rhode Island ◽  
The Philippines ◽  
Plumage Color ◽  
Qualitative Traits ◽  
Genetic Groups ◽  
Red Junglefowl ◽  
Commercial Line ◽  
Native Chicken ◽  
Chicken Breeds ◽  
Native Chickens

The Philippines has a number ofchicken genetic groups, mostly of non-descript and indigenous type. In view of the need to expand the information on native chicken diversity, this study was conducted to identify distinct qualitative traits and estimate genetic diversity and relationship among native chicken populations in selected areas of Eastern and Western Samar, Philippines. A total of 100 native chickens were qualitatively analyzed using a non-parametrictest, and 43 generated mtDNA sequences were used in the genetic analysis. Results revealed significantly different distributions of plumage color among male native chickens and shank color in female native chickens (p<0.05). The occurrence of plumage pattern, earlobecolor and shank colorfor male native chickens and plumage color, plumage pattern, and earlobe color for female native chickens across Samar Island is not different (p>0.05). The genetic relationship showed 41.2% native chicken populations clustered to a group shared by Red junglefowl and native chicken, 29.4% clustered to a group closer to White Leghorn, and White Plymouth Rock chicken breeds, 17.6% clustered to a group shared by G, g. spadiceus and a commercial line, and 11.7% clustered to a group closer to Rhode Island Red and a commercial egg layer line. Samar native chickens had red (wild-type, e+) laced (lg) and brown (eg) pencilled (Pg) plumage in rooster and hen, respectively. The phenotypic and genetic information concluded that there is considerable diversity of native chickens in Samar, Philippines. There is a tremendous opportunity to work with larger sample size in the areas where a number of indigenous chickens have notyetbeen characterized.

scholarly journals Genetic Effect and Growth Curve Parameter Estimation under Heat Stress in Slow-Growing Thai Native Chickens

2021 ◽  
Vol 8 (12) ◽  
pp. 297
Author(s):  
Wuttigrai Boonkum ◽  
Monchai Duangjinda ◽  
Srinuan Kananit ◽  
Vibuntita Chankitisakul ◽  
Wootichai Kenchaiwong
Keyword(s):  
Growth Rate ◽  
Heat Stress ◽  
Growth Performance ◽  
Growth Curve ◽  
Growth Rates ◽  
Stress Effect ◽  
Gompertz Function ◽  
Chicken Breeds ◽  
Native Chickens ◽  
Slow Growing

Heat stress is becoming a major problem because it limits growth in poultry production, especially in tropical areas. The development of genetic lines of Thai native chickens (TNC) which can tolerate the tropical climate with the least compromise on growth performance is therefore necessary. This research aims to analyze the appropriate growth curve function and to estimate the effect of heat stress on the genetic absolute growth rate (AGR) in TNC and Thai synthetic chickens (TSC). The data comprised 35,355 records for body weight from hatching to slaughtering weight of 7241 TNC and 10,220 records of 2022 TSC. The best-fitting growth curve was investigated from three nonlinear regression models (von Bertalanffy, Gompertz, and logistic) and used to analyze the individual AGR. In addition, a repeatability test-day model on the temperature-humidity index (THI) function was used to estimate the genetic parameters for heat stress. The Gompertz function produced the lowest mean squared error (MSE) and Akaike information criterion (AIC) and highest the pseudo-coefficient of determination (Pseudo-R2) in both chicken breeds. The growth rates in TSC were higher than TNC; the growth rates of males were greater than females, but the age at inflection point in females was lower than in males in both chicken breeds. The THI threshold started at 76. The heritability of the AGR was 0.23 and 0.18 in TNC and TSC, respectively. The additive variance and permanent environmental variance of the heat stress effect increased sharply after the THI of 76. The growth rate decreased more severely in TSC than TNC. In conclusion, the Gompertz function can be applied with the THI to evaluate genetic performance for heat tolerance and increase growth performance in slow-growing chicken.

RESPONSE OF WHITE LEGHORN AND RHODE ISLAND RED BREEDER HENS TO DIETARY DEFICIENCIES OF SYNTHETIC VITAMINS. 1. EGG PRODUCTION, HATCHABILITY AND CHICK GROWTH

1979 ◽  
Vol 59 (3) ◽  
pp. 561-567 ◽  
Author(s):  
S. LEESON ◽  
B. S. REINHART ◽  
J. D. SUMMERS
Keyword(s):  
Adverse Effect ◽  
Growth Rate ◽  
Rhode Island ◽  
Soybean Meal ◽  
Egg Production ◽  
Control Diet ◽  
White Leghorn ◽  
Chick Growth ◽  
Breeder Hens ◽  
Single Comb

Thirty-week-old purebred strains of Single Comb White Leghorn (WL) and Rhode Island Red (RIR) breeder hens were offered a control corn-soybean meal diet or the control diet with one of the following vitamins omitted from the supplement: biotin, B12, E, folacin, niacin, pantothenate and riboflavin. For each strain, four randomly distributed cages of four birds were offered each diet. Birds were inseminated weekly with 0.05 ml of pooled White Leghorn (WL) semen. Egg production, fertility and hatchability were recorded. After 15 wk, the vitamins omitted were added to the diets, and observations continued for a further 5 wk. With the exception of biotin, each unsupplemented diet had an adverse effect on egg production of RIR (P < 0.05), although few significant effects were observed with WL. Diet had no effect on fertility. Lack of added riboflavin had the most effect on hatchability, with 0% being recorded for both strains after 13 wk of treatment. All other treatments depressed hatchability for RIR (P < 0.05), although the pattern was not as well defined with W.L. Both breeds responded to re introduction of vitamins, such that at the end of the trial no significant (P > 0.05) differences in production or hatchability were recorded. There was no difference in growth rate of chicks hatched from eggs produced during the 8th wk of treatment.

Demography and viability analyses of a diamondback terrapin population

2003 ◽  
Vol 81 (4) ◽  
pp. 716-726 ◽  
Author(s):  
Matthew G Mitro
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Rhode Island ◽  
Population Model ◽  
Population Growth Rate ◽  
Diamondback Terrapin ◽  
Matrix Population Model ◽  
Demographic Stochasticity ◽  
Mark Recapture ◽  
Declining Populations

The diamondback terrapin, Malaclemys terrapin, is a long-lived species with special management requirements but quantitative analyses to support management are lacking. I analyzed mark–recapture data and constructed an age-classified matrix population model to determine the status and viability of the only known diamondback terrapin population in Rhode Island. Female diamondback terrapins were captured, marked, and recaptured while nesting during 1990–2001. Population growth rate (λ) was 1.034 (95% confidence interval = 1.012–1.056). For the preceding 5 years, however, abundance had been stable at about 188 breeding females. Adult apparent survival was high but declined slightly by 0.14% per year from 0.959 in 1990 to 0.944 in 2000. Recruitment of breeding females also decreased during the study period; therefore, survival was increasingly a greater component of population growth rate. Juvenile survival was 0.565 at λ = 1.034 and 0.446 at λ = 1. Both retrospective (mark–recapture) and prospective (matrix population model) analyses showed a greater influence of survival versus reproduction on population growth. Population- model projections showed that capping nests to improve reproductive success could increase population growth rate, but the magnitude of increase was positively related to pre-reproductive survival, therefore negating nest capping as a remedy for declining populations or poor survival. Extinction attributable to demographic stochasticity is unlikely.

The influence of aureomycin on chick-rearing results using East African feedingstuffs with special reference to importance of experimental design for accurate statistical analysis

1960 ◽  
Vol 55 (2) ◽  
pp. 269-272 ◽  
Author(s):  
J. C. M. Trail ◽  
D. J. L. Casley
Keyword(s):  
Growth Rate ◽  
Statistical Analysis ◽  
Experimental Design ◽  
Mortality Rate ◽  
Rhode Island ◽  
Feed Conversion ◽  
East African ◽  
High Level ◽  
Feed Conversion Rate ◽  
Careful Design

Groups of Rhode Island Red chicks were fed a mash made up from East African feedingstuffs or that diet supplemented with a high level rate of aureomycin—97 g. aureomycin hydrochloride per ton of feedingstuff. The chicks were kept on wire for 8 weeks. The initial improved growth rate of the chicks fed the aureomycin supplemented feedingstuff was not maintained, nor was there any statistical indication that the addition of aureomycin improved the feed conversion rate.Although the mortality rate appeared to be very much lower in the chicks fed the aureomycin supplement, the evidence was too limited to allow this to be attributed solely to the effects of the aureomycin.The experiment illustrates the need for careful design in order that the effect of the factors to be tested may be separated from the effects of other factors contained in the experiment and not confounded with them. Moreover, advanced statistical analysis should be used as an invaluable aid to, but not a substitute for, visual or graphical examination of results, for such examination often yields valuable indications of possible lines of analysis and may avoid the drawing of unjustified conclusions.

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