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The aim of this study was to compare the growth pattern of seven strains of Japanese quail including Wild, Italian Speckled, Tuxedo, Scarlett, English white, White button, and A&M Texas by nonlinear growth functions including Gompertz, Richards, logistic, Lopez, and Weibull functions. The body weights of the unselected randomly bred populations of these strains were measured weekly from 1 to 42 days of age and then used to fit functions. The fitness of each function was assessed by statistics including the mean square error, Akaike information criterion, Bayesian information criterion, and adjusted coefficient of determination. The results showed that Gompertz was the best function for describing the growth curve in Italian Speckled and Wild strains; however, the best function for the other strains was the logistic function. The maximum and minimum values for age and weight at the inflection point were obtained for the White button and Scarlett strains, respectively. The weight to age ratio at the inflection point was maximized for Italian Speckled. The best growth rate was observed for the Italian Speckled strain, whereas the White button strain exhibited the worst growth rate. In conclusion, the Italian Speckled strain had the best properties among the tested strains for breeding as broiler poultry. [ABSTRACT FROM AUTHOR]

The main goal of breeding programmes is to maximise the genetic improvement of the economic traits of farm animals. Beside the economic traits, the birds' survival has directly influenced on the economic gain. Therefore, this study aimed to investigate the genetic relationship between survival and productive traits in Japanese quail. A total of 1854 records were collected during four generations from 2017 to 2019 in Khorasan Razavi Agricultural Research and Training Centre (KRARTC). Data were used to estimate the genetic correlations among quail survival (S) with egg weight (EW) and body weight gain (BWG) traits. Linear-threshold model was used to estimate (co)variance components, and genetic parameters of traits via the Gibbs sampling method. The heritability of EW was 0.04, and the heritability estimates for survival at different ages ranged from 0.138 to 0.399 in joint analysis with EW. The highest negative genetic correlation between EW and S0–14 (i.e. survival up to 14 d) was obtained as −0.704. The highest and lowest heritability of weight gain traits for BWG0–7 and BWG7–14 were 0.583 and 0.116, respectively. The analyses of BWG traits with survival at different ages revealed that the genetic correlations ranged from 0.015 (between BWG0–7 and S0–14) to 0.638 (between BWG0–7 and S0–7). This study showed that the genetic selection for survival at different ages could be effective. On the other hand, selection for BWG0–7 could also indirectly improve the survival in quails because of the positive and high genetic correlation between BWG0–7 with S0–7. Genetic improvement of production traits in quail may lead to reduced survival in quail. Studies regarding on the survival of quail were yet not carried out. Heritability of the survival at different ages showed that genetic selection for this trait could improve the survival. Survival at different ages had a negative genetic correlation with egg weight (EW), and body weight gain (BWG) traits after 21 d of old. [ABSTRACT FROM AUTHOR]

• Dominance and epistasis effects are important for the average daily gain traits and could be added to evaluation models. • Adding the non-additive genetic effects to models led to increase the accuracy of estimated breeding values. • The adgbww3 and adgbww6 traits can be the basis of selection for the next generation. Considering the dominance and epistasis effects in the analysis can increase the accuracy of estimating breeding values. The objective of this study was to fit the best model for each average daily gain trait (average daily gain from birth to weaning (adgbwww., from birth to 3 months (adgbww3), from birth to 6 months (adgbww6), from weaning to 3 months (adgwww.), from 3 to 6 months (adgw3w6), from 6 to 9 months (adgw6w9), and from 9 to 12 months (adgw9w12)) and the estimation of the genetic parameters and variance components, especially non-additive genetic effects, in Adani goats. Analyses were carried out using the Bayesian method via the Gibbs sampler animal model by fitting 18 different models. With the best model, direct heritability estimates were 0.093, 0.250, 0.256, 0.084, 0.036, 0.048, and 0.151 for adgbwww. adgbww3, adgbww6, adgwww., adgw3w6, adgw6w9 and adgw9w12 traits, respectively. Maternal genetic and maternal permanent environmental effects were significant only for adgbwww.trait. Dominance and epistasis effects were significant almost for all traits and as a proportion of phenotypic variance was the range from 0.068 to 0.221 and 0.106 to 0.237, respectively. Adding dominance and epistasis effects to models reduced the error variance and the accuracy of estimating breeding values was increased. The accuracy of breeding values of these traits with the best models ranged from 0.456 to 0.674, 0.493 to 0.656, and 0.424 to 0.674 for all animals, 10 % of best males and 50 % of the best females, respectively. The result of the present study suggests that dominance and epistasis effect was important for average daily gain traits of Adani goats and should be included in evaluation models. [ABSTRACT FROM AUTHOR]

• In the present study, survival analysis was performed using of time-dependent variable and censored data via gibbs sampling method. • The non-genetic effects had a significant effect on lamb survival from birth to the last recording date. • Estimated direct heritability for survival ranged 0.097 to 0.157. The contribution of maternal permanent environmental variance ratio was estimated higher than maternal heritability. • Improvement of survival for Sangsari breed could be possible through management practice as well as genetic selection. The aim of this study was to investigate the genetic and non-genetic effects on survival traits of Sangsari sheep from birth to the last recording date. Data base with 35,470 sheep survival records was collected during 1988 to 2010 in 11 flocks by the Animal Breeding Center of Iran. The non-genetic effects were evaluated on hazard rate of sheep in different times with survival and cmprsk packages. Exponential distribution based on censored data was used to estimate the genetic parameters of the survival from birth to the last recording date. The linear animal models were fitted using Bayesian method via Gibbs sampling of the MCMCglmm package. The overall mortality rate for Sangsari lambs was 2.00 and 25.72% for birth to 100 and 500 day of age, respectively, and its value increased upto 90.54% till 3400 day of age. The results indicated that the year and month of birth, sex of lamb, birth weight, age of ewe, flock (P < 0.001), and type of birth (P < 0.01) had a significant effect on sheep survival. Estimated direct heritability for survival from birth to the last recording date by different linear models ranged 0.097 to 0.157. The contribution of maternal permanent environmental variance ratio was estimated higher than maternal heritability, thus this effect must be considered in the evaluation models for improving sheep survival. The present findings suggest that sheep survival improvement could be possible through management practice as well as genetic selection. [ABSTRACT FROM AUTHOR]

Highlights • Humoral immune responses in Japanese quail are heritable. • After immunization of the birds with SRBC, genetic correlations between immunoglobulin M (IgM) and early growth traits are positive, but for AbT and IgY are negative. • Genetic correlations for AbNDV with BW traits are negative, but with BWG traits are positive. • Genetic selection for IgM responses could improve growth traits. Abstract The aim of this study was to estimate genetic parameters of early growth performances and humoral immune responses (antibody titers against sheep red blood cells (SRBC) and Newcastle Disease Virus (NDV)) in Japanese quail. For this purpose, a total of 10,923 records of early growth traits including body weights (BW) at 0, 5, 10, 15 and 20 d old and body weight gain (BWG) between 0–5, 5–10, 10–15 and 15–20 days, and 2,314 records of humoral immune responses were used to estimate genetic parameters through multiple-trait Bayesian analyses. The estimates of heritability of BW and BWG traits were 0.14 to 0.28 and 0.08 to 0.10, respectively. The range of genetic and phenotypic correlations for BW traits varied from 0.63 to 0.98 and 0.17 to 0.89, respectively. Furthermore, estimates of genetic and phenotypic correlations for BWG traits at different ages were in the range of 0.46 to 0.86 and 0.12 to 0.46, respectively. Heritability estimates of total antibody titer (AbT), titer of immunoglobulin Y (IgY) and titer of immunoglobulin M (IgM) against SRBC were 0.21, 0.24 and 0.20, respectively, but h2 of antibody titer against NDV (AbNDV) was lower than those of estimated for SRBC antigen (h2 = 0.17). Genetic correlations between antibody titers against SRBC and NDV were similar (0.42 − 0.46). Genetic correlations were positive only for IgM with BW traits, however, estimates of genetic correlation between BW traits at different ages with AbT and IgY were negative and moderate (−0.30 to −0.66), and with AbNDV were negative and low (−0.13 to −0.25). Like BW traits, genetic and phenotypic correlations between AbT and IgY titers and BWG traits were negative and varied from −0.21 to −0.72, while genetic correlations of BWG traits with IgM and AbNDV titers were both positive (0.11 to 0.27 and 0.23 to 0.31, respectively). It is suggests that selection to improved BW and BWG traits may lead to decline of humoral immune responses in Japanese quail. However, improvement of BW and BWG traits and humoral immune responses would be possible through selection for IgM titers against SRBC due to its high and positive genetic correlation with growth traits. [ABSTRACT FROM AUTHOR]

Early growth traits in quails are considered as the growth performances before the inflection point which are genetically different from body weights (BW) at later stages. Moreover, in addition to growth performance, humoral immunity is moderately heritable and is considered in some breeding programs. However, estimating the direct genetic, particularly the maternal genetic correlations between growth and immunity in quail, are not studied sufficiently, which were the aims of the present study. The quails' BW were recorded at hatch (BW0) to 25 d of age with a 5-d interval and body weight gains (BWG) were measured as average growth performance of the birds in a 5-d period. Antibody titer against Newcastle disease virus (IgN) was measured through the hemagglutination inhibition (HI) test. For titration of anti-SRBC antibodies (IgY and IgM), a hemagglutination microtiter assay was used. In general, growth records in 4,181 birds and humoral immune responses in 1,023 birds were assigned to the study. The genetic parameters were estimated by single-trait analysis via Gibb's sampling. After finding the best model for each trait, multi-trait analysis was done to estimate the direct and maternal genetic correlations. Direct heritabilities (h2) were estimated to be moderate for BW (0.481−0.551) and BWG (0.524−0.557), while h2 for immune responses were low (0.035−0.079). Maternal environmental effect (c2) was only significant for BW0, BW5, and BWG0-5. Maternal heritabilities (m2) for BW and BWG were all lower than corresponding h2, ranging from 0.072 (BW25) to 0.098 (BW0). The m2 for IgN (0.098) was more than 2.5 times greater than h2 (0.040) for this trait. Direct (r a) and maternal (r m) genetic correlations between IgN-BW, IgY-BW, and IgY-BWG were negative, while ra and rm for IgM-BW, IgN-BWG, and IgM-BWG were positive. The r a between humoral immune responses were low to moderate and rm was significant only for IgY-IgM (0.339). Given positive genetic correlations in BWG-IgN and BWG-IgM as well as positive genetic correlations between both IgN and IgM with IgY, it is suggested that including the BWG in the breeding programs would directly result in the improvement of the birds' growth performance. It would also contribute indirectly to the improvement of the birds' humoral immune responses. [ABSTRACT FROM AUTHOR]

In most countries, ostrich farming is considered a developing branch of the efficient poultry industry. The profitability of ostrich farm requires specific consideration of productions features such as the female fertility, egg production, hatchability, and growth performance. Hence, this study aimed to fit nonlinear functions to describe the ostrich egg production pattern to achieve the most appropriate and recommendable mathematical function for future studies. For this purpose, 14,507 daily records of 184 female ostriches in 5 production seasons (periods) during 2016 to 2021 were used. Five nonlinear functions including Incomplete gamma (Wood function), Corrected gamma (McNally), nonlinear Logistic (Yang), Logistic (Nelder), and Lokhorst were fitted for modeling the egg production curve in ostrich. The goodness of fit criteria's including Mean Square Error (MSE), Likelihood Ratio Test (LRT), Akaike Information Criterion (AIC), and Bayesian Information Criterion (BIC) were used to evaluate and selection of the best function. The results indicated that the Wood and the McNally functions with a slight difference in all fitting criteria were the best-fitted functions and the Yang function with the highest values of MSE, LRT, AIC, BIC, were the most inappropriate function to describe the ostrich egg production curve. The McNally and the Wood can be recommended as appropriate functions to describe egg production during 5 production seasons in the studied ostrich flock. [ABSTRACT FROM AUTHOR]

To have a better contribution to the poultry production community, the Poultry Science Association founded journals including Poultry Science (PS) at 1921. Now, after 100 yr of publishing, PS ranks between the top 10 journals in the category of "agriculture, dairy, and animal science". One hundred years after publishing the first paper in PS, the poultry industry has been completely revolutionized. Hence, it will be interesting to establish scientometrics study of the PS development during the last century. Therefore, based on findings of the current study, among countries/authors' collaborations, future research fronts, and possibility of hot topics in the coming years may be predictable. Accordingly, a total of 22,451 articles were retrieved. For content analyses, according to the PS categorization for subject areas, 14 different subject areas were developed, including "behavior, breeding and quantitative genetics, education and extension, health and welfare, immunology, management and environment, metabolism and nutrition, microbiology and virology, modeling, molecular biology, physiology and anatomy, production, products, processing and marketing, and reproduction". Considering the 100-yr of PS, the most frequent subject area was "nutrition and metabolism" (14,109 articles), and "modeling" (1,114 articles) attracted less scholarly attention. However, considering the last decade (2011–2020), the most important subject area was "molecular biology" (1,420 of 2,466 articles; 57.58%), followed by "modeling" (544 of 1,144 articles; 48.88%). Moreover, the most frequent poultry species/strains were broilers (retrieved in 6,156 articles), followed by laying hens, turkeys, and quail. Considering collaboration of countries and researchers, it can be said that a total number of 108 countries contributed to PS, with the most prolific country being United States (with 9,421 articles; 43.16%), followed by China, Canada, the Netherlands, and Japan. Among the authors, Harms RH (287 articles), and Siegel PB (208) were the most prolific authors, and Siegel PB and Dunnington EA (71 articles) had more collaborations. To study keyword trends, including 3 time periods broilers was the central co-occurrent keyword, while the importance of chickens and turkeys declined during the time. Salmonella spp. was a constant representative of poultry microbiology during 100 yr. While "nutrition and metabolism" was the most important subject area, nutrition-related keywords (major items) were not concentrated and co-occurred with a variety of keywords from different subject areas. While "molecular biology" ranked first over the past decade, the importance of "nutrition and metabolism" should not be ignored. In fact, in recent years, molecular basis of the nutrition has been studied. In big-data era and due to developing the molecular biology technologies, it seems that using mathematical modeling and computational methodologies will increase and probably remains as one of the most attractive research areas for scientists at least in the upcoming future decades. [ABSTRACT FROM AUTHOR]