Enterococcus hirae-Associated Endocarditis Outbreak in Young Broiler Breeders of the Female Line.

1. Female chicks from 6 pure lines of broiler breeders were obtained from international broiler breeder companies. The lines were from three female and two male lines and a relaxed selection line derived from one of the male lines (M2) and maintained without selection for 25 years (generations). Replicate groups from each line were reared in floor pens and fed ad libitum. An additional group of the M2 male line was feed restricted and housed in similar pens. Twenty birds from each group were photostimulated after housing them in individual cages at 14 weeks of age. Ovarian follicular dynamics and follicular sensitivity were determined after the onset of lay. 2. Female lines had a greater proportion of atretic follicles and more groups of multiple follicles than male lines. Body weights, fatness and age at puberty were similar in male and female lines. 3. The relaxed selection line had more abdominal fat than any of the selected lines and the ovary contained a similar number of normal yellow follicles as the selected male line. 4. Feed restriction decreased body weight, the numbers of yellow follicles, multiple yellow follicles and the proportion of atretic yellow follicles, and increased the age at onset of lay. 5. The response of ovarian follicles of three different sizes to exogenous gonadotrophin stimulation with PMSG was similar in small yellow follicles, 5 to 6 and 2 to 3 mm white follicles in a female line, a male line and its relaxed line fed ad libitum. 6. The results suggest that the original lines from which modern male-line broiler stocks are derived had a relatively large number of yellow follicles and a high propensity for multiple ovulation at the onset of lay. Separate selection for different traits in male and female lines has not had a dramatic effect on ovarian function or sensitivity to gonadotrophin stimulation.

ISHS XXVI International Horticultural Congress: Issues and Advances in Postharvest Horticulture AROMA VOLATILE DIFFERENCES IN COMMERCIAL ORANGE-FLESHED CANTALOUPES, THE INBRED PARENTAL LINES AND STORED FRESH-CUTS

Age Effect of Male and Female Broiler Breeders on Sperm Penetration of the Perivitelline Layer Overlying the Germinal Disc

Hybrid crops, an important part of modern agriculture, rely on the development of male and female heterotic gene pools. In sunflowers, heterotic gene pools were developed through the use of crop‐wild relatives to produce cytoplasmic male sterile female and branching, fertility restoring male lines. Here, we use genomic data from a diversity panel of male, female, and open‐pollinated lines to explore the genetic changes brought during modern improvement. We find the male lines have diverged most from their open‐pollinated progenitors and that genetic differentiation is concentrated in chromosomes, 8, 10 and 13, due to introgressions from wild relatives. Ancestral variation from open‐pollinated varieties almost universally evolved in parallel for both male and female lines suggesting little or no selection for heterotic overdominance. Furthermore, we show that gene content differs between the male and female lines and that differentiation in gene content is concentrated in high FST regions. This means that the introgressions that brought branching and fertility restoration to the male lines, brought with them different gene content from the ancestral haplotypes, including the removal of some genes. Although we find no evidence that gene complementation genomewide is responsible for heterosis between male and female lines, several of the genes that are largely absent in either the male or female lines are associated with pathogen defense, suggesting complementation may be functionally relevant for crop breeders.

Records obtained from 4336 pullets progeny for strain A and 4843 pullets, progeny for strain B under selection for part-period egg production to 280 days of age were used for this study. The response variables measured were Age at sexual maturity (ASM), Egg number to 280 days (EGG280 D), Egg weight average (EWTAV) and Body weight at 40 weeks of age (BWT40). The genotypic response was only 0.42 eggs per generation in the male line. The female line population showed a much higher positive response to selection, the phenotypic value being 1.67 eggs per generation while the genotypic response was 3.1 eggs per generation. The genetic correlation estimates between the different economic traits ranged from -0.70± 0.38 to 0.82 ± 0.42 vs -0.71 ± 0.47 to 0.76 ± 0.29 for the male and female lines respectively. The correlation between egg number and egg weight was small non significant. ASM was highly and negatively correlated with egg production to 280 days in both lines being higher than- 0.60 in most cases. The genetic correlation between egg number and BWT40 showed no definite trend. In the female line, correlated response in age ASM and BWT40 had negative values. In the male line however except for BWT40 which showed a positive correlated response of 3.4g/year, all other traits showed negative correlated responses. Generally it wa s evident that selection was more effective in improving the egg number in the female line than in the male line showing an increase of 1.67 vs 0.19 eggs per year in the female and male lines, respectively. The low egg number reported was as a result of the delay in sexual maturity especially during the later years of th e selection experiment. Another factor that may have contributed to the variable response achieved from generation to generation may also be due to varying season of hatching across generation. However the positive response in the female line population may be attributed to reduced age at sexual maturity.

Growth models are important for optimization of feed formulation and breeding programs in turkeys. The objectives of this study were 1) to compare sex and line differences in turkeys in parameter estimates of mono- and di-phasic Gompertz growth models, and 2) to evaluate mono and diphasic mixed Gompertz growth models to determine the variation in parameter estimates in a group of female line turkey toms. A total of 1,056 manually recorded weekly average body weight (BW) observations from male and female turkeys of a male and female line from weeks 1 to 20 were used for objective 1. Daily median values of automatically collected individual BW of female line turkey toms were used for objective 2 and random components associated with individual subject animals related to mature weight and/or timing of maximum gain during each phase were introduced in the Gompertz model. Growth curve shapes were different between male line toms, male line hens, female line toms, and female line hens (P < 0.001). However, inflection points were similar between male and female line toms and between male and female line hens (14.06 vs. 13.72 wk and 11.22 and 10.71 wk, respectively), while mature BW differed between lines by 6.49 and 3.81 kg for toms and hens, respectively. The normalized growth rate constant (growth rate constant corrected for mature weight) was around the same magnitude between male and female line toms (0.0031 vs. 0.0038, respectively), but slightly lower in male line hens compared to female line hens (0.0072 vs. 0.0091, respectively). Diphasic Gompertz models described growth better in all line × sex combinations compared to the monophasic models (P < 0.001) and mixed diphasic Gompertz models showed improved fit over mixed monophasic Gompertz models. The correlation structure of the random components identified that individuals with a higher mature weight had a later inflection point and lower growth rate coefficients. These results provide tools for improved breeding practices and a structure to evaluate the effects of dietary or environmental factors on growth trajectories.

Evaluation of the duration of sperm fertilizing ability in five lines of commercial broiler breeder and Delaware cross males

The objective of this study was to estimate genetic and phenotypic correlations amongst traits in layer type chickens under reciprocal recurrent selection. Matings within pure male line and female lines were carried out to produce purebred male line (AA x AA) and female line (BB x BB). A total of 364 pullets arising from 207 hens and 23 cocks in generation 1 and 440 pullets from 70 hens and 10 cocks in generation 2 under selection were monitored in individual cage units for part period egg production up to 280 days. Parameters considered were age at sexual maturity (ASM), body weight at 20 and 40 weeks (BW 20 and BW40), egg weight average (EWTAV) and egg production up to 280 days (Egg 280). Results obtained shows that ASM had a high negative genetic (-0.52 to -0.64) and moderate phenotypic (-0.39 to -0,46) correlations with BW20 in the male line, positive genetic and phenotypic correlations with EWTAV in both male (0.41 to 0.80 and 0.07 to 0.26) and female line (0.53 and 0.09 to 0.14) and negative genetic and phenotypic correlations in both male (0.45 to -0.65 and -0.08 to -0.53) and female (-0.37 and -0.20), lines, respectively. Similarly, BW40 had positive genetic and phenotypic correlations (0.68 to 0.93 and 0.01 to 0.20) with Egg-280 in the female line. EWTAV had a negative genetic and phenotypic correlation with Egg280 in both male (-0.53 to -0.96 and -0.09 to -0.17) and female line (-0.15 to -0.27 and -0.09 to -0.15), respectively. It was concluded that the favourable correlations that exist between traits measured in this study for both male and female lines indicate the presence of non-additive genetic effects which can be utilized through selection and crossing for commercial use.

This study examines the effect of grandparent, parent, and hybrid brown chickens, selected from 3 generations of pure lines, on hybrid egg-laying performance. The study was conducted at the Poultry Research Station of Ankara. In the first stage, 4 grandparent lines were derived from 2 pure line base populations. Grandparent lines included 2 male lines (low body weight and high egg weight) and 2 female lines (low body weight and high egg production). In the second stage, grandparent male and female lines were reciprocally crossed to produce 4 parent lines. In the third stage, male and female parental lines were crossed to produce 4 hybrid lines. The average age at first egg of grandparents, parents, and hybrids was 147.68, 154.46, and 157.53 days, respectively; body weight was 1662.95, 1699.19, and 1684.24 g, respectively; average number of eggs was 128.10 (43 weeks), 241.84 (64 weeks), and 303.89 (72 weeks), respectively; and egg weight was 57.46 (43 weeks), 58.28 (64 weeks), and 68.89 g (72 weeks), respectively. As a result, this study produced 4 parent lines with good combining ability for hybrids.

1. Field data on the reproductive performance of parent stock and grandparent female line and male line broiler breeders were extracted from a commercial database covering the years of hatch from 1989 to 2002. The data were from the UK, Western Europe, Central and South America and Japan. Quadratic regression curves were fitted to the data to estimate the long-term phenotypic trends in total egg production, hatching egg production, chick numbers, hatchability and female mortality. 2. Changes in performance over time were similar in the UK, Western Europe and Central and South America and are consistent with the suggestion that genetic selection in separate breeding programmes in the UK (supplying the UK and Western Europe) and Brazil (serving Central and South America) was associated with similar improvements in the performance of commercial parent stock and grandparent flocks. Changes in performance in Japan (supplied from the UK) were different but recent performance was similar to those in the other regions. 3. The mean annual improvements over 10 years to 2002 for male line, female line and parent stock, respectively, were 0·4, 1·7 and 1·7 for total egg number; 0·5, 1·8 and 1·6 for hatching egg number; 0·6, 1·8 and 1·3 for total chick production; 0·25, 0·47 and 0·09% for hatchability; and −0·69, −0·05 and −0·41% for female mortality. 4. The results are consistent with claims that significant genetic change in pedigree selection (nucleus) flocks by the primary breeding company are reflected in substantial improvements in reproductive performance in commercial flocks. The presence of similar rates of improvement in different geographical regions as a result of genetic selection in two continents representing tropical and temperate regions suggests that genotype–environment interactions for reproduction traits are not important.

Genotype x environment (GxE) interactions can reduce the accuracy of a model to predict the performance of an animal and have an undesirable influence if not accounted for when estimating breeding values. Consequently, identification of these GxE is necessary when considering a turkey breeding program. Reranking based on the genetic prediction of turkey egg production, fertility, and hatchability in different seasons was indicative of a potential GxE interaction. Quantification of the GxE interactions was based on the genetic correlation estimated when traits were expressed in different seasons. Egg production was expressed as the percentage of days with an egg produced; fertility represented the proportion of hatched eggs that contained a fertile embryo; and hatchability was defined as the percentage of fertile eggs that produced a live bird. Variance components and heritability for egg production, fertility, and hatchability were estimated using ASReml. The heritability (h(2)) of egg production was calculated to be 0.32 for both lines with the phenotypic and genetic variance, 141.3 and 45.58 (percent days with egg produced)(2) and 118.3 and 38.35 (percent days with egg produced)(2) for female and male lines, respectively. The h(2) estimates for fertility were 0.08 in both lines with and of 293.3%(2) and 24.03%(2), and 576.9%(2) and 48.43%(2) for female and male lines, respectively. The hatchability h(2), and estimates were 0.09, 267.1%(2), and 24.44%(2), respectively, for the female line and 0.15, 582.2%(2), and 90.01%(2) for the male line, respectively. Based on an animal model, the variance components were used to calculate estimated breeding values for each trait. The annual fluctuation in estimated breeding values resulted in the need to evaluate egg number, fertility, and hatchability as 2 traits, summer and winter lay. The correlation between the 2 traits was less than unity (female line: r(egg production) = 0.76, r(fertility) = -0.20, r(hatchability) = 0.75 and male line: r(egg production) = 0.86, r(fertility) = 0.19, r(hatchability) = 0.68) suggesting a GxE interaction, and animals will significantly rerank in genetic predictions for these reproductive phenotypes in different seasons of lay. Egg production, fertility, and hatchability in turkeys could be considered as 2 distinct traits in an animal model based on season of lay.

Genetic relations between natural antibodies binding keyhole limpet hemocyanin and production traits in a purebred layer chicken line

The present study investigated and identified genetic diversity between native White chicken lines and two commercial Broiler (Rose) and Layer (Isa Brown) chicken breeds using RAPD markers and a sequencing technique. All primers applied produced 151 scorable bands with percentage polymorphic loci of 54.93 % within chicken populations, as per the results of the RAPD marker. The maximum amplified fragment by primer OPC-11 was 22 and the fewest by primer OPAA-03 was 7. For all loci analyzed, the effective number of alleles (ne), means the observed number of alleles (na), Shannon's information index (I), and gene diversity (h) was 1.4394, 1.5493, 0.3496, and 0.2441, respectively. The presence of a high number of polymorphisms and targeted (71) loci across all chicken populations indicates that RAPD-PCR techniques provide sufficient genetic distance and higher genetic variation among chicken populations. The highest identity of the blasted sequences of the 18srRNA gene of local white chicken is 90.41 % and 84.23 %. Likewise, a total of 46 and 27 nucleotides are altered with 27 and 10 gaps in both sequences for the first and second regions, respectively. According to both phylogenetic trees, the local white chicken had a stronger sense of individuality and was slightly closer to the commercial broiler breeds than the layer chicken breeds. As a result, it suggests that enhancing the local chicken line requires a broiler breeding program, as well as cross-breeding with other native chicken lines to obtain hereditarily significant new strains.

Energy metabolism and some performance parameters were investigated in laying hens of 3 different body weight‐genotypes: 6×7 (normal‐sized, crossbred from normal‐sized male and female lines, group 1), 47 x 38 (dwarf‐sized, breeding from a dwarf‐sized male line and a normal‐sized female line, group 2) and 44×47 (dwarf‐sized, breeding from dwarf‐sized male and female lines, group 3). Energy balance was measured by indirect calorimetry through C‐and N‐balances in 12 animals of each group during 10 consecutive days at production peak, within the period between the 27th and the 37th week of age. Hens were caged individually at 23°C environmental temperature and fed ad libitum on a laying mash. The mean body weight in the dwarf‐sized groups 2 and 3 was 32% lower than in the normal‐sized group 1 during the energy balance period. The daily gross energy intake in group 2 and 3 was decreased by 33 and 34%, respectively. There were no significant differences in digestibility and metabolizability of gross energy between the groups. The energy requirements for maintenance [kJ ME/kg 0.75 d] derived from the energy balances were lower by 4% (P>0.05) and 14% (P<0.05) in the dwarf‐sized groups 2 and 3 as compared with the normal‐sized group 1, when equal coefficients of partial efficiency of metabolizable energy utilization for energy retention in body and eggs are assumed for the 3 body‐mass genotypes. There were no relevant differences in body composition at the end of the energy balance periods as well as in egg composition between the 3 experimental groups.

Two hundred day-old chicks of Lohmann Brown Broiler male (MPL) and female (FPL) parent lines were evaluated for production efficiency under the humid tropical environment. Chicks were reared on deep litter and fed chick breeder mash (0-8 weeks), grower mash (9-16 weeks), and broiler breeder mash (17-49 weeks). Water was supplied ad libitum. At point of lay, birds were floor-mated according to line in a ratio of 1 cock; 6 hens. Average body weights at 20 weeks were 2623.99 and 2189.35g for MPL and FPL, respectively. Female parent line chicken came into lay 4 days earlier than their MPL counterparts (142 vs 146 days). No statistical difference was observed in the total feed consumption per bird, with the values 8.89kg (MPL) and 8.62kg (FPL). There were no significant (P&gt;0.05) differences between the two lines in percent hien-day egg production (PHD), fertility and hatchability of fertile eggs, values of which were respectively, 49, 12, 79.32 and 81.01 for the male line and 62.11, 80.89 and 82.28 for the female line during the last 26-49 weeks of age.