Influence of selection for egg production on egg quality traits in Japanese quail

The current study investigated the influence of selection for increased egg production on external and internal egg quality traits over five generations in Japanese quail. A total of 4325 fresh eggs from 1326 females were collected each week during the egg-laying period to estimate heritability, genetic and phenotypic correlations, and correlated response of external and internal egg quality traits to selection for egg number (EN). The direct response to selection indicated an increase of 7.7 ± 0.27 eggs produced during the 90 days following production of the first egg. The correlated responses to selection indicated that selection for higher EN can be expected to increase EW and increase egg quality. Estimates of heritability ranged from 0. 11 to 0.35 for external egg quality traits and from 0.08 to 0.32 for internal egg quality traits. Estimates of the genetic correlations of EN with external and internal traits were positive, ranging from 0.09 to 0.25 and from 0.02 to 0.27, respectively. These estimates indicated few if any genetic antagonisms that would adversely affect selection response. However, eggshell thickness would not be expected to change as a result of selection for EN. Thus, the external and internal quality of Japanese quail eggs could be improved by selection for high egg production

Some factors affecting production and milk composition characters in a crossbreeding experiment involving Gabali and V- line rabbits in Egypt

[EN] Data from 662 litters and 221 samples (two replicates per each sample) of rabbit milk were collectedfrom three different genetic groups [Gabali (G), V-line (V) and GxV (F1)] to study the effect of line and of somenon-genetic factors affecting production and milk composition traits. The studied traits were: number bornalive (LSBA); litter size at weaning (LSW); litter weight born alive (LWBA); litter weight at weaning (LWW); totalmilk yield (TMY) and protein, fat, total solids (TS), ash, phosphorus (P), potassium (K), sodium (Na), calcium(Ca) and magnesium (Mg) milk content. The genetic group effect was significant for LSBA [V (7.3) and F1(7.3)were superior to G (6.6)); LWBA (higher values for V (416 g) and F1 (405 g) than for G (382 g)]; TMY [G (3497g) and F1(3486 g) higher than V (3042 g)]; milk fat [F1 (26%) and G (25%) superior to V (23%)] and milkTS[F1(42%) superior to G (40%) and V (39%)]. The estimates of the heterosis effect ranged between 1.6% and12.8% for production and milk gross chemical traits, being significant only for milk fat content (9.1%). Thepositive values of the heterosis estimates for those traits and the complementarity between the G breed andthe V line, the G superior in milk related traits but the V superior in prolificacy, show the interest of their crossand of the synthetic lines derived from them. The heterosis was non-significant for milk mineral content traits.The parity effects were significant for LSBA, fat, TS, ash and K (the maxima were reached at 6th or 5th parity).The effect of week of lactation was significant for fat, ash and TS, corresponding the maximum values of fatand TS to the 3rd and 4th week. The year-season or the year-month effects were significant for all traitsshowing the importance of including these time-period factors into the statistical models proposed for thetraits.This project was supported by the Spanish Agency of International Cooperation (A.E.C.I.) and the Center of Cooperation for Development of the Universidad Politécnica de Valencia, Spain. We, also, appreciate the effort of Prof. Dr. Maher Khalil supporting the project.Iraqi, M.; Shenana, M.; Baselga, M. (2007). Some factors affecting production and milk composition characters in a crossbreeding experiment involving Gabali and V- line rabbits in Egypt. World Rabbit Science. 15(3). doi:10.4995/wrs.2007.594SWORD15

Polymorphic characterisation of gallinacin candidate genes and their molecular associations with growth and immunity traits in chickens

1.Four gallinacin (GAL) genes were assessed by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) to characterise these genes in Fayoumi (F) and Rhode Island Red (R) breeds and their crosses of Rhode Island Red × Fayoumi (½R½F) and Fayoumi × Rhode Island Red (½F½R). 2.Genes examined were GAL2, GAL3, GAL4 and GAL5. The molecular associations between the SNPs of the gallinacin genes and body weight, caecal bacterial count and the serum antibody titres of IgA, IgG and IgM were determined. In the R breed, the frequency of TC genotype was higher than TT and CC genotypes for the GAL3 gene. The GG genotype frequency was higher than AA and AG genotypes for the GAL4 gene in the other genetic groups, and the CA genotype frequency was higher than CC and AA genotypes in crosses for the GAL5 gene. 3.In all populations, the frequency of the C allele was higher than the T allele for the GAL3 gene, the G allele was higher than the A allele for the GAL4 gene and the C allele was higher than the A allele for the GAL5 gene. The observed heterozygosity in R, ½R½F and ½F½R was 0.476, 0.375 and 0.158 for the GAL3 gene, 0.458, 0.615 and 0.250 for the GAL4 gene and 0.053, 0.792 and 0.739 for the GAL5 gene, while the expected heterozygosities were 0.490, 0.430 and 0.145 for the GAL3 gene, 0.430, 0.348 and 0.219 for the GAL4 gene and 0.229, 0.478 and 0.496 for the GAL5 gene, respectively. 4.On a molecular level, the genotype TT was significantly higher for body weight than TC and CC genotypes in the GAL3 gene. Birds with the GG genotype had a significantly lower Salmonella typhimurium count than birds with AA genotype in the GAL4 gene. Birds with the genotype AA had higher significant body weights than those with CC and CA genotypes in the GAL5 gene. 5.The results indicated that the GAL3, GAL4 and GAL5 genes are potential candidates for selection programmes to improve S. typhimurium resistance and body weight in chickens

Mapping liver fat female-dependent quantitative trait loci in collaborative cross mice

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the western world, with spectrum from simple steatosis to non-alcoholic steatohepatitis, which can progress to cirrhosis. NAFLD developments are known to be affected by host genetic background. Herein we emphasize the power of collaborative cross (CC) mouse for dissecting this complex trait and revealing quantitative trait loci (QTL) controlling hepatic fat accumulation in mice. 168 female and 338 male mice from 24 and 37 CC lines, respectively, of 18-20 weeks old, maintained on standard rodent diet, since weaning. Hepatic fat content was assessed, using dual DEXA scan in the liver. Using the available high-density genotype markers of the CC line, QTL mapping associated with percentage liver fat accumulation was performed. Our results revealed significant fatty liver accumulation QTL that were specifically, mapped in females. Two significant QTLs on chromosomes 17 and 18, with genomic intervals 3 and 2 Mb, respectively, were mapped. A third QTL, with a less significant P value, was mapped to chromosome 4, with genomic interval of 2 Mb. These QTLs were named Flal1-Flal3, referring to Fatty Liver Accumulation Locus 1-3, for the QTLs on chromosomes 17, 18, and 4, respectively. Unfortunately, no QTL was mapped with males. Searching the mouse genome database suggested several candidate genes involved in hepatic fat accumulation. Our results show that susceptibility to hepatic fat accumulations is a complex trait, controlled by multiple genetic factors in female mice, but not in male

Mapping genetic determinants of host susceptibility to Pseudomonas aeruginosa lung infection in mice.

Background: P. aeruginosa is one of the top three causes of opportunistic human bacterial infections. The remarkable variability in the clinical outcomes of this infection is thought to be associated with genetic predisposition. However, the genes underlying host susceptibility to P. aeruginosa infection are still largely unknown. Results: As a step towards mapping these genes, we applied a genome wide linkage analysis approach to a mouse model. A large F2 intercross population, obtained by mating P. aeruginosa-resistant C3H/HeOuJ, and susceptible A/J mice, was used for quantitative trait locus (QTL) mapping. The F2 progenies were challenged with a P. aeruginosa clinical strain and monitored for the survival time up to 7 days post-infection, as a disease phenotype associated trait. Selected phenotypic extremes of the F2 distribution were genotyped with high-density single nucleotide polymorphic (SNP) markers, and subsequently QTL analysis was performed. A significant locus was mapped on chromosome 6 and was named P. aeruginosa infection resistance locus 1 (Pairl1). The most promising candidate genes, including Dok1, Tacr1, Cd207, Clec4f, Gp9, Gata2, Foxp1, are related to pathogen sensing, neutrophils and macrophages recruitment and inflammatory processes. Conclusions: We propose a set of genes involved in the pathogenesis of P. aeruginosa infection that may be explored to complement human studie

Evaluation of Isolated Compounds Activity from Convolvulus Arvensis Against Algae

Abstract This study includes isolation, purification, and identification of algae from different aquatic environments in Baghdad city. Nine unialgal cultures were obtained. These algal cultures included 6 species of blue-green algae (Microcystis aeruginosa, Microcystis flos-aquae, Oscillatoria limnetica, Nostoc carneum, Westillopesis prolifica, Mastigocluds lamiosus), and 3 species of green algae (Mougeotia sclaris, Scenedesmus dimorphus and Chlorella vulgaris). In addition that aerial parts from Convolvulus arvensis were collected. Terpens, alkaloids and phenols were extracted of mentioned plant, and the antialgal activity of extracts types were evaluated in 3 concentrations (5, 10, and 20 mg/ml) by wells and diffused in the agar media. Results showed that phenols extracts from C. arvensis were the most effective against isolated algae than other extracts, and terpens extracts were less effective. O. limentica was the most sensitive to attack by extracts than other algae, while N. carneum was lower sensitive, also W. prolifica, M. lamiosus were the most resistance to attack by C. arvensis extracts. Chemical composition of phenols and alkaloids were analyzed by High Performance Liquid Chromatography (HPLC) and showed that present 10 phenolic compounds, 8 alkaloid compounds in C. arvensis. Keywords: C. arvensis, Extracts, Algal control, Antialgal. ‫نبات‬ ‫من‬ ‫المعزولة‬ ‫المركبات‬ ‫فعالية‬ ‫تقيم

PREPARATION AND EVALUATION OF ULTRASOUND TRANSMISSION GEL

Objective: Formulation of an alternative ultrasound transmission gel that is of good quality using the available chemicals in Iraqi market and without any harmful effects to skin. Methods: Four formulas G1, G2, G3, and G4 with different Carbopol 934 concentrations (0.3, 0.4, 0.5, and 0.6) w/v%, respectively, were prepared and evaluated for different physicochemical characteristics including: Clarity, homogeneity, density, pH, viscosity, and spreadability tests. Other evaluations including skin irritation, microbiological, and stability tests were also performed for the selected formula along with a comparison study with the commercially available ultrasound gel (commercial gel [CG]) which was used as a control. In addition, transmission test was carried out by comparing the transmission between (CG) and (G1) with the assistance of three veterinary radiologists who did ultrasonography of bovine liver for 11 adult cattle breed, aged 3–8 years. The three veterinary radiologists were given 33 data sheets to collect results.Results: Among all the prepared formulas (G1), the formula was considered the best, due to its high clarity, very good homogeneity; its pH was equal to 6.8 which is near to skin pH. Other parameters such as density, viscosity, torque percent, and spreadability showed no significant difference (p≤0.05) with CG. Skin irritation test which was conducted on animals and humans showed no any adverse effects on skin. Microbiological test manifested that using methylparaben alone was sufficient to prevent the growth of microbes in the gel. The three veterinary radiologists found no significant difference (p≤0.05) between G1 and CG formulations. Stability study indicated that the gel was stable after storage at room temperature for 3 months.Conclusion: The overall results suggest that the selected formula (G1) can be considered a successful ultrasound gel and can be used as a good and cheap alternative of the marketed imported gel

From Functional Analysis to CAD Modelling Based on Knowledge Transformation Driven by the Design Process

Part 5: Modelling for PLMInternational audienceMost of industries currently spend too much time to find information on past product design process. This considerably reduces the time it can devote to innovation. The authors assume that the design process meta-model seems very interesting for modelling the design rational and then for accelerating information retrieval. Indeed, the model of the design process partly supports every resources involved in decision making activities (i.e. who, what, when, why, where, how). The authors therefore propose the use of a MBE architecture for driving the product modelling based on the design process model. The UML activity diagrams and the IDEFØ meta-model are linked for supporting automatic generation ofproduct models using specific transformation knowledge. The CAD model is partly generated from the product functional analysis

Development of specific primers for the detection of HVA1 from barley in transgenic durum wheat by polymerase chain reaction (PCR) technology

Genetic transformation is a widely employed tool in both basic research and commercial plant breeding programs. Its application requires that transgenes be stably integrated and expressed in the plant genome. When transgenic plants are developed, it is essential to determine which plants contain the transgene. Detection methods are usually based on amplification of the target transgene. This paper describes a development of detection method based on conventional and real time polymerase chain reaction (PCR) for simultaneous detection of barley HVA1 transgene and its transcript in transformed durum wheat. Since there exist a high homology between the barley HVA1 gene and the wheat gene, development of a specific sets of primers is needed for PCR-based characterizations, and the study of the transgene. Based on the alignment of the two genes sequences obtained from public databases, several primers were designed to detect and distinguish between the transformed and non-transformed plants. Real time PCR has been employed because of its inherent sensitivity and quantitative nature. It has been possible to design the following primers pairs F2/MMR, F2/R10 and F14/R10 as highly specific and suitable for the detection of HVA1 DNA by conventional and real-time PCR. Nonetheless, the primers used were allowed to reach high efficiencies and did not show any cross-reactivity with DNAs extracted from various plants. The sensitivity achieved was 6.4 pg. The primer pair F2/R10 was considered as highly specific for the detection of both DNA and mRNA of the HVA1 by real-time PCR. The assays proved to be accurate, specific, sensitive and sufficiently reproducible for further application in high-throughput molecular characterization of transgenic lines.Keywords: HVA1, durum wheat, transgenic plant, real time polymerase chain reaction (PCR), droughtAfrican Journal of Biotechnology, Vol. 13(4), pp. 581-592, 22 January, 201

Association of GH gene polymorphism with growth and semen traits in rabbits

[EN] Although growth hormone (GH) gene mutations are described in several species, the studies concerning their variabilities and associations with economic traits in rabbits are scarce, particularly associations with semen traits. A total of 149 rabbit bucks from five populations (V-line=36, Moshtohor line=28, APRI line=42, cross ½A½M=23, and Gabali=20) were used in the present study to identify polymorphism of c.-78 C>T single nucleotide polymorphism (SNP) of GH gene among these populations and to investigate the association of GH gene polymorphism with body weight (BW), daily weight gain (DG) and semen traits. DNA was extracted from blood samples for genotyping of c.-78 C>T SNP of GH gene based on polymerase chain reaction with the restriction fragment length polymorphism (PCR-RFLP) technique. The genetic diversity of SNP C>T of GH gene was assessed in terms of genotypic and allelic frequencies, effective number of alleles (Ne), observed (Ho) and expected (He) heterozygosity, Hardy-Weinberg equilibrium (HWE), reduction in heterozygosity due to inbreeding (FIS) and polymorphism information content (PIC). Three genotypes of TT, CC and TC of PCR product of 231 bp of GH gene were detected and all the populations were in HWE in terms of GH gene. The highest Ne was obtained for the Moshtohor line (1.978), while the lowest allelic numbers were obtained for V-line (1.715) and Gabali breed (1.800). The highest genotype frequency of GH gene was 0.48 in TT genotype of V-line, 0.21 in CC genotype of Moshtohor line, 0.67 and 0.56 in TC genotype of ½A½M and Gabali rabbits (P<0.05). The highest frequency for C allele was recorded by Moshtohor line (0.45) and the lowest frequency by Gabali (0.32). The genetic diversity scores for GH gene were intermediate (Ho=0.551, He=0.471, PIC=0.358). The values of Ho ranged from 0.444 in V-line to 0.667 in ½A½M cross, while the values of He were 0.425 in V-line and 0.508 in Moshtohor line. The values of PIC were moderate and ranged from 0.332 in V-line to 0.375 in M-line. The highest FIS was observed in Moshtohor line (0.042) and the lowest value was observed in ½A½M cross (–0.413). The CT genotype of GH gene showed the highest and significant values for body weights at 4, 8, 10 and 12 wk (542, 1131, 1465 and 1861 g) and daily gains at intervals of 4-6 and 8-10 wk (23.1 and 26.5 g). Additionally, the CT genotype recorded the highest and significant values for volume of ejaculate (1.1 mL), sperm motility (57.6%), live sperm (85.6%), normal sperm (93.1%) and sperm concentration in semen (611×106/mL), along with the lowest and significant values for dead sperms (14.4%) and abnormal sperms (6.9%).The authors are very grateful to the Central Laboratory of the Faculty of Veterinary Medicine, Benha University, Egypt for the help and support in molecular genetic analyses. This work was financially supported by the research project entitled “Genetic improvement of local rabbit breeds by using molecular genetic techniques” from the Scientific Research Fund (SRF), Benha University, Egypt.Khalil, MHE.; Zaghloul, AR.; Iraqi, MM.; El Nagar, AG.; Ramadan, SI. (2021). Association of GH gene polymorphism with growth and semen traits in rabbits. 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