Phenotypic evaluation of feed efficiency, growth and carcass traits in native turkeys

Improving feed efficiency decreases feed intake, total cost, and the environmental emission of poultry production. This study aimed to investigate different feed efficiency, growth and carcass traits between high and low feed efficiency birds in Iranian native turkeys. Growth and carcass characteristics of native turkeys were recorded. Four different feed efficiency traits, including feed conversion ratio (FCR), residual feed intake (RFI), residual body weight gain (RG), and residual intake and body weight gain (RIG) were calculated. The phenotypic correlations were calculated among feed efficiency measurements and different growth traits. High and low feed efficiency birds based on FCR were compared for growth and carcass traits. The phenotypic correlation between FCR and RFI was 0.5 and FCR was strongly correlated with RG and RIG. Breast muscle weight of high feed efficiency birds based of FCR was significantly higher than low feed efficiency birds. The results showed that phenotypic selection based on each of the feed efficiency traits will automatically progress the others, however, using FCR can be more straightforward in local farms and results in producing more beneficial turkeys with better growth and carcass features

Expression of Serine Biosynthesis Pathway Genes in Breast Muscles of Iranian Native Turkeys with Divergent Feed Efficiency

Introduction: Feed is the main cost part of poultry production. High feed efficiency poultry produce less feed and less excrement per unit weight gain. Therefore, a comprehensive understanding of the biological mechanisms that control feed efficiency is crucial for the development of optimal breeding and selection strategies. The serine biosynthesis pathway is one of the most important pathways in animals with high feed efficiency. The aim of this study was to investigate the expression of PHGDH, PSAT1 and PSPH genes by real-time PCR in Iranian native turkeys with high and low feed efficiencies.Materials and Methods: Iranian native male turkeys (n=500) were reared up to 20 weeks of age under standard production guidelines. Then 75 turkeys were randomly selected and placed in separate cages with free access to water and feed from 20 to 24 weeks. Turkeys were ranked based on feed conversion ratio (FCR) and three turkeys with the highest and three turkeys with lowest feed efficiency were selected as high feed efficiency (HFE) and low feed efficiency (LFE) birds, respectively. After slaughter of turkeys, RNA was extracted from breast tissue. Quantity and purity of the extracted RNAs were determined using a nanodrop device and its quality was evaluated using 1% agarose gel electrophoresis. Sequences of PSPH, PHGDH, PSAT1 and RSP7 genes were collected from the NCBI database. The primer was designed using Primer Premier version 5 software. All primers were synthesized by Sinaclon (Iran). In this study, RSP7 gene was used as a reference gene. Then, cDNA synthesis was performed. The best amplification temperature for simultaneous amplification of target and reference genes was determined. Samples were amplified for each gene with 3 replications using real-time PCR reaction. Significance level between treatments for each gene was determined separately using t-test in SAS software version 9.2 (P<0.05).Results and Discussion: Results of ultraviolet light absorption measurements at 260 and 280 nm by the nanodrop device showed that the quantity and quality of RNA extracted from the breast muscle samples were of high purity and not contaminated. The range of RNA concentration of the extracted samples was between 480 to 962 ng/μl and the ratio of absorption at 260 and 280 wavelength was about 2.1, which indicates the good quality of the extracted RNAs. The most suitable temperature was selected for specific binding of primers and simultaneous amplification of target genes and temperature control of 58 °C. To investigate and confirm the specificity of replication, melting curves were created to ensure the specificity of the amplified products, the absence of non-specific bands and secondary structures such as hairpin and primer-dimer structures. The results showed that there was only one narrow peak for each gene. The results of studying the expression of serine biosynthesis pathway genes (PSPH, PHGDH and PSAT1) showed that the expression level of these genes in HFE male turkeys was significantly higher than LFE male. Higher expression of PSPH, PHGDH and PSAT1 genes in HFE animals than in LFE animals indicates activation of the serine amino acid biosynthesis pathway, which itself can provide precursors for the Krebs cycle and purine biosynthesis. Glucose is the main source of metabolic energy in the body. When glucose enters the cell, glycolysis begins in the cytoplasm. The pathway of glycolysis and Glutamine catabolism produces an intermediate metabolite called 3-phosphoglycerate, which is gradually catalyzed to serine by PHGDH, PSAT1, and PSPH. Eventually serine is converted to glycine. Activation of this pathway indicates the higher ability of HFE animals to make better use of energy sources such as glucose, which increases protein production in breast muscle tissue and enhances volume and weight of muscle tissue in HFE turkeys.Conclusion: The results of this study showed that the expression of serine biosynthesis pathway genes (PSPH, PHGDH and PSAT1) was significantly higher in high feed efficiency turkeys than in low feed efficiency turkeys. In fact, these results at the level of molecular biology show that turkeys with higher feed efficiency cultivate better use of energy received from feed. Activation of this pathway increases the biosynthesis of various amino acids and thus increases protein and muscle mass in birds. The results of this study can be a promising window to introduce genes that affect feed efficiency in order to further investigate the population and larger flocks of birds

Transcriptome analysis showed differences of two purebred cattle and their crossbreds

The consequences of a cattle crossbreeding programme on the genes expression, signalling and metabolic pathways, molecular networks, and biological functions is still indistinctive. In this study differences of five cattle populations in a crossbreeding programme were studied using high throughput sequencing technology to characterise their transcriptome. Holstein (Bos Taurus origin) and Taleshi (Bos indicus origin) as purebred cattle were compared with their crossbreds including 50% sire Taleshi and dam Holstein (50CSN), 50% sire Holstein and dam Taleshi (50CSH) and 75% Holstein (75C). Differentially expressed genes (DEGs) and their related enriched metabolic pathways, transcription up-stream regulators and biological functions were studied by bioinformatics tools of transcriptome analysis. Total expressed transcripts in all populations were 72,812 with 22,627 annotated genes. We found 2262 DEGs in which 251 genes were uniquely expressed in purebreds or crossbreds. Functional analysis of DEGs showed that the immune and inflammatory responses were the most highly-impacted pathways and functions. Among all significantly enriched pathways, eukaryotic translation initiation factor-2 signalling had the highest activation Z-score (5.3) in crossbred compared to purebred cattle. The majority of up-stream regulators of genes including transcription regulators and cytokines were differentially expressed among populations in which their activation Z-score in purebred was more than crossbred cattle. Crossing of Holstein with Taleshi breed resulted lower activity of pathways related to immunity and inflammatory responses. The analysis revealed that the most important differences between studied genotypes, especially between purebred and crossbred cattle, were related to immune function

Transcriptome Analysis of Breast Muscle Reveals Pathways Related to Protein Deposition in High Feed Efficiency of Native Turkeys

Feed efficiency is important due to the high cost of food, which accounts for about 70% of the total cost of a turkey breeding system. Native poultry are an important genetic resource in poultry breeding programs. This study aimed to conduct a global transcriptome analysis of native male turkeys which have been phenotyped for high and low feed efficiency. Feed efficiency traits were recorded during the experimental period. After slaughter, the three most efficient and three least efficient male turkeys were selected for RNA-Seq analysis. A total of 365 genes with different expressions in muscle tissue were identified between turkeys with a high feed efficiency compared to turkeys with a low feed efficiency. In the pathway analysis of up-regulated genes, major pathways included the &ldquo;metabolism of glycine, serine, and threonine&rdquo;; the &ldquo;adipocytokine signaling pathway&rdquo; and the &ldquo;biosynthesis of amino acids&rdquo;. In the pathway analysis of down-regulated genes, the major pathways included &ldquo;dorso-ventral axis formation&rdquo; and &ldquo;actin cytoskeleton regulation&rdquo;. In addition, gene set enrichment analyses were performed, which showed that high feed efficiency birds exhibit an increased expression of genes related to the biosynthesis of amino acids and low feed efficiency birds an increased expression of genes related to the immune response. Furthermore, functional analysis and protein network interaction analysis revealed that genes including GATM, PSAT1, PSPH, PHGDH, VCAM1, CD44, KRAS, SRC, CAV3, NEDD9, and PTPRQ were key genes for feed efficiency. These key genes may be good potential candidates for biomarkers of feed efficiency in genetic selection in turkeys

Runs of homozygosity and cross-generational inbreeding of Iranian fat-tailed sheep

The Lori-Bakhtiari fat-tailed sheep is one of the most important heavyweight native breeds of Iran. The breed is robust and well-adapted to semi-arid regions and an important resource for smallholder farms. An established nucleus-based breeding scheme is used to improve their production traits but there is an indication of inbreeding depression and loss of genetic diversity due to selection. Here, we estimated the inbreeding levels and the distribution of runs of homozygosity (ROH) islands in 122 multi-generational female Lori-Bakhtiari from different half-sib families selected from a breeding station that were genotyped on the 50k array. A total of 2404 ROH islands were identified. On average, there were 19.70 ± 1.4 ROH per individual ranging between 6 and 41. The mean length of the ROH was 4.1 ± 0.14 Mb. There were 1999 short ROH of length 1-6 Mb and another 300 in the 6-12 Mb range. Additionally long ROH indicative of inbreeding were found in the ranges of 12-24 Mb (95) and 24-48 Mb (10). The average inbreeding coefficient (FROH) was 0.031 ± 0.003 with estimates varying from 0.006 to 0.083. Across generations, FROH increased from 0.019 ± 0.012 to 0.036 ± 0.007. Signatures of selection were identified on chromosomes 2, 6, and 10, encompassing 55 genes and 23 QTL associated with production traits. Inbreeding coefficients are currently within acceptable levels but across generations, inbreeding is increasing due to selection. The breeding program needs to actively monitor future inbreeding rates and ensure that the breed maintains or improves on its current levels of environmental adaptation

Investigating the Polymorphism of Bone Morphogenetic Protein Receptor-1B (BMPR1B) Gene in Markhoz Goat Breed

Reproductive traits in livestock species are genetically controlled by the action of single genes with a major effect, commonly known as fecundity genes. One of the genes involved in controlling prolificacy is BMPR1B (FecB), a dominant autosomal gene located in chromosome 6 responsible for the fecundity and twinning rate in sheep and goat species. Markhoz goat is a valuable Iranian genetic resource endangered by extinction. Increasing the genetic variability and reproductive performances of Markhoz goat could preserve and enhance its economic value. This study was carried out to detect possible polymorphisms in BMPR1B gene in a sample of 100 Markhoz goats from Iran. DNA samples were screened by PCR&ndash;RFLP to assess the presence of the previously reported FecB mutation. Finally, the amplicons from seven goats out of the 100 samples were sequenced. The results showed that all the analyzed individuals did not carry the previously reported FecB mutant allele. However, our findings revealed two novel possible mutations in exon 8 of BMPR1B gene (775A &gt; G and 777G &gt; A) that need further investigations

Investigating the polymorphism of bone morphogenetic protein receptor-1B (BMPR1B) gene in Markhoz goat breed

Reproductive traits in livestock species are genetically controlled by the action of single genes with a major effect, commonly known as fecundity genes. One of the genes involved in controlling prolificacy is BMPR1B (FecB), a dominant autosomal gene located in chromosome 6 responsible for the fecundity and twinning rate in sheep and goat species. Markhoz goat is a valuable Iranian genetic resource endangered by extinction. Increasing the genetic variability and reproductive performances of Markhoz goat could preserve and enhance its economic value. This study was carried out to detect possible polymorphisms in BMPR1B gene in a sample of 100 Markhoz goats from Iran. DNA samples were screened by PCR–RFLP to assess the presence of the previously reported FecB mutation. Finally, the amplicons from seven goats out of the 100 samples were sequenced. The results showed that all the analyzed individuals did not carry the previously reported FecB mutant allele. However, our findings revealed two novel possible mutations in exon 8 of BMPR1B gene (775A&gt;G and 777G&gt;A) that need further investigations.Simple Summary TheBMPR1Bgene is one of the major genes involved in controlling prolificacy in small ruminant species. The research was conducted to detect possible polymorphisms inBMPR1Bgene in a population of Markhoz goats, a valuable genetic resource of Iran. The results showed that all the analyzed individuals did not carry the previously reported FecB mutant allele. Moreover, we reported for the first time two novel possible mutations in exon 8 ofBMPR1Bgene that are noteworthy of further investigation. Reproductive traits in livestock species are genetically controlled by the action of single genes with a major effect, commonly known as fecundity genes. One of the genes involved in controlling prolificacy isBMPR1B(FecB), a dominant autosomal gene located in chromosome 6 responsible for the fecundity and twinning rate in sheep and goat species. Markhoz goat is a valuable Iranian genetic resource endangered by extinction. Increasing the genetic variability and reproductive performances of Markhoz goat could preserve and enhance its economic value. This study was carried out to detect possible polymorphisms inBMPR1Bgene in a sample of 100 Markhoz goats from Iran. DNA samples were screened by PCR-RFLP to assess the presence of the previously reported FecB mutation. Finally, the amplicons from seven goats out of the 100 samples were sequenced. The results showed that all the analyzed individuals did not carry the previously reported FecB mutant allele. However, our findings revealed two novel possible mutations in exon 8 ofBMPR1Bgene (775A &gt; G and 777G &gt; A) that need further investigations