Chicken Ecotypes Research Articles

The Influence of Trait Preferences and Breeding Practices on Local Chicken Genetic Resource Conservation in Igunga District, Tanzania

A cross-sectional study was conducted to determine the influence of farmers’ trait preferences and breeding practices on local chicken genetic resource conservation in Igunga District, Tabora Region of Tanzania. The study used proportionate random sampling to obtain 384 respondents in ten study villages within two wards. Data were collected through a household survey, key informant interviews (n=5), and focus group discussions (n=10). Descriptive statistics such as mean, percentage and frequencies are used to present the findings. Chi-square establishes the association between variables. The relative importance indices (RII) model determines the level of importance of preferred local chicken traits. The findings indicates that natural mating and slaughter of the chickens with undesirable characteristics as main breeding methods and are statistically significant in between the two wards (p<0.05). Furthermore, findings show that Kuchi is the most preferred local chicken ecotype due to its large body weight and size. Findings on RII on breeding hen indicates that hen egg number with RII=0.9 as the most preferred trait (first rank) followed by hatchability with RII=0.87 (second rank) and mothering behavior with RII =0.86 (third rank). Furthermore, the cock body size ranks first with RII=0.9 followed by cock weight as a second rank with RII = 0.86 and cock disease resistance which ranks third with RII=0.85. Government officials affirm that local chickens are more resilient to diseases than other breeds. The local chicken traders contend that the market value of the local chickens depends on large body weight or frame and plumage color whereas farmers confirm that the preferred breed and traits is focused on economic motives. The study suggests that characterization of local chickens is an important step prior to setting strategies for breeding, utilization and conservation of the resources.

Testing of Hardy-Weinberg Equilibrium in Population of Two Nigerian Local Chicken Ecotypes Base on Location

Test of deviation from Hardy-Weinberg equilibrium expectation base on location of the Tiv and Fulani local chicken ecotypes of Nigeria was undertaken using eighty (80) matured birds (40 birds each for Tiv and Fulani ecotypes). Blood samples were collected from five locations each of the ecotype to determine their blood protein. Blood protein loci namely: haemoglobin, albumen, transferrin and carbonic anhydrase were determine using electrophoresis. Data collected were analyzed using popgene version 1.31. The result revealed significant deviations (P<0.05) from Hardy-Weinberg expectations in the two ecotypes except in the Fulani ecotype were haemoglobin did not deviate significantly. Based on location, there were no significant (P>0.05) deviation from Hardy-Weinberg expectations in the Fulani ecotype except in location 4 were Hb, Al and Ca as well as location 5 where Al and Ca were significant. Allelic frequencies of albumin showed significant (P<0.05) deviation from Hardy-Weinberg expectations at locations 1 and 5 while allelic frequencies of transferrin deviated significantly (P<0.05) from the Hardy-Weinberg frequency at location 5. In the Tiv ecotype, albumin showed the highest significant (P<0.05) deviation from the Hardy-Weinberg expectations in all locations. The allelic frequencies of transferrin did not differ significantly (P>0.05) from the Hardy-Weinberg expectations. From the finding of this research, it was concluded that the deviation from Hardy-Weinberg expectations at the four blood proteins loci of the two ecotypes indicated that the Tiv and the Fulani chicken populations are variable in their genome and that there are chances of genetic improvement when crossed between themselves across location or with exotic breeds. Generally, these findings provide the fundamental step in the direction of judicious decision-making before the development of genetic enhancement and preservation programmes without interfering with the uniqueness of the Tiv............

Genetic Analyses of Response of Local Ghanaian Tanzanian Chicken Ecotypes to a Natural Challenge with Velogenic Newcastle Disease Virus.

Newcastle disease is a devastating poultry disease that often causes significant economic losses in poultry in the developing countries of Africa, Asia, as well as South and Central America. Velogenic Newcastle disease virus (NDV) outbreaks are associated with high mortalities, which can threaten household livelihoods, especially in the rural areas, and lead to loss of high-quality proteins in the form of meat and eggs, as well as household purchasing power. In this study, we exposed unvaccinated Ghanaian and Tanzanian chickens of six local ecotypes to velogenic NDV strains, measured NDV response traits, sequenced their DNA on a genotyping-by-sequencing platform, and performed variance component analyses. The collected phenotypes included: growth rates (pre- and post-exposure); lesion scores (gross lesion severity) in the trachea, proventriculus, intestine, and cecal tonsils; natural antibody levels; anti-NDV antibody levels at 7 days post exposure (dpe); tear and cloacal viral load at 2, 4, and 6 dpe; and survival time. Heritability estimates were low to moderate, ranging from 0.11 for average lesion scores to 0.36 for pre-exposure growth rate. Heritability estimates for survival time were 0.23 and 0.27 for the Tanzanian and Ghanaian ecotypes, respectively. Similar heritability estimates were observed when data were analyzed either separately or combined for the two countries. Survival time was genetically negatively correlated with lesion scores and with viral load. Results suggested that response to mesogenic or velogenic NDV of these local chicken ecotypes could be improved by selective breeding. Chickens that are more resilient to velogenic NDV can improve household livelihoods in developing countries.

Ecological niche modelling as a tool to identify candidate indigenous chicken ecotypes of Tigray (Ethiopia)

The Tigray region is an ancient entry route for the domestic chickens into Africa. The oldest African chicken bones were found in this region at Mezber, a pre-Aksumite rural farming settlement. They were dated to around 800–400 BCE. Since then, the farming communities of the region have integrated chicken into their livelihoods. The region is also recognised for its high chicken-to-human population ratio and diverse and complex geography, ranging from 500 to 4,000 m above sea level (m.a.s.l.). More than 15 agro-ecological zones have been described. Following exotic chicken introductions, the proportion of indigenous chicken is now 70% only in the region. It calls for the characterisation of indigenous Tigrayan chicken ecotypes and their habitats. This study reports an Ecological Niche Modelling using MaxEnt to characterise the habitats of 16 indigenous village chicken populations of Tigray. A total of 34 ecological and landscape variables: climatic (22), soil (eight), vegetation, and land cover (four), were included. We applied Principal Component Analysis correlation, and MaxentVariableSelection procedures to select the most contributing and uncorrelated variables. The selected variables were three climatic (bio5 = maximum temperature of the warmest month, bio8 = mean temperature of the wettest quarter, bio13 = precipitation of the wettest month), three vegetation and land cover (grassland, forest land, and cultivated land proportional areas), and one soil (clay content). Following our analysis, we identified four main chicken agro-ecologies defining four candidates indigenous Tigrayan chicken ecotypes. The study provides baseline information for phenotypic and genetic characterisation as well as conservation interventions of indigenous Tigrayan chickens.

An exploratory study on differences in maternal care between two ecotypes of Nigerian indigenous chicken hens

The Yoruba (YRE) and Fulani (FLE) are the two notable indigenous chicken ecotypes in Nigeria. They exhibit broodiness and post-hatch care of their chicks. Studies on welfare, productivity, and maternal behaviors of these two ecotypes are scarce, hence the need for this study. Separate flocks of these ecotypes were housed intensively and hens that showed broodiness (ten YRE and five FLE) were monitored. Brooding behaviors were monitored for 3 days in the 1st and 2nd weeks of brooding and daily in the 3rd week of brooding for 6 h/day (07:00–09:00 h, 11:00–13:00 h, and 15:00–17:00 h). During brooding, surface body temperatures (eye, brood patch and under the wings), egg temperature and body weight of the hens were measured. Chicks hatched (44 chicks from the YRE and 24 chicks from the FLE) by these hens were subjected to tonic immobility tests on the 7th, 14th, and 21st days post-hatch and to a simulated predator test on the 8th, 15th, and 22nd days post-hatch to determine their level of fear. In each ecotype, brooding behaviors did not change over the three weeks, but the YRE hens spent longer time sitting on their eggs at the 2nd (U = 5.000, z = −2.454, P = 0.014) and 3rd (U = 9.000, z = −1.961, P = 0.050) week of brooding. The surface body temperatures of both ecotypes, egg temperature, and relative weekly weight loss were similar over the brooding period, but relative weekly weight loss was greater (P < 0.05) at the 3rd than 1st and 2nd week of brooding. The surface body temperatures were positively correlated (P < 0.01) with egg temperature. In both ecotypes, attempts to induce and duration of tonic immobility were similar over the test periods but on the 7th day post-hatch, the duration of tonic immobility was longer (U = 323.000, z = −2.632, P = 0.008) and on the 14th day post-hatch, the number of attempts to induce tonic immobility was less (U = 332.000, z = −2.630, P = 0.009) in the YRE chicks. In conclusion, YRE hens sat more on the eggs and their chicks were more fearful.

In-situ morphological characterization of indigenous chicken Ecotypes in Uganda

Genetic improvement of indigenous chickens (IC) is hindered by limited knowledge on the various chicken Ecotypes. This study characterized and assessed the genetic diversity of nine (9) IC Ecotypes based on quantitative morphological traits. A total of 576 IC (288 cocks and 288 hens) were sampled from 288 households across the 9 agro-ecological zones of Uganda. Data on linear morphological traits and live weight of IC were collected using a field guide developed by African Union Inter-African Bureau for Animal Resources (AU-IBAR, 2015). Over-all, body live weight (LWT), shank/tarsus length (SL), drumstick length (DL), thorax circumference (TC) and body length (BL) of IC varied significantly (P < 0.05) across Ecotypes except tarsus circumference (TAC) of cocks. Cocks and hens on average weighed 2.2 ± 0.53 and 1.6 ± 0.58 kg respectively. On average, SL, DL, TC, BL, TAC was 9.8 ± 1.23, 4.9 ± 2.50, 16.2 ± 1.63, 38.4 ± 5.96, 24.7 ± 4.93 cm for cocks and 7.8 ± 1.04, 3.9 ± 0.53, 13.2 ± 1.42, 33.8 ± 5.29, 21.3 ± 4.37 cm for hens respectively. Body weight and linear morphological traits except TAC were significantly (P < 0.05) influenced by Ecotype. Principal component analysis based on live body weight and morphological linear traits did not identify any distinct chicken Ecotype. The disparity in weight estimation models further emphasizes the ecologically induced variations across Ecotypes. Therefore, the current study confirms the morphological and more so genetic similarity implying genetic improvement can be achieved through selection of superior IC across Ecotypes.

Phenotypic characterization and production systems of indigenous chickens in urban, peri urban and rural area of the west Harerghe zone, Ethiopia

The study was conducted to characterize the indigenous chicken ecotypes and identify the production system of the owners across different locations. The three districts of West Hararghe zone of Oromia region, Gamachis, Tullo and Ciro district were purposely selected to represent high-altitude, mid-altitude and low-altitude agro-ecologies, respectively. Three kebeles from different locations (urban, peri-urban and rural) were selected purposely in each district that makes up a total of 9 kebeles as primary sampling units for the study. About 20 rural households (HH) per kebeles were selected randomly and additional three focus groups one per district was formed to strength the ideas of the respondents. A total of 180 HHs (60 HHs per urban, peri-urban and rural locations) were interviewed for primary data collection. Productive and reproductive performance, breeding practice, and major constraints of chicken production were addressed by semi-structured questionnaire and checklists. Additionally, field observations and focus group discussions were practiced. Whereas, measurable traits like body weight (BW), body length (BL), chest circumference (CC), wing span (WS), shank length (SL), comb length (CL), comb width (CW), wattle length (WL), earlobe length (EL), height at back (HB) and height at comb(HC)were considered for the study of 420 mature chickens morphological characteristics. The data were analyzed using General Linear Model (GLM) of SAS (version 9.1.3).Also SPSS (version 20) and index methods were used to analyze qualitative data and to rank priority setup of the breeding objectives and to detect the major constraints respectively. The overall mean for body weight obtained for mature chicken was 1.33±0.009 kg which showed a significant difference (p

A Comparable genetic diversity between chicken ecotypes of different zones using DNA barcoding

Objectives: The purpose of the current study was to verify the reliability of COI bar- codes in the assessment of genetic diversity of two ecotypes from different ecozones.&#x0D; Methods: The DNA sequences of cytochrome oxidase I (COI) barcodes of 50 hens belonging to two ecotypes of Ismalia Egypt (ISM) and Taif Saudi Arabia (TA) were isolated and analyzed.&#x0D; Results: This study results showed that no noticeable great differences among all barcode’s sequences of both ecotypes. The aver- age length of both ecotypes was 589 bp. ISM ecotypes have a relatively wider length range. The overall mean of GC% content was 48±0.01. Both ecotypes have the same number of sites 548 bp. ISM ecotype has 523 monomorphic sites whereas TA ecotype has slightly fewer monomorphic sites 517. The ISM ecotype has 7 singleton sites and 18 Parsimony informative sites. TA ecotype has little more polymorphic, that is 12 singleton sites and 19 Par- simony informative sites. The number of mutations (η) was larger in ISM (46) compared to 38 mutations for TA ecotype. Both ecotypes had the same number of Haplotypes (25), and haplotypes diversity (1) as well as the variance of haplotype diversity.&#x0D; Conclusion: These results indicated a comparable level of genetic diversity of both ecotypes, which in turn may refer to a similarity of evolutionary forces that affect both ecotypes. Based on the present results, COI gene can be used in barcoding. The COI provides an objective the foundation for identification of ecotypes and therefore could be used for a rapid establishment of a variety of identifications.

Genetic Diversity and Population Structure of Local Chicken Ecotypes in Burkina Faso Using Microsatellite Markers.

The objective of this study was to investigate the genetic diversity and population structure of local chicken ecotypes from Burkina Faso using microsatellite markers. A total of 71 individuals representing local chicken populations from the Centre-East (18), Centre-North (17), Sahel (18) and South-West (18) were used to estimate genetic diversity indices, population structure and phylogenetic relationships using 20 selected polymorphic microsatellite markers. The number of alleles, mean number of alleles, mean of observed and expected heterozygosity and polymorphic information content were 127, 6.35, 0.391, 0.521, 0.539 and 0.541, respectively. The estimated overall fixation index between loci (F), among populations (FIS) and inbreeding coefficient within chicken ecotypes were 0.239, 0.267 and 0.243, respectively. Analysis of the molecular variance revealed that 77% of the total genetic diversity was attributed to within-population variation and the remaining 1% and 22% were attributed to among-regions differentiation (FST) and among-individual differentiation (FIT), respectively. The highest pairwise genetic distance (0.026) was found between the local Konde ecotype and those from the Centre-North region while the lowest distance was observed between local chickens from the Sahel and the Centre-North regions (0.003). Neighbour-joining phylogenetic tree and principal component discriminant analyses confirmed the observed genetic distances between populations. The results show that local chickens in Burkina Faso have a rich genetic diversity with little differentiation between the studied populations. This study provides important information on measures of genetic diversity that could help in the design and implementation of future genetic improvement and conservation programs for local chickens in Burkina Faso.

Phenotypic Characterization of Indigenous Chicken Ecotypes in Selected Districts of Bench Maji Zone, South West Ethiopia

Phenotypic Characterization of Indigenous Chicken Ecotypes in Selected Districts of Bench Maji Zone, South West Ethiopia

Effects of Hexane Extract of Garlic on Hematological, Biochemical and Histological Parameters in F1 Crossbred Chicks Non-Infected and Infected with Salmonella typhimurium

An experiment was undertaken to evaluate the effects of garlic extract on hematological, biochemical, and histopathological profiles in F1 crossbred chicks (White Leghorn cops × Nigerian Heavy Ecotype chickens) non-infected and infected with Salmonella typhimurium. This experiment was carried out to contribute to the genetic improvement of local Nigerian chickens while controlling salmonellosis and combating antibiotic resistance. Two hundred and forty (240) chicks at two weeks old were randomly divided into six treatments: T1 (No Salmonella and no garlic), T2 (garlic only), T3 (Ciprofloxacin only), T4 (Salmonella + Ciprofloxacin), T5 (Salmonella + garlic) and T6 (Salmonella without garlic or ciprofloxacin) and reared for six days. On day seven, birds were sacrificed, and blood samples were collected for hematology and biochemistry analysis, while liver and small intestines were also collected for histopathology. Data obtained were subjected to analysis of variance (ANOVA), and were means were found to be significant, Duncan’s New Multiple Range Test was used to separate the means at a 5% probability level. The results revealed that white blood cell counts, neutrophils percentage, liver enzymes, total protein, and the weight of organs increased significantly on T6. In contrast, packed cell volume, red blood cell counts, and hemoglobin decreased significantly. Liver and small intestines damage were also observed. However, feeding birds with garlic counteracted the effect of ST on those parameters. It can be concluded that hexane extract of garlic can alleviate the harmful effect of ST in birds’ systems and, thus, used in Poultry Farms against antibiotic resistance.

Genetic diversity and selection signatures within the major histocompatibility complex of local chicken ecotypes in Kenya

Diseases remain a major challenge in chicken population leading to reduced performance and economic losses. Whenever possible, chicken population should be reared under production systems with minimum predisposing factors to diseases and other shortcomings during their productive lifetime. Selection for resistance is an attractive option when responding to the diseases challenge. The chicken major histocompatibility complex (MHC) is a highly polymorphic region associated with immune response and disease resistance. The aim of this study was to investigate genetic diversity and as well as identify signatures of selection within the MHC, which help local chicken ecotypes to withstand disease and environmental challenges. A total of eight local chicken ecotype populations from different ecological zones in Kenya and two commercial layers (CL) chicken populations were assessed using single nucleotide polymorphisms (SNPs). Principal component analysis (PCA) showed that the two populations, local chicken ecotypes and commercial chickens were distinct. Expected heterozygosity ranged from 0.21 to 0.28 in local chicken ecotypes and was 0.26 in commercial layers. As expected, inbreeding was much higher in commercial chicken layers at 0.51 - 0.64 than indigenous chickens at 0.04 - 0.27. Selection signature analysis using fixation index (FST) detected two major regions of divergence in commercial and indigenous chickens, within the MHC region mapping to seven genes: KIFC1, ZNF 692, TRIM 7, TRIM 7.2, TRIM 39.2, BLEC 3 and YLEC 1, in local chicken ecotypes which are associated with immune response and disease resistance. This result shows that local chicken ecotypes possess significant genetic diversity within the MHC region, which can be exploited to improve the chicken breeds for disease resistance. However, a comprehensive study using a larger sample size is needed to provide more insight on the viability of the MHC region.

Morphological and morphometric features of indigenous chicken in Southwest Ethiopia

Morphological and morphometric characterization of indigenous chicken ecotypes were carried out in West-Omo zone of Southwest Ethiopia. Nine qualitative and fifteen quantitative traits were observed/ measured from 660 matured chickens of both sexes. The data was analysed using SPSS version 21 and SAS version 9.1. Majority of the qualitative and quantitative traits were significantly influenced by sex and agro-ecological zones. The predominant plumage color, feather distribution, shank color, skin color, ear-lobe color, eye color, head shape, comb type, and feather morphology were red (38.4%), normal (96.2%), yellow (45%), white (48.8%), red (42.1%), red (28.6%), flat plain (94.4%), single (64.7%) and normal (100%). The body weight of matured male chickens in highland, mid-altitude and lowland agro-ecologies was 2.1±0.02 kg, 2.2±0.05 kg, and 2.0±0.03 kg, respectively, while females weighed 1.4±0.01 kg, 1.5±0.00 kg, and 1.4±0.01 kg in highland, mid-altitude, and lowland agro-ecologies, respectively. Males were also superior to females in terms of body length (BL) values of 42.0 ± 0.19cm and 37.7 ± 0.06cm, respectively. The prediction of body weight could be based on regression equation y = -1.02 + 0.10 CC (chest circumference) for male and y= -1.26 + 0.07BL of hen in highland altitude, y = -1.06+ 0.11 CC of male and y= -0.78+ 0.05 BL of hen in mid-altitude and similarly y = -0.90 +0.10 CC in lowland male and y= -1.33 + 0.07 BL of lowland hen. Therefore, chest circumference for males and body length for females were the best variables to predict the body weight of chickens than other variables. The current finding shows there was heterogeneity in a population of indigenous chickens in the studied agro-ecology. This gives an opportunity for genetic improvement of indigenous chickens within a population.

Genetic diversity and signatures of selection for heat tolerance and immune response in Iranian native chickens

BackgroundUnderstanding how evolutionary forces relating to climate have shaped the patterns of genetic variation within and between species is a fundamental pursuit in biology. Iranian indigenous chickens have evolved genetic adaptations to their local environmental conditions, such as hot and arid regions. In the present study, we provide a population genome landscape of genetic variations in 72 chickens representing nine Iranian indigenous ecotypes (Creeper, Isfahan, Lari, Marand, Mashhad, Naked neck, Sari, Shiraz and Yazd) and two commercial lines (White Leghorn and Arian). We further performed comparative population genomics to evaluate the genetic basis underlying variation in the adaptation to hot climate and immune response in indigenous chicken ecotypes. To detect genomic signatures of adaptation, we applied nucleotide diversity (θπ) and FST statistical measurements, and further analyzed the results to find genomic regions under selection for hot adaptation and immune response-related traits.ResultsWe assessed the relationship between the genetic diversity of indigenous chicken ecotypes and their genetic distances to two different commercial lines. The results of genetic structure analysis revealed clustering of indigenous chickens in agreement with their geographic origin. Among all studied chicken groups, the highest level of linkage disequilibrium (LD) (~ 0.70) was observed in White Leghorn group at marker pairs distance of 1 Kb. The results from admixture analysis demonstrated evidence of shared ancestry between Arian individuals and indigenous chickens, especially those from the north of the country. Our search for potential genomic regions under selection in indigenous chicken ecotypes revealed several immune response and heat shock protein-related genes, such as HSP70, HSPA9, HSPH1, HSP90AB1 and PLCB4 that have been previously unknown to be involved in environmental-adaptive traits. In addition, we found some other candidate loci on different chromosomes probably related with hot adaptation and immune response-related traits.ConclusionsThe work provides crucial insights into the structural variation in the genome of Iranian indigenous chicken ecotypes, which up to now has not been genetically investigated. Several genes were identified as candidates for drought, heat tolerance, immune response and other phenotypic traits. These candidate genes may be helpful targets for understanding of the molecular basis of adaptation to hot environmental climate and as such they should be used in chicken breeding programs to select more efficient breeds for desert climate.

Response of three local chicken ecotypes of Ghana to lentogenic and velogenic Newcastle disease virus challenge.

This study was carried out to assess the response of three Ghanaian local chicken ecotypes to LaSota (lentogenic) and virulent field strains of Newcastle disease virus (NDV). Local chickens sampled from the Interior Savannah (IS), Forest (FO) and Coastal Savannah (CS) agro-ecological zones were bred and their offspring were challenged with LaSota NDV at 4weeks of age. The LaSota challenge was replicated four times with different chicken groups. A total of 1438 chicks comprising 509 Coastal Savannah, 518 Forest and 411 Interior Savannah ecotypes were used. Pre- and post-challenge anti-NDV antibody titre levels were determined via ELISA assays. A second trial was conducted by introducing sick birds infected with virulent NDV to a flock of immunologically naïve chickens at 4weeks old. Body weights were measured pre- and post-infection. Sex of the chickens was determined using a molecular method. In both trials, there was no significant difference among ecotypes in body weight and growth rate. In the LaSota trial, anti-NDV antibody titre did not differ by ecotype or sex. However, there was a positive linear relationship between body weight and antibody titre. In the velogenic NDV trial, survivability and lesion scores were similar among the three ecotypes. This study confirms that a relatively high dose of LaSota (NDV) challenge has no undesirable effect on Ghanaian local chicken ecotypes. All three Ghanaian local chicken ecotypes were susceptible to velogenic NDV challenge. Resistance to NDV by Ghanaian local chickens appears to be determined more by the individual's genetic makeup than by their ecotype.

Morphological variations in qualitative and quantitative traits of Fulani ecotype chickens in Nigeria

The study of Fulani ecotype (indigenous) chicken becomes necessary for proper understanding of its potentials for future breeding programmes in Nigeria. Sixty adult Fulani ecotype chickens comprising 22 males and 38 females were sourced from the Fulani kraal at Opeji in Odeda Local Government area of Ogun State and used to determine their qualitative and quantitative traits. Twenty (20) cocks out of the original 22 were selected randomly from the population for semen quality assessment. Results indicated that polydactyly was observed on 26.67% of the population. Brown and dark brown plumage colours were dominant and had an occurrence of 48.34% and 33.33%, respectively. Comb type was predominantly single (85%) while 46.67% of the population had Spur. Plumage colour influenced (p&lt;0.05) comb length, comb width, earlobe width and tail length while shank colour had significant (p&lt;0.05) effect on earlobe length, wattle length, wattle width, tail length. Plumage colour had significant (p&lt;0.05-0.01) effect on sperm motility, semen pH, sperm concentration and semen volume but not (p&gt;0.05) on livability and abnormality. Brown plumage had the highest (p&lt;0.05) sperm motility (88.50?0.89%) and pH (7.01?0.01) which was similar to brown black. Fulani cock with light brown plumage colour had the highest (p&lt;0.05) sperm concentration (1.90?0.11?109/ml) while dark brown had the least value 1.54?0.11? 109/ml. Light brown chicken recorded higher (p&lt;0.05) semen volume (0.21?0.01/ml) when compared with the dark brown chicken (0.14?0.01/ml). Medium to high positive correlations were observed among all linear body measurements. The study concluded that there existed high phenotypic diversity in Fulani chickens and could be exploited for improved breeding and conservation programmes in Nigeria. The body weight and other linear body measurements of the chickens are highly and positively correlated. However, lighter plumage Fulani ecotype cocks could be adopted in multiplication program where semen motility and concentration are paramount.

Molecular Evolution of Prolactin Gene Single Nucleotide Polymorphisms in Nigerian Chicken Ecotypes and their Association with Light Ecotype Chickens’ Egg Traits

Molecular Evolution of Prolactin Gene Single Nucleotide Polymorphisms in Nigerian Chicken Ecotypes and their Association with Light Ecotype Chickens’ Egg Traits

Effects of heat stress and a low energy diet on blood parameters and liver hsp70 and iNOS gene expressions in local chickens

Two experiments were conducted to compare effects of heat stress and its combination with low dietary energy on blood indices, liver hsp70 and iNOS gene expressions in three Tanzanian local chicken ecotypes. In experiment one, five weeks old Kuchi (K), Ching'wekwe (C) and Morogoro medium (M) were randomly allocated to separate pens in a 3 × 2 factorial design in two adjacent rooms with controlled temperature. The study had three replicates consisting of 39 chickens per room, 13 per ecotype per pen making a total of 234 chickens. In one room, temperature was maintained at 26.5 ± 0.5 °C while in another it was maintained at 32±1 °C for 7 days and thereafter 37±1 °C for 10 days. A similar design was used in experiment two except that chickens were fed 55% less energy. In experiment one, serum corticosterone levels increased (p<0.05) in C and K. Gene expressions for hsp70 and iNOS were unchanged though hsp70 levels for K were higher (p<0.05). In experiment two, corticosterone levels were significantly elevated (p<0.05) in all ecotypes. Heterophil/lymphocyte ratios were markedly increased and changes in Hb and Hct at higher temperatures showed ecotype differences. Serum triglycerides were significantly reduced in all ecotypes. Hsp70 and iNOS levels were up-regulated in all ecotypes with levels in K higher (p<0.05) than in M. In both experiments, there were marked reductions in serum total protein. These results suggest that ecotype-based differences exist in local chickens’ responses to heat stress and its combination with low energy diets. M and C demonstrated better tolerance than K when only heat stress was applied but a synergistic effect of heat stress and low dietary energy suggested M is more tolerant.

Estimation of Genetic Parameters for Body Weight and Some Colour Traits in the Seventh-generation Index Selected Nigeria Heavy Local Chicken Ecotype

Background: This study was conducted to estimate the genetic parameters of body weight and some colour traits in seventh generation (G7) index selected Nigerian Heavy Local Chicken Ecotype (NHLCE) progenies at point of lay to 12 weeks. Methods: 5 sires and 12 hens were used to generate the progenies used for the experiment. Traits measured included weekly body weight, egg colour, beak colour and feather colour. Data collected were subjected to one way analysis of variance in a Paternal half sib analysis using Animal model of SAS (2003). Four weeks body weight measurements, egg colour, beak colour and feather colour for 5 sires ranged from 1.29±0.05 1.54±0.07; 2.55±0.02 to 4.00±0.02; 2.45±0.02 to 4.83±0.02 and 1.73±0.02 to 4.58±0.04 respectively. Result: The new Duncan’s multiple range test shows that sire families are similar (p greater than 0.05) in the body weight and beak colour, but significantly differed (p greater than 0.05) in the egg colour and feather colour. The heritability estimates of mature body weight for week 3 was medium, while estimates of heritability for weekly mature body weight for weeks 1, 2 and 4, egg colour, beak colour and feather colour of NHLCE were low heritability. Low h2 of traits suggest that progeny and pedigree selection could be employed for improvement of the egg colour, beak colour and feather colour of NHLCE. The study showed positive genetic correlations between beak colour and egg colour, negative genetic correlations between beak and feather colour. This means that no decision can be taken in isolation as the selection of one trait will have consequences on other traits.

A genome-wide scan to identify signatures of selection in two Iranian indigenous chicken ecotypes

BackgroundVarious regions of the chicken genome have been under natural and artificial selection for thousands of years. The substantial diversity that exits among chickens from different geographic regions provides an excellent opportunity to investigate the genomic regions under selection which, in turn, will increase our knowledge about the mechanisms that underlie chicken diversity and adaptation. Several statistics have been developed to detect genomic regions that are under selection. In this study, we applied approaches based on differences in allele or haplotype frequencies (FST and hapFLK, respectively) between populations, differences in long stretches of consecutive homozygous sequences (ROH), and differences in allele frequencies within populations (composite likelihood ratio (CLR)) to identify inter- and intra-populations traces of selection in two Iranian indigenous chicken ecotypes, the Lari fighting chicken and the Khazak or creeper (short-leg) chicken.ResultsUsing whole-genome resequencing data of 32 individuals from the two chicken ecotypes, approximately 11.9 million single nucleotide polymorphisms (SNPs) were detected and used in genomic analyses after quality processing. Examination of the distribution of ROH in the two populations indicated short to long ROH, ranging from 0.3 to 5.4 Mb. We found 90 genes that were detected by at least two of the four applied methods. Gene annotation of the detected putative regions under selection revealed candidate genes associated with growth (DCN, MEOX2 and CACNB1), reproduction (ESR1 and CALCR), disease resistance (S1PR1, ALPK1 and MHC-B), behavior pattern (AGMO, GNAO1 and PSEN1), and morphological traits (IHH and NHEJ1).ConclusionsOur findings show that these two phenotypically different indigenous chicken populations have been under selection for reproduction, immune, behavioral, and morphology traits. The results illustrate that selection can play an important role in shaping signatures of differentiation across the genomic landscape of two chicken populations.