Effects of strain x sex interaction on carcass traits and meat quality of three strains of commercial meat-type chicken

A total number of 288 day-old broilers of Arbor Acre, Hubbard and Marshal were randomly allocated to four treatments of 96 chicks each, with each treatment having three replicates of 8 birds comprising the sexes each with the aim of ranking the commercial meat-type strains as well as their sexes based on their carcass evaluation at 56 days of age. The traits considered were live weight, dressed weight, slaughter weight, eviscerated weight, breast weight, back weight, thigh + drumstick, wing weight, head and neck. Other traits measured were intestine, proventriculus + gizzard, liver and heart. Parameters on sensory values evaluated were Aroma, colour, flavor, tenderness, juiciness, texture, saltiness and overall acceptance. The obtained results indicated significant (P<0.01) effect of sex on the carcass parameters. Male broilers recorded higher mean values (2558.33g) of live weight, slaughter weight, dressed weight and other carcass traits than its female counterpart. Also, there was significant (P<0.01) effect of strain x sex interaction on live weight and slaughter weight. Males of Arbor Acre had the highest mean value (2650 g) of live weight, while the females of all the strains recorded lower values. In addition, there was no significant (P>0.05) effect of sex on Aroma and flavor at 8 weeks, while other sensory values recorded favored male birds of all strains. The obtained results indicated that most carcass traits are strain and sex dependent. Also, the results revealed that males of Arbor Acre and Hubbard strains gave greater chicken proportions than Marshall Broiler. Therefore, males of Arbor Acre and Hubbard broiler strains could be raised for maximum profit and increase animal proteins consumption. Keywords: Trait, strain, interaction, effect and se

Evaluation of genetic similarity and distance among seven Clariid fish populations in Kano Rivers, Nigeria

A population can only acquire new gene either through the immigration of individuals from surrounding populations. One of the greatest  advantages of microsatellite marker is that DNA sequence information is needed to perform the assay. Thus, a study was carried out to evaluate genetic similarity and distance in strains of Clariid species (Clarias gariepinus and Heterobranchus longifilis). In achieving this, 25 blood samples were gotten from Clarias gariepinus and 10 from Heterobranchus longifilis for DNA extraction. DNA were extracted, amplified and scored using  seven microsatellite markers. The markers were Cga01, Cga02, Cga03, Cga05, Cga06, Cga09 and Cga10. The gel images were then subjected to  molecular analysis using Genealex software to determine their base pairs and evaluate their genetic variability. The populations examined were Clarias gariepinus of River Dudusingaya (CgD), Ghari (CgG), Thomas (CgT), Karaye (CgK), Bagwai (CgB); and Heterobranchus longifilis of River Bagwai (HlB) and Ghari (HlG). Among the populations sampled, the genetic similarity ranged from 0.018 for CgD and CgT populations to 0.079 for CgT and HlG populations. The genetic distance observed in the populations ranged from 0.112 for CgG and CgB populations to 0.998 for CgT and CgK populations. The Clariid species that were closer indicated that the river locations shared tributaries and the Clariid species exchanged genetic materials over a long period of time. On the other hand, those that were farther apart indicated that they shared little or no tributaries. It can be concluded that the studied populations were not genetically pure but heterogeneous with varying degrees of genetic similarity and distance therefore, there were no. exhibition of genetic uniqueness and the populations were not isolated. Keywords: Genetic similarity, Genetic distance, Clariid population

Mathematical Modelling of Egg Production Curves of Shikabrown® Parents

This study was conducted to evaluate egg production curves of Shikabrown® parents, using mathematical models. A total of 200 birds: 100 from each of the two strains of Shikabrown® parents (sire and dam) lines at the Breeding Unit of Poultry Research Programme, National Animal Production Research Institute (NAPRI) were used for the study. The birds were obtained from the selected lines (sire and dam) and were denoted as Strain A and Strain B, respectively. Body weight (BWT), age at sexual maturity (ASM), egg number (EGGNO), and egg weight (EWT) were examined. Four non-linear models (Logistic, Richard, Gompertz, and Exponential) and a linear model were used to predict the efficiency of weekly bodyweight and egg production traits. The adequacies of the models were fitted using R Package, version 3.0.3. High coefficients of determination for BWT (R2 = 0.84 - 0.93) were recorded in the models for both Strains. Strain A had higher R2 (0.93) for BWT in Richard, Gompertz and Exponential models while Strain B recorded (R2 = 0.89) in Logistic, Richard and Gomprtz models. High coefficient of determination was obtained in a reproductive trait; egg number; in which almost all the models gave (R2 = 0.70). Exponential model recorded a higher R2 (0.93) for EGGNO in strain A. EWT in strain A recorded higher R2 (0.96) coefficient of determination across the four nonlinear models except linear model with (R2 = 0.95) for egg weight. Significant differences (P<0.05) were observed in the birds' performance for BWT and EWT, with strain B having a higher BWT (1.59±0.01) and Strain A having a higher EWT (48.75±0.17). Similarly, age of birds in lay had a concomitant significant differences (P<0.05) in their BWT as well as their EWT. The birds performed better for BWT and EWT in week 26 and 27 for both Strains. It was concluded that Strain significantly (P<0.05) had effect on BWT and EWT of Shikabrown® parent with Stain B performing better than Strain A in the former trait and strain A better than strain B in the latter trait. R2 identified differences between Strains in predicting egg production traits. Strain B was adjudged good and profitable because the Strain had the highest mean values in body weight and egg number and it is being recommended as one of the lines for future improvement of Shikabrown®. Keywords: Mathematical models, Egg Production Curves, Body weight, ASM, Egg Number, Egg weigh

In-silico amplification of randomly selected male - specific region – Y (MSY) genes as candidate genes for the selection of fertile indigenous bulls for artificial insemination

Molecular markers-based selection is a novel tool for unbundling complexities associated with the selection of animals for breeding improvement  programmes because these markers could contribute to full exploitation of animal potential prior to enrollment for improvement programmes. This study examined in-silico polymerase chain reaction amplification of some selected Male Specific region Y (MSY) genes in genome assemblies  including Bos_taurus_UMD_3.1.1/bosTau8 and ARS-UCD 1.2/bosTau9; BaylorBtau_4.6.1/bosTau7, Bos_taurus_UMD_3.1/bosTau6, and  Baylor4.0/bosTau4. The results of the amplification showed that 12 out of the selected 30 genes were expressed at an average primer melting temperature of 61.78 oC; while salt and annealing oligo concentrations were 50 mM and 50 nM per reaction, respectively. Out of expressed genes; 6, 5 and 1 genes were expressed in genome assemblies Bos_taurus_UMD_3.1.1/bosTau8, ARS-UCD1.2/bosTau9, and BaylorBtau_4.6. 1/bosTau7, respectively. The study concluded that the expressed genes are potential markers for selection of fertile bulls and the primers used are suitable for  in-vivo annotation of the genes in the prospective bull selection process for breeding programmes. Keywords: Male-specific region-Y genes (MSY); molecular markers; bulls and in-silic