effect OF BIOCHEMICAL POLYMORPHISMS ON performance TRAITS IN INDIGENOUS CHICKEN GENOTYPES
EFFECT OF BIOCHEMICAL POLYMORPHISMS ON PERFORMANCE TRAITS IN INDIGENOUS CHICKEN GENOTYPES
This study examined the impact of biochemical polymorphisms on chicken genotype performance parameters in Nigeria. The chickens were created through pedigree mating of Normal feathered, Frizzle feathered, and Naked Neck cocks to Normal feathered, Frizzle feathered, and Naked Neck hens, producing F1 progeny.
A total of 155 chicks, including 37 Frizzle, 79 Normal, and 39 Naked Neck chicks, had their body weight (g), breast girth (cm), and tibia length (cm) measured.
Each chicken's wing vein was scraped for 5 ml of blood at the 20-week mark, and the tubes were heparinized and labelled with its tag number for electrophoresis.
According to the mobility of transferrin, haemoglobin, and carbonic anhydrase on the cellulose-acetate paper, each bird was given one of three scores: quick (AA), halfway (AB), or slow (BB). The collected data were treated to the SAS, 2002, general linear model approach, and significant means were separated using the Tukey honestly significant difference test.
The genotypic and allelic frequencies were calculated using Hardy Weinberg's equation and evaluated using chi-square (2). Each of the three biochemical markers was separated into AA, AB, and BB, three polymorphic variants.
From day one to eight weeks, the Frizzle feathered weighed significantly more (338.54g) than both the Normal feathered (319.59g) and Naked Neck (295.51g), but from twelve to twenty weeks there were no significant differences (P>0.05) and there was no discernible pattern for the length of the tibia or the circumference of the breast.
men had considerably greater body weight (1168.79g) than females (937.06g), significantly larger breasts (25.74cm) than females (24.24cm), and significantly longer tibias (9.59cm) than females (8.96cm) than men (P0.05).
Transferrin (TfAA, TfAB, and TfBB) had genotypic frequencies of 8, 140, and 7 respectively; haemgolobin (HbAA, HbAB, and HbBB) had genotypic frequencies of 49, 56, and 50; and carbonic anhydrase (CaAA, CaAB, and CaBB) had genotypic frequencies of 63, 79, and 13 respectively.
The polymorphic forms' effects on body weight (g), breast girth (cm), and tibia length (cm) revealed that the AA had significantly greater body weight (g) than the AB and BB for transferrin (1434.75g, 1047.11g, and 1047.43g, respectively) and haemoglobin (1296.43g, 1029.59g, and 884.46g, respectively) than the AB and BB.
In the cases of transferrin and haemoglobin, the AA was likewise greater (P 0.05) than the AB and BB for breast girth (cm) and tibia length (cm). Body weight (g), breast girth (cm), and tibia length (cm) exhibited no consistently significant changes (P>0.05) in the carbonic anhydrase across the various genotypes. Conclusion:
The genotypes for Frizzle feather may have body weights acceptable for meat production. The result of sexual dimorphism demonstrated that sex had an impact on the parameters. The high level of heterozygosity suggests that more heterozygotes have evolved and fared better than homozygotes in terms of adaptation and survival.
The impact of the biochemical markers' polymorphic forms on body weight (g), breast circumference (cm), and tibia length (cm) revealed that transferrin and haemoglobin may be used to choose body weight, however carbonic anhydrase might not be the best option.
The native chicken breeds, also known as indigenous chickens, are genetically suited to harsh environments with scarce resources and significant threats from predators, infections, and climatic conditions (Mwacharo et al., 2005; Sorenson, 2009).
They frequently serve multiple functions at once (Sorenson, 2009; Adeleke et al., 2011a), and they also have distinctive characteristics that are valuable local adaptations compared to commercial breeds (which have been selected for a particular set of performance traits).
Some local hens have unique qualities that could be appealing to commercial breeders. As a result, native chickens may serve as a genetic resource for future breeding plans (Horst, 1999).
When the same genes produce various proteins or, more specifically, different amino acids in different people, strains, or breeds, this phenomenon is known as genetic or protein polymorphism (Rege and Okeyo, 2006; Kwaga, 2006).
According to Das and Deb (2008), this occurs when two or more discontinuous protein forms are present in a species or population in such a quantity that the rarest phenotype, which has a frequency of more than 0.1 percent, cannot be preserved alone through recurrent mutation.
According to Akpa et al. (2011), protein polymorphism can be used to map (locate) genes that cause diseases, choose superior animals for breeding, and help match two samples of deoxyribonucleic acid (DNA) to determine if they originate from the same source.
Generally speaking, this variation in proteins can be applied to the study of genetic diversity within a population's gene pool by using two approaches, namely protein electrophoresis and protein 2 immunology,
while keeping in mind that the fundamental idea behind the mobility across gels in electrophoresis of enzymes and other proteins denotes differences in allelic groups responsible for variations in amino acids in the protein (Rege and Okeyo, 2006).
Transferrin is a polymorphic blood protein that may be detected in animal milk and serum (Steppa et al., 2009). It is also a key component of the egg white gene and is synthesised at high quantities in egg-laying birds (Lee et al., 1980).
Among all polymorphic blood proteins, transferrin has the largest heterogeneity (Steppa et al., 2009). Three different types of alleles, TfA, TfB, and TfC, were discovered in chicken on the gel electrophoresis separation, according to Das and Deb (2008).
In terms of egg production, hens with type “TfB” are superior to chickens with type “TfA.” The fertility, hatchability, and egg production (at least 90 days of production) appear to be significantly affected by heterozygous transferrin (TfBC), and chickens with TfA have delayed sexual maturity whereas chickens with TfB have an earlier age at sexual maturity.
According to Das and Deb (2008), haemoglobin is a polymorphic protein, conjugated globins-prosthetic group, and an erythrocyte pigment. It assists in the maintenance of a healthy blood response and transports carbon dioxide and oxygen (Das and Deb, 2008; Steppa et al., 2009).
According to Das and Deb (2008), the genotypic frequencies of the three haemoglobin polymorphic forms were 0.96: 0.04 for White Leghorn, 1.00: 0.00 for local chicken, 1.00: 0.00 for Guinea fowl, and 0.85: 0.15 for Japanese quail.
These three forms were regulated by the two autosomal alleles A1 and A2. According to Das and Deb (2008), haemoglobin polymorphism influences the chicken's rate of growth,
ability to hatch, and susceptibility to Marek's illness. However, Steppa et al. (2009) revealed that two codominant autosomal alleles were discovered in the sheep beta-haemoglobin chain.
Although carbonic anhydrase was not directly linked to chicken weight, it was found to have an impact on how haemoglobin was transported and used by hens (Das and Deb, 2008),
and haemoglobin is known to influence chicken development rate. Therefore, the carbonic anhydrase's impact on haemoglobin may also have an indirect impact on the pace of chicken growth.
Since the middle of the 1960s, the discipline of molecular biology, particularly the use of molecular markers to research genetic variety, has developed extremely quickly in order to evaluate genetic variation within and between breeds/strains.
In the late 1970s, DNA analysis, primarily through the use of restriction enzymes, replaced the predominance of protein electrophoretic approaches to population genetics and evolutionary biology. In the 1980s, mitochondrial DNA analyses and DNA fingerprinting approaches took their place (Rege and Okeyo, 2006).
The development of PCR-mediated (polymerase chain reaction-mediated) DNA genotyping and sequencing in more recent years has made it possible to access the most comprehensive genetic data quickly and easily (Miao et al., 2013).
Although DNA-based technologies are currently the preferred approaches, it would be incorrect to assume that DNA markers offer the best possible solution.
Because of their versatility, affordability, ease of use, availability to large amounts of genetic information, and ease of data interpretation, a number of alternative assays, such as protein/allozyme polymorphisms (biochemical), continue to be extremely helpful, particularly in developing nations (Rege and Okeyo, 2006).
Until now, characterization of quantitative traits in livestock, particularly in Nigeria, has primarily relied on phenotype or on estimated breeding values (EBV) derived from four phenotype,
without proper knowledge of how many genes are actually playing an effective role on the trait or knowing the specific effect of the individual genes. As a result, the genetic basis of traits is typically treated as a “hidden actor” (Naqvi, 2007).
Transferrin is a polymorphic protein that can be found in the blood serum, plasma, and eggs of poultry (Frelinger, 1972; Jaayid et al., 2011). Since sexual maturity is a function of an animal's growth, it has implications for evaluating performance in terms of weight gain.
On the other side, haemoglobin polymorphism has been explicitly connected to alter chicken growth and hatchability. The disparities in the performances of the birds are thought to be caused by their polymorphic haemoglobin and transferrin, which might be used for testing and selection to enhance genetic performance (Das and Deb, 2008).
While some members of the carbonic anhydrase gene family have been proposed to encourage cell proliferation and function as trophic/growth factors, carbonic anhydrase engage in the regulation of ion, water, and acid-base balance (Karhuma, 2002).
Therefore, the individual animal as well as the population as a whole might be genetically well characterised in relation to their performance by using various biochemical – genetic markers including transferrin, haemoglobin, and carbonic anhydrase (Jaayid et al., 2011).
Therefore, in order to understand the fundamental genetic processes that contribute to the variations in weight in the performance of local Nigerian chicken genotypes,
as well as the fact that there is a dearth of research of this kind in the nation, this study was carried out to examine the effect of biochemical polymorphisms on performance traits in indigenous chicken genotypes.
The purpose of this study was to explore the following alternative and null hypotheses:
H0: In Nigerian local chickens with normal, frizzled, and naked neck feathering, the biochemical polymorphic forms of transferrin, haemoglobin, and carbonic anhydrase had no impact on performance attributes.
HA: In Nigerian local chickens of Normal feathered, Frizzle feathered, and Naked Neck, the biochemical polymorphic forms of transferrin, haemoglobin, and carbonic anhydrase have an impact on performance attributes.
The following issues were to be addressed by this study:
i. To investigate the weight variations among and within the local Nigerian chicken varieties with normal, frizzle, and naked neck feathers.
ii. Calculating the genotypic and allelic frequencies of transferrin, haemoglobin, and/or carbonic anhydrase within and between genetic groups.
iii. To ascertain the impact of polymorphic transferrin, haemoglobin, and carbonic anhydrase on the growth performance of native Nigerian chickens with normal, frizzled, and naked neck feathers.