Perbandingan Morfometrik dan Karakteristik Genetik Eksternal pada Ayam IPB dan Ayam Kampung

Abstract

Ayam IPB D1 merupakan ayam lokal yang bertujuan meningkatkan keunggulan dari ayam kampung dengan hasil pengembangannya, yaitu IPB D2 berdasarkan ketahanan penyakit dan IPB D3 berdasarkan pertumbuhan bobot badan cepat. Penelitian ini bertujuan menentukan variabel pembeda melalui hasil analisis diskriminan Fisher antara ayam IPB D1, IPB D2, IPB D3 dan ayam kampung. Penentuan karakteristik genetik eksternal pada masing-masing ayam diperoleh pada penelitian ini, serta membentuk dendrogram berdasarkan jarak mahalanobis dan jarak genetik. Total data ayam yang digunakan dalam penelitian adalah 987 ekor (202 ekor IPB D1, 263 ekor IPB D2, 280 ekor IPB D3, dan 242 ekor kampung). Pengukuran permukaan tubuh linear yang digunakan adalah panjang femur (X1), panjang tibia (X2), panjang tarsometatarsus (X3), lingkar tarsometatarsus (X4), panjang jari ketiga (X5), panjang sayap (X6), panjang maxilla (X7), dan tinggi jengger (X8). Karakteristik genetik eksternal yang diamati adalah warna shank, bentuk jengger, dan warna bulu (colour distributing genes, uniform changing colour genes, colour restricting genes, dan pattern genes). Analisis data pengukuran permukaan tubuh linear adalah statistik deskriptif, statistik T2-Hotelling, diskriminan linear fisher, klasifikasi Wald-Anderson, dan jarak minimum D2-Mahalanobis. Analisis karakteristik genetik eksternal adalah penentuan distribusi data, frekuensi gen, heterosigositas, dan jarak genetik. Pembuatan dendrogram berdasarkan jarak minimum mahalanobis dan jarak genetik. Hasil penelitian menunjukkan bahwa ditemukan variabel pembeda antara ayam IPB D1 jantan vs ayam IPB D2 jantan (X4 dan X8), ayam IPB D1 jantan vs ayam IPB D3 jantan (X4), ayam IPB D1 betina vs ayam IPB D3 betina (X1 dan X4), ayam kampung jantan vs ayam IPB D1 jantan (X1, X4, X7, dan X8), ayam kampung betina vs ayam IPB D1 betina (X4 dan X5), ayam kampung jantan vs ayam IPB D2 jantan (X1), ayam kampung betina vs ayam IPB D2 betina (X8), ayam kampung jantan vs ayam IPB D3 jantan (X8), dan ayam kampung betina vs ayam IPB D3 betina (X1). Individu yang tidak sesuai klasifikasi Wald-Anderson sebaiknya disingkirkan untuk menyisakan ayam yang sesuai karakteristiknya. Perhitungan nilai heterosigositas untuk karakteristik genetik eksternal (warna shank, bentuk jengger, dan warna bulu) pada ayam IPB D1, ayam IPB D2, ayam IPB D3, dan ayam kampung menunjukkan tidak ada perbedaan atau serupa sehingga karakteristik genetik eksternal belum dapat ditentukan. Jarak minimum mahalanobis dan jarak genetik menunjukkan divergensi genetik antara ayam IPB D1, ayam IPB D2, ayam IPB D3, dan ayam kampung.

IPB D1 chicken is a local chicken that aims to enhance the advantages of native chicken. This development has resulted in two improved lines the IPB D2 known for its disease resistance and the IPB D3 characterized by rapid body weight gain. This study aims to determine the distinguishing variables through the results of Fisher discriminant analysis between IPB D1 chicken, IPB D2 chicken, IPB D3 chicken, and native chicken. The determination of external genetic characteristics in each chicken was obtained in this study, and dendrograms were formed based on mahalanobis distance and genetic distance. The total data used in the study was 987 chickens (202 IPB D1 chickens, 263 IPB D2 chickens, 280 IPB D3 chickens, and 242 native chickens). Linear body surface measurements used were femur length (X1), tibia length (X2), tarsometatarsus length (X3), tarsometatarsus circumference (X4), third finger length (X5), wing length (X6), maxilla length (X7), and comb height (X8). External genetic characteristics observed were shank colour, comb shape, and plumage colour (colour distributing genes, uniform changing colour genes, colour restricting genes, and pattern genes). The linear body surface measurement data analysis included descriptive statistics, T2-Hotelling statistics, fisher linear discriminant, Wald-Anderson classification, and D2-Mahalanobis minimum distance. The analysis of external genetic characteristics is the determination of data distribution, gene frequency, heterozygosity, and genetic distance. The construction of a dendrogram is based on the calculation of minimum mahalanobis distance and genetic distance. The results showed that distinguishing variables were found between IPB D1 roosters vs IPB D2 roosters (X4 and X8), IPB D1 roosters vs IPB D3 roosters (X4), IPB D1 hens vs IPB D3 hens (X1 and X4), native roosters vs IPB D1 roosters (X1, X4, X7, and X8), native hens vs IPB D1 hens (X4 and X5), native roosters vs IPB D2 roosters (X1), native hens vs IPB D2 hens (X8), native roosters vs IPB D3 roosters (X8), and native hens vs IPB D3 hens (X1). Chickens that do not conform to the Wald-Anderson classification should be culled to maintain a flock with the desired characteristics. Estimation of heterozygosity values for external genetic characteristics (shank color, comb shape, and plumage colour) in IPB D1 chickens, IPB D2 chickens, IPB D3 chickens, and native chickens showed no difference or similarity so that external genetic characteristics could not be determined. Minimum mahalanobis distance and genetic distance showed genetic divergence between IPB D1 chicken, IPB D2 chicken, IPB D3 chicken, and native chicken.