Comparing Chick and Grower Stages of Nine Breeds of Gallus gallus domesticus, Linnaeus, 1758 for RBC and WBC Parameters


 The present study estimates haematological parameters of different breeds of chicken, viz., Aseel, Black Rock, Dahlem Red, Kadaknath, Naked-neck, Red Cornish, Rhode Island Red, Vanaraja and White Leghorn. Blood samples were collected from 40 unsexed birds of each breed, comprising 20 chicks (< 2 months) and 20 growers (2-8months). Erythrocytic parameters such as Haemoglobin, Total Erythrocyte Count, Packed Cell Volume and erythrocyte indices and leukocytic parameters such as Total Leukocyte Count and Differential Leukocyte Count were taken into account. The data were subjected to ANOVA followed by post-hoc analysis and significant differences were observed at p < 0.01 and p < 0.05. As a whole, Red Blood Cell and White Blood Cell parameters (except Total Leukocyte Count and Basophil percentage which are not significantly different) record significant differences at p < 0.01 among and between the breeds. But some birds also differ at p < 0.05 among and between themselves.


Introduction
The investigation was conducted on nine breeds of chicken (Gallus gallus domesticus) maintained by local poultry farmers of Bhubaneswar as backyard poultry. These breeds are Aseel, Black Rock, Dahlem Red, Kadaknath, Naked-neck, Red Cornish, Rhode Island Red, Vanaraja and White Leghorn. Aseel (AS) means real or pure and native to Andhra Pradesh. The standard weight varies from 3 to 4 kg for cocks and 2 to 3 kg for hens. Sexual maturity is gained at 196 days and produces 92eggs per year. (Anonymous 2018). Black Rock (BR) chicken is a hybrid of selected strains of RIR cockerels and Barred Plymouth Rock hens. They are good foragers, densely feathered to protect from ailments and have strong immune system. They lay around 280 brown eggs in their rst year. Dahlem Red (DR) is a dual-purpose chicken. The DR males and females weighed 1786g and 1285g respectively at 20 weeks of age. Sexual maturity is attained at 218 days. Mean total egg production in 52 weeks is 143 (Horst 1999). Kadaknath (KN) or Kalamasi, a fowl with black esh has most of the internal organs intense black coloured. The blood is also darker than normal blood. These are due to deposition of melanin. Body weight is 920 g at 20 weeks and attains sexual maturity at 180 days of age and lays 105 light brown eggs per year (SA PPLPP 2009). Naked-neck (NN) or Transylvanian Naked-neck or Turken has a brilliant reddish plumage with bright red coloured featherless neck and vent. They are able to withstand very high temperature than other chicken. They are good layers and meat producers. The standard weights of cock, cockerel, hen and pullet are 3.82kg, 3.37 kg, 2.92 kg and 2.47 kg respectively and lays 180eggs per year (Grobbelaar et al. 2010). Red Cornish (RC) or Indian game bird are heavy, muscular birds and require little feed if allowed free range and produce 160-180 brown eggs per annum. However, they are highly prone to parasites and need extra shelter as their feathers tend to be thinner than other chicken . Rhode Island Red (RIR) is probably best egg-layer, laying 250 eggs per year among dual-purpose chickens and has been widely used for that function. It is advantageous over other breeds because of longevity and very strong adaptability to all sorts of conditions or feed . Vanaraja (VR) is a multi-coloured dual-purpose bird with attractive plumage, better immunity against common poultry diseases and adaptable to the free-range rearing. The males attain moderate body weight at eight weeks of age under regular feeding system. The hen lays 160-180 eggs in a laying cycle. (Anonymous 2007(Anonymous -2008 Kadaknath, one hybrid of chicken and domesticated turkey Naked-neck and one synthetic breed Vanaraja. All chicken breeds have common ancestor the Red Jungle Fowl (RJF) and the variety of breeds are the result of excessive breeding and cross-breeding programs. Due to which, though all these breeds are different but they all are placed in same taxonomic position and comes under same binomial name Gallus gallus domesticus (Kanginakudru et al., 2008).
In poultry birds, many factors in uence blood parameters, like molting (Driver 1981 for two minutes for later staining. Samples collected were kept in ice box and taken to laboratory for haematological analyses on the same day.

Description of methods and tools
Estimation of CBC include parameters like haemoglobin per cent (Hb %), total erythrocyte count (TEC), total leukocyte count (TLC), packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) and differential leukocyte count (DLC

Discussion
All the grower chicken from the present study has some or other similarity with that of 6-12 months old indigenous chicken from Bangladesh studied by Sharmin and Myenuddin (2004)  Maximum birds from the present study show monocytosis which may be due to some infections or in ammations. Present study re ects eosinophilia in all birds which may be due to in ammatory and allergic reactions in body caused by food, water or environment (Clark et al. 2009). H/L ratio, an indicator of stress level, is also enhanced except, NN and VR chicks. Normally, H/L ratio should be 0.4-0.5 but under stress it goes up. Also, the heterophil count is more than lymphocyte count (Bedáňová et al. 2007), except the above-mentioned birds. These conditions occur when the birds are under some kind of stress or suffering from any physiological or pathological conditions.
The current study reports that erythrocytic and leukocytic parameters change with respect to age and sex among and between nine breeds of chicken though all of them belong to same taxa and comes under same binomial name, Gallus gallus domesticus. The likeliness observed while comparing this work with previous publications might have resulted mostly due to closeness in age, breed, taxonomic position, climate, environment, onset of maturity in case of growers, time of collection of blood or similar farm conditions. Apart from these factors, similarity in erythrocyte indices such as MCH, MCV and MCHC and H/L ratio might have been observed because of following same formula as previous authors while calculating. The matching of observations with many control group birds from previous researches might have occurred because the birds considered in the present study are not subjected to any type of dietary or accommodative experiments. This study may focus on the effect of above parameters on the quality of chicken poultry products and may help future investigators to consider these factors during analysis and interpretation of data. Moreover, genetic studies can reveal where these birds differ from each other and their common ancestor red jungle fowl (RJF) due to which also, the differences in their blood parameters might have occurred.