DIVERSITY IN MORPHOLOGY AND PIGMENTATION PATTERNS OF LOCAL PABNA CATTLE IN BANGLADESH

Indigenous cattle Phenotypic characterization Pigmentation Nucleus breeding The study was aimed to reveal the morphological features of local Pabna cattle at Bangladesh Livestock Research Institute (BLRI), Regional Station, Sirajganj and community levels. Data of various morphological features were collected from total 24 cattle from on-station and 8 cattle from community. It was observed that most of the morphological features were not varied between the studied cattle populations except body length, height at wither, pelvic length, tail dock circumference and mouth circumference (p <0.05). Pigmentation pattern revealed that light red was dominated for coat color in both cattle population while black color was most frequently observed in muzzle, eyelid, eyelash, horn, hoof, dew claw and tail switch. As most of the phenotypic observation and pigmentation patterns were unique between two existing Pabna cattle population, an open nucleus breeding system might be enhanced the desire dairy breed development from those cattle population regarding the uniformity of morphological features.


INTRODUCTION
Indigenous cattle population of Bangladesh are mainly indicus type encompassing various cattle genetic resources like Non-descript, Red Chittagong, Pabna, North Bengal Grey, Madaripur, and Munshiganj cattle.Genetic attributes of indigenous cattle are environmental adaptation and tolerance to drought, heat, diseases and ability to utilize low-quality local forages (Bhuiyan et al., 2007;Mwai et al., 2015).The non-descript cattle constitutes about 85-90% of the indigenous cattle population in our country.Pabna type cattle are considered as notable milch type cattle and famous for larger body size and better milk production among all the indigenous cattle populations, and also characterized by prominent hump and large dewlap (Hoque et al, 1999).This variety was developed at Shahjadpur of Sirajganj district by breeding with indigenous cows with Hariana and Sahiwal bulls in early 1900s (Bett et al., 2013).
Phenotypic characterization contributes to the improvement of animal genetic resources in the context of country-level implementation (FAO, 2012).Although several studies had been carried out for local Pabna cattle in Bangladesh (Husain et al., 1984;Husain andMostafa, 1985 andKhan et al., 1999), the in-depth information of phenotypic measurements and pigmentation patterns on Pabna cattle are scanty.Thus, this study was aimed to evaluate morphological characteristics of Pabna cattle at BLRI Regional Station, Sirajganj and also at farmers' community beside the river of Jamuna at Bera upazila of Pabna district in Bangladesh.

MATERIALS AND METHODS
Data of morphological measurements and pigmentation patterns of selected body parts were collected from 24 cattle (19 cows and 5 heifers) at BLRI Regional Station, Baghabari, Shahjadpur, Sirajganj using a pretested questionnaire including measuring tape and a recognized color chart (Aluminium Allied Centre, Kerala, India) for the white (01712), light red (02131), red (02412), black (03915) and the combination of red and black (reddish black or blackish red) colors during the period of August to September in 2017.The age of the purchased cows at BLRI regional station was between 31 months to 46 months of age (one or two permanent teeth) having at least one parity and milk production capability 5 to 6 liters per day.The heifers were between the age of 24 to 30 months showed at least one heat.The similar criteria were considered for data collection from 8 cows (35 to 40 months) of a community at Bera upazila of Pabna district during the measurement of morphometric features and pigmentation patterns.The gathered data were tabulated and analyzed following independent sample t test and one-way ANOVA with descriptive statistics using SPSS version 16 (SPSS Inc.Chicago, USA).

RESULTS AND DISCUSSION
The morphological characteristics of Pabna cattle (Figure 1) revealed that body length (p <0.01), height at wither (p <0.05), pelvic length (p <0.05), tail dock circumference (p <0.05) and mouth circumference (p <0.01) had significant variations between the cattle of BLRI Regional Station and farmer's community (Table 1).Most of the studied morphological traits related to body, head and udder characteristics (Table 1) were not varied statistically between cattle of BLRI Regional Station and farmer's community (p >0.05).However, the studied morphological features among the cattle of BLRI on-station were not varied statistically based on age differences (Table 2) except mouth circumference (p <0.01), and distance between fore and hind teats (p <0.05).Similar findings were observed in community except for body length (p <0.05) and rump length (p <0.05).The study of Udo et al. (1990) found similar findings on Pabna cattle for height at wither (118.21cm) and heart girth (147.56 cm) but much higher result for body length (164.39 cm) than the present observation for these cattle (112.42 cm).It might be the reason of difference between two measuring techniques.However, body length of Pabna cattle in this study was measured (shoulder point to pin bone) according to the instruction of phenotypic characterization of animal genetic resources (FAO, 2012).
The pigmentation frequency of different body parts showed that coat color of cattle had similarity for light red (79.17 and 62.50%) and red colors (20.83 and 37.50%) in both on-station and community, respectively (Figure 2).The same pattern observed for the color of reddish black (16.70%) in eyelid of the cattle at onstation than community.However, the color of muzzle, eyelid, eyelash, horn, hoof, dew claw and tail switch were almost unique for studied cows.Three types of colors identified for tail switch (Figure 3) in which black (62.50-79.20%)was dominated followed by reddish black (16.70-25%) and white (4.20-12.50%) in the studied cattle at on station and community.2007) reported that coat color of Pabna cattle varied within red or grey or the mixture of both which were agreed with our findings.However, our results indicating that the frequency of light red color was dominated in studied Pabna cattle population in both on-station and community levels while black color was dominated in muzzle, eyelid, eyelash, horn, hoof, dew claw and tail switch.Thus, selective breeding in the open nucleus breeding herd considering the observed dominated pigmentation patters in different body parts could established a breed having desire phenotypic features in the next generations.

CONCLUSION
It is concluded that most of the studied observations on morphological characteristics were similar for the existing Pabna cattle population of BLRI Regional Station and community.Thus, genetic improvement of those Pabna cattle having similar features might be enhanced following selective breeding through open nucleus breeding system to develop desire dairy breeds in Bangladesh.

Table 1 .
Morphological measurements of local Pabna cattle between on station and community

Table 2 .
Morphological measurements of local Pabna cattle within on-station and community based on age variation