Journal of Animal Research: v.5 n.1, p. 189-193. April. 2015

DOI Number: 10.5958/2277-940X.2015.00030.3

SHORT COMMUNICATION

Comparative Evaluation of Different Lactation Curve Models in Prediction of

Monthly Test-Day Milk Yields in Murrah Buffaloes

Manvendra Singh 1* , Avtar Singh 2 , Ashok Kumar Gupta 2 , Shakti Kant Dash 3 , Atul Gupta 4 , Saroj Kumar Sahoo 1 ,

Soumya Dash 1 and Pushp Raj Shivahre 1

1 Dairy Cattle Breeding Division, ICAR-National Dairy Research Institute Karnal, INDIA

2 Dairy Cattle Breeding Division, ICAR- National Dairy Research Institute, Karnal, INDIA

3 Animal Genetics and Breeding, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, INDIA

4 Animal Genetics and Breeding, Sardar Vallabh bhai Patel University of Agriculture & Technology, Meerut, INDIA

*Corresponding author: M Singh; Email: manav21vet@gmail.com

Received: 20 January, 2015

Accepted: 14 March, 2015

ABSTRACT

Present investigation was undertaken to compare the different lactation curve models for describing the shape of the lactation

curve in Murrah buffaloes. Data for the present study included 9071 monthly test-day milk yield (MTDMY) from 965 Murrah

buffaloes calved during 1977 to 2012 at the National Dairy Research Institute, Karnal. A total of 10 monthly test-day milk yield

records were taken at an interval of 30 days. The data were used to estimate lactation curve parameters for four lactation curve

models viz . Gamma type function (GF), Exponential function (EF), Mixed log function (MLF) and Polynomial regression

function (MLF). The mean monthly test day milk yields (MTDMY) increased from 5.91±0.13 kg on TD ₁ to a peak yield of

7.41±0.12 kg on TD _3. The estimates of coefficient of determination (R 2 ) and root mean square error (RMSE) for GF, EF, MLF,

and PRF were 96.42%, 98.65%, 98.48%, 99.86% and 0.077, 0.049, 0.052, 0.015, respectively. PRF fitted best to the test day

data followed by EF on the basis of higher R 2 and lower RMSE estimates, whereas GF fitted least .

Keywords: Comparative evaluation, Function , Lactation curve, Murrah, Monthly test-day

India is the largest milk producing country of the world

1923) or it can also be referred as the curve representing

with a production of 133 million tonnes of milk (BAHS,

the rate of milk secretion with advancement of lactation.

2013). Buffalo population of the country is 108.5 million

The aim of modelling the lactation curve is to predict milk

(Livestock Census, 2012) which contributes significantly

yield at any point of the lactation with minimum error.

(51.09 %) to the national milk production. Amongst

Many studies have been conducted in the past in dairy

various buffalo breeds found in India, Murrah is one of the

cattle and buffaloes using various lactation curve models

best and important breed with superior genetic potential for

to fit the lactation curve (Sahoo, 2014; Dongre, 2011 and

milk production. In buffaloes milk production trait follows

Banu, 2012). However, information is scanty on fitting

a curvilinear pattern over the complete lactation course.

of lactation curve models using test-day milk yields in

Understanding of the lactation curve of dairy animals

Murrah buffaloes. Therefore, the present investigation

provides an insight into the behavior of milk production

was undertaken to compare the different lactation curve

traits, which could be better used for augmenting wet

models for describing the shape of the lactation curve

and herd average. Lactation curve can be defined as the

in Murrah buffaloes and their efficiency in prediction of

graphical representation of milk yield against time (Brody,

monthly test-day milk yields.