In developing countries, sustainability in livestock farming requires monitoring of native domestic animal population which are well adapted to the local environment. Use of multivariate methods in analysing the morphometric traits to access the within and between population diversity will play a significant role in upkeeping of autochthonous genetic resources (Birteeb et al., 2014). Multivariate analyses of morphometric traits have been reported to be effective for a precise and objective discrimination of livestock species (Vohra et al. 2015; Mishra et al. 2017; Alhajeri et al. 2019; Silva-Jarquin et al. 2019; Bousbia et al. 2021).
Based on the BL, CG, HW, Malaimadu cattle can be categorised as small to medium sized animals. Similar type of short stature breeds of cattle reared close to the Western ghats of south India like Alamadi (Parameswari et al. 2021), Kasargod (Iype et al. 2016), Bargur (Ganapathi et al. 2013) and Pulikulam (Srinivasan and Sathiamoorthy 2020) were already registered as recognised indigenous breeds of India by National Bureau of Animal Genetic Resources (NBAGR), Karnal, Haryana, India.
High CV pertaining to horn parameters (HL, HCB, HCM, HCT, HDB, HDM, HDT) and FW may be due to the fact that selection was not applied or influenced more by the environmental factors for these traits, which was in concordance with Bousbia et al. (2021). Lesser variability in BL, CG, HW, FL and PG reveals that the Malaimadu cattle are of similar in their body size. This homogeneity might be due to natural selection favouring particular size and shape that is well adapted to local environment. Cluster analysis shows the first cluster was associated with variables related to horns and face, while the second cluster was formed by variables pertaining to bone growth providing insight into general body conformation of Malaimadu cattle. A paired t-test between selected linear traits indicates that the cattle is taller than longer and has a narrow face.
Traits like CG, BW, HCB, HCM and HDB were found to be strongly correlated with the other studied traits, whereas HDT was not correlated with most of the traits except HDB and HDM indicating the independence of this trait. Higher correlation of body weight with other morphometric traits indicates the fact that the development of various anatomical structures directly or indirectly influences the growth of the animal. The highest negative correlation between BL and FW indicates that increase in the length of the animal tends to have a narrow face, which supports the findings of paired t-test in the present study. Correlation among morphometric traits serve as the basis for employment of further multivariate techniques like PCA for distinguishing breeds of livestock (Yakubu et al. 2011).
The KMO measure of sampling adequacy computed across all variables was equal to 0.562 for Malaimadu cattle. Kaiser (1974) recommended that the variables with MSA above 0.50 could be proceded for factor analysis. However, Tolenkhomba et al. (2013) reported KMO-MSA as 0.60 in Manipur local cattle, Pundir et al. (2011) reported 0.89 in Kankrej cows and Verma et al. (2015) reported 0.75 in hilly cattle of Himachal Pradesh.
In this study, Varimax rotation method was applied to maximize the sum of the variances of the squared loadings. Six components with Eigenvalue greater than 1 were estimated and they cumulatively accounted for 70.19% of total variance. The remaining unexplained variation may be ascribing to the segregation of casual alleles at contributory loci, measurement error and environmental factors (Brooks et al. 2010). In accordance with the present study, Tolenkhomba et al. (2013) extracted six components which accounted for 69.77% of total variance in Manipur local cattle, whereas Pundir et al. (2011) and Verma et al. (2015) extracted three and five components accounted for 66.02% and 65.95% of total variance in Kankrej cows and hilly cattle of Himachal Pradesh respectively. The variables most closely associated with first component (CG, BW, HW and PG) tend to describe the general size and shape of the animal which was in agreement with Bousbia et al. (2021), Yakubu et al. (2009) and Carpenter et al. (1978).
The communalities after extraction of principal components gives the common variance that is shared between the variables (Yunusa et al. 2013). The lower and higher communality of TLS (0.289) and BL (0.823) indicates that these traits were less and more effective in explaining the total variation in body conformation of Malaimadu cattle compared to other traits.