Incidence of udder abnormalities in West African Dwarf and Kalahari red goats: influence of teat number on milk production
A total of 646 goats comprising 580 West African Dwarf (WAD) sampled across Abeokuta South, Abeokuta North and Odeda Local Government Areas of Ogun State and 66 Kalahari Red (KR) goats from the Institute of Food Security, Environmental Resources and Agricultural Research (IFSERAR), Federal University of Agriculture, Abeokuta (FUNAAB), Nigeria were utilized for this study. The udder was appraised for shape, attachment, symmetry, teat number, teat shape and teat placement. Notable for udder abnormalities in the two breeds were asymmetrical udder, pendulous udder and supernumerary teats in varying frequencies. Frequencies of udder abnormalities in KR goats were asymmetrical udder (10.6%), pendulous udder (1.5%) and supernumerary teats with variations from three teats (15.2%), to four teats (57.6%) and five teats (9.1%). Percentage individuals with symmetrical udder and normal two teats were 87.4% and 18.2% respectively. Udder shapes were bowl (9.1%) and cylindrical (86.4%). Udder shapes could not be determined (undifferentiated) in 4.5% of the KR does. Teat shapes were cylindrical (39.4%) and funnel (60.6%) while teat placements were oblique (65.2%) and vertical (34.8%). In WAD goats, 6.4% and 0.3% had asymmetrical and pendulous udders correspondingly while majority (93.3%) of does had symmetrical udder. Percentage individuals with two teats, three teats, four teats and five teats were 72.8%, 16.2%, 9.5% and 1.6% respectively. Udder shapes were bowl (56.7%), cylindrical (34.0%) and round (0.3%) while 9.0% were in the indifferent stage. Teat shapes were cylindrical (64.0%) and funnel (36.0%) while teat placements were oblique (71.7%) and vertical (28.3%). The study revealed a preponderance of four teats (58.82%) in KR goat compared with the normal two-teat condition prevalent in WAD goat. A high proportion of the supernumerary teats in KR were functional while rudimentary teats in WAD were non-functional. Daily milk offtake and yield were not significantly (P>0.05) influenced by teat number in both breeds. Variations in teat number may be useful in setting breed standard for both populations. A study on inheritance of supernumerary teats recommended.
Keywords: Goat, udder characteristics, milk offtake, milk yield