Changes in udder morphology as a consequence of different milking frequency during first and second lactation in Canarian dairy goats

Abstract

We studied 52 goats, under two machine milking frequencies (x times daily): one (x1, n=28) or two (x2, n=24) times daily, during the Ist and the 2nd lactation, to observe the changes produced in udder morphology by the milking frequency. Measurements of udder (six traits) and teats (five traits), according to a modification of the Project FAO-M4, were recorded before morning milking approximately two months after parturition. The udders studied showed a marked intra-mammary groove and symmetry. Once-a-day milking increased dramatically the volume of the udder in both lactations. Milk yield explained only partially the differences in udder volume (0.06 to 0.27L/d). Udder depth, distance to floor and distance between teats were in correspondence with udder volumes. Mean floor distances varied from 21 to 23cm, in x1 milked goats and from 23 to 25cm in x2 milked goats. Furthermore, the udders of x1 milked goats showed bigger cisterns and higher teat angles. Teat length at constant diameter increased in x2 milked goats. Correlation coefficients were moderated and agreed with previous studies.