Supreena Srisaikham, Naoki Isobe, and Wisitiporn Suksombat

DOI: 10.14456/sjst-psu.2018.39

pp. 278 - 289

Abstract

This research aimed to study the effects of supplementation at three levels of fresh cassava pulp (FCP) in the
concentrate diet of dairy cows: 1) 0 kg/d, 2) 3.5 kg/d (35 ppm hydrogen cyanide [HCN]), and 3) 7.0 kg/d (70 ppm HCN). The
effects studied were productive performance, milk yield, milk composition, and milk quality. Twenty-four Holstein Friesian
crossbred lactating dairy cows were blocked by lactation first and then stratified random balanced by days in milk, milk yields,
and body weight. Cows were assigned into randomized complete block design and divided into three groups of 8 cows each. All
cows were individually fed 21% crude protein concentrate together with ad libitum fresh grass and FCP according to the
supplemented treatments. The results showed that the total HCN content intake increased when the level of FCP supplementation
was increased. The supplementation of FCT at either 3.5 or 7.0 kg/d FCP had no negative effects on milk yield and milk
composition. Milk thiocyanate concentration, lactoperoxidase (LP) activity, and the keeping quality of milk were increased by
supplementation of FCP at 7.0 kg/d and decreased the somatic cell counts, standard plate counts, coliform counts, psychrotrophic
counts, and thermophilic counts. The present study suggested that supplementation of FCP at either 3.5 or 7.0 kg/d may be
associated primarily with increased efficiency of antibacterial activity of the LP system in raw milk thus improving the milk
keeping quality, In addition, the supplementation at either 3.5 or 7.0 kg/d of FCP possibly decreased the incidence of mastitis in
lactating dairy cows.