DOES INCREASING LEVEL OF CONDENSED DISTILLERS SOLUBLES (PROTIWANZE®) SUPPLEMENTATION AFFECT MILK PRODUCTION IN DAIRY CATTLE ?

INTRODUCTION
The objective of this study was to evaluate whether introducing the condensed distillers solubles Protiwanze® (PW) at different concentrations in dairy cows diet induces changes in milk production.
MATERIAL AND METHODS
Three herds (72 Holstein and 25 Brown Swiss, DIM = 101 ± 57; daily milk production = 34.90 ± 8.40 L) received successively two RTM differing in PW content for 4 weeks, including a 7-day transition: 0% and 10% on a dry matter basis for Herd 1 and 10% and 15% for Herd 2 and 3. Both concentrations were distributed alternatively and repeated twice, each cow being its own control. Rations were formulated to meet energy and nitrogen requirements. During each testing period, animals were scored (Body Condition, Rumen Fill, Fecal Consistency, Undigested Fraction according to Zaaier (2001)) and their milk production and composition were measured by the Dairy Herd Improvement.
RESULTS AND CONCLUSION
Increasing the level of PW did not significantly change milk production in any Herd: Values were for Herd 1 at PW0%: 33.08 ± 0.76 L, at 10%: 31.66 ± 0.68 L, for Herd 2 at PW10%: 32.85 ± 0.93 L and at 15%: 32.37 ± 0.89, for Herd 3 at PW10%: 28.71 ± 1.21 L and at 15%: 31.80 ± 1.16. In Herd 1, milk urea decreased from 243.80 ± 4.55 mg/L for PW0% to 218.05 ± 4.03 mg/L for PW10%, (p<0.01), while fat percentage increased from 3.38% ± 0.09 (PW0%) to 3.77% ± 0.08 (PW10%) (p<0.01). Concerning scores, unconclusive changes were observed.
Although increasing level of PW in dairy cows diet did not change milk production or composition, it is profitable since PW is 30-40% cheaper than other protein supplements like soya and canola meals.
Moreover, it allowed to lower milk cost price by 1,5 eurocent per liter, when used at higher concentration.