Date of Award

Winter 2017

Project Type


Program or Major

Biological Sciences

Degree Name

Master of Science

First Advisor

Peter S Erickson

Second Advisor

Andre F Brito

Third Advisor

William E Berndtson


The objective of this study was to determine the effect of varying levels of sodium, butyrate (SB) on the growth, digestibility, and health of post-weaned heifers. Forty Holstein, dairy heifers with a mean age of 84 d and average body weight (BW) of 100.88 kg were housed, in a naturally ventilated freestall barn. Heifers were blocked by birth date and randomly assigned, to 1 of 4 treatments in a completely randomized block design: (1) 100 g of soybean meal carrier, (control; CON); (2) 0.25 g SB/kg of body weight + carrier (0.25SB); (3) 0.50 g SB/kg of BW +, carrier (0.50SB); (4) (0.75 g SB/kg of BW + carrier (0.75SB). Treatments were top-dressed and, hand-mixed into a total mixed ration (TMR) once daily. Heifers had free access to water. Initial, BW, hip and withers heights, heart girth and body length were measured before the start of the, study and every week thereafter until the 15 wk trial was over. Blood samples were obtained and, plasma urea nitrogen, glucose, and β-hydroxybutyrate (BHB) concentrations were determined, prior to the start of treatment and weekly after until the conclusion of the study. Fecal samples, were taken prior to treatment and every other week from each heifer for coccidia counts., Apparent total-tract nutrient digestibility was determined utilizing a chromium oxide marker., Each heifer underwent this phase at 47 d on study until 54 d on study. Sodium butyrate appeared, to increase the digestibility of acid detergent fiber (ADF) and organic matter (OM) (P = 0.08; P, = 0.07, respectively). Sodium butyrate had a positive effect on average BW and overall BW gain., Sodium butyrate had no performance effects on skeletal growth or blood metabolites. Average, daily gains were 1.16, 1.15, 1.17, and 1.24 kg/d (P = 0.12) and daily dry matter intakes (DMI), were 5.09, 4.84, 5.19, and 4.91 kg/d (P = 0.85) for CON, 0.25SB, 0.50SB, and 0.75SB,, respectively. There was a trend towards improved feed efficiency (FE). Fecal samples from each, heifer indicated the presence of coccidian, but the counts were variable within blocks and not, consistent across heifers within each pen. There was a trend towards positive feed efficiency., Sodium butyrate supplementation offers positive results in the growth performance and feed, efficiency of post-weaned heifers.