Effects of Cottonseed Hulls Added to Diets With and Without Live Yeast or Mannanoligosaccharide in Young Calves

Hill, Stephanie Rene. The Effects of Cottonseed Hulls Added to Diets With and Without Live Yeast or Mannanoligosaccharide in Young Calves (Under the direction of Dr. B. A. Hopkins and Dr. L. W. Whitlow). The objective of this study was to investigate the effects of fiber in the form of cottonseed hulls (CSH) added to the starter and of live yeast (YST) or mannanoligosaccharide (MOS) added to milk, on growth, intake, rumen development, and health parameters in neonatal calves. Holstein (n = 116) and Jersey (n = 46) bull and heifer calves were assigned randomly at birth to one of six treatments. Calves continued on trial through 63 d. Bulls were castrated by 14 d. All calves were fed 3.8 L of colostrum daily for the first 2 d. Holstein calves were fed 3.8 L of whole milk and Jersey calves were fed 2.8 L of whole milk supplemented with either no additive, 4g YST, or 3g MOS daily through weaning at 42 d. Treatments included: 1) a corn/soybean meal based starter, 21% crude protein (CP), 6% acid detergent fiber (ADF), (CON), 2) a blend of 85% starter and 15% CSH, 18% CP, 15% ADF (CON + CSH), 3) starter and MOS (CON + MOS), 4) starter with CSH and MOS (CON + CSH + MOS), 5) starter and live yeast (CON + YST), and 6) starter with CSH and live yeast (CON + CSH + YST). Starter diets were offered from 1 d and daily amounts were increased by 0.09 kg when orts were 0 kg. Weekly measurements included body weight (BW), wither height, hip width, and dry matter intake from starter (DMI). Daily measurements included rectal temperatures, fecal, and respiratory scores. Twelve Holstein steers (2 per treatment) were killed for rumen tissue samples. Data were analyzed for the main effects of CSH, YST, and MOS. Average DMI was greater for Holstein calves consuming CSH diets (0.90 kg) than diets without CSH (0.75 kg). Body weight of Holstein calves on CSH treatments (54.9 kg) was greater (P<0 .05) than those fed diets without CSH (53.3 kg). Average daily gain was greater for Holsteins fed CSH diets (0.60 kg/d) than diets without CSH (0.54 kg/d). However, Holstein calves fed diets without CSH had a greater (P < 0.05) feed efficiency (0.65 kg feed/kg BW gain) than those fed CSH diets (0.71 kg feed/kg BW gain). There were no significant effects of YST or MOS on DMI, gain, or feed efficiency in Holstein calves (P >0.05). Holstein calves fed CSH diets had a lower (P < 0.03) fecal score (1.25) than those fed diets without CSH (1.34). Holstein calves fed CSH diets also had more narrow (P < 0.01) papillae (0.32 mm) compared to those fed diets without CSH (0.40 mm). There was no significant effect of additive on papillae length, width, or density. Surface area was not different across treatments or within sections of the rumen. Jersey calves fed YST or MOS had greater (P < 0 .03) final BW (51.2 kg and 51 kg) than calves fed no supplement (47.5 kg). There were no significant effects of CSH, YST, or MOS on DMI, WH, or HW in Jersey calves (P > 0.05). Jersey calves fed YST supplement had a lower (P < 0.05) fecal score (1.26) compared to Jersey calves fed NA (1.46). Cottonseed hulls did positively affect the growth and development of Holstein calves. This study indicates that cottonseed hulls are a suitable fiber source for calf starter rations and that YST or MOS may have beneficial effects on calf responses to stress during the post-weaning period. The Effects of Cottonseed Hulls Added to Diets With and Without Live Yeast or Mannanoligosaccharide in Young Calves by Stephanie Rene Hill A thesis submitted to the Graduate Faculty of North Carolina State University in partial fulfillment of the requirements for the Degree of Master of Science DEPARTMENT OF ANIMAL SCIENCE NUTRITION PROGRAM Raleigh 2003 APPROVED BY : ___________________ Dr. Gerald Huntington Member of the Advisory Committee _______________ ________________ Dr. Brinton Hopkins Dr. Lon Whitlow Co-Chair of the Advisory Co-Chair of the Advisory Committee Committee