title: Reducing particle size of corn in lactation diets from 1,200 to 400 micrometers improves sow and litter performance.
abstract: One hundred primiparous sows were used to determine the effects of particle size of corn in lactation diets on sow and litter performance. The sows were fed a corn-soybean meal-based diet with the corn ground to 1,200, 900, 600, or 400 microns. Particle size of corn had no influence on sow BW or backfat loss (P > .30), subsequent weaning-to-estrus interval (P > .40), or percentage of sows returning to estrus (P > .09). However, ADFI was increased (linear effect, P < .04) as particle size was reduced from 1,200 to 400 microns. Pig survivability was not affected (P > .30) but litter BW gain was increased by 11% when sows were fed diets with 400 vs 1,200 microns corn (linear effect, P < .05). Apparent digestibilities of DM, N, and GE were increased by 5, 7, and 7%, respectively, as particle size was reduced from 1,200 to 400 microns (linear effects, P < .001). Intake of DE was increased 14% (13.7 to 15.6 Mcal/d) as corn particle size was reduced from 1,200 to 400 microns. Intakes of digestible DM and N also were increased (11 and 14%, respectively), whereas fecal excretions of DM and N were decreased by 21 and 31%, respectively (linear effects, P < .001). Reducing particle size increased severity of ulceration and keratinization (nonzero correlations of P < .04 and P < .004, respectively) in the esophageal region of the stomach, although the changes were not associated with reduced sow performance.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Animal Sciences and Industry, Kansas State University, Manhattan 66506-0201, USA.
authors.forename: K J
authors.initials: KJ
authors.lastname: Wondra
authors.forename: J D
authors.initials: JD
authors.lastname: Hancock
authors.forename: G A
authors.initials: GA
authors.lastname: Kennedy
authors.forename: R H
authors.initials: RH
authors.lastname: Hines
authors.forename: K C
authors.initials: KC
authors.lastname: Behnke
mesh_terms: D000821:Animal Feed / Q000592:standards; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D000833:Animals, Suckling / Q000254:growth & development* / Q000502:physiology; D004032:Diet / Q000662:veterinary*; D004063:Digestion / Q000187:drug effects / Q000502:physiology; D005243:Feces / Q000737:chemistry; D005260:Female; D007774:Lactation / Q000502:physiology*; D008098:Litter Size / Q000187:drug effects / Q000502:physiology; D010316:Particle Size; D011897:Random Allocation; D013270:Stomach / Q000033:anatomy & histology / Q000187:drug effects; D013552:Swine / Q000254:growth & development* / Q000378:metabolism; D003313:Zea mays / Q000592:standards*