Effect of sorghum grain processing and fat supplementation on performance and nutrient utilization in lactating dairy cows.

Persistent Link:
http://hdl.handle.net/10150/187255
Title:
Effect of sorghum grain processing and fat supplementation on performance and nutrient utilization in lactating dairy cows.
Author:
Simas, Jose Manuel Correia de.
Issue Date:
1995
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Three experiments were conducted to determine effects of fat supplementation and ruminal starch degradability on lactation performance, and nutrient digestibilities in lactating cows. Four cannulated cows were used in a 4 x 4 Latin square design to determine effects of fat supplementation and ruminal starch degradability on ruminal fermentation and nutrient flow to the duodenum. Treatments were: (1) dry-rolled sorghum (DRS), no added fat; (2) DRS plus 2.5% fat; (3) steam-flaked sorghum (SFS), no added fat; (4) SFS plus 2.5% fat. SFS resulted in higher total VFA, propionate and butyrate, and the lowest C2:C3 ratios compared to DRS when fat was not added to the diets. Diets with SFS had higher ruminal (73.4 vs. 52.1%) and total tract (99.1 vs 95.0%) starch digestibilities then those with DRS. Duodenal flows of total CP and microbial protein were not affected by diets. Fat supplementation increased milk production, ruminal propionate and total VFA concentration and decreased C2:C3 ratio in diets containing DRS. In another, study 40 cows alloted to five dietary treatments: (1) DRS, no added fat; (2) DRS plus 2.5% fat; (3) SFS no added fat; (4) SFS plus 2.5%; (5) SFS plus 5% fat. Milk yield was increased by SFS and fat supplementation (2.5% of DM), the effects being additive. Fat supplementation at 5% did not improve lactation performance but increased body weight gain. Milk composition was not affected by treatments; however, milk protein yield was increased by SFS. Digestibilities of starch were increased (98.2 vs. 92.6%) with SFS compared to DRS. In the third trial, 48 cows were used in a 2 x 3 factorial arrangement of treatments. Diets contained DRS or SFS with 2.5% of cottonseed oil, tallow, or prilled fatty acids. Compared to DRS, SFS did not affect milk production, but increased milk protein content, body weight gains and estimated NE$\sb{\rm L}$ (22.6%) of sorghum grain, regardless of fat source. Fat sources did not affect lactation response, however prilled fatty acids tended to decrease DMI. SFS increased DM, OM, CP, and starch digestibilities, regardless of fat source.
Type:
text; Dissertation-Reproduction (electronic)
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Animal Sciences; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Huber, J. T.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleEffect of sorghum grain processing and fat supplementation on performance and nutrient utilization in lactating dairy cows.en_US
dc.creatorSimas, Jose Manuel Correia de.en_US
dc.contributor.authorSimas, Jose Manuel Correia de.en_US
dc.date.issued1995en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThree experiments were conducted to determine effects of fat supplementation and ruminal starch degradability on lactation performance, and nutrient digestibilities in lactating cows. Four cannulated cows were used in a 4 x 4 Latin square design to determine effects of fat supplementation and ruminal starch degradability on ruminal fermentation and nutrient flow to the duodenum. Treatments were: (1) dry-rolled sorghum (DRS), no added fat; (2) DRS plus 2.5% fat; (3) steam-flaked sorghum (SFS), no added fat; (4) SFS plus 2.5% fat. SFS resulted in higher total VFA, propionate and butyrate, and the lowest C2:C3 ratios compared to DRS when fat was not added to the diets. Diets with SFS had higher ruminal (73.4 vs. 52.1%) and total tract (99.1 vs 95.0%) starch digestibilities then those with DRS. Duodenal flows of total CP and microbial protein were not affected by diets. Fat supplementation increased milk production, ruminal propionate and total VFA concentration and decreased C2:C3 ratio in diets containing DRS. In another, study 40 cows alloted to five dietary treatments: (1) DRS, no added fat; (2) DRS plus 2.5% fat; (3) SFS no added fat; (4) SFS plus 2.5%; (5) SFS plus 5% fat. Milk yield was increased by SFS and fat supplementation (2.5% of DM), the effects being additive. Fat supplementation at 5% did not improve lactation performance but increased body weight gain. Milk composition was not affected by treatments; however, milk protein yield was increased by SFS. Digestibilities of starch were increased (98.2 vs. 92.6%) with SFS compared to DRS. In the third trial, 48 cows were used in a 2 x 3 factorial arrangement of treatments. Diets contained DRS or SFS with 2.5% of cottonseed oil, tallow, or prilled fatty acids. Compared to DRS, SFS did not affect milk production, but increased milk protein content, body weight gains and estimated NE$\sb{\rm L}$ (22.6%) of sorghum grain, regardless of fat source. Fat sources did not affect lactation response, however prilled fatty acids tended to decrease DMI. SFS increased DM, OM, CP, and starch digestibilities, regardless of fat source.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineAnimal Sciencesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairHuber, J. T.en_US
dc.contributor.committeememberTheurer, C. Brenten_US
dc.contributor.committeememberRice, Richarden_US
dc.contributor.committeememberWise, M.en_US
dc.contributor.committeememberPrice, Ralphen_US
dc.identifier.proquest9603705en_US
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