Effects of Aspergillus oryzae on milk production, feed utilization and rumen fermentation in lactating dairy cows.

Persistent Link:
http://hdl.handle.net/10150/184589
Title:
Effects of Aspergillus oryzae on milk production, feed utilization and rumen fermentation in lactating dairy cows.
Author:
Gomez-Alarcon, Rogelio Alfonso.
Issue Date:
1988
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:
Two production trials were conducted for 84 d each. The first with 22 Holstein cows in late lactation. The second with 46 Holstein cows in early lactation. Treatments were C (control) and AO (A. oryzae 3g/d). Diets were for production trial 1 a 1:1 forage: concentrate ratio; for trial 2 was 2:3. Milk production in trial 1 was higher (P > .05) in AO fed cows during the first weeks of the trial. In trial two AO cows consistently produced more milk (P < .03). Rectal temperatures during hot weather (over 35°C) were consistently lower in AO fed cows, though not significant (P > .10). Two digestibility trials followed the production trials. For all digestion trials, Cr₂O₃ was used as digesta marker. In trial one AO tended to increase digestibility of DM (P > .10). In trial two digestibilities of DM, NDF and ADF were higher in AO fed cows (P < .05). Three other trials were conducted with mature Holstein cows fitted with ruminal and duodenal cannulae. The first trial tested two levels of forage (1:2 vs 2:1; forage to concentrate) and C vs AO in a 4x4 latin square design. AO increased (P < .05) ADF digestibility in the high concentrate died. No change (P > .10) in rumen pH, concentrations and proportions of VFA, and ammonia concentrations resulted from AO treatments. In the second trial C, AO and SC (Saccharomyces cerevesiae 3 g/d) were compared in a repeated 3x3 latin square design. A 1:2 forage to concentrate diet was fed to six lactating cows. Both AO and SC increased (P < .05) rumen NDF digestibility. The third trial compared C vs AO in a swithchback design with four lactating cows fed a 2:3 forage to concentrate diet. AO increased (P < .05) rumen fiber digestion. AO did not affect rates of passage of corn or alfalfa hay; or the potentially digestible DM of milo, alfalfa hay or wheat straw. AO did increase (P < .05) digestion rate of alfalfa DM. In vitro AO increased DM digestibility. That effect can be reproduced by incorporation of the additive at the time of inoculation.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Holstein-Friesian cattle.; Dairy cattle -- Feeding and feeds.; Milk yield.; Dairy farming.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Nutritional Sciences; Graduate College
Degree Grantor:
University of Arizona

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleEffects of Aspergillus oryzae on milk production, feed utilization and rumen fermentation in lactating dairy cows.en_US
dc.creatorGomez-Alarcon, Rogelio Alfonso.en_US
dc.contributor.authorGomez-Alarcon, Rogelio Alfonso.en_US
dc.date.issued1988en_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.abstractTwo production trials were conducted for 84 d each. The first with 22 Holstein cows in late lactation. The second with 46 Holstein cows in early lactation. Treatments were C (control) and AO (A. oryzae 3g/d). Diets were for production trial 1 a 1:1 forage: concentrate ratio; for trial 2 was 2:3. Milk production in trial 1 was higher (P > .05) in AO fed cows during the first weeks of the trial. In trial two AO cows consistently produced more milk (P < .03). Rectal temperatures during hot weather (over 35°C) were consistently lower in AO fed cows, though not significant (P > .10). Two digestibility trials followed the production trials. For all digestion trials, Cr₂O₃ was used as digesta marker. In trial one AO tended to increase digestibility of DM (P > .10). In trial two digestibilities of DM, NDF and ADF were higher in AO fed cows (P < .05). Three other trials were conducted with mature Holstein cows fitted with ruminal and duodenal cannulae. The first trial tested two levels of forage (1:2 vs 2:1; forage to concentrate) and C vs AO in a 4x4 latin square design. AO increased (P < .05) ADF digestibility in the high concentrate died. No change (P > .10) in rumen pH, concentrations and proportions of VFA, and ammonia concentrations resulted from AO treatments. In the second trial C, AO and SC (Saccharomyces cerevesiae 3 g/d) were compared in a repeated 3x3 latin square design. A 1:2 forage to concentrate diet was fed to six lactating cows. Both AO and SC increased (P < .05) rumen NDF digestibility. The third trial compared C vs AO in a swithchback design with four lactating cows fed a 2:3 forage to concentrate diet. AO increased (P < .05) rumen fiber digestion. AO did not affect rates of passage of corn or alfalfa hay; or the potentially digestible DM of milo, alfalfa hay or wheat straw. AO did increase (P < .05) digestion rate of alfalfa DM. In vitro AO increased DM digestibility. That effect can be reproduced by incorporation of the additive at the time of inoculation.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectHolstein-Friesian cattle.en_US
dc.subjectDairy cattle -- Feeding and feeds.en_US
dc.subjectMilk yield.en_US
dc.subjectDairy farming.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineNutritional Sciencesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.committeememberBrownen_US
dc.contributor.committeememberLeien_US
dc.contributor.committeememberReiden_US
dc.contributor.committeememberTheureren_US
dc.identifier.proquest8907401en_US
dc.identifier.oclc701901608en_US
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