Determining the relationships among milk urea nitrogen and milk production, milk protein, milk fat, and somatic cell counts from lactating dairy cows in Texas /
The objectives of this study were to determine the relationship between milk urea nitrogen (MUN) and milk production, milk protein, milk fat, and somatic cell counts (SCC) of lactating dairy cows and to determine the feed cost benefit of using best management practices (BMP) to reduce excessive nitr...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
2002.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=765073161&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | The objectives of this study were to determine the relationship between milk urea nitrogen (MUN) and milk production, milk protein, milk fat, and somatic cell counts (SCC) of lactating dairy cows and to determine the feed cost benefit of using best management practices (BMP) to reduce excessive nitrogen in the diet of dairy cows in Texas. The BMP were routine analysis of the formulated diet and MUN testing. Two feeding programs were evaluated, a total mixed ration (TMR) and grazing feeding systems. Within the grazing program, there were two breeds, Jersey and Holstein. The TMR program contained only Holsteins. Milk production, lactation number, herd effects, and test date were the variables used in the TMR model and the grazing herd model which impacted (P<.05), but did not strongly correlate (0.38 for the TMR model, and 0.51 for the grazing model) with the MUN concentration. Milk fat did not impact MUN concentration in the grazing herds (P=.64) or in the TMR fed herds(P=.84). No morning or evening milking variation of MUN concentrations was determined (P=.66), due to feeding periods being equally spaced throughout the day. The analysis of variance (ANOVA) model which included an average MUN concentration for morning and evening milking, date of test, and cow identification within herd resulted in a correlation coefficient of 0.78. The economic advantage of routine MUN testing and analyzing the reformulated diet was a $0.22 daily feed cost savings per cow. These BMP were an aid in reducing environmental loading of nitrogen. |
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| Item Description: | Vita. "Major Subject: Animal Science". |
| Physical Description: | xi, 65 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 59-64). |