UVM Theses and Dissertations
Format:
Print
Author:
Krawczel, Peter Downs
Dept./Program:
Animal Sciences
Year:
2011
Degree:
PhD
Abstract:
The welfare and productivity of dairy cows is dependent on their ability to satisfy behavioral needs on a daily basis. There is a growing body of evidence within the primary literature to support this, which has also lead to the development of various welfare auditing systems for dairy cows. Despite this increased awareness, there are multiple aspects of the relationship among these variables that have not been quantified. The objectives of this dissertation were designed to address some of these limitations.
The first study (Chapter 2) investigated the effect ofthree methods for experimentally increasing stocking density (denial ofaccess to feeding and resting space; denial of feeding, resting, and alley space; and the addition of cows) on the behavior, hygiene, and productivity ofdairy cows. Regardless ofmethod used to simulate overcrowding, the mean daily lying time was reduced. Feeding time tended to be affected, but the extent of reduction in feeding time was dependent on the method of increasing stocking density. Overall, these results indicate that each of the methods for imposing stocking density were equivalent in their effect on cow behavior (except rumination time), hygiene, and productivity.
The second study (Chapter 3) investigated the effect of stocking densities of 100 (1 cow per resting and feeding space), 113, 131, and 142% on the short-term behavior and productivity of Holstein dairy cows. Lying time and the percentage of rumination occurring within a freestall decreased and the number of displacements from the feed bunk increased as stocking density increased. These behavioral changes were not associated with changes in milk yield, feed intake, feeding time, or hygiene. Fecal cortisol metabolites were not indicative of a stress response. Short-term overcrowding alters some aspects of the behavior of dairy cows, but the biological consequences of these changes are not clear.
The third study (Chapter 4) investigated changes in feeding (defined by intake, feeding time, feed bin visits, feeding rate, and number of meals per day) and standing (time per day and bouts) behaviors and aggressive interactions at the feed bunk of healthy dairy cows in response to increased competition at the feeder during the 21 days following calving. Aggression increased and feeding rate tended to increase in response to treatments. Feeding and standing behaviors were unaffected.
The fourth study (Chapter 5) evaluated three indices (Cow Comfort Index, Stall Standing Index, and the Stall Use Index) used to determine cow comfort at stocking densities (number of cows per freestall within the pen) of 100, 113, 131, and 142%. The stall use index was determined to provide the most accurate assessment of cow comfort, due to its incorporation of the number of cows which were standing and not eating. At higher stocking densities, cow comfort index and stall standing index were unable to establish differences in cow comfort.
The first study (Chapter 2) investigated the effect ofthree methods for experimentally increasing stocking density (denial ofaccess to feeding and resting space; denial of feeding, resting, and alley space; and the addition of cows) on the behavior, hygiene, and productivity ofdairy cows. Regardless ofmethod used to simulate overcrowding, the mean daily lying time was reduced. Feeding time tended to be affected, but the extent of reduction in feeding time was dependent on the method of increasing stocking density. Overall, these results indicate that each of the methods for imposing stocking density were equivalent in their effect on cow behavior (except rumination time), hygiene, and productivity.
The second study (Chapter 3) investigated the effect of stocking densities of 100 (1 cow per resting and feeding space), 113, 131, and 142% on the short-term behavior and productivity of Holstein dairy cows. Lying time and the percentage of rumination occurring within a freestall decreased and the number of displacements from the feed bunk increased as stocking density increased. These behavioral changes were not associated with changes in milk yield, feed intake, feeding time, or hygiene. Fecal cortisol metabolites were not indicative of a stress response. Short-term overcrowding alters some aspects of the behavior of dairy cows, but the biological consequences of these changes are not clear.
The third study (Chapter 4) investigated changes in feeding (defined by intake, feeding time, feed bin visits, feeding rate, and number of meals per day) and standing (time per day and bouts) behaviors and aggressive interactions at the feed bunk of healthy dairy cows in response to increased competition at the feeder during the 21 days following calving. Aggression increased and feeding rate tended to increase in response to treatments. Feeding and standing behaviors were unaffected.
The fourth study (Chapter 5) evaluated three indices (Cow Comfort Index, Stall Standing Index, and the Stall Use Index) used to determine cow comfort at stocking densities (number of cows per freestall within the pen) of 100, 113, 131, and 142%. The stall use index was determined to provide the most accurate assessment of cow comfort, due to its incorporation of the number of cows which were standing and not eating. At higher stocking densities, cow comfort index and stall standing index were unable to establish differences in cow comfort.