Progress 10/01/11 to 10/01/16
Outputs
Target Audience:Potential target audiences are cattle producers at conferences and field days. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?As a preliminary study supporting Objective 3, an undergraduate scholar and myself completed a controlled trial assessing the effects of feeding level on metabolic rates of beef cattle. Two other undergraduates were hired to assist on all phases of the trial. In 2015, I also joined a USDA Multi-state committee on stress factors in animals. I traveled to the committee's annual meeting, presented the results from the preliminary trial, and presented my research which will be funded by a foundation, covering Objectives 2 and 3 of this project. How have the results been disseminated to communities of interest?The undergraduate scholar presented her work at an Undergraduate Scholar's conference and at a nutrition conference. The results were presented by the PI to a USDA Multistate committee and at research center Field Days. What do you plan to do during the next reporting period to accomplish the goals?The previous project periodfocused on heart rate as a surrogate indicator for metabolic rate. With the foundation grant and an equipment grant (for the respirometer) I now have the capablility to measure both. Because of the time and resources associated with adding measures of metabolic rates to this study, assessing behavior will be downplayed (Objective 1).
Impacts
What was accomplished under these goals?
In July 2015, I received a grant from a foundation to complete Objectives 2 and 3. I am in the process of looking for a graduate student. In 2015, I also joined a USDA Multistate committee on stress factors in animals. As a preliminary study supporting Objective 3, we completed a controlled trial assessing the effects of feeding level on metabolic rates of beef cattle. With the renewal of the project andthe foundation grant plus an equipment grant(for the respirometer) I will continue research. Because of the time and resources associated with adding measures of metabolic rates to this study, assessing behavior will be downplayed (Objective 1) in future research.
Publications
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Progress 10/01/14 to 09/30/15
Outputs
Target Audience:Assessing metabolic rates of cattle is central to this project. Using my recently acquired respirometer and portable metabolic chamber, an undergraduate scholar and two other undergraduates completed a study assessing the effect of altering feeding levels on metbolic rates of cattle. The undergraduate scholar presented her work at an Undergraduate Scholar's conference and at a nutrition conference. The results were presented by the PI to a USDA Multistate committee.A manuscript is being prepared. Potential target audiences are cattle producers at conferences and field days. Changes/Problems:The previous project focused on heart rate as a surrogate indicator for metabolic rate. With the foundation grant and an equipment grant (for the respirometer) I now have the capablility to measure both. Because of the time and resources associated with adding measures of metabolic rates to this study, assessing behavior will be downplayed (Objective 1). What opportunities for training and professional development has the project provided?As a preliminary study supporting Objective 3, an undergraduate scholar and myselfcompleted a controlledtrial assessing the effects of feeding level on metabolic rates of beef cattle. Two other undergraduates were hired to assist on all phases of the trial.In 2015, I also joined a USDA Multi-state committee on stress factors in animals. I traveled to the committee's annual meeting, presented the results from the preliminary trial, and presented myresearch which will be funded by a foundation, covering Objectives 2 and 3 of this project. How have the results been disseminated to communities of interest?From the preliminary trial, results have been communicated via a poster at an Undergraduate Scholar's Conference, and a Livestock Nutrition Conference. What do you plan to do during the next reporting period to accomplish the goals?The previous project focused on heart rate as a surrogate indicator for metabolic rate. With the foundation grant and an equipment grant (for the respirometer) I now have the capablility to measure both. Because of the time and resources associated with adding measures of metabolic rates to this study, assessing behavior will be downplayed (Objective 1).
Impacts
What was accomplished under these goals?
I have not been able to secure a federal grant to complete these objectives. In July 2015, I received a grant from a foundation to complete Objectives 2 and 3.I am in the process of looking for a graduate student. In 2015, I also joined a USDA Multi-state committee on stress factors in animals. As a preliminary study supporting Objective 3, we completed a controlledtrial assessing the effects of feeding level on metabolic rates of beef cattle.
Publications
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Progress 10/01/13 to 09/30/14
Outputs
Target Audience:
Nothing Reported
Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals? Regarding Objective 2, we will begin to measure metabolic rates of mature cattle at the mid-point of the four seasons. We will complete a preliminary trial on metabolic response of cattle to step-wise decreases and then increases in feeding level. This preliminary trial is related to Objective 3. Note, the initial goals of this project was based on the premise that heart rate can be used as a surrogate for metabolic rate. Since we now have the capability to measure metabolic rates, we will directly measure metabolic rates.
Impacts
What was accomplished under these goals?
A grant proposal was submitted May 2014 to accomplish Objectives 2 and 3, but it was not funded. In 2013, using my recently acquired respirometer and portable metabolic chamber (a small, enclosed horse trailer), a PhD student, an undergraduate and myself assessed metabolic rates of 9 calves (up to 250 kgs) of three different sizes, on two separate days one week apart and found a high correlation between days. In May 2014, an undergraduate and I attempted to do a preliminary trial with mature cattle (550 kgs) related to Objectives 2 and 3, but when we were ready to begin the trial, these mature cows would not enter the trailer. I have since acquired a much larger trailer, and we will conduct that preliminary trial in March 2015.
Publications
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Progress 01/01/13 to 09/30/13
Outputs
Target Audience: Assessing metabolic rates of cattle is central to this project. Using my recently acquired respirometer and portable metabolic chamber, a PhD student, an undergraduate and myself assessed metabolic rates of 9 cattle, of three different sizes, on two separate days one week apart and found a high correlation between days. The PhD student wrote a proceedings paper, and gave an oral presentation on the trial at the Western Section American Society of Animal Science meeting in June. The undergraduate gave an oral presentation and developed a poster for an honor's conference. Changes/Problems: I have added the capability to measure metabolic rate along with the heart rate of beef cattle. We will correlate metabolic rate with heart rate; we assume they will be highly correlated within each animal. The respirometer quantifies metabolic rate, but it is a short-term measure (30-40 minutes per head). Heart rate transmitters work 24-7, 365 days a year. What opportunities for training and professional development has the project provided? The metabolic trials in February-March 2013 helped train a PhD student and an undergraduate. How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals? I have the resources to conduct some short-term trials with the portable metabolic chamber and respirometer, which will support Objectives 2 and 3, and whose results can be used to help underpin a research proposal. A Letter of Intent will be submitted in May to NIFA to accomplish all three objectives of the project proposal.
Impacts
What was accomplished under these goals?
A proposal was written and submitted to a foundation to acomplish Objectives 2 and 3, but it was not funded. At te time this project proposal was written, I intended to measure heart rate as a surrogate for metabolic rate. With my recently acquired respirometer, we will be able to measure metabolic rates in addition to heart rates to address the questions posed in Objectives 2 and 3. We successfully conducted trials with the portable metabolic chamber and respirometer in February-March 2013.
Publications
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2013
Citation:
A.R. Vogstad, B.E. Olson, T.T. Wurtz, and G.C. Duff. 2013. Use of a portable metabolic chamber for measuring resting metabolic rates in cattle of varying body weights. Proc. Western Section, American Society of Animal Science. June, Bozeman, MT.
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Progress 01/01/12 to 12/31/12
Outputs
OUTPUTS: Activity, and therefore outputs, on this project was minimal in 2012. I received an equipment grant in late 2011, which allowed me to acquire a respirometer, which was delivered in July. The respirometer is integral to the project. I attended a week long workshop on the respirometer in June. I did not receive a grant which would have covered operations and personnel for my respirometer-related research. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: My primary outreach on this MAES research project was an invited presentation at the Western Section American Society of Animal Science annual meeting in Phoenix. The topic was "An evaluation of cold stress on ruminant nutritional requirements". There were over 100 in the audience, primarily other scientists. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
My primary outreach on this MAES research project was an invited presentation at the Western Section American Society of Animal Science annual meeting in Phoenix. The topic was "An evaluation of cold stress on ruminant nutritional requirements".
Publications
- No publications reported this period
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Progress 01/01/11 to 12/31/11
Outputs
OUTPUTS: Activity, and therefore outputs, on this project has been minimal the last 5 years for the following reasons. From August 2006 until August 2010, I was interim head of the Animal and Range Sciences Department at Montana State University, leaving little time for research. Second, I submitted a grant proposal to be able to hire a post-doctoral researcher or graduate students to help conduct this project, but it was not awarded. An equipment grant, integral to the future of the project, was awarded in late 2011. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
My primary outreach on this MAES research project was an invited presentation in western North Dakota in December 2009. Most of the 100+ were ranchers from the region. My talk created considerable interest and discussion. However, I have no way to assess whether that engendered a change in actions or conditions, but I know that I caused many audience members to think about more cost-efficient alternatives to wintering cattle.
Publications
- No publications reported this period
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Progress 01/01/10 to 12/31/10
Outputs
OUTPUTS: Activity, and therefore outputs, on this project has been minimal the last 4.5 years for the following reasons. From August 2006 until August 2010, I was interim head of the Animal and Range Sciences Department at Montana State University, leaving little time for research. Second, I have not received a competitive grant in this time period to be able to hire a post-doctoral researcher to help conduct this project. In December 2009, I was an invited speaker at a two day workshop in western North Dakota. Some of my materials will be incorporated into a cattle management book, and seminars by Dr. Jim Gerrish, a former academic and currently a grazing cattle consultant. In 2007, I was invited to southern Sweden to present 2-3 talks on winter grazing at each of five locations. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
My primary outreach on my research project in 2009 was the invited presentation in western North Dakota in December. Most of the 100 or so participants were ranchers from the region. My talk created considerable interest and discussion. However, I have no way to assess whether that engendered a change in actions or conditions, but I know that I caused many audience members to think about more cost-efficient alternatives to wintering cattle.
Publications
- No publications reported this period
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Progress 01/01/09 to 12/31/09
Outputs
OUTPUTS: The goal of the project is to use certain behavioral (activity patterns, position, orientation) and physiological (heart rate, back fat, weight, body condition) measures to determine how free-ranging beef cattle tolerate winter conditions without affecting reproductive performance. Activity on this project has been minimal the last 3.5 years for the following reasons. First, since August 2006, I have been the interim head of the Animal and Range Sciences Department at Montana State University, leaving little time for research. Second, I have not received a competitive grant in this time period to be able to hire a post-doctoral researcher to help conduct this project. In December 2009, I was an invited speaker at a two day workshop in western North Dakota. Some of my materials will be incorporated into a cattle management book, and seminars by Dr. Jim Gerrish, a former academic and currently a grazing cattle consultant. PARTICIPANTS: I am the primary person responsible for the project. My current status as the interim head of the Animal and Range Sciences Department at Montana State University has left little time to devote to the project. I have communicated with others about potential collaboration in the area of winter grazing, metabolism, etc. once I am no longer interim head. TARGET AUDIENCES: Target audiences are peer-scientists, stakeholders/clientele, and graduate- and undergraduate students. I have received inquiries regarding my previous, related research on this project from scientists in Scotland, New Zealand, and Sweden. Besides my numerous publications over the years related to this project, I present the findings when asked, such as I did in December in North Dakota. PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
My primary outreach on my research project in 2009 was the invited presentation in western North Dakota in December. Most of the 100 or so participants were ranchers from the region. My talk created considerable interest and discussion. I have no way to assess whether that engenders a change in actions or conditions, but I know that I caused many audience members to think about more cost-efficient alternatives to wintering cattle.
Publications
- No publications reported this period
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: The goal of the project is to use certain behavioral (activity patterns, position, orientation) and physiological (heart rate, back fat, weight, body condition) measures to determine how free-ranging beef cattle tolerate winter conditions without affecting reproductive performance. Activity on this project has been minimal the last 2.5 years for the following reasons. First, since August 2006, I have been the interim head of the Animal and Range Sciences Department at Montana State University, leaving me little time for research. Second, I have not received a competitive grant in this time period to be able to hire a post-doctoral researcher to help conduct this project. PARTICIPANTS: Dr. Bret Olson is the primary participant on this project but has been unable to commit time to the project because of his current administrative and teaching responsibilities. TARGET AUDIENCES: Potential target audiences are peer-scientists, stakeholders/clientele, and graduate- and undergraduate students. I have received inquiries regarding previous related research on this project from scientists in Scotland, New Zealand, and Sweden. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
My proposed research has the potential to greatly alter winter feeding practices in northern latitudes in the U.S. Regarding a potential change in managing cattle during winter, if cattle were not concentrated during winter feeding in the colder parts of the U.S., there would be higher net returns for livestock producers, more water during summer in streams and rivers (less irrigated hay needed), and higher water quality because many winter livestock feeding operations occur close to or along streams and rivers.
Publications
- No publications reported this period
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Progress 01/01/07 to 12/31/07
Outputs
OUTPUTS: From the thermal balance model we developed, we compared our model predictions with heat production measured in three empirical studies; in all cases our model predictions were similar to those reported. To help validate this thermal balance model, we modified thermal imaging software designed for non-living organisms, and applied this thermal imaging software to cattle grazing winter range under various scenarios. This last study was the third publication from a M.S. thesis. This most recent study and several preceding, related studies were the foundation for five invited presentations in southern Sweden in September 2007. At the different locations, the audience varied from mostly producers with some agricultural regulators to mostly researchers. While in Sweden, I had several informal counseling sessions with producers and others. Current policies in Sweden require livestock producers to provide housing for their animals during winter. Our results from previous studies,
model predictions, and thermal imaging software indicate that this may not be necessary. This study led to collaboration between myself and a Swedish DVM/PhD. I have had inquiries from researchers in Scotland and New Zealand regarding our research. In Sweden, my Powerpoint presentations were copied so that my hosts could access the material in the future. Since my trip last September, my Swedish collaborator told me that my invited presentations on our winter research is having an impact on altering some of the Swedish winter livestock housing regulations. Many producers in western North America "overfeed" their livestock during winter. Our previous research and our applying imaging software could be used to convince some that they can reduce or eliminate feeding without lowering productivity. However, this is a strong paradigm to overcome. Reducing or eliminating winter feeding would lower costs and reduce negative effects associated with concentrated livestock feeding during winter.
PARTICIPANTS: Bret Olson, Project Director, was responsible for conceptual design, support, and completing manuscript for publication. Elai Keren, Graduate Student, conducted the field work and quantitative analyses, modified imaging software, and completed thesis which included this objective. Per Michanek, Swedeish DVM, PhD, was a non-formal collaborator. Dr. Michanek organized, and was my host, on my trip to Sweden in 2007 in which I presented five talks throughout the southern part of the country.
TARGET AUDIENCES: Target audiences are livestock producers in cold climates. Many of these producers are barely making a profit. Anything that can lower their costs, withour reducing reproductive performance, will increase net returns. In Sweden, some livestock producers have gone out of business because of livestock winter-housing policies. So far, the science-based knowledge from this research has been presented at a few conferences in previous years, and in extension/outreach related form at five venues in Sweden in 2007.
PROJECT MODIFICATIONS: None.
Impacts
Regarding a potential change in knowledge, the ideas, concepts, and research in my invited talks in Sweden created considerable discussion during my talks. Regulators probably were not comfortable with the implications of my research, livestock producers appreciated implications for great cost-savings. Under their previous/current policy, some producers could not afford to house all of their livestock to meet policy; many went out of business. Regarding a potential change in actions, my Swedish collaborator informed me that regulators are considering changing their policies on winter livestock housing requirements based on my winter research. I am not sure of the actual current status of their policies. My research has the potential to greatly alter winter feeding practices in northern latitudes in the U.S. Regarding a potential change in conditions, if cattle were not concentrated during winter feeding in the colder parts of the U.S., there would be higher net returns
for livestock producers, more water during summer in streams and rivers (less irrigated hay needed), and higher water quality because many winter livestock feeding operations occur close to or along streams and rivers.
Publications
- Keren EN, Olson BE (2007) Applying thermal imaging software to cattle grazing winter range. J Thermal Biol 32:204-211
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Progress 01/01/06 to 12/31/06
Outputs
Cattle may graze foothill rangelands in northern latitudes as an alternative to feeding hay. However, winter winds may increase weight loss and lower body condition scores. In 2005, we refined a simple thermal balance equation to model heat exchange of free-ranging cattle during winter). We accounted for the complex interactions between animal behavior and the changing natural environment by applying the components of the model to a rotating ellipsoid representing a cow at different orientations to the sun and wind. Correlation coefficients between predicted standard operative temperature and measured surface temperature ranged from 0.82 on an individual basis to 0.88 on a herd average basis, indicating the model successfully quantifies heat exchanges of cattle exposed to cold conditions in the field. From the model we developed, we compared our model predictions with heat production measured in three empirical studies; in all cases our model predictions were similar
to those reported. Model simulations indicated that behaviors, such as lying down and orientation to the sun, mitigate the effects of extreme weather. For many combinations of winter weather variables, metabolic requirements increased only slightly due to cold exposure of mature beef cattle in a near maintenance state. Our model indicates that solar radiation contributes strongly to the thermal balance of a cow. This thermal balance model will provide insight into metabolic requirements of beef cattle during winter. Two manuscripts were published in 2006. One related manuscript is "in press", a fourth has been accepted.
Impacts
Our comprehensive thermal balance model may be used to predict metabolic requirements based on behavioral adjustments. Although the model was developed for cattle grazing winter range, it may apply whenever results from controlled environments are extrapolated to a natural environment setting. Our model predicted metabolic requirements in winter similar to those measured in three empirical studies. Predicted requirements increase only slightly when mature beef cattle in a maintenance state are exposed to cold. For many combinations of winter weather, predicted requirements were close to or lower than known basal metabolic rate. Thus, previous work may overestimate requirements for cattle acclimated to grazing winter range. Solar radiation lowers metabolic requirements, especially on cold, clear days. Our model emphasizes the contribution of the irradiative environment to a cow's ability to conserve energy in winter, and illustrates the benefits of considering solar
radiation when selecting winter pastures or husbandry practices.
Publications
- Keren EN, Olson BE (2006) Thermal balance of cattle grazing winter range: model development. J Thermal Biol 31:371-377.
- Keren EN, Olson BE (2006) Thermal balance of cattle grazing winter range: model application. J Anim Sci 84:1238-1247.
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Progress 01/01/05 to 12/31/05
Outputs
Cattle may graze foothill rangelands in northern latitudes as an alternative to feeding hay. However, winter winds may increase weight loss and lower body condition scores. In 2005, we refined a simple thermal balance equation to model heat exchange of free-ranging cattle during winter). We accounted for the complex interactions between animal behavior and the changing natural environment by applying the components of the model to a rotating ellipsoid representing a cow at different orientations to the sun and wind. Correlation coefficients between predicted standard operative temperature and measured surface temperature ranged from 0.82 on an individual basis to 0.88 on a herd average basis, indicating the model successfully quantifies heat exchanges of cattle exposed to cold conditions in the field. From the model we developed, we compared our model predictions with heat production measured in three empirical studies; in all cases our model predictions were similar
to those reported. Model simulations indicated that behaviors, such as lying down and orientation to the sun, mitigate the effects of extreme weather. For many combinations of winter weather variables, metabolic requirements increased only slightly due to cold exposure of mature beef cattle in a near maintenance state. Our model indicates that solar radiation contributes strongly to the thermal balance of a cow. This thermal balance model will provide insight into metabolic requirements of beef cattle during winter.
Impacts
Our comprehensive thermal balance model may be used to predict metabolic requirements of beef cattle based on behavioral adjustments. Although the model was developed for cattle grazing winter range, it may apply whenever results from controlled environments are extrapolated to a natural environment setting. Our model predicted metabolic requirements in winter similar to those measured in three empirical studies. Predicted requirements increase only slightly when mature beef cattle in a maintenance state are exposed to cold. For many combinations of winter weather, predicted requirements were close to or lower than known basal metabolic rate. Thus, previous work may overestimate requirements for cattle acclimated to grazing winter range. Solar radiation lowers metabolic requirements, especially on cold, clear days. Our model emphasizes the contribution of the irradiative environment to a cow's ability to conserve energy in winter, and illustrates the benefits of
considering solar radiation when selecting winter pastures or husbandry practices.
Publications
- Keren EN, Olson BE 2005. (In press) Thermal balance of cattle grazing winter range: model development. J Thermal Biol
- Keren EN, Olson BE 2005. (In press) Thermal balance of cattle grazing winter range: model application. J Anim Sci
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Progress 01/01/04 to 12/31/04
Outputs
Cattle may graze foothill rangelands in northern latitudes as an alternative to feeding hay. However, winter winds may increase weight loss and lower body condition scores. Our initial objective had been to determine whether exposure to wind stresses mature (5-7-year-old) pregnant beef cows grazing foothill winter range. Diurnal activity patterns varied greatly from day to day and were correlated with weather. Or example, time spent grazing ranged from 18% to 96%. Time spent lying down ranged from 0% to 39%. On cold days cattle oriented perpendicular to the sun to maximize heat gain. On windy days, they oriented parallel with the wind to minimize heat loss. We have developed and validated a thermal balance model, including net radiation, ambient temperature, cattle surface temperature, latent and sensible heat loss, conduction, storage, and metabolic heat, which identifies environmental conditions when cattle gain heat from and lose heat to their winter environment.
The model predicts metabolic rates similar to metabolic rates of bison and beef cattle measured under controlled, cold conditions. We are in the process of applying the model to hypothetical scenarios incorporating different orientations and activity patterns on a daily basis. This thermal balance model will provide insight into metabolic requirements and weight change under different winter conditions.
Impacts
Cattle activity patterns and orientation are highly responsive to weather which may explain minimal changes in backfat, body weight, immune response, and reproductive efficiency in one of our earlier studies. Our model indicates that cattle benefit considerably from solar radation during winter, which lowers their need to increase intake, or use endogenous reserves. Increased winter grazing, where feasible, will help lower winter feed costs.
Publications
- No publications reported this period
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Progress 01/01/03 to 12/31/03
Outputs
Cattle may graze foothill rangelands in northern latitudes as an alternative to feeding hay. However, winter winds may increase weight loss and lower body condition scores. Our initial objective had been to determine whether exposure to wind stresses mature (5-7-year-old) pregnant beef cows grazing foothill winter range. Diurnal activity patterns varied greatly from day to day and were correlated with weather. Or example, time spent grazing ranged from 18% to 96%. Time spent lying down ranged from 0% to 39%. On cold days cattle oriented perpendicular to the sun to maximize heat gain. On windy days, they oriented parallel with the wind to minimize heat loss. We are continuing to develop a thermal balance model, including net radiation, ambient temperature, cattle surface temperature, latent and sensible heat loss, conduction, storage, and metabolic heat, which identifies environmental conditions when cattle gain heat from and lose heat to their winter environment. For
example, on relatively warm, sunny days, net radiation absorbed by cattle can range from 4 to 6x (280-420 W m-2) basal metabolic heat production (70 W m-2). Once refined, this thermal balance model will incorporate different orientations and activity patterns on a daily basis to further refine the model. This thermal balance model will provide insight into metabolic requirements, weight change, and reproductive efficiency under different winter conditions.
Impacts
Cattle activity patterns and orientation are highly responsive to weather, which may explain minimal changes in backfat, body weight, immune response, and reproductive efficiency in one of our earlier studies. Our model indicates that cattle benefit considerably from solar radiation during winter, which lowers their need to increase intake, or use endogenous reserves. Increased winter grazing, where feasible, could help lower winter feed costs.
Publications
- No publications reported this period
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Progress 01/01/02 to 12/31/02
Outputs
Cattle may graze foothill rangelands in northern latitudes as an alternative to feeding hay. However, winter winds may increase weight loss and lower body condition scores. Our initial objective had been to determine whether exposure to wind stresses mature (5-7-year-old) pregnant beef cows grazing foothill winter range. Diurnal activity patterns varied greatly from day to day and were correlated with weather. Or example, time spent grazing ranged from 18% to 96%. Time spent lying down ranged from 0% to 39%. On cold days cattle oriented perpendicular to the sun to maximize heat gain. On windy days, they oriented parallel with the wind to minimize heat loss. We have developed a simple thermal balance model, including net radiation, ambient temperature, cattle surface temperature, latent and sensible heat loss, conduction, storage, and metabolic heat, which identifies environmental conditions when cattle gain heat from and lose heat to their winter environment. For
example, on relatively warm, sunny days, net radiation absorbed by cattle can range from 4 to 6x (280-420 W m-2) basal metabolic heat production (70 W m-2). This simple energy balance may provide insight into metabolic requirements, weight change, and reproductive efficiency under different winter conditions.
Impacts
Windbreaks were of minimal benefit to cattle grazing foothill rangelands during a Montana winter. Cattle activity patterns and orientation were highly responsive to weather, which may explain minimal changes in backfat, body weight, immune response, and reproductive efficiency. Cattle may benefit considerably from the winter sun, which lowers their need to increase intake, or use endogenous reserves. Increased winter grazing could help lower winter feed costs.
Publications
- Olson, B.E. and Wallander, R.T. 2002. Diurnal activity patterns of cattle grazing foothill winter range in Montana. Can. J. Anim. Sci. 82:491-501
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Progress 01/01/01 to 12/31/01
Outputs
Cattle may graze foothill rangelands in northern latitudes as an alternative to feeding hay. However, winter winds may increase weight loss and lower body condition scores. Our initial objective had been to determine whether exposure to wind stresses mature (5-7-year-old) pregnant beef cows grazing foothill winter range. As indicators of stress, we measured heat loss from animals in different positions and orientations, behavior and activity patterns, and changes in backfat, body weight, blood profiles, immune response, and reproductive efficiency. A small windbreak was erected in four of eight small pastures. All four winters, cattle with and without access to windbreaks had similar changes in weight, backfat, body condition score, and immune response, indicating those without windbreaks were not experiencing stress. Diurnal activity patterns varied greatly from day to day and were correlated with weather. On cold days cattle oriented perpendicular to the sun to
maximize heat gain. On windy days, they oriented parallel with the wind to minimize heat loss. We have developed a simple thermal balance model, including net radiation, ambient temperature, cattle surface temperature, latent and sensible heat loss, conduction, storage, and metabolic heat, which identifies environmental conditions when cattle gain heat from and lose heat to their winter environment. For example, on relatively warm, sunny days, net radiation absorbed by cattle can range from 4 to 6x (280-420 W m-2) basal metabolic heat production (70 W m-2). This simple energy balance may provide insight into metabolic requirements, weight change, and reproductive efficiency under different winter conditions.
Impacts
Windbreaks were of minimal benefit to cattle grazing foothill rangelands during a Montana winter. Cattle activity patterns and orientation were highly responsive to weather, which may explain minimal changes in backfat, body weight, immune response, and reproductive efficiency. Cattle may benefit considerably from the winter sun, which lowers their need to increase intake, or use endogenous reserves. Increased winter grazing could help lower winter feed costs.
Publications
- Olson BE, Wallander RT (2002) Diurnal activity patterns of cattle grazing foothill winter range in Montana. Can J Anim Sci - accepted for publication
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Progress 01/01/00 to 12/31/00
Outputs
Cattle may graze foothill rangelands in northern latitudes as an alternative to feeding hay. However, winter winds may increase weight loss and lower body condition scores. Our initial objective had been to determine whether exposure to wind stresses mature (5-7-year-old) pregnant beef cows grazing foothill winter range. As indicators of stress, we measured heat loss from animals in different positions and orientations, behavior and activity patterns, and changes in backfat, body weight, blood profiles, immune response, and reproductive efficiency. A small windbreak was erected in four of eight small pastures. During our first two winters (1996-1997, 1997-1998), four mature, pregnant cows grazed each of these small pastures for 6-7 weeks. During our second two winters (1998-1999, 1999-2000), four young (coming 3-year-old) cattle grazed each of these small pastures for 7 weeks. All four winters, cattle with and without access to windbreaks had similar changes in
weight, backfat, body condition score, and immune response. Diurnal activity patterns varied greatly from day to day and were correlated with weather. On cold days cattle oriented perpendicular to the sun to maximize heat gain. On windy days, they oriented parallel with the wind to minimize heat loss. We are developing a simple energy balance model which will identify when cattle are gaining heat from or losing heat to their winter environment, which will have implications for metabolic requirements, weight change, and reproductive efficiency.
Impacts
Windbreaks are of minimal benefit to cattle grazing foothill rangelands during winter. Cattle activity patterns and orientation were highly responsive to weather, which may explain minimal changes in backfat, body weight, immune response, and reproductive efficiency. Cattle gain considerable energy from the sun during winter, which lowers need to increase intake, or use endogenous reserves. Increased winter grazing could lower winter feed costs.
Publications
- Olson, B.E., Wallander, R.T. and Paterson, J.A. 2000. Do windbreaks minimize stress on cattle grazing foothill winter range? Can J Anim Sci 80:265-272
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Progress 01/01/99 to 12/31/99
Outputs
Cattle may graze foothill rangelands in northern latitudes as an alternative to feeding hay. However, winter winds may increase weight loss and lower body condition scores. Our initial objective had been to determine whether exposure to wind stresses mature (5-7-year-old) pregnant beef cows grazing foothill winter range. As indicators of stress, we measured heat loss from animals in different positions and orientations, behavior and activity patterns, and changes in backfat, body weight, blood profiles, immune response, and reproductive efficiency. A small windbreak was erected in four of eight small pastures. During our first two winters (1996-1997, 1997-1998), four mature, pregnant cows grazed each of these small pastures for 6-7 weeks. For the last two winters (1998-1999, 1999-2000), four young (coming 3-year-old) cattle grazed each of these small pastures for 7 weeks. All four winters, cattle with and without access to windbreaks had similar changes in weight,
backfat, body condition score, and immune response. Diurnal activity patterns varied greatly from day to day and were correlated with weather. On cold days cattle oriented perpendicular to the sun to maximize heat gain. On windy days, they oriented parallel with the wind to minimize heat loss.
Impacts
Our results indicate that windbreaks are of minimal benefit to cattle grazing foothill rangelands during winter. Cattle activity patterns and orientation are highly responsive to daily weather, which presumably explains the minimal changes in backfat, body weight, blood profiles, immune response, and reproductive efficiency.
Publications
- Olson, B.E., Wallander, R.T., Paterson, J.A. 2000 Do windbreaks minimize stress on cattle grazing foothill winter range? Can J Anim Sci
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Progress 01/01/98 to 12/31/98
Outputs
Cattle may graze foothill rangelands in northern latitudes as an alternative to feeding hay. We completed the third winter of a study assessing the effect of windbreaks on minimizing stress on cattle grazing foothill winter range. In contrast to the first two winters, this last winter (1998-1999) we used coming 3-year-old cattle. They are still growing while pregnant and would be expected to exhibit stress more than mature cattle. As part of this study (MONB00170), we are assessing forage quality and quantity, developing daily activity budgets, and measuring enviromental conditions. Along with data from the first two winters, this information will be used to develop a model that will predict nutrient availability and nutrient demand for cattle grazing foothill rangelands. Overall, the results will indicate under what conditions cattle can graze rangelands during winter reducing feed costs for livestock producers.
Impacts
(N/A)
Publications
- No publications reported this period
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Progress 01/01/97 to 12/31/97
Outputs
We completed the second winter of a study assessing the effect of windbreaks on minimizing stress for cattle grazing winter range (Project 170). As part of this study, we are assessing forage quality and quantity, developing cattle activity budgets, and measuring environmental conditions. This study will be repeated the winter of 1998-1999. This information will be used to identify to the extent to which cattle select green over dead material on winter range (Objective 1 - Project 176), and to develop a model that will predict nutrient availability and nutrient demand for cattle grazing foothill winter range (Objective 4 - Project 176). This information will be used to indicate that cattle can graze winter rangeland which will lower winter feed costs for livestock producers.
Impacts
(N/A)
Publications
- BEAVER, J.M., OLSON, B.E. 1997. Winter range use by cattle of different ages in southwestern Montana. Appl. Anim. Behav. Sci.
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Progress 01/01/96 to 12/30/96
Outputs
We began a study assessing the effect of windbreaks on minimizing stress for cattle grazing winter range. As part of this study, we are assessing forage quality and quantity, developing cattle activity budgets, and measuring environmental conditions. This study will be repeated the next two winters (1997-1998), 1998-1999). This information will be used to identify to the extent to which cattle select green over dead material on winter range (Objective 1), and to develop a model that will predict nutrient availability and nutrient demand for cattle grazing winter range (Objective 4).
Impacts
(N/A)
Publications
- HOUSEAL, G. A., B.E.OLSON. 1996. Nutritive value of live and dead components of two bunchgrasses. Can. J. Anim. Sci. In press.
- BEAVER, J. M., B.E.OLSON. 1996. A simple index of standard operative temperature for mule deer and cattle in winter. J. Therm. Biol. 21:345-352.
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Progress 01/01/95 to 12/30/95
Outputs
We compared the use of experienced (7-8 year old) and inexperienced (3 year-old)cows on winter range. At regular intervals during winter, we measured three environmental parameters at cow location and along three transects representing a range of environmental conditions within the pasture. We also did activity budgets for each group of cows, and compared their use of different environmental protection areas with GIS. We collected forage samples and rumen extrusa samples at monthly intervals during winter (December 1994 through February 1995) to determine the green:dead ratio of forage available and forage selected by cattle. We completed our alfalfa seeding study to determine if winter cattle grazing encourages the establishment of a competitive forb. We used alfalfa as a surrogate of a noxious weed.
Impacts
(N/A)
Publications
- Olson BE, Olson-Rutz KM (1996) Winter feeding and grazing practices of sheep in Montana. Can J Anim Sci - submitted
- Olson BE, Olson-Rutz KM (1996) Beef cattle winter feeding and grazing practices in Montana. Can J Anim Sci - submitted
- Olson BE, Jacobsen JS (1996) Plasticity of high- and low nutrient adapted grasses to added S and N. Oikos - in prep.
- Houseal GA, Olson BE (1995) Cattle use of microclimates on a northern latitude winter range. Can J Anim Sci - in-press
- Soder KJ, Thomas VM, Kott RW, Hatfield PG, Olson BE (1995) Influence of energy or protein supplementation during midpregnancy on forage intake of ewes grazing Montana winter range. J Anim Sci 73:2853-2859
- Houseal GA, Olson BE (1996) Nutritive value of live and dead components of two bunchgrasses. J Range Manage - accepted
- Beaver JM, Olson BE (1996) Winter range use by different aged cattle in southwestern Montana. Appl Anim Behav Sci - accepted
- Beaver JM, Olson BE (1996) A simple index of standard operative temperature for mule deer and cattle in winter. J Therm Biol - submitted
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Progress 01/01/94 to 12/30/94
Outputs
We compared the use of experienced (7-8 year old) and inexperienced (3 year old)cows on winter range. At regular intervals during winter, we measured three environmental parameters at cow location and along three transects representing a range of environmental conditions within the pasture. We also did activity budgets for each group of cows, and compared their use of different environmental protection areas with GIS. We collected forage samples and rumen extrusa samples at monthly intervals during winter to determine the green:dead ratio of forage available and forage selected by cattle. We repeated our alfalfa seeding study to determine if winter cattle grazing encourages the establishment of a competitive forb. We used alfalfa as a surrogate of a noxious weed.
Impacts
(N/A)
Publications
- HOUSEAL, G.A., B.E. OLSON. 1994. Cattle use of microclimates on a northern latitude winter range. Oecologia.
- HOUSEAL, G.A., B.E. OLSON. 1994. Nutritional value of live and dead components of two bunchgrasses. J. Range Manage.
- OLSON, B.E., M. WATTS, K. OLSON-RUTZ. 1994. Winter feeding and grazing practices of sheep in Montana. Agricultural Systems.
- OLSON, B.E., J. JACOBSEN. 1994. Effects of pyrite on high and low-nutrient adapted plants. Oecologia.
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