Manure application increases pasture crop production and minimizes manure storage costs. Excess N... more Manure application increases pasture crop production and minimizes manure storage costs. Excess N not absorbed by pasture vegetation can leach past the root zone and into ground water. A yearlong study was conducted on grazing pastures at 2 dairy farms to monitor potential nitrate (NO 3) movement from the surface through the soil profile toward ground water. Precipitation, irrigation, manure application, and grazing were compared with NO 3 movement. Both pastures were part of rotational grazing systems and receive periodic applications of manure by cattle and by typical manure application equipment. Sampling devices were located in the center of operational fields. A total of 9 sampling wells (lysimeters) were installed at depths of 1, 1.3, and 1.6 m below the surface of each pasture. Each depth was replicated 3 times at each site. Water samples were taken every 2 wk at each site and tested for NO 3-N. Farm A applied a total of 600 kg N/ha throughout the year and farm B applied approximately 300 kg/ha. On
Cryopreserved spermatozoa from 8 bulls were used to examine the interrelationships among flow cyt... more Cryopreserved spermatozoa from 8 bulls were used to examine the interrelationships among flow cytometric spermatozoal quality assessments and classical semen quality parameters and nonreturn rate estimates of fertility. The integrity of the sperm cell membrane and the functional capacity of the mitochondria were quantified by flow cytometry after concurrent staining with carboxydimethylfluorescein diacetate (CDMFDA), propidium iodide (PI), and rhodamine 123 (R123). For each sample a total of 10,000 stained spermatozoa were simultaneously quantified for the intensity of their green and red fluorescence. Three straws from each bull were each examined initially and following incubation at 37 degrees C for 3 hours to assess the rate of senescence. The proportion of spermatozoa retaining membrane integrity and having functional mitochondria, as determined by CDMFDA and R123 staining, were compared with classical semen quality assessments (sperm motility, acrosomal status, cellular and head morphology, presence of vacuoles/craters and cytoplasmic droplets) and with fertility (nonreturn to estrus rates). For individual ejaculates nonreturn rates, the range was from 61.8 to 78.8%, whereas the cumulative rates of several ejaculates for each bull ranged from 71.3 to 83.5%. The proportion of spermatozoa with functional membranes and mitochondria were positively correlated with the percentage of spermatozoa with normal morphology (r=0.82; P=0.01) and motility after 4 hours of incubation (r=0.78; P=0.02), but not with the estimates of fertility. The actual number of spermatozoa per straw staining with CDMFDA and R123 after 4 hours of incubation at 37 degrees C was correlated with the percentage of spermatozoa with normal morphology (r=0.73; P=0.04). Multiple regression equations indicated that combinations of semen quality measurements could be useful in estimating fertilizing potential.
Introduction Dairy farmers in the coastal areas of Oregon rely heavily on pastures for both grazi... more Introduction Dairy farmers in the coastal areas of Oregon rely heavily on pastures for both grazing and silage production. As managers, they ideally should be matching the nutrients supplied in the form of manure to their forage crops for maximum productivity, without over applying any one particular nutrient. Several studies have shown the timing of manure application is important in the uptake of nutrients from the soil. The more frequent applications increase nutrient removal and total crop yield. Perennial plants have also been shown more effective in removing nutrients when compared to annuals crops with similar requirements (Knezack and Miller, 1976; Hensler, 1970). Some of the more modern forage grasses have limited to no data on nutrient utilization. Moore and Gamroth (1995) showed some grass varieties in the Willamette Valley, Oregon, treated with 300lbs/N per acre in season removed over 400 lbs/N per acre in plant growth. In their study they also had a treatment of manure at 450-lbs/N per acre, with plant removal rates of nitrogen near 500 lbs/ N per acre. It was thought for years, forage grasses utilized only around 200 lbs up to 300 lbs /N acre for the highest producing grasses like orchard grasses. Most animal waste management plans written for pastured based dairies use estimates for manure produced and yields removed to design the waste plan. Landowners theoretically have been required to apply nitrogen (N) in quantities equal to what they remove annually in a crop. As concerns for water quality have increased, so has the need to demonstrate that the nutrients applied are equal to what is removed. Over the past year, a trial was conducted to develop a realistic plan for dairymen to document nutrient application and removal on pasture based dairies. This project was designed to be a model for documenting manure applications and forage removal in pasture-based dairies.
Well-preserved silage is characterized by reduced pH, greater lactic acid concentration, and redu... more Well-preserved silage is characterized by reduced pH, greater lactic acid concentration, and reduced ammonia (NH 3) concentration compared with silage that did not ferment well. Water soluble carbohydrates (WSC) are the primary fermentation substrate. In temperate grass forages, glucose, fructose, sucrose, and fructans are the primary WSC. New varieties of ryegrass have been developed in the United Kingdom to express high levels of WSC. The objective of this trial was to determine differences in fermentation characteristics of grasses with different WSC levels cut and processed as silage. Four perennial ryegrasses, 3 cultivars with a relatively greater WSC concentration (AberAvon, AberDart, and Elgon) and 1 cultivar commonly grown in Oregon, the control WSC (Linn), were planted. Three replicates of each grass were ensiled after morning and afternoon harvests. Each sample was packed, vacuum sealed, and ensiled for 60 d at 10°C. Fresh grass samples were taken from each cutting and analyzed before ensiling. Fresh grass WSC was greater in the 3 high WSC grass cultivars vs. Linn.
Dairy farmers use footbaths to control diseases of the hoof. When the footbaths are changed, the ... more Dairy farmers use footbaths to control diseases of the hoof. When the footbaths are changed, the solutions are dumped into the dairy manure handling system and applied to fields in the liquid manure system. The objective for this project was to survey 30 dairy farms in Oregon to evaluate CuSO 4 and ZnSO 4 use in footbaths. Soil samples were collected from 2 major fields at 15 cm deep and all samples were analyzed for Cu and Zn. Forages grown on the farm were sampled and analyzed for Cu and Zn, and manure was collected directly from milk cows and from the liquid manure storage system. All forages, soils, and manure were analyzed for Cu and Zn. Soil Cu concentrations ranged from 0.7 to 34.7 ppm, with an average of 5.7 ± 6.6 ppm. Soil Zn concentrations ranged from 0.6 to 41.8 ppm, with an average of 10.1 ± 9.3 ppm. Forage Cu concentrations ranged from 1 to 10 ppm, with an average of 3.4 ± 2.1 ppm, and forage Zn ranged from 3 to 51 ppm, with an average of 13.8 ± 10.3 ppm. Copper concentrations in fresh manure directly from milking cows were very consistent, at 10 ppm, and Cu in the manure storage ranged from 2 to 58 ppm, with an average of 10.3 ± 12 ppm. The use of CuSO 4 and ZnSO 4 in footbaths on dairies in Oregon continues to be a common practice. More than 75% of dairy soils tested were considered high (>2 ppm) in Cu concentration and 38% were extremely high (>5 ppm). Using CuSO 4 and ZnSO 4 in footbaths is creating potential long-term environmental and cropping challenges on many Oregon dairies.
Published July 2006. Reviewed March 2016. Please look for up-to-date information in the OSU Exten... more Published July 2006. Reviewed March 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published June 2007. Reviewed December 2014. Facts and recommendations in this publication may no... more Published June 2007. Reviewed December 2014. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Managing pastures on grazing dairies is a continuous challenge because pasture quality, quantity,... more Managing pastures on grazing dairies is a continuous challenge because pasture quality, quantity, and growth rate are changing daily. The objectives of this study were to document weekly pasture growth, forage quality, and performance to understand how to use this information to make management decisions on US dairies. One organic grazing dairy was studied for 3 consecutive years. Pastures were measured and mapped, and total standing DM was estimated weekly in all 22 pastures using a calibrated rising plate meter. Weekly grazing wedges were developed and were used to make grazing decisions that week. Paddocks grazed and residual pasture covers were recorded daily. Paddock grazing and residual heights were also included in the electronic recordkeeping. Dry matter yields ranged from 11,277 to 22,346 kg/ha per year and averaged 15,887 ± 1,919, 17,848 ± 1,966 and 17,956 ± 2,014 for each consecutive year. Daily growth rates ranged from 18 to 100 kg/ha per day throughout the season and averaged as high as 56 ± 20.3 kg/ha per day in yr 3. Pasture quality and productivity in Oregon is comparable to some of the most productive dairy pasture systems reported from around the world.
Dairy nutritionists have long known that forages with the same laboratory analysis could produce ... more Dairy nutritionists have long known that forages with the same laboratory analysis could produce significantly different performance in lactating cows. Neutral detergent fiber digestibility (NDFD) may explain much of this variation. The objectives of the study described here were to demonstrate NDFD variation between varieties of ryegrass and season of harvest and to use this information as the basis for an educational Extension program. Large differences in NDFD were found among 11 varieties of ryegrass. This information was used to change the way livestock rations are balanced and it is hoped will convince grass seeds companies to focus more on fiber digestibility.
Journal of Histochemistry & Cytochemistry, 1991
Several fluorescent probes, including derivatives of carboxyfluorescein, carbocyanine, ethidium, ... more Several fluorescent probes, including derivatives of carboxyfluorescein, carbocyanine, ethidium, and rhodamine, have been used to assess sperm viability. However, the effects of these fluorescent dyes on the metabolic activity of sperm cells have not been systematically examined. This study was conducted to determine the effect of specific fluorescent stains on the metabolic processes of sperm. Cryopreserved bovine sperm cells were thawed, fluorescently stained, and examined using metabolic and flow cytometric techniques. Sperm were stained with either rhodamine 123 (Rhod-123), the aliphatic cell-tracking compound PKH2-GL, dihydro-ethidium (HED), the bisbenzimide stain Hoechst 33342 (Ho33342), or left unstained. The stained samples were compared for metabolic activity, cell staining pattern, and fluorescent intensity over a 180-min period. Samples stained with HED, Ho33342, and PKH2-GL had less oxygen uptake when compared with the unstained sperm samples (p greater than 0.05). Unsta...
High-quality forages, such as alfalfa and grasses, are important for efficient milk production fr... more High-quality forages, such as alfalfa and grasses, are important for efficient milk production from dairy cows. Forages provide the effective fiber that is critical for good health and longevity. Inadequate effective fiber in the cow's diet is one reason for acidosis and milk fat ...
Increasing pasture diversity and spatially separated sowing arrangements can potentially increase... more Increasing pasture diversity and spatially separated sowing arrangements can potentially increase the dry matter intake of high-quality forages leading to improved animal production. This study investigated the effects of simple (two-species) and diverse (six-species) pastures planted either in mixed or spatially separated adjacent pasture strips on performance, N partitioning, and methane emission of dairy cows. Thirty-six mid-lactation Jersey cows grazed either (1) simple mixed, (2) simple spatially separated, (3) diverse mixed, or (4) diverse spatially separated pastures planted in a complete randomized block design with three replicates. Compared to simple pasture, diverse pasture had lower CP content but higher condensed tannins and total phenolic compounds with an overall positive effect on yield of milk solids, nitrogen utilization, including a reduction of N output from urine, and methane yields per dry matter eaten. The spatial separation increased legume and CP content in ...
Whether your goal is to manage manure application to balance for nitrogen or for phosphorus, know... more Whether your goal is to manage manure application to balance for nitrogen or for phosphorus, knowing how much nutrient you are applying is a crucial step toward ideal manure management. Determining the relationship between volume of waste and the amount of nutrients applied is essential. This publication describes how to calibrate waste-handling equipment and to calculate nutrient application rates. It covers typical equipment found on dairies and uses nitrogen in the examples. The same techniques can be used with phosphorus. Generally, it is desirable to apply no more than 100 pounds N per acre at a time. See the publications listed under "For more information" on page 6 to learn how to determine appropriate nutrient application rates for your situation.
Revised April 2004. Revised December 2014. Please look for up-to-date information in the OSU Exte... more Revised April 2004. Revised December 2014. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Manure application increases pasture crop production and minimizes manure storage costs. Excess N... more Manure application increases pasture crop production and minimizes manure storage costs. Excess N not absorbed by pasture vegetation can leach past the root zone and into ground water. A yearlong study was conducted on grazing pastures at 2 dairy farms to monitor potential nitrate (NO 3) movement from the surface through the soil profile toward ground water. Precipitation, irrigation, manure application, and grazing were compared with NO 3 movement. Both pastures were part of rotational grazing systems and receive periodic applications of manure by cattle and by typical manure application equipment. Sampling devices were located in the center of operational fields. A total of 9 sampling wells (lysimeters) were installed at depths of 1, 1.3, and 1.6 m below the surface of each pasture. Each depth was replicated 3 times at each site. Water samples were taken every 2 wk at each site and tested for NO 3-N. Farm A applied a total of 600 kg N/ha throughout the year and farm B applied approximately 300 kg/ha. On
Cryopreserved spermatozoa from 8 bulls were used to examine the interrelationships among flow cyt... more Cryopreserved spermatozoa from 8 bulls were used to examine the interrelationships among flow cytometric spermatozoal quality assessments and classical semen quality parameters and nonreturn rate estimates of fertility. The integrity of the sperm cell membrane and the functional capacity of the mitochondria were quantified by flow cytometry after concurrent staining with carboxydimethylfluorescein diacetate (CDMFDA), propidium iodide (PI), and rhodamine 123 (R123). For each sample a total of 10,000 stained spermatozoa were simultaneously quantified for the intensity of their green and red fluorescence. Three straws from each bull were each examined initially and following incubation at 37 degrees C for 3 hours to assess the rate of senescence. The proportion of spermatozoa retaining membrane integrity and having functional mitochondria, as determined by CDMFDA and R123 staining, were compared with classical semen quality assessments (sperm motility, acrosomal status, cellular and head morphology, presence of vacuoles/craters and cytoplasmic droplets) and with fertility (nonreturn to estrus rates). For individual ejaculates nonreturn rates, the range was from 61.8 to 78.8%, whereas the cumulative rates of several ejaculates for each bull ranged from 71.3 to 83.5%. The proportion of spermatozoa with functional membranes and mitochondria were positively correlated with the percentage of spermatozoa with normal morphology (r=0.82; P=0.01) and motility after 4 hours of incubation (r=0.78; P=0.02), but not with the estimates of fertility. The actual number of spermatozoa per straw staining with CDMFDA and R123 after 4 hours of incubation at 37 degrees C was correlated with the percentage of spermatozoa with normal morphology (r=0.73; P=0.04). Multiple regression equations indicated that combinations of semen quality measurements could be useful in estimating fertilizing potential.
Introduction Dairy farmers in the coastal areas of Oregon rely heavily on pastures for both grazi... more Introduction Dairy farmers in the coastal areas of Oregon rely heavily on pastures for both grazing and silage production. As managers, they ideally should be matching the nutrients supplied in the form of manure to their forage crops for maximum productivity, without over applying any one particular nutrient. Several studies have shown the timing of manure application is important in the uptake of nutrients from the soil. The more frequent applications increase nutrient removal and total crop yield. Perennial plants have also been shown more effective in removing nutrients when compared to annuals crops with similar requirements (Knezack and Miller, 1976; Hensler, 1970). Some of the more modern forage grasses have limited to no data on nutrient utilization. Moore and Gamroth (1995) showed some grass varieties in the Willamette Valley, Oregon, treated with 300lbs/N per acre in season removed over 400 lbs/N per acre in plant growth. In their study they also had a treatment of manure at 450-lbs/N per acre, with plant removal rates of nitrogen near 500 lbs/ N per acre. It was thought for years, forage grasses utilized only around 200 lbs up to 300 lbs /N acre for the highest producing grasses like orchard grasses. Most animal waste management plans written for pastured based dairies use estimates for manure produced and yields removed to design the waste plan. Landowners theoretically have been required to apply nitrogen (N) in quantities equal to what they remove annually in a crop. As concerns for water quality have increased, so has the need to demonstrate that the nutrients applied are equal to what is removed. Over the past year, a trial was conducted to develop a realistic plan for dairymen to document nutrient application and removal on pasture based dairies. This project was designed to be a model for documenting manure applications and forage removal in pasture-based dairies.
Well-preserved silage is characterized by reduced pH, greater lactic acid concentration, and redu... more Well-preserved silage is characterized by reduced pH, greater lactic acid concentration, and reduced ammonia (NH 3) concentration compared with silage that did not ferment well. Water soluble carbohydrates (WSC) are the primary fermentation substrate. In temperate grass forages, glucose, fructose, sucrose, and fructans are the primary WSC. New varieties of ryegrass have been developed in the United Kingdom to express high levels of WSC. The objective of this trial was to determine differences in fermentation characteristics of grasses with different WSC levels cut and processed as silage. Four perennial ryegrasses, 3 cultivars with a relatively greater WSC concentration (AberAvon, AberDart, and Elgon) and 1 cultivar commonly grown in Oregon, the control WSC (Linn), were planted. Three replicates of each grass were ensiled after morning and afternoon harvests. Each sample was packed, vacuum sealed, and ensiled for 60 d at 10°C. Fresh grass samples were taken from each cutting and analyzed before ensiling. Fresh grass WSC was greater in the 3 high WSC grass cultivars vs. Linn.
Dairy farmers use footbaths to control diseases of the hoof. When the footbaths are changed, the ... more Dairy farmers use footbaths to control diseases of the hoof. When the footbaths are changed, the solutions are dumped into the dairy manure handling system and applied to fields in the liquid manure system. The objective for this project was to survey 30 dairy farms in Oregon to evaluate CuSO 4 and ZnSO 4 use in footbaths. Soil samples were collected from 2 major fields at 15 cm deep and all samples were analyzed for Cu and Zn. Forages grown on the farm were sampled and analyzed for Cu and Zn, and manure was collected directly from milk cows and from the liquid manure storage system. All forages, soils, and manure were analyzed for Cu and Zn. Soil Cu concentrations ranged from 0.7 to 34.7 ppm, with an average of 5.7 ± 6.6 ppm. Soil Zn concentrations ranged from 0.6 to 41.8 ppm, with an average of 10.1 ± 9.3 ppm. Forage Cu concentrations ranged from 1 to 10 ppm, with an average of 3.4 ± 2.1 ppm, and forage Zn ranged from 3 to 51 ppm, with an average of 13.8 ± 10.3 ppm. Copper concentrations in fresh manure directly from milking cows were very consistent, at 10 ppm, and Cu in the manure storage ranged from 2 to 58 ppm, with an average of 10.3 ± 12 ppm. The use of CuSO 4 and ZnSO 4 in footbaths on dairies in Oregon continues to be a common practice. More than 75% of dairy soils tested were considered high (>2 ppm) in Cu concentration and 38% were extremely high (>5 ppm). Using CuSO 4 and ZnSO 4 in footbaths is creating potential long-term environmental and cropping challenges on many Oregon dairies.
Published July 2006. Reviewed March 2016. Please look for up-to-date information in the OSU Exten... more Published July 2006. Reviewed March 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published June 2007. Reviewed December 2014. Facts and recommendations in this publication may no... more Published June 2007. Reviewed December 2014. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Managing pastures on grazing dairies is a continuous challenge because pasture quality, quantity,... more Managing pastures on grazing dairies is a continuous challenge because pasture quality, quantity, and growth rate are changing daily. The objectives of this study were to document weekly pasture growth, forage quality, and performance to understand how to use this information to make management decisions on US dairies. One organic grazing dairy was studied for 3 consecutive years. Pastures were measured and mapped, and total standing DM was estimated weekly in all 22 pastures using a calibrated rising plate meter. Weekly grazing wedges were developed and were used to make grazing decisions that week. Paddocks grazed and residual pasture covers were recorded daily. Paddock grazing and residual heights were also included in the electronic recordkeeping. Dry matter yields ranged from 11,277 to 22,346 kg/ha per year and averaged 15,887 ± 1,919, 17,848 ± 1,966 and 17,956 ± 2,014 for each consecutive year. Daily growth rates ranged from 18 to 100 kg/ha per day throughout the season and averaged as high as 56 ± 20.3 kg/ha per day in yr 3. Pasture quality and productivity in Oregon is comparable to some of the most productive dairy pasture systems reported from around the world.
Dairy nutritionists have long known that forages with the same laboratory analysis could produce ... more Dairy nutritionists have long known that forages with the same laboratory analysis could produce significantly different performance in lactating cows. Neutral detergent fiber digestibility (NDFD) may explain much of this variation. The objectives of the study described here were to demonstrate NDFD variation between varieties of ryegrass and season of harvest and to use this information as the basis for an educational Extension program. Large differences in NDFD were found among 11 varieties of ryegrass. This information was used to change the way livestock rations are balanced and it is hoped will convince grass seeds companies to focus more on fiber digestibility.
Journal of Histochemistry & Cytochemistry, 1991
Several fluorescent probes, including derivatives of carboxyfluorescein, carbocyanine, ethidium, ... more Several fluorescent probes, including derivatives of carboxyfluorescein, carbocyanine, ethidium, and rhodamine, have been used to assess sperm viability. However, the effects of these fluorescent dyes on the metabolic activity of sperm cells have not been systematically examined. This study was conducted to determine the effect of specific fluorescent stains on the metabolic processes of sperm. Cryopreserved bovine sperm cells were thawed, fluorescently stained, and examined using metabolic and flow cytometric techniques. Sperm were stained with either rhodamine 123 (Rhod-123), the aliphatic cell-tracking compound PKH2-GL, dihydro-ethidium (HED), the bisbenzimide stain Hoechst 33342 (Ho33342), or left unstained. The stained samples were compared for metabolic activity, cell staining pattern, and fluorescent intensity over a 180-min period. Samples stained with HED, Ho33342, and PKH2-GL had less oxygen uptake when compared with the unstained sperm samples (p greater than 0.05). Unsta...
High-quality forages, such as alfalfa and grasses, are important for efficient milk production fr... more High-quality forages, such as alfalfa and grasses, are important for efficient milk production from dairy cows. Forages provide the effective fiber that is critical for good health and longevity. Inadequate effective fiber in the cow's diet is one reason for acidosis and milk fat ...
Increasing pasture diversity and spatially separated sowing arrangements can potentially increase... more Increasing pasture diversity and spatially separated sowing arrangements can potentially increase the dry matter intake of high-quality forages leading to improved animal production. This study investigated the effects of simple (two-species) and diverse (six-species) pastures planted either in mixed or spatially separated adjacent pasture strips on performance, N partitioning, and methane emission of dairy cows. Thirty-six mid-lactation Jersey cows grazed either (1) simple mixed, (2) simple spatially separated, (3) diverse mixed, or (4) diverse spatially separated pastures planted in a complete randomized block design with three replicates. Compared to simple pasture, diverse pasture had lower CP content but higher condensed tannins and total phenolic compounds with an overall positive effect on yield of milk solids, nitrogen utilization, including a reduction of N output from urine, and methane yields per dry matter eaten. The spatial separation increased legume and CP content in ...
Whether your goal is to manage manure application to balance for nitrogen or for phosphorus, know... more Whether your goal is to manage manure application to balance for nitrogen or for phosphorus, knowing how much nutrient you are applying is a crucial step toward ideal manure management. Determining the relationship between volume of waste and the amount of nutrients applied is essential. This publication describes how to calibrate waste-handling equipment and to calculate nutrient application rates. It covers typical equipment found on dairies and uses nitrogen in the examples. The same techniques can be used with phosphorus. Generally, it is desirable to apply no more than 100 pounds N per acre at a time. See the publications listed under "For more information" on page 6 to learn how to determine appropriate nutrient application rates for your situation.
Revised April 2004. Revised December 2014. Please look for up-to-date information in the OSU Exte... more Revised April 2004. Revised December 2014. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
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