The objectives of this study were to determine the difficulty of implementing changes to improve ... more The objectives of this study were to determine the difficulty of implementing changes to improve cow comfort on Canadian dairy farms, to determine if any changes were implemented to improve dairy cow comfort following an initial cow comfort assessment, to categorize producers based on types of changes they made, to compare how producers in these categories differed, and to identify barriers to implementing these changes. The most difficult type of change to implement was changing stall design (including building a new barn) with a mean difficulty score of 3.3 (out of 5) scored by a panel of dairy researchers. Overall, 3 of 118 (2.5%) interviewed producers were categorized as innovators, 62 (52.5%) as effective adopters, 20 (16.9%) as ineffective adopters, and 33 (28.0%) as non-adopters. The most common types of changes made were to stall management (37.3%). Participants were asked to identify all barriers to further improvement of cow comfort. The most commonly reported barriers wer...
The standing and lying behavior patterns of dairy cows, particularly the length of time cows spen... more The standing and lying behavior patterns of dairy cows, particularly the length of time cows spend standing after milking, have the potential to influence the incidence of intramammary infection (IMI). The objectives were to describe the standing and lying behavior patterns of cows milked with an automatic milking system (AMS) and to determine how these patterns relate to the incidence of IMI. One hundred and eleven lactating Holstein dairy cows were monitored over a 4-mo period. These cows were kept in a sand-bedded freestall barn with 2 pens, each with a free cow traffic AMS. Feed was delivered once daily, and pushed up 2 to 3 times daily. Quarter milk samples were collected for bacteriological culture from each cow once every 4 wk. A new IMI was defined as a positive culture sample following a negative culture. For 7 d before each of the last 3 milk samplings, standing and lying behavior, and times of milking and feed manipulation (feed delivery and push up) were recorded. Daily ...
The challenges associated with group-housed dairy cows include within-herd variability in nutrien... more The challenges associated with group-housed dairy cows include within-herd variability in nutrient consumption and milk production, which may be related to feeding management. The objective of this observational study was to examine the association of herd-level feeding management factors, feed sorting, and milk production. Twenty-two freestall herds with an average lactating herd size of 162±118 cows, feeding total mixed rations, were each studied for 7 consecutive days in summer and winter. In cases of multiple feeding groups within a herd, the highest producing group of cows with an even distribution of days in milk and parity was selected for this study. The average group size studied was 83±31 cows. The average study group consisted of cows 187±47 days in milk, with a parity of 2.3±0.6, consuming 24.3±2.6kg of dry matter, with an average group-level yield of 34.3±6kg of milk/d, 3.7±0.3% milk fat, and 3.2±0.18% milk protein. Milk production parameters, including yield, fat, and ...
Dairy producers are continually challenged with ensuring adequate, consistent, and balanced nutri... more Dairy producers are continually challenged with ensuring adequate, consistent, and balanced nutrient intake in their cows to ensure good health and productivity of the cows and efficiency of production. Total mixed ration (TMR) feeding systems are widely recognized as the optimal way to maximize intake and provide the consistent balance of nutrients that dairy cattle need. In theory, TMR are formulated so that producers are confident they are providing their dairy cattle a well-balanced diet that is consumed to meet production requirements. Unfortunately, the full potential of the formulated TMR is not always reached on every farm. We need to consider if cows have access to the right TMR and if they consume that ration in a good manner. Only then can we design feeding systems to allow cows to optimize the use of those rations.
Producers report bovine respiratory disease (BRD) and diarrhea as the 2 most common diseases in p... more Producers report bovine respiratory disease (BRD) and diarrhea as the 2 most common diseases in preweaned calves, both of which can affect calf performance and welfare. Group housing has the potential to improve calf welfare, but only if producers are able to detect disease. To reduce time evaluating individual calves, there is a need for a group level healthscreening tool to identify potentially sick calves that require further examination. The objective of this study was to develop a screening tool using behavioral measures to detect disease in preweaned grouphoused dairy calves. This cross-sectional study included the evaluation of preweaned group-housed calves (n = 206) on 4 farms in Wisconsin. Calves were scored for behaviors that were hypothesized to be indicative of illness: abnormal posture when lying or standing, isolation, lethargy, and the willingness to approach a stationary person (2 approach tests were performed and each was scored separately). Each behavior category w...
Knowledge of canine food selection is critical for both the pet food industry and dog owners, sin... more Knowledge of canine food selection is critical for both the pet food industry and dog owners, since owners want quality foods that are palatable, while fulfilling their pet's nutritional requirements. There are two common methods for assessing canine food preference: the two-pan test and the one-pan test. Neither test fully accounts for the complexity of the canine feeding experience nor do they provide applicable representations of canine feeding behavior in the home. The objectives of this study were to (1) determine whether dogs display a preference for animal ingredient-based diets when compared with vegetable ingredient-based diets and (2) examine whether dogs experience neophobia when presented with a novel diet. Eight adult Beagles (average age = 24 months, weighing 8-12 kg) were individually fed each of four novel diets in a 4 × 4 replicated Latin square design, with 10-d treatment periods and four dietary treatments. Data were analyzed using a mixed model with repeated ...
Dairy calves in North America traditionally are housed individually and fed by manual milk feedin... more Dairy calves in North America traditionally are housed individually and fed by manual milk feeding (MMF) systems with buckets or bottles. Automated milk feeders (AMF) allow for more natural milk feeding frequencies and volumes, and calves are usually housed in groups. The objectives of this study were to (1) determine the prevalence of various milk-fed calf management and feeding practices and (2) compare these practices between dairy farms using MMF and AMF systems. A national online survey was performed from January to May 2015 to quantify management practices for the care of milk-fed dairy calves in Canada. A total of 670 responses were received (6% of all dairy farms in Canada). Among respondents, 16% used AMF and 84% used MMF. Seventy percent of the farms using AMF had freestall barns compared with only 48% of those using MMF. A greater proportion of AMF farms (30%) also had automatic milking systems (AMS) compared with MMF farms (8%). Among tiestall farms, a herd size of >8...
An observational study of 790 to over 3,000 herds was conducted to estimate the within-herd preva... more An observational study of 790 to over 3,000 herds was conducted to estimate the within-herd prevalence and cow-level risk factors for ketosis in dairy cattle in herds that participate in a Dairy Herd Improvement Association (DHIA) program. Ketosis or hyperketolactia (KET) was diagnosed as milk β-hydroxybutyrate ≥0.15 mmol/L at first DHIA test when tested within the first 30 d in milk. Seven hundred ninety-five herds providing at least 61 first milk tests from June 2014 to December 2015 were used to estimate the provincial within-herd prevalence of KET. All herds on DHIA in Ontario (n = 3,042) were used to construct cow-level multilevel logistic regression models to investigate the association of DHIA collected variables with the odds of KET at first DHIA milk test. Primiparous and multiparous animals were modeled independently. The cow-level KET prevalence in Ontario was 21%, with an average within-herd prevalence of 21% (standard deviation = 10.6) for dairy herds enrolled in a DHIA...
The objective of this study was to examine the behavioral and growth responses of dairy heifers w... more The objective of this study was to examine the behavioral and growth responses of dairy heifers when a low-nutritive feedstuff was provided with (either within or alongside) a limit-fed ration. Twenty-four Holstein dairy heifers (187 ± 11.3 d of age, 231.1 ± 12.0kg), divided in groups of 4, were exposed to each of 3 treatments in a replicated Latin square design with 28-d periods. The treatment rations were (1) total mixed ration (TMR) in a limited amount (TMR-L), (2) TMR in a limited amount with straw (1.8 kg of DM/d per heifer) offered as a choice (TMR-SC), and (3) TMR in a limited amount with straw (1.8 kg of DM/d per heifer) mixed in (TMR-SM). The TMR was fed, once daily, at a restricted level (2.02% of body weight) and contained (on a DM basis) 19.0% alfalfa/grass haylage, 21% corn silage, 45% high moisture corn, and 15% protein supplement. Feeding behavior and unrewarded time at the feed bunk were recorded for the last 14 d of each period. Standing time was recorded for the la...
The objective of this study was to determine whether addition of water to a high-moisture total m... more The objective of this study was to determine whether addition of water to a high-moisture total mixed ration reduces feed sorting by dairy cattle. Twelve lactating Holstein cows, individually fed once per day, were tested on 2 diets in a crossover design with 21-d periods. Diets had the same dietary composition and differed only in dry matter content, which was reduced by the addition of water. Treatment diets were 1) dry (57.6% DM) and 2) wet (47.9% DM). Dry matter intake (DMI) and milk production were monitored for each animal for the last 7 d of both treatment periods. For the final 3 d of each period, milk samples were taken for composition analysis and fresh feed and orts were sampled for particle size analysis. The particle size separator had 3 screens (19, 8, and 1.18 mm) and a bottom pan, resulting in 4 fractions (long, medium, short, fine). Sorting was calculated as the actual intake of each particle size fraction expressed as a percentage of the predicted intake of that fr...
The objective of this study was to determine if the feeding behavior of dairy cows is modified th... more The objective of this study was to determine if the feeding behavior of dairy cows is modified through live yeast supplementation. Twelve lactating Holstein dairy cows (2 primiparous and 10 multiparous) were individually exposed, in a replicated crossover design, to each of 2 treatment diets (over 35-d periods): (1) a control TMR and (2) a control TMR plus 1 × 10(10) cfu/head per day of live yeast (Saccharomyces cerevisiae CNCM I-1077; Levucell SC20; Lallemand Animal Nutrition, Montreal, QC, Canada). Milk production, feeding, and rumination behavior were electronically monitored for each animal for the last 7 d of each treatment period. Milk samples were collected for the last 6 d of each period for milk component analysis. Dry matter intake (28.3 kg/d), eating time (229.3 min/d), and rate (0.14 kg of dry matter/min) were similar between treatments. With yeast supplementation, meal criteria (minimum intermeal interval) were shorter (20.0 vs. 25.8 min), translating to cows tending to...
Concurrent data on antimicrobial use (AMU) and resistance are needed to contain antimicrobial res... more Concurrent data on antimicrobial use (AMU) and resistance are needed to contain antimicrobial resistance (AMR) in bacteria. The present study examined a herd-level association between AMU and AMR in Escherichia coli (n=394) and Klebsiella species (n=139) isolated from bovine intramammary infections and mastitis cases on 89 dairy farms in 4 regions of Canada [Alberta, Ontario, Québec, and Maritime Provinces (Prince Edward Island, Nova Scotia, and New Brunswick)]. Antimicrobial use data were collected using inventory of empty antimicrobial containers and antimicrobial drug use rate was calculated to quantify herd-level AMU. Minimum inhibitory concentrations (MIC) were determined using Sensititre National Antimicrobial Resistance Monitoring System (NARMS) gram-negative MIC plate (Trek Diagnostic Systems Inc., Cleveland, OH). Isolates were classified as susceptible, intermediate, or resistant. Intermediate and resistant category isolates were combined to form an AMR category, and multiv...
Feed sorting of dairy cattle is influenced by dietary forage particle size. The objective of this... more Feed sorting of dairy cattle is influenced by dietary forage particle size. The objective of this study was to determine the effect of early exposure to rations differing in forage particle size on development of feed sorting in dairy calves. Twenty Holstein bull calves were exposed for 8 wk to 1 of 2 mixed rations containing (on a dry-matter basis) 90% crumb starter concentrate and either (1) 10% coarsely chopped (3- to 4-cm) grass hay (CRS; n=10) or (2) 10% finely ground (2-mm) grass hay (FN; n=10), both offered ad libitum. Calves received 8L of milk replacer/d (1.2 kg of dry matter/d), with the amount progressively reduced after 5 wk, to facilitate weaning by the end of wk 7. At the beginning of wk 9, all calves received the CRS diet and were followed for 3 wk. Intake was recorded daily and calves were weighed twice per week. Samples of fresh feed and orts were taken on d 1 to 4 of wk 9 and 11 for analysis of feed sorting. Sorting of the ration was assessed through analysis of nu...
Time sampling techniques are useful in collecting feeding behavior data because they minimize the... more Time sampling techniques are useful in collecting feeding behavior data because they minimize the time required for observation. Instantaneous recording is often used in the collection of feeding behavior data for dairy calves; however, the recording intervals used vary widely and it is unclear what minimum interval is necessary to yield accurate data. The objective of this study was to validate data obtained using instantaneous recording of feeding behavior of dairy calves across a range of time intervals with data obtained from continuous recording. Ten Holstein bull calves were observed continuously using time-lapse video for 3 d during the milk-feeding period while they were fed milk ad libitum and for 3 d post-milk-weaning while they consumed solid feed. Feeding behavior data obtained from continuous recording were compared with data obtained from instantaneous recording at intervals ranging from 15 s to 10 min. As expected, the strength of linear association between behavior m...
The objective of this study was to determine the effects of water addition to a high-moisture tot... more The objective of this study was to determine the effects of water addition to a high-moisture total mixed ration (TMR) on feed temperature, feed intake, feed sorting behavior, and milk production of dairy cows. Twelve lactating Holstein cows (155.8+/-60.1 DIM), individually fed once daily at 1000 h, were exposed to 3 diets in a Latin square design with 28-d treatment periods. Diets had the same ingredient composition [30.9% corn silage, 30.3% alfalfa haylage, 21.2% high-moisture corn, and 17.6% protein supplement; dry matter (DM) basis] and differed only in DM concentration, which was reduced by the addition of water. Treatment diets averaged 56.3, 50.8, and 44.1% DM. The study was conducted between May and August when environmental temperature was 18.2+/-3.6 degrees C and ambient temperature in the barn was 24.4+/-3.3 degrees C. Dry matter intake (DMI) was monitored for each animal for the last 14 d of each treatment period. For the final 7 d of each period, milk production was mon...
The objectives of this study were to determine the difficulty of implementing changes to improve ... more The objectives of this study were to determine the difficulty of implementing changes to improve cow comfort on Canadian dairy farms, to determine if any changes were implemented to improve dairy cow comfort following an initial cow comfort assessment, to categorize producers based on types of changes they made, to compare how producers in these categories differed, and to identify barriers to implementing these changes. The most difficult type of change to implement was changing stall design (including building a new barn) with a mean difficulty score of 3.3 (out of 5) scored by a panel of dairy researchers. Overall, 3 of 118 (2.5%) interviewed producers were categorized as innovators, 62 (52.5%) as effective adopters, 20 (16.9%) as ineffective adopters, and 33 (28.0%) as non-adopters. The most common types of changes made were to stall management (37.3%). Participants were asked to identify all barriers to further improvement of cow comfort. The most commonly reported barriers wer...
The standing and lying behavior patterns of dairy cows, particularly the length of time cows spen... more The standing and lying behavior patterns of dairy cows, particularly the length of time cows spend standing after milking, have the potential to influence the incidence of intramammary infection (IMI). The objectives were to describe the standing and lying behavior patterns of cows milked with an automatic milking system (AMS) and to determine how these patterns relate to the incidence of IMI. One hundred and eleven lactating Holstein dairy cows were monitored over a 4-mo period. These cows were kept in a sand-bedded freestall barn with 2 pens, each with a free cow traffic AMS. Feed was delivered once daily, and pushed up 2 to 3 times daily. Quarter milk samples were collected for bacteriological culture from each cow once every 4 wk. A new IMI was defined as a positive culture sample following a negative culture. For 7 d before each of the last 3 milk samplings, standing and lying behavior, and times of milking and feed manipulation (feed delivery and push up) were recorded. Daily ...
The challenges associated with group-housed dairy cows include within-herd variability in nutrien... more The challenges associated with group-housed dairy cows include within-herd variability in nutrient consumption and milk production, which may be related to feeding management. The objective of this observational study was to examine the association of herd-level feeding management factors, feed sorting, and milk production. Twenty-two freestall herds with an average lactating herd size of 162±118 cows, feeding total mixed rations, were each studied for 7 consecutive days in summer and winter. In cases of multiple feeding groups within a herd, the highest producing group of cows with an even distribution of days in milk and parity was selected for this study. The average group size studied was 83±31 cows. The average study group consisted of cows 187±47 days in milk, with a parity of 2.3±0.6, consuming 24.3±2.6kg of dry matter, with an average group-level yield of 34.3±6kg of milk/d, 3.7±0.3% milk fat, and 3.2±0.18% milk protein. Milk production parameters, including yield, fat, and ...
Dairy producers are continually challenged with ensuring adequate, consistent, and balanced nutri... more Dairy producers are continually challenged with ensuring adequate, consistent, and balanced nutrient intake in their cows to ensure good health and productivity of the cows and efficiency of production. Total mixed ration (TMR) feeding systems are widely recognized as the optimal way to maximize intake and provide the consistent balance of nutrients that dairy cattle need. In theory, TMR are formulated so that producers are confident they are providing their dairy cattle a well-balanced diet that is consumed to meet production requirements. Unfortunately, the full potential of the formulated TMR is not always reached on every farm. We need to consider if cows have access to the right TMR and if they consume that ration in a good manner. Only then can we design feeding systems to allow cows to optimize the use of those rations.
Producers report bovine respiratory disease (BRD) and diarrhea as the 2 most common diseases in p... more Producers report bovine respiratory disease (BRD) and diarrhea as the 2 most common diseases in preweaned calves, both of which can affect calf performance and welfare. Group housing has the potential to improve calf welfare, but only if producers are able to detect disease. To reduce time evaluating individual calves, there is a need for a group level healthscreening tool to identify potentially sick calves that require further examination. The objective of this study was to develop a screening tool using behavioral measures to detect disease in preweaned grouphoused dairy calves. This cross-sectional study included the evaluation of preweaned group-housed calves (n = 206) on 4 farms in Wisconsin. Calves were scored for behaviors that were hypothesized to be indicative of illness: abnormal posture when lying or standing, isolation, lethargy, and the willingness to approach a stationary person (2 approach tests were performed and each was scored separately). Each behavior category w...
Knowledge of canine food selection is critical for both the pet food industry and dog owners, sin... more Knowledge of canine food selection is critical for both the pet food industry and dog owners, since owners want quality foods that are palatable, while fulfilling their pet's nutritional requirements. There are two common methods for assessing canine food preference: the two-pan test and the one-pan test. Neither test fully accounts for the complexity of the canine feeding experience nor do they provide applicable representations of canine feeding behavior in the home. The objectives of this study were to (1) determine whether dogs display a preference for animal ingredient-based diets when compared with vegetable ingredient-based diets and (2) examine whether dogs experience neophobia when presented with a novel diet. Eight adult Beagles (average age = 24 months, weighing 8-12 kg) were individually fed each of four novel diets in a 4 × 4 replicated Latin square design, with 10-d treatment periods and four dietary treatments. Data were analyzed using a mixed model with repeated ...
Dairy calves in North America traditionally are housed individually and fed by manual milk feedin... more Dairy calves in North America traditionally are housed individually and fed by manual milk feeding (MMF) systems with buckets or bottles. Automated milk feeders (AMF) allow for more natural milk feeding frequencies and volumes, and calves are usually housed in groups. The objectives of this study were to (1) determine the prevalence of various milk-fed calf management and feeding practices and (2) compare these practices between dairy farms using MMF and AMF systems. A national online survey was performed from January to May 2015 to quantify management practices for the care of milk-fed dairy calves in Canada. A total of 670 responses were received (6% of all dairy farms in Canada). Among respondents, 16% used AMF and 84% used MMF. Seventy percent of the farms using AMF had freestall barns compared with only 48% of those using MMF. A greater proportion of AMF farms (30%) also had automatic milking systems (AMS) compared with MMF farms (8%). Among tiestall farms, a herd size of >8...
An observational study of 790 to over 3,000 herds was conducted to estimate the within-herd preva... more An observational study of 790 to over 3,000 herds was conducted to estimate the within-herd prevalence and cow-level risk factors for ketosis in dairy cattle in herds that participate in a Dairy Herd Improvement Association (DHIA) program. Ketosis or hyperketolactia (KET) was diagnosed as milk β-hydroxybutyrate ≥0.15 mmol/L at first DHIA test when tested within the first 30 d in milk. Seven hundred ninety-five herds providing at least 61 first milk tests from June 2014 to December 2015 were used to estimate the provincial within-herd prevalence of KET. All herds on DHIA in Ontario (n = 3,042) were used to construct cow-level multilevel logistic regression models to investigate the association of DHIA collected variables with the odds of KET at first DHIA milk test. Primiparous and multiparous animals were modeled independently. The cow-level KET prevalence in Ontario was 21%, with an average within-herd prevalence of 21% (standard deviation = 10.6) for dairy herds enrolled in a DHIA...
The objective of this study was to examine the behavioral and growth responses of dairy heifers w... more The objective of this study was to examine the behavioral and growth responses of dairy heifers when a low-nutritive feedstuff was provided with (either within or alongside) a limit-fed ration. Twenty-four Holstein dairy heifers (187 ± 11.3 d of age, 231.1 ± 12.0kg), divided in groups of 4, were exposed to each of 3 treatments in a replicated Latin square design with 28-d periods. The treatment rations were (1) total mixed ration (TMR) in a limited amount (TMR-L), (2) TMR in a limited amount with straw (1.8 kg of DM/d per heifer) offered as a choice (TMR-SC), and (3) TMR in a limited amount with straw (1.8 kg of DM/d per heifer) mixed in (TMR-SM). The TMR was fed, once daily, at a restricted level (2.02% of body weight) and contained (on a DM basis) 19.0% alfalfa/grass haylage, 21% corn silage, 45% high moisture corn, and 15% protein supplement. Feeding behavior and unrewarded time at the feed bunk were recorded for the last 14 d of each period. Standing time was recorded for the la...
The objective of this study was to determine whether addition of water to a high-moisture total m... more The objective of this study was to determine whether addition of water to a high-moisture total mixed ration reduces feed sorting by dairy cattle. Twelve lactating Holstein cows, individually fed once per day, were tested on 2 diets in a crossover design with 21-d periods. Diets had the same dietary composition and differed only in dry matter content, which was reduced by the addition of water. Treatment diets were 1) dry (57.6% DM) and 2) wet (47.9% DM). Dry matter intake (DMI) and milk production were monitored for each animal for the last 7 d of both treatment periods. For the final 3 d of each period, milk samples were taken for composition analysis and fresh feed and orts were sampled for particle size analysis. The particle size separator had 3 screens (19, 8, and 1.18 mm) and a bottom pan, resulting in 4 fractions (long, medium, short, fine). Sorting was calculated as the actual intake of each particle size fraction expressed as a percentage of the predicted intake of that fr...
The objective of this study was to determine if the feeding behavior of dairy cows is modified th... more The objective of this study was to determine if the feeding behavior of dairy cows is modified through live yeast supplementation. Twelve lactating Holstein dairy cows (2 primiparous and 10 multiparous) were individually exposed, in a replicated crossover design, to each of 2 treatment diets (over 35-d periods): (1) a control TMR and (2) a control TMR plus 1 × 10(10) cfu/head per day of live yeast (Saccharomyces cerevisiae CNCM I-1077; Levucell SC20; Lallemand Animal Nutrition, Montreal, QC, Canada). Milk production, feeding, and rumination behavior were electronically monitored for each animal for the last 7 d of each treatment period. Milk samples were collected for the last 6 d of each period for milk component analysis. Dry matter intake (28.3 kg/d), eating time (229.3 min/d), and rate (0.14 kg of dry matter/min) were similar between treatments. With yeast supplementation, meal criteria (minimum intermeal interval) were shorter (20.0 vs. 25.8 min), translating to cows tending to...
Concurrent data on antimicrobial use (AMU) and resistance are needed to contain antimicrobial res... more Concurrent data on antimicrobial use (AMU) and resistance are needed to contain antimicrobial resistance (AMR) in bacteria. The present study examined a herd-level association between AMU and AMR in Escherichia coli (n=394) and Klebsiella species (n=139) isolated from bovine intramammary infections and mastitis cases on 89 dairy farms in 4 regions of Canada [Alberta, Ontario, Québec, and Maritime Provinces (Prince Edward Island, Nova Scotia, and New Brunswick)]. Antimicrobial use data were collected using inventory of empty antimicrobial containers and antimicrobial drug use rate was calculated to quantify herd-level AMU. Minimum inhibitory concentrations (MIC) were determined using Sensititre National Antimicrobial Resistance Monitoring System (NARMS) gram-negative MIC plate (Trek Diagnostic Systems Inc., Cleveland, OH). Isolates were classified as susceptible, intermediate, or resistant. Intermediate and resistant category isolates were combined to form an AMR category, and multiv...
Feed sorting of dairy cattle is influenced by dietary forage particle size. The objective of this... more Feed sorting of dairy cattle is influenced by dietary forage particle size. The objective of this study was to determine the effect of early exposure to rations differing in forage particle size on development of feed sorting in dairy calves. Twenty Holstein bull calves were exposed for 8 wk to 1 of 2 mixed rations containing (on a dry-matter basis) 90% crumb starter concentrate and either (1) 10% coarsely chopped (3- to 4-cm) grass hay (CRS; n=10) or (2) 10% finely ground (2-mm) grass hay (FN; n=10), both offered ad libitum. Calves received 8L of milk replacer/d (1.2 kg of dry matter/d), with the amount progressively reduced after 5 wk, to facilitate weaning by the end of wk 7. At the beginning of wk 9, all calves received the CRS diet and were followed for 3 wk. Intake was recorded daily and calves were weighed twice per week. Samples of fresh feed and orts were taken on d 1 to 4 of wk 9 and 11 for analysis of feed sorting. Sorting of the ration was assessed through analysis of nu...
Time sampling techniques are useful in collecting feeding behavior data because they minimize the... more Time sampling techniques are useful in collecting feeding behavior data because they minimize the time required for observation. Instantaneous recording is often used in the collection of feeding behavior data for dairy calves; however, the recording intervals used vary widely and it is unclear what minimum interval is necessary to yield accurate data. The objective of this study was to validate data obtained using instantaneous recording of feeding behavior of dairy calves across a range of time intervals with data obtained from continuous recording. Ten Holstein bull calves were observed continuously using time-lapse video for 3 d during the milk-feeding period while they were fed milk ad libitum and for 3 d post-milk-weaning while they consumed solid feed. Feeding behavior data obtained from continuous recording were compared with data obtained from instantaneous recording at intervals ranging from 15 s to 10 min. As expected, the strength of linear association between behavior m...
The objective of this study was to determine the effects of water addition to a high-moisture tot... more The objective of this study was to determine the effects of water addition to a high-moisture total mixed ration (TMR) on feed temperature, feed intake, feed sorting behavior, and milk production of dairy cows. Twelve lactating Holstein cows (155.8+/-60.1 DIM), individually fed once daily at 1000 h, were exposed to 3 diets in a Latin square design with 28-d treatment periods. Diets had the same ingredient composition [30.9% corn silage, 30.3% alfalfa haylage, 21.2% high-moisture corn, and 17.6% protein supplement; dry matter (DM) basis] and differed only in DM concentration, which was reduced by the addition of water. Treatment diets averaged 56.3, 50.8, and 44.1% DM. The study was conducted between May and August when environmental temperature was 18.2+/-3.6 degrees C and ambient temperature in the barn was 24.4+/-3.3 degrees C. Dry matter intake (DMI) was monitored for each animal for the last 14 d of each treatment period. For the final 7 d of each period, milk production was mon...
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