Effects of bedding quality on lying behavior of dairy cows

Cows prefer to spend more time lying down in free stalls with more bedding, but no research to date has addressed the effects of bedding quality. Bedding in stalls often becomes wet either from exposure to the elements or from feces and urine. The aim of this study was to test the effect of wet bedding on stall preference and use. Four groups of 6 nonlactating Holstein cows were housed in free stalls bedded daily with approximately 0.1 m of fresh sawdust. Following a 5-d adaptation period, each group of cows was tested sequentially with access to stalls with either dry or wet sawdust bedding (86.4 ± 2.1 vs. 26.5 ± 2.1% dry matter), each for 2 d. These no-choice phases were followed by a 2-d free-choice phase during which cows had simultaneous access to stalls containing either wet or dry bedding. Stall usage was assessed by using 24-h video recordings scanned at 10-min intervals, and responses were analyzed by using a mixed model, with group (n = 4) as the observational unit. The minimum and maximum environmental temperatures during the experiment were 3.4 ± 2.2 and 6.8 ± 2.5°C, respectively. When cows had access only to stalls with wet bedding, they spent 8.8 ± 0.8 h/d lying down, which increased to 13.8 ± 0.8 h/d when stalls with dry bedding were provided. Cows spent more time standing with their front 2 hooves in the stall when provided with wet vs. dry bedding (92 ± 10 vs. 32 ± 10 min/d). During the free-choice phase, all cows spent more time lying down in the dry stalls, spending 12.5 ± 0.3 h/d in the dry stalls vs. 0.9 ± 0.3 h/ d in stalls with wet bedding. In conclusion, dairy cows show a clear preference for a dry lying surface, and they spend much more time standing outside the stall when only wet bedding is available.     

Effect of prepartum grouping strategy on displacements from the feed bunk and feeding behavior of dairy cows

The objective of the current study was to determine whether providing stable pen management affected displacements from the feed bunk and feeding behavior of prepartum dairy cows. Two hundred and twenty-four nonlactating Jersey primiparous and multiparous cows were enrolled in the study. The 2 treatments were all-in-all-out (AIAO; 44 cows were moved into the close-up prepartum pen as 1 group, with no additions during the 5-wk repetition) or traditional (TRD; with weekly entrance of new cows to maintain a pen density of 44 cows). Cows (253 ± 3 d of gestation) were balanced for parity and projected 305-d mature-equivalent milk yield and assigned randomly to either AIAO or TRD treatments. At enrollment, cows with a body condition score <2 or >4 (1–5 scale; 1 = emaciated and 5 = obese) or with a locomotion score >3 (1–5 scale; 1 = normal gait and 5 = severely lame) were not included. Displacements from the feed bunk were measured weekly for both treatments when TRD cows were moved into the close-up pen (d 0) and additionally on d 1, 2, 3, and 7 for 3 h after fresh feed delivery. A displacement rate was created to take into account differences in stocking density throughout the experiment. Displacement rate was calculated as the number of displacements divided by the number of cows in the pen at that time. Feeding behavior was measured using video 10-min scan sampling for 24-h periods at d 0, 1, 2, and 7. Displacements and feeding behavior were recorded for all 5 wk of each repetition. Treatment × week interactions were detected for number of displacements and displacement rate. The TRD treatment had more displacements from the feed bunk than AIAO in wk 1, 3, and 5, with no differences in wk 2 and 4. Similarly, the TRD treatment had a greater displacement rate than the AIAO treatment in wk 1 and 5, with a tendency in wk 3. No differences between the treatments were detected in wk 2 and 4. A treatment × week interaction existed for feeding time. Cows housed in the AIAO treatment had longer average feeding times in wk 2 with a tendency in wk 3, but spent 39 fewer minutes eating than those in the TRD treatment during the wk 1 of the study. Housing prepartum close-up cows with stable pen management reduced displacements from the feed bunk and altered average daily feeding times.     

Short communication: Flooring preferences of dairy cows at calving

The present study investigated the flooring preference during the 30 h before parturition in Holstein dairy cows housed individually in a maternity pen. Seventeen multiparous cows were moved, on average, 2 d before expected calving date into an individual maternity pen with 3 different flooring surfaces: 10 cm of sand, pebble-top rubber mats, or concrete flooring, each covered with 15 cm of straw. Calving location, lying time, and total time and number of lying bouts on each of the floor types were recorded during 2 periods: precalving (24 to 29 h before calving) and at calving (0 to 5 h before calving). Ten cows calved on sand, 6 on concrete, and 1 on the rubber mat. Lying bouts increased during the hours closest to calving, regardless of flooring. The number of lying bouts did not differ between flooring types precalving but cows had more lying bouts on sand and concrete compared with rubber at calving. Cows spent more time lying down on sand and concrete compared with rubber precalving, but lying times did not differ between treatments at calving. Cows that calved on sand spent more time lying on sand at calving compared with the other 2 flooring types. Cows that calved on concrete did not show a flooring preference at calving. These results indicate that rubber mats are the least preferred by dairy cows in the maternity pens, even when covered with a deep layer of straw.     

Time of feed delivery affects the feeding and lying patterns of dairy cows

The objective of this experiment was to determine whether it is the return from milking or delivery of fresh feed that has the greater effect on the daily patterns of feeding and lying behavior of dairy cattle. Forty-eight lactating Holstein cows were subjected to each of 2 treatments in a 2 x 2 cross-over design replicated over time. The treatments were 1) milking and feed delivery times coinciding and 2) feed delivery 6 h after milking. Cows were milked twice daily at 0500 and 1700 h. An electronic monitoring system was used to measure the time spent at the feed alley. Time-lapse video was used to quantify the lying time and incidence of aggressive displacements of the cows at the feed alley. Cows increased their total daily feeding time by 12.5% when fed 6 h after milking. This change was driven by an 82% increase in feeding time during the first hour immediately following the delivery of fresh feed and a 26% decrease in feeding time during the first hour after milking. The delivery of feed 6 h after milking did not change the daily lying time of the cows, but did decrease the latency to lie down after milking by 20 min. The reduction in feeding time after milking and decreased latency to lie down resulted in a tendency for less aggressive interactions at the feed alley after the cows returned from milking. These results indicate that the delivery of fresh feed has a greater impact on stimulating feeding behavior than does the return from milking and that changes in feeding management can affect both the feeding and lying behavior of dairy cows.     

Frequency of feed delivery affects the behavior of lactating dairy cows

The objectives of this study were to examine how frequency of feed delivery affects 1) the behavior of group-housed and group-fed dairy cows and 2) the extent of feed sorting. These objectives were tested in two experiments. In each experiment, 48 lactating Holstein cows, split into groups of 12, were subjected to each of 2 treatments (over 10-d periods) in a cross-over design. The treatments for the first experiment were 1) delivery of feed once per day (1×) and 2) delivery of feed twice per day (2×). Treatments for the second experiment were 1) delivery of feed 2× and 2) delivery of feed four times per day (4×). For the 1×, 2×, and 4× treatments, feed was pushed up 3, 2, and 0 times per day, respectively. For both experiments, cows had 0.6 m of feeding space; one cows was allowed per lying stall. Time-lapse video was used to quantify the feeding and lying behavior, as well as the aggressive behavior displayed at the feed bunk by the cows. Changes in NDF content of the TMR throughout the day were used to determine the extent of feed sorting by the cows. In both experiments, increased frequency of feed provision increased, as well as changed, the distribution of daily feeding time. The changes in distribution of feeding time resulted in cows having more equal access to feed throughout the day. Frequency of feed delivery had no effect on the daily lying time of the cows or the daily incidence of aggressive interactions at the feed bunk. However, subordinate cows were not displaced as frequently when fed more often. For all treatments, in both experiments, the NDF content of the TMR present in the feed bunk increased throughout the day, indicating that sorting of the feed had occurred. Further, the amount of sorting of the feed was reduced by increasing the frequency of feed delivery from 1× to 2×. These results indicate that frequent delivery of feed improves access to feed for all cows, particularly during peak feeding periods when fresh feed is provided, and reduces the amount of feed sorting.     

Overstocking reduces lying time in dairy cows

Our objective was to understand the effect of overstocking on the lying and standing behavior of dairy cattle. We manipulated freestall availability by providing 12, 11, 10, 9, or 8 freestalls to 12 cows (n = 4 groups, 12 cows/group), thus creating stocking levels of 100, 109, 120, 133, and 150%, respectively. Treatments were applied for a week at a time in a switchback design. Each group returned to the 100% stocking level after exposure to the other treatments. In addition to lying and standing behavior, we measured each cow's ability to displace others from the freestall to understand the interaction between social status and response to overstocking. When groups of cows had fewer stalls available, they spent less time lying down. There was no effect of overstocking on time spent standing with only the front legs in the stall. Instead, cows compensated for the reduced lying times by spending more time outside of the stall. When fewer stalls were available, animals were more likely to be displaced from stalls. The cow's ability to displace others from the stalls, however, did not explain the magnitude of their reduction in lying time when provided with fewer freestalls. Due to increased competition for stalls, cows lay down sooner at 150% than at the 100% level. Stall use was more uniform across time and across stalls within the pen when fewer freestalls were available. In conclusion, when cows had access to fewer freestalls, there was increased competition for stalls, increased time standing outside the stalls, and reduced lying time.     

The effects of feed bunk competition on the feed sorting behavior of close-up dry cows

The objectives of this research were to describe the feed sorting, feeding behavior, and feed intake of cows consuming a close-up ration and to determine if these behaviors are affected by competition for access to the feed bunk. Thirty-six dry Holstein cows, consuming a close-up total mixed ration diet, were assigned to 1 of 2 treatments: 1) noncompetitive (1 cow/feed bin) or 2) competitive (2 cows/feed bin). Dry matter intake, feeding behavior, and sorting behavior were monitored for each feed bin on 4 separate days during wk 2 and 3 before the anticipated calving dates of the cows. Fresh feed and orts were sampled daily from each bin and were subjected to particle size analysis. The particle size separator consisted of 3 screens (18, 9, and 1.18 mm) and a bottom pan resulting in 4 fractions (long, medium, short, and fine). Sorting was calculated as the actual intake of each particle size fraction expressed as a percentage of the predicted intake of that fraction. Regardless of treatment, the cows sorted against long particles and for short and fine particles. Competition at the feed bunk had no effect on the sorting behavior, dry matter intake, or feeding time of the cows, but did dramatically increase the feeding rate of the cows. The competitively fed cows also had fewer meals per day, and tended to have larger and longer meals. Our results suggest that increased competition at the feed bunk promotes feeding behavior patterns that will likely increase the between-cow variation in composition of total mixed ration consumed.     

Refinement of international recommendations for cubicles,based on the identification of associations between cubicle characteristics and dairy cow welfare measures

Maladjusted cubicles for dairy cattle may cause increased skin alterations, lameness, and dirtiness. The International Commission of Agricultural and Biosystems Engineering has produced several recommendations for cubicle design, but a previous study showed that not all of them seem efficient. Here, we aim to refine and complete these recommendations. We collected data on 76 dairy farms (2,404 cows). We modeled the association between combinations of cubicle properties (e.g., type of bedding litter) and dimensions (e.g., cubicle width) relative to cow size, and prevalence of cow skin alterations, lameness, and dirtiness. We used weighted multivariable logistic regression models to predict the presence of skin alteration on the carpus; the neck, shoulder, and back; the flank, side, and udder; and the tarsus or hindquarters. We also evaluated the presence of lameness as well as the dirtiness of the lower hind legs including hocks; the hindquarters, upper hind legs, and flank; the cow rear including tail; and the udder. The risk factors highlighted led us to recommend (1) position cubicles in a way that leaves more than 1 m of clearance from any obstacle in front of the cubicle; (2) if there is an obstacle on the lateral plane (i.e., where the cubicle partition is) in front ahead of the cow, put the obstacle in front of the fore knees; (3) if there is an obstacle in front of the cow on the median plane (e.g., neck or front rail), the position the obstacle between 1.25 and 1.5 of the cow length from the curb and between 1.0 and 1.25 of its height; (4) use curb height between 0.11 and 0.15 of cow height with no sharp edges on the curb; (5) use round or at least has no sharp edges brisket board; (6) use a stone-free soil instead of concrete or use a mattress thicker than 1 cm, with microrelief, and a soft fixing area at the curb, (7) litter with straw (rather than nothing or sawdust) and keep it dry. This risk factor analysis should be followed by experiments in controlled environments to further validate these conclusions and used to update the International Commission of Agricultural and Biosystems Engineering recommendations.     

Competition at the feed bunk changes the feeding, standing, and social behavior of transition dairy cows

Transition dairy cows are vulnerable to the negative consequences of depressed feed intake around calving. Competition can decrease feeding activity in midlactation cows, but the effects of competition on the transition cow are not well understood. The objective was to test the effect of competition on the behavior and feed intake of transition cows. Standing behavior, feeding behavior, and dry matter intake were monitored from 1 wk before to 2 wk after calving for 36 Holstein dairy cows. Displacements at the feed bins were recorded the week before calving. Cows were assigned to either competitive (2:1 cows:feed bin) or noncompetitive (1:1 cow:feed bin) treatments. Treatment groups were balanced for parity and baseline feeding measures, resulting in 8 primiparous and 10 multiparous cows per treatment. Competition increased the number of displacements at the feed bins for both primiparous and multiparous cows. Primiparous cows had no change in feed intake or standing time when fed in a competitive environment, but did increase the time spent for each meal during the week before calving (28 ± 1.5 vs. 24 ± 1.5 min/meal). In the week before and after calving, competitively fed multiparous cows had a lower feeding time per visit than noncompetitively fed cows (4.2 ± 0.5 vs. 5.8 ± 0.5 kg/visit and 5.3 ± 0.7 vs. 7.0 ± 0.7 kg/visit, respectively). Multiparous cows ate at a faster rate 2 wk after calving (142 ± 11 vs. 105 ± 11 g/min). Multiparous cows in the competitive treatment increased the time they spent standing (without eating) during the week after calving compared with cows in the noncompetitive treatment (820 ± 44 vs. 649 ± 44 min/d). Feeding rate was correlated with a displacement index in multiparous cows, whereby cows with lower displacement indices ate more rapidly. Results indicate that restricting access to feed increases displacements regardless of parity, and alters the feeding and standing behavior of primiparous and multiparous cows differently.     

Effects of three types of free-stall surfaces on preferences and stall usage by dairy cows

One important criterion in choosing appropriate housing systems for dairy cattle is that the freestall provides a comfortable surface for the cow. This paper describes two experiments testing the effects of commonly used lying surfaces on stall preference and stall usage by Holstein cows. In both experiments, 12 cows were housed individually in separate pens. Each pen contained three free stalls with a different surface: deep-bedded sawdust, deep-bedded sand, and a geotextile mattress covered with 2 to 3 cm of sawdust. The animals were restricted to each surface in turn, in a random order for either 2 (Experiment 1) or 3 d (Experiment 2). Both before and after this restriction phase, the animals were allowed access to all three surfaces, and preference was determined, based on lying times. Of the 12 cows used in Experiment 1, 10 preferred sawdust before and nine after the restriction phase. During the restriction phase, average lying times and number of lying events during the restriction phase were significantly lower for the sand-bedded stalls (P < or = 0.05), and standing times were higher on mattresses (P < or = 0.05), compared with sawdust. Although these cows had some experience with all three surfaces during the experiment, they had been housed in sawdust-bedded stalls during their previous lactation. Cows used in Experiment 2 had spent their previous lactation in sand bedded stalls. In this experiment, about half the cows preferred sand and half sawdust, after the restriction phase. During the restriction phase of experiment, lying times and number of lying events were lower, and standing times were higher when the animals were restricted to the mattresses compared to either sand or sawdust (P < or = 0.05). These results indicate that (1) free stall surface can affect both stall preferences and stall usage, and (2) mattresses are less preferred.     

Calving body condition score affects indicators of health in grazing dairy cows

The objectives of this study were to determine the effect of calving body condition score (BCS) on cow health during the transition period in a pasture-based dairying system. Feed inputs were managed during the second half of the previous lactation so that BCS differed at drying off (BCS 5.0, 4.0, and 3.0 for high, medium, and low treatments, respectively: a 10-point scale); feed allowance was managed after cows were dried off, such that the BCS differences established during lactation remained at the subsequent calving (BCS 5.5, 4.5, and 3.5; n = 20, 18, and 19, for high, medium, and low treatments, respectively). After calving, cows were allocated pasture and pasture silage to ensure grazing residuals >1,600 kg of DM/ha. Milk production was measured weekly; blood was sampled regularly pre- and postpartum to measure indicators of health, and udder and uterine health were evaluated during the 6 wk after calving. Milk weight, fat, protein, and lactose yields, and fat content increased with calving BCS during the first 6 wk of lactation. The effect of calving BCS on the metabolic profile was nonlinear. Before calving, cows in the low group had lower mean plasma β-hydroxybutyrate and serum Mg concentrations and greater mean serum urea than cows in the medium and high BCS groups, which did not differ from each other. During the 6 wk after calving, cows in the low group had lower serum albumin and fructosamine concentrations than cows in the other 2 treatment groups, whereas cows in the low- and medium-BCS groups had proportionately more polymorphonucleated cells in their uterine secretions at 3 and 5 wk postpartum than high-BCS cows. In comparison, plasma β-hydroxybutyrate and nonesterified fatty acid concentrations increased linearly in early lactation with calving BCS, consistent with a greater negative energy balance in these cows. Many of the parameters measured did not vary with BCS. The results highlight that calving BCS and, therefore, BCS through early lactation are not effective indicators of functional welfare, with the analyses presented indicating that both low and high BCS at calving will increase the risk of disease: cows in the low group were more prone to reproductive compromise and fatter cows had an increased risk of metabolic diseases. These results are important in defining the welfare consequences of cow BCS.     

Effect of softer flooring in tie stalls on resting behavior and leg injuries of lactating cows

To test the advantages of softer flooring in tie stalls, we compared the behavior and injuries of dairy cows housed in tie stalls with either soft rubber mats (n = 12) or concrete flooring (n = 12), both lightly covered with straw. Data were collected for 112 d beginning at 14 DIM (±4 d). Cows’ general activity was observed continuously for 24 h every 28 d. Behavior was also scored by a scan sampling technique every 14 d such that each cow was observed for a period of 3 min every 12 min. We scored the occurrence of leg lesions and other injuries every 7 d throughout the study. Cows on rubber mats had shorter bouts of lying but the frequency of bouts was higher, leading them to tend to spend more time lying compared with cows housed on concrete. Cows on concrete spent more time standing idle, but there was no difference in the time spent eating. There was no effect of stall flooring on the number of minor abrasions to the legs and body. There was a significantly higher incidence of swelling of the carpus joints for cows housed on concrete. Cows housed on soft rubber flooring appeared to be less hesitant to change posture from lying to standing (and vice versa), and as a result changed posture more frequently and spent more time lying than cows on concrete flooring. The decreased incidence of swelling of the carpus joint for cows on soft rubber mats may have important long-term effects in preventing a variety of leg problems.     

Associations between herd-level factors and lying behavior of freestall-housed dairy cows

Our objective was to investigate the associations between herd-level factors and lying behavior of high-producing dairy cows housed in freestall barns. Lying behavior of approximately 40 focal cows in one high-producing pen was monitored on each of 40 farms in the northeastern United States (NE) and 39 farms in California (CA). All cows within the pen were gait scored using a 1-to-5 scale to calculate the prevalence of clinical lameness (score ≥3) and severe lameness (score ≥4). Facility and management measures, including stall design, bedding, and flooring type within the pen, were collected. Herd-level factors associated with daily lying time, standard deviation (SD) of daily lying time, frequency of lying bouts, and lying bout duration at the univariate level were submitted to multivariable general linear models. In the NE, daily lying time increased with the use of deep bedding (estimate = 0.80 ± 0.31 h/d) and as average days in milk (DIM) of the focal cows increased (estimate = 0.08 ± 0.04 h/d for a 10-d increase in DIM). The SD of daily lying time decreased as stall stocking density increased (estimate = −0.08 ± 0.03 h/d for a 10% increase), and increased with the presence of rubber flooring in the pen (estimate = 0.16 ± 0.08 h/d) and percentage of stalls with fecal contamination (estimate = 0.04 ± 0.01 h/d for a 10% increase). Frequency of lying bouts decreased (estimate = −1.90 ± 0.63 bouts/d) and average bout duration increased (estimate = 15.44 ± 3.02 min) with the use of deep bedding. In CA, where all farms used deep bedding, daily lying time increased as average DIM of the focal cows increased (estimate = 0.08 ± 0.03 h/d for a 10-d increase). The SD of daily lying time decreased when feed was delivered more than once per day (estimate = −0.24 ± 0.08 h/d). The percentage of lame cows was correlated with the percentage of stalls with fecal contamination (r = 0.45), which in turn was associated with fewer (estimate = −0.25 ± 0.06 bouts/d) and longer lying bouts (estimate = 1.85 ± 0.39 min/d). These findings suggest that lying time be interpreted in conjunction with variability in lying time and bout structure and in context with lameness prevalence, production parameters, and facility characteristics.     

Effect of following recommendations for tiestall configuration on neck and leg lesions,lameness, cleanliness,and lying time in dairy cows

Cow comfort in tiestalls is directly affected by stall dimensions, for which some recommendations exist. To evaluate how well Canadian dairy farms with tiestalls complied with recommendations for stall dimensions, as well as the effect of compliance on cow comfort and cleanliness, we assessed lactating Holstein cows (n = 3,485) on 100 tiestall dairy farms for neck and leg lesions, lameness, and cleanliness and measured time spent lying down. Data on stall dimensions (width and length of the stall, position and height of the tie rail, length of the chain, and height of the manger curb) were recorded for each cow. The majority of cows were housed in stalls smaller than recommended. The prevalence of lesions and lameness was high (neck, 33%; knee, 44%; hock; 58%, lameness, 25%) and the prevalence of dirtiness was low (udder, 4%; flank, 11%; legs, 4%). Chains shorter than recommended increased the risk of neck, knee, and hock lesions. A tie rail further back in the stall than recommended increased the risk of neck, knee, and hock lesions and reduced the frequency of lying bouts and the risk of a dirty udder. A tie rail set lower than recommended decreased the risk of neck lesions and lameness and increased lying time and lying bout frequency. Stalls narrower in width than recommended increased the risk of neck injuries and lameness and reduced the daily duration of lying time and the risk of a dirty flank and legs. Stalls shorter in length than recommended increased the risk of knee lesions and reduced lying bout frequency and the risk of a dirty udder. The majority of farms do not follow recommendations for stall dimensions (with the exception of tie rail height), and the lack of compliance is associated with increased risk of lesions and lameness and can affect lying time. Recommended stall dimensions tend to reduce cleanliness, but the prevalence of dirty cows remains very low.     

Feed stalls affect the social and feeding behavior of lactating dairy cows

The first objective of this study was to study the effects of increased bunk space on the frequency of aggressive behavior at the feed bunk and on feed access. The second objective was to determine whether the addition of partitions (feed stalls) between adjacent cows would provide additional protection while feeding, particularly for subordinate cows. Twenty-four lactating Holstein cows were subjected to each of 3 treatments in 3 successive 10-d treatment periods using a 3 × 3 Latin square design. The treatments tested were: 1) 0.64 m of feed bunk space/cow, 2) 0.92 m of feed bunk space/cow, and 3) feed stalls (0.87 m of feed bunk space/cow with feed stall partitions separating adjacent cows). Time-lapse video was used to quantify the feeding and standing behavior, as well as the aggressive behavior (displacements) displayed by the cows at the feed bunk. To meet our first and second objectives, we compared data from the 0.64 m/cow treatment with that from the 0.92 m/cow treatment, and data from the 0.92 m/cow treatment with that from the feed-stall treatment, respectively. Total daily feeding time increased when feed bunk space was increased from 0.64 to 0.92 m/cow. Further, the time spent standing in the feeding area while not feeding and the frequency of aggressive interactions at the feed bunk decreased when more bunk space was provided. The addition of feed stalls resulted in more pronounced effects compared with when cows had 0.92 m/cow of bunk space. The feed stalls also forced cows to change the strategy by which they displaced others from the feed bunk, forcing them to also initiate contact at the rear of the animal they were displacing rather than only from the front and side, as in the other 2 treatments. Further, when the cows were provided with additional feeding space, particularly when combined with feed stalls, those cows with lower social status at the feed bunk experienced the greatest decreases in the number of times they were displaced per day. The results indicated that providing increased feed bunk space, particularly when combined with feed stalls, will improve access to the feed and reduce competition at the feed bunk, particularly for subordinate cows.     

Measuring the feeding behavior of lactating dairy cows in early to peak lactation

The objectives of this study were to: 1) objectively define meal criteria (minimum interval between meals) of free-stall housed cows fed via a feed alley, 2) determine which measures of feeding behavior were most repeatable, and 3) describe changes in the feeding behavior from early to peak lactation. An electronic monitoring system was used to record individual cow presence (hits; 6-s resolution) at the feed alley for 21 lactating cows for three 8-d periods: period 1, 35 +/- 16 (mean +/- SD), period 2, 57 +/- 16, and period 3, 94 +/- 16 DIM. A mixture distribution model was used to calculate the meal criterion (27.74 min) by fitting the log10 frequency distribution of the intervals between hits. The within-cow repeatability was highest for feeding activity (hits d(-1)) and intensity (hits per meal min), moderate for total daily mealtime (min d(-1)) and meal duration (min meal(-1)), and lowest for meal frequency (meals d(-1)). From periods 1 to 2, all cows showed increases in total daily mealtime, meal frequency, and meal duration; however, cows with lower meal frequencies and feeding intensity in period 1 showed the greatest increases. Cows with high feeding activity and intensity during period 2 showed proportionally greater increases during period 3. These results illustrate that some measures of feeding behavior are highly repeatable within cows, but variable between cows and across stages of lactation. Thus, tests of treatment effects on feeding behavior should be within cow and control for days in milk.     

Technical note: Mining data from on-farm electronic equipment to identify the time dairy cows spend away from the pen

The electronic equipment used on farms can be creatively co-opted to collect data for which it was not originally designed. In the current study, we describe 2 novel algorithms that harvest data from electronic feeding equipment and data loggers used to record standing and lying behavior, to estimate the time that dairy cows spend away from their pen to be milked. Our 2 objectives were to (1) measure the ability of the first algorithm to estimate the time cows spend away from the pen as a group and (2) determine the capability of a second algorithm to estimate the time it takes for individual cows to return to their pen after being milked. To achieve these objectives, we conducted 2 separate experiments: first, to estimate group time away, the feeding behavior of 1 pen of 20 Holstein cows was monitored electronically for 1 mo; second, to measure individual latency to return to the pen, feeding and lying behavior of 12 healthy Holstein cows was monitored electronically from parturition to 21 d in milk. For both experiments, we monitored the time each individual cow exited the pen before each milking and when she returned to the pen after milking using video recordings. Estimates generated by our algorithms were then compared with the times captured from the video recordings. Our first algorithm provided reliable pen-based estimates for the minimum time cows spent away from the pen to be milked in the morning [coefficient of determination (R²) = 0.92] and afternoon (R² = 0.96). The second algorithm was able to estimate of the time it took for individual cows to return to the pen after being milked in the morning (R² = 0.98), but less so in the afternoon (R² = 0.67). This study illustrates how data from electronic systems used to assess feeding and lying behavior can be mined to estimate novel measures. New work is now required to improve the estimates of our algorithm for individuals, for example by adding data from other electronic monitoring systems on the farm.     

Competition for feed affects the feeding behavior of growing dairy heifers

The objective of this study was to determine how competition for feed influences the feeding behavior of young, growing dairy heifers. Thirty-six prepubertal Holstein heifers (231.5 ± 12.1 d old, weighing 234.7 ± 24.0 kg), consuming a total mixed ration ad libitum, were assigned to 1 of 2 treatments: noncompetitive (1 heifer/feed bin), or competitive (2 heifers/feed bin). After 7 d of treatment adaptation, dry matter intake and feeding behavior were monitored for 7 d for each animal. Fresh feed and orts were sampled on the last 3 d of the treatment period from each bin and were subjected to particle size analysis. The particle size separator consisted of 3 screens (18, 9, and 1.18 mm) and a bottom pan resulting in 4 fractions (long, medium, short, and fine). Sorting activity for each fraction was calculated as the actual intake expressed as a percentage of the predicted intake. There was no difference in sorting behavior or dry matter intake between the treatments. Overall, the heifers sorted against long particles (94%), and sorted for medium (102%) and short (103%) particles. The competitively fed heifers tended to have 10% shorter feeding times, particularly at peak feeding periods. The competitively fed heifers also consumed 9% fewer meals per day, although the duration of these meals were 10% longer, and tended to be 13% larger. Competition for feed also tended to increase the day-to-day variation in feeding time, meal duration, and meal size. It can be concluded that competition for feed for growing dairy heifers alters feeding patterns, reduces access to feed, particularly during periods of peak feeding activity, and tends to increase day-to-day variation in feeding behavior.     

Preference and usage of pasture versus free-stall housing by lactating dairy cattle

The aim of the current study was to assess if cows preferred pasture or indoor housing, and how diurnal and environmental factors affected this preference. Lactating dairy cows (n = 5 groups, each containing 5 cows) were sequentially housed either in a free-stall barn on pasture, or given the choice between the 2 environments. Each group was tested 3 times under each condition, for a total of 21 d, to assess the effects of varying climatic conditions (outdoor temperature ranged from 9.9 to 28.2°C and daily rainfall from 0 to 65 mm/d over the course of the experiment). When provided the choice, cows spent on average (± SD) 13.0 ± 0.6 h/d on pasture, mainly at night. The time cows spent on pasture during the day decreased with the temperature-humidity index (R² = 0.55); time on pasture at night decreased with rainfall (R² = 0.12). When provided a choice, cows spent more of their lying time on pasture (69.4 ± 0.02% of the total lying time/d) than indoors in the free-stalls. Cows also spent more time in total lying down when provided a choice than when confined to pasture [0.6 h/d more lying time; standard error of the difference (SED) = 0.21 h/d] and spent even more time lying down when confined indoors (1.1 h/d more time; SED = 0.21 h/d). Cows used the indoor housing especially for feeding; feeder use peaked when cows returned from morning and afternoon milkings. However, cows with free access to pasture spent 1.0 h/d (SED = 0.09 h/d) less time eating the TMR available indoors, resulting in a decline in intake of 2.9 kg of dry matter/d (SED = 0.36 kg of dry matter/d). How cows used the indoor housing differed when cows were provided a choice; for example, cows spent a greater percentage of their time indoors at the feed alley both during the day (47% of the total time spent indoors, versus 41% for cows confined indoors, SED = 0.02%) and at night (22 vs. 5%, SED = 0.04%). In conclusion, under the housing and environmental conditions tested, cows showed a strong preference for access to pasture at night and for access to indoor housing during the day when temperature and humidity increased.     

Effect of frequency of feed delivery on the behavior and productivity of lactating dairy cows

The objective of this study was to determine the effect of feed delivery frequency on the behavioral patterns and productivity of lactating dairy cows. Twelve freestall-housed, lactating Holstein dairy cows, including 6 primiparous (PP) and 6 multiparous (MP), milked 3×/d (at 1400, 2200, and 0600h), were exposed to each of 3 treatments (over 21-d periods) in a replicated Latin square design. Treatments included feed delivery frequency of (1) 1×/d (at 1400 h), (2) 2×/d (at 1400 and 2200 h), and (3) 3×/d (at 1400, 2200, and 0600 h). Milk production as well as feeding, lying, and rumination behaviors were electronically monitored for each animal for the last 7 d of each treatment period. Milk samples were collected for the last 3 d of each period for milk component analysis. Dry matter intake (DMI) varied with feed delivery frequency, with greatest DMI observed in cows fed 3×/d (27.8 kg/d) compared with those fed 2×/d (27.0 kg/d) or 1×/d (27.4 kg/d). Treatment had no effect on milk yield (41.3 kg/d) or efficiency of production (1.54 kg of milk/kg of DMI). Cows that did not receive delivery of feed following the 2200 h milking (treatment 1) and 0600 h milking (treatments 1 and 2) had lower DMI during the first hour after milking than those that received feed at all milkings (treatment 3). Total feeding time and meal frequency, size, and duration did not vary by treatment, but PP cows consumed smaller meals at a slower rate, resulting in lower DMI compared with MP cows. Primiparous cows consumed 50.1% and 26.1% less dry matter than MP cows during the first meal following the first and second milkings, respectively. Lying time did not vary by treatment, but PP cows spent more time lying (10.3 vs. 8.3 h/d) than MP cows. Under 3×/d milking schedules, greater feed delivery frequency resulted in greater DMI as a function of increased DMI following the return from milking and the delivery of feed.