Comparison of Commonly Used Indices to Evaluate Dairy Cattle Lying ...

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Jan 29, 2003 - ABSTRACT. Cows need to spend considerable time lying for maximum feed efficiency (decreased maintenance energy requirements and ...
This is not a peer-reviewed article. Pp. 125-130 in Fifth International Dairy Housing Proceedings of the 29-31 January 2003 Conference (Fort Worth, Texas USA) Publication Date 29 January 2003. ASAE Publication Number 701P0203, ed. Kevin Janni

COMPARISON OF COMMONLY USED INDICES TO EVALUATE DAIRY CATTLE LYING BEHAVIOR M. W. Overton, D. A. Moore, and W. M. Sischo1

ABSTRACT Cows need to spend considerable time lying for maximum feed efficiency (decreased maintenance energy requirements and effective rumination) and for optimum health (prevent lameness). Several indices are used by dairy consultants to evaluate cow comfort in free stall barns. The purpose of this paper is to compare three indices of free stall use, proportion lying, stall use index, and comfort index, and factors that affect their interpretation. Time-lapse video photography was used to examine effects of environmental temperature and management on dairy cattle lying behavior and to compare three commonly used methods for evaluating free stall usage during summer conditions in a high producing dairy. Four video cameras and six temperature probes were mounted in one free stall pen containing 144 stalls and 129 highproducing Holstein-Friesian cows. Over a six-day period in July 1999, a time-lapse video recorder continuously captured observations on tape. Videotapes were reviewed using 60-min scan sampling techniques. Free stall-use index was defined as the number of cows lying divided by the total number of cows lying or standing but not eating. Cow comfort index was calculated as number observed lying in stalls divided by the total number either lying or standing in a stall. Increasing time elapsed since milking and higher environmental temperatures negatively influenced the stall-use index as evaluated with 60-minute scan sampling techniques. Using the cow comfort index instead of stall-use index or proportion lying resulted in less variation between time periods and an average of 89% over the entire study period.

INTRODUCTION Total confinement free stall housing is an increasingly popular choice for new dairies in order to maximize stocking density and management efficiency, but basic cow comfort, health and behavioral needs must be adequately addressed. Lameness in dairy cattle is increasing and is most likely associated with housing conditions and intensive management directed primarily at achieving higher milk production (Greenough and Weaver, 1997). Total confinement on concrete in poorly designed or mismanaged housing facilities can interfere with resting behavior and normal social interactions (Bickert and Cermak, 1997; Greenough and Vermunt, 1991; Singh et al., 1993). Disturbed rest is a stressor that may lead to altered levels of cortisol in dairy cattle, and may increase the risk of involuntary culling, lower milk production, and reduce reproductive efficiency (Ladewig and Smidt, 1989; Muller et al., 1989). Assessment of housing systems for adequate cow comfort and rest can be difficult. Time-lapse photography has been used to measure lying, eating, or standing times through either continuous or scan sampling in small groups of cattle (Friend and Polan, 1974; Galindo and Broom, 1993; Menzi and Chase, 1994). Müller et al.(1989) suggested that observations should be sufficient in number and done at a set time, such as following the morning feeding, in order to provide reasonable comparisons between housing systems and evaluations for cow comfort. Although dairy consultants and veterinarians agree that cows should be spending at least 12 hours per day lying, most have no access to photographic techniques or time for videotape review. Many advisors, therefore, rely on walk-through observations to assess cow comfort and free stall usage for groups rather than in individual animals. Total proportion lying is occasionally used, but fails to account for beneficial time spent eating. Proportion eligible lying or “stall-use index” is 1

Veterinary Medicine Teaching and Research Center, University of California-Davis School of Veterinary Medicine, Tulare, California

another measure that adjusts for cows that are eating by excluding them from the calculation. It indirectly estimates the proportion of animals engaged in idle standing. Another very common index is the “cow comfort index”, a term that advisors use to estimate cows’ acceptance of stalls. The numerator consists of cows lying in free stalls and the denominator is the total number of cows touching a stall. A value greater than 85% is the desired goal. However, time elapsed since feed delivery or milking and ambient temperature at the time of observation is likely to impact the evaluations. Overton et al. (2002) examined the effects of feed delivery, time of milking, and environmental temperature on lying behavior in free stall housed dairy cattle and found a non-random cyclicity to lying behavior. Time since milking and free stall temperature were significant independent influences on lying behavior. Upon return from milking, most cows gathered at the feedline to eat and then sought out stalls in which to rest. As time elapsed since milking, resting behavior became more individualized. In addition, as environmental temperatures increased, lying decreased. Their conclusion was that for a one time walk-through of free stall barns during summer heat stress conditions, maximum proportion lying could be expected approximately 1 hour after the early morning milking. Unfortunately, management procedures such as feed delivery, milking, and feed push-up are not always consistent and consultants can’t always observe cattle at the optimal time. The objective of this paper is to compare the three major indices used to evaluate dairy cattle free stall barns by means of time-lapse video photography scan sampling techniques and to describe factors that may affect their interpretation.

MATERIALS AND METHODS Study Herd This observational study was conducted in a sand-bedded free stall facility housing 500 HolsteinFriesian cows that averaged approximately 12,000 kg of energy-corrected milk with 3X milking. The free stall barn was a four-row, head-to-head design with a center drive through feed alley and contained four pens under a 4/12 pitch roof. The study pen was located on the southeast side of the barn and contained 144 free stalls, 129 cows, and 140 headlocks. The free stalls were designed with open forward lunge, cantilever dividers, and a lying surface of 1.2 m wide by 1.7 m long. Cows were milked three times daily at 4:00 a.m., 12:00 noon, and 7:45 p.m. and total time spent away from the housing pen was limited to 2 to 3 h daily. Cows were cooled using large droplet/ low pressure sprinklers and fans. A total mixed ration was delivered once daily onto a flat, concrete feed apron and feed was pushed up 6 times daily. Data Recording Filming took place during 8 consecutive days in July, 1999 using four black and white closed circuit video cameras (EXXIS Security Systems, models ES450 and ER0024T, Lewisville, Texas∗). (Due to recorder malfunction, video data were not recorded on July 25 and due to darkness, no observations were recorded from approximately 10:30 p.m. to 2:30 a.m. daily.) Observations of cow behavior were made using hourly scan samples. Videotape review included all hourly intervals from 3:00 a.m. to 10:00 p.m. except for 8:00 p.m., when cows were away from the free stall barn for milking. As a result, 19 hourly observations were recorded for each day of the study. Cows were counted as lying, eating, standing-out, or standing-in a stall in each quarter of the pen according to the following definitions: Lying: resting in total lateral or sternal recumbency on a free stall surface Standing-out: standing or walking, but not eating or drinking Standing-in: standing with two or more feet touching a stall bed ∗

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Eating: actively consuming feed or water or standing within 0.6 m of the bunk and oriented toward the feed Proportion lying: number lying divided by total number in pen Proportion eligible lying (“stall-use index”): total number lying in free stalls divided by the total number of cows not eating during that time period “Comfort Index”: number observed lying in stalls divided by the total number either lying or standing in a stall for that time period In addition, temperature probes (Optic StowAway Temp, Onset Computer Corporation, Bourne, MA ) were suspended inside white open-ended PVC pipe (to protect the probes from cows and direct sunlight) and mounted on each end of the pen and at various locations along the feed bunk and free stall area at cow level. These data loggers automatically recorded ambient temperatures every 10 seconds.

RESULTS AND DISCUSSION Environmental Data The average temperatures from each of the recorded locations are shown in Figure 1. There were no differences in temperature between locations along the feedbunk, within the free stalls, or between feedbunk and free stalls, but there were large differences between the east and west ends of the pen. Early morning sun exposure on the east end of the open gable created heating effects that resulted in rapid increases in temperature (even though the probe was protected from direct sun exposure).

Figure 1: Average temperatures from throughout the study period.

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Lying Behavior Overall, the free stall design and management promoted good cow comfort as evident by an average comfort index of over 85% for all time periods measured. (Figure 2) Of interest was the cyclicity of lying behavior as shown by lying proportion. Overton et al., (2002) found a repeating pattern of cyclical resting behavior when they used proportion eligible lying (or stall use index) as the outcome. In the current study, cows were milked at 4:00 a.m., 12:00 p.m., and again at 8:00 p.m. and we observed a large drop in proportion lying during the first hour postmilking, followed by a sharp rise in percent resting over the next few hours. In addition, there were also fewer cows observed lying during mid-day and early evening hours as compared to similar times post-milking during a.m. observations. The increased resting during the early morning hours was also found by other investigators (Ruckebusch, 1972; Miller and WoodGush, 1991; O’Connell et al., 1989; Kondo et al., 1984). Cows should spend a greater proportion of time lying at night or during the very early morning hours unless otherwise preoccupied by feeding, milking or management disruptions provided there are adequate resting locations. Understocking of cows in the present study pen ensured an adequate number of resting locations.

Figure 2: Average lying indices (along with 1-standard deviation error bars) over all observations.

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In the study pen, a one-time walk-through appraisal of lying behavior could yield different conclusions depending on the time of evaluation and index used. For example, if an advisor had visited the dairy at 6:00 a.m. during the first day of the study, he would have concluded that the dairy was doing an excellent job managing dairy cattle resting needs as evidenced by a comfort index, stall-use index, and proportion lying index of over 85% each. However, if the same assessment were performed at a different time, a different conclusion is possible. For example, at 1:00 p.m., proportion of cows lying was only 22% while stall use index was better at 65%, but still below the goal of 75%. Both indices suggest problems with cow comfort and stall utilization. The major reason for the discrepancy between these two indices was the large proportion of cows that were eating at this time (1 hour post-milking) that adjusted the stall-use

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index. The comfort index was 83% indicating adequacy of stall comfort. At this 1:00 p.m. observation period, many of the cows that were not eating or occupying a stall were moving towards stalls or waterers and were not idly standing. Heat appears to impact lying behavior when evaluated by stall-use index or proportion lying. Previous research has demonstrated cows spending more time standing as environmental temperatures increase in an attempt to maximize evaporative cooling from body surfaces (Shultz, 1984; Igono et al., 1987). Possible reasons for a drop in lying behavior include cows standing under sprinklers and fans without eating in attempt to combat heat stress, cows walking toward waterers, and more cow-to-cow grooming as a result of stressful conditions (heat). Individuals evaluating free stall barns using one-time visual assessments for cow comfort should carefully consider the time of their evaluation in relation to time of milking and environmental temperatures. Use of proportion lying as an assessment index should be done very carefully as it is extremely variable depending upon time of observation. The use of two or more indices measured at two or more times should improve the accuracy of the visual evaluations. In addition, the observer should consider facility-specific problems when evaluating free stall usage. Inadequate stall numbers, obstacles within a pen such as temporary gates that subdivide a pen, or less than adequate crossover space may compromise freedom of movement and stall selection and result in an increase in idle standing (Metz-Stefanowska et al., 1993). On this dairy, stocking density and free stall design were not considered to be problematic. CONCLUSION Each of the three indices reported in the current study have merit in the evaluation of free stall usage, but care must be taken in their interpretation. Proportion lying contained the most variation within a day and stall comfort index had the least. Ambient temperatures compared within different areas of the barn were not different from each other except for the east pen end, which increased in response to direct sun exposure. On the dairy studied, stall comfort index was much less susceptible to management or temperature effects and resulted in less variation between observation periods. The best time to observe maximum stall usage was one hour after cows returned from the early morning milking (or two hours after cows left for milking). For one-time visual appraisals of free stall usage without knowledge of feed delivery time or other management issues, stall comfort index is the preferred index.

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Bickert, W. G. and J. Cermak. 1997. Pages 300-307 in Lameness of Cattle. 3rd ed. W.B. Saunders Co., Philadelphia, PA.

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Friend, T. H. and C. E. Polan. 1974. Social rank, feeding behavior, and free stall utilization by dairy cattle. J. Dairy Sc. 57: 1214-1220.

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Galindo, F. A. and D. M. Broom. 1993. The relationships between social behavior of dairy cows and the occurrence of lameness. Cattle Pract. BCVA 1: 360-365.

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Greenough, P. R. and J. J. Vermunt. 1991. Evaluation of subclinical laminitis in a dairy herd and observations on associated nutritional and management factors. Vet. Rec. 128:11-17.

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Greenough, P. R. and A. D. Weaver. 1997. Lameness of Cattle. 3rd ed. W. B. Saunders Company, Philadelphia, PA.

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Kondo, S., N. Kawakami, H. Kohama, and S. Nushino. 1984. Changes in activity, spatial pattern, and social behavior in calves after grouping. Appl. Anim. Ethol. 11: 217-228.

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Menzi, Jr. W. and L. E. Chase. 1994. Feeding behavior of cows housed in free stall barns. Pages 829-833 in Proceedings of the 3rd International Dairy Housing Conference, Am. Soc. Ag. Engineers. St. Joseph, Michigan

10. Metz-Stefanowska, J., A. H. Ipema, C. C. Ketelaar-de Lauwere, and E. Benders. 1993. Feeding and drinking strategy of dairy cows after the introduction of one-way traffic into the loose housing system, in the context of automatic milking. Pages 319-329 in Livestock Environment IV, Fourth International Symposium, Coventry, England. 11. Miller, K. and D. G. Wood-Gush. 1991. Some effects of housing on the social behaviour of dairy cows. Anim. Prod. 53: 271-278. 12. Müller, C., J. Ladewig, H. H. Thielscher, and D. Smidt. 1989. Behavior and heart rate of heifers housed in tether stanchions without straw. Physiol Behav. 46:751-754. 13. O'Connell, J., P. S. Giller, and W. Meaney. 1989. A comparison of dairy cattle behavioural patterns at pasture and during confinement. Irish J. Agr. Res. 28: 65-72. 14. Overton, M.W., Sischo, W. M., and Moore, D. A. 2002. Using time-lapse video photography to assess dairy cattle lying behavior in a freestall barn. J. Dairy Sci. 85:2407–2413. 15. Ruckebusch, Y. 1972. The relevance of drowsiness in the circadian cycle of farm animals. Anim. Behav. 20: 637-643. 16. Shultz, T. A. 1984. Weather and shade effects on cow corral activities. J. Dairy Sci. 67:868873. 17. Singh, S. S., W. R. Ward, K. Lautenbach, J. W. Hughes, and R. D. Murray. 1993. Behavior of first lactation and adult dairy cows while housed and at pasture and its relationship with sole lesions. Vet. Rec. 133: 469-474. 18. Vasilatos, R. and P. J. Wangsness. 1980. Feeding behavior of lactating dairy cows as measured by time-lapse photography. J. Dairy Sci. 63:412-416.

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