Cow comfort- Need for the higher production and maximum profit
Dr. Shailendra Kumar Rajak, Email Id- shailendra06rajak@gmail.com
Subject Matter Specialist (Veterinary Science), KVK, Parsauni, East Champaran
Dr. Rajendra Prasad Central Agricultural University, Pusa, Samastipur
INTRODUCTION:
Dairy management is a very complex task, involving crop production, animal production, soil science, staffing, accounting etc. Efficient herd management requires not only good management of the dairy cow but also a need for business management. This is based on the Basic Economic Principles. Both herd and business management demand Monitoring and Controlling for day to day management to provide the best cow comfort for maximum benefit.
Cattle comfort is one of the main factors which influence profitability of dairy farms due to its association with involuntary culling, cow longevity and productive life (Garcia and Endres, 2008). Productive life has been defined as the number of lactations a cow completes before she is culled. A productive cow that remains longer in a farm allows for fixed and variable costs to be diluted. Furthermore, fewer replacements are needed yearly and the producer can concentrate in voluntary culling due to low production, allowing for an improvement in the genetic potential of the herd. Cow comfort is also important from an animal welfare perspective. Different methods to quantify dairy cattle comfort have been developed through the years. These have turned into useful indexes that point to general management flaws or inadequate facility design which increases the probability of a cow prematurely leaving the herd. Thus the objective of this paper is to review the indexes which maximize profits by optimizing cow comfort.
Growing interest in assessment of cow comfort has led to the development of several indices that can be used to measure the acceptability of a free-stall dairy barn environment to dairy cows. These indices include the following: 1) cow comfort index (CCI), the number of cows lying in a stall divided by the total number of cows in contact with a stall (Nelson, 1996); 2) stall standing index (SSI), the number of cows standing in a stall divided by the total number of cows in contact with a stall (Cook et al., 2005); and 3) stall use index (SUI), the numberof cows lying in a stall divided by the total number of cows in the pen not eating (Overton et al., 2003).
Evaluating Cow Comfort
The comfort of your herd means as much to your dairy’s success as your management and simple changes in your daily practices can greatly increase each cow’s productivity and reproductive performance. The following are four well-documented steps you can take to step up production.
• Decrease the time cows spend in the holding pen.
• Increase time spent eating and resting in clean, dry and comfortable free stalls.
• Use a heat-abatement system to mitigate high-temperature challenges. This will increase dry-matter intake, promote estrus activity and improve pregnancy rates.
• Minimize health challenges in early lactation such as retained placenta, ketosis, milk fevers and mastitis through good transition-cow management programs.
Access to Feed and Water
Feed and water are the basics for milk production. Naturally, special care needs to be paid to the design and management of these areas. Feeding areas should allow convenient delivery of rations and adequate space for the cows to consume their feed. Feed areas should be easy to clean and maintain. Your herd should always have access to plentiful water. So it’s important for waterers to provide plenty of clean, good-quality water and refresh fast enough to keep up with cow consumption.
Things to watch out for:
• Adequate supply of clean water
• Sufficient space so cows are not overcrowded when eating or drinking
• Feed that is pushed up. Feed bunks should not be empty for more than one to two hours per day.
It’s important to remember that close-up, fresh and early-lactation cows are particularly sensitive to changes in feeding, management and environment. These changes can affect dry-matter intake and an intake depression in these groups will quickly have a noticeable impact on herd performance and health. Under ideal cow comfort situations, there are six fundamental activities that make up a cow’s daily (24-hour) routine. These activities include: eating, milking, restraint for management activities, socializing, drinking, and lying down making milk. Milking and lock-up time activities are fixed amounts of time dependent upon facility design and management efficiency. The other activities (eating, drinking, socializing, and lying) are variable time activities that are dependent upon factors such as stall design, grouping, ration palatability, and bedding management. Reviewing the amount of time devoted to these activities each day, is a good indicator of whether you are optimizing cow comfort and avoiding non-productive activity like excessive time on concrete (Cermack, 1998).
Eating- Studies have shown that a cow’s Dry Matter Intake (DMI) is directly correlated to her level of production. Therefore, maximizing feed intake for your cows is a main component in increased production and profitability (Albright et al., 1989; Cermack, 1998). A good way to accomplish this is promoting good feed bunk management practices, such as frequent feed push-ups (10-15 times per day), daily cleaning of feed bunk and managing for 2-5% weigh backs. Ideally, cows will eat 6-15 meals per day of 4-9 lbs of DMI per meal, with each of these sessions lasting 20-30 minutes. So, that would add up to about 4.5 to 5 hours, or approximately 19%-21% of a cow’s day. The largest meals are eaten immediately after milking which necessitates that managers provide plenty of fresh ration when cows return from milking.
Milking- When we discuss milking turn time, most people think it is the pen size divided by the number of cows per hour the parlor will milk. However, when monitoring milking turn time, it is important to take into account the total milking time per pen plus additional time away from the feed bunk and free stalls. Total milking turn time starts when a pen is pushed to the parlor and ends when the last cow gets back to the pen, times the number of milking per 24 hours. Total Milking turn time should be less than 3 hours (13%) per day, regardless of how many times per day the cows are milked. An increase in this time takes away from a cow’s other activities, like eating and socializing, which can mean decreased milk production and heat expression.
Lock-up- As stated above, lock-up time is essential for different reasons on a dairy (heat detection, vaccinations, A.I., examinations, etc.). Although it is an important part of management, this should be a very minimal part of a cow’s day. The total time spent per day locked up or retained for management purposes should not exceed 1.5 hours (6%) per day. During long lock-up times, high producing cows may not be able to consume enough feed, even if adequate feed is available for the average producing cows. Long lock-ups may disrupt high producing cows’ usual eating habits, since they prefer to eat smaller amounts of feed more times a day. During summer heat stress, lock-up periods should occur before the heat of the day becomes significant and have shades overhead (Albright, et al., 1989; Arave et al., 1996).
Lying- In order to maximize milk production, a cow should spend over 12 hours, or greater than 50% of her day lying in a stall, lot or pasture. Several studies revealed that the amount of blood flow to the udder increases dramatically, when a cow is lying down and relaxed. A good evaluation of lying time is the Free stall Use Index (FUI). FUI is determined by counting all animals within a pen that are not eating or drinking and then calculating the percent of these animals that are lying down normally. The FUI should be measured 2-3 hours after milking time.
Optimal cow comfort will result in greater than 90% Freestall Use Index. Additionally, at least 50% or more of lying cows, should be chewing their cud. According to these researchers, as more and more modern dairies are going to a total confinement design, ability to lie cows down will have a big impact on cow longevity, foot health, and overall profitability.
Socializing- In general, socializing refers to the amount of time that a cow spends walking around or interacting with other animals around her. This includes grooming, exercising, licking, but most importantly, expression of heat. This aspect of a cow’s day may be largely influenced by cow health, environment, grouping and time allowed by other activities. On average, a cow spends about 1.5 hours (6%) of her day socializing.
Drinking- Water consumption is a crucial component to high milk production. A typical cow should spend 1 hour or 3 percent of her day consuming water. A high producing cow will drink 30-40 gallons of water per day, which equals three to four pounds of water per 1 pound of milk she produces. In order to maintain this level of consumption, water tanks should be located in 2-4 sites per penand cleaned once per day. There should be about 3 inches linear space allowed per cow or one space for 10 animals when using “hole” type water devices.
Cows have a strong behavioral need to rest
Recently, Jensen et al. (2004) demonstrated that cows have a very strong motivation to rest and that this motivation to rest increases the longer the cow is deprived of rest. In fact, lying behavior has a high priority for cattle after relatively short periods of lying deprivation. Cows have a definite requirement for resting (lying down) that they attempt to achieve, even if it means giving up some feeding time. A key concept is that feeding and resting behavior are linked in dairy cattle.
Resting time and Milk production
Milk production of dairy cows and resting time is positively associated. Study revealed that resting and feeding behavior are even linked during the transition period. First-calf heifers and mature cows that had greater lying and ruminating activity on days -2 and -6 pre-partum also had greater feed intake and milk yield during days 1 to 14 postpartum. This relationship raises an important question: how do we motivate cows to rest and ruminate during the close-up period?
Cows require 12 to 14 hours/day of rest (lying down). Benefits of resting include potentially greater milk synthesis due to greater blood flow through the udder, greater blood flow to the gravid uterus during late lactation, increased rumination effectiveness, less stress on the hoof and less lameness, less fatigue stress and greater feed intake. Grant (2004) proposed that each additional one hour of resting time translates into 2 to 3.5 more pounds of milk per cow daily as shown in figure 3.
Indices of cow comfort are used widely by consultants in the dairy industry, with a general understanding that they are representative of lying behavior. The study examined the influence of stall base type (sand or a geotextile mattress filled with rubber crumbs) and time of measurement on 4 indices of comfort collected at hourly intervals in 12 herds, aligned by morning and afternoon milking. Stall base type significantly influenced all indices of comfort. For example, the least squares mean (SE) cow comfort index (proportion of cows touching a stall that are lying down) was 0.76 (0.015) in herds with mattresses compared with 0.86 (0.015) in herds with sand stalls. Significant hourly variation was also identified suggesting that timing of measurement is important. None of the indices of cow comfort derived from the high-yielding group pen was associated with the mean 24-h lying time of 10 sentinel cows whose time budgets were known in each herd. However, the cow comfort index was associated with the herd mean 24-h stall standing time, with the strongest relationship occurring 2 h before the morning and afternoon milking, when stall base type did not significantly influence the association. When measured at these times, we recommend use of the stall standing index (proportion of cows touching a stall that are standing), with values greater than 0.20 being associated with abnormally long herd mean stall standing times greater than2 h/d (Cook et al., 2005).
Previous empirical research has not found a relationship between any of these indices and mean daily lying time but established a relationship between times spent standing in a stall and the SSI (Cook et al., 2005). This relationship was strongest when SSI was determined 2 h before removal from the pen for the morning or afternoon milking, which differed from the recommendation of Overton et al. (2002) to measure SUI approximately 1 h after returning to the pen from milking.
More recently, a relationship was established between lameness and CCI (Espejo and Endres, 2007). The prevalence of lameness for herds in the top quartile for CCI was approximately 50% less than for herds in the bottom quartile. The monitoring of cow comfort, or specifically stall standing and lying activity, may provide useful information on the state of the herd. Nevertheless, no information exists on how these indices should be utilized under different stocking densities that encompass the range observed on commercial dairies. Previous studies have used stocking densities ranging from 89% (Overton et al., 2002) to 108% (Cook et al., 2005), which are not reflective of the range found on dairy farms. Although Espejo and Endres (2007) evaluated CCI on farms with a wide range of stocking densities, the mean stocking density (109%) was similar to Cook et al. (2005). The 2-h reduction in daily lying time and decreased latency to lie down observed when stocking density was increased from 100 to 150% (Fregonesi et al., 2007) demonstrated that increased stocking density altered stall usage. Because of these results, it may be appropriate to monitor the ability of the cow to access and utilize a stall for resting in addition to measuring the proportion of cows lying that are actually in stalls. Different indices of comfort may be required for monitoring each of these separate components.
It was hypothesized that the SUI would decrease with greater stocking density, because it measures the ability of the cow to access stalls and incorporates the proportion of cow standingdly in alleys and not actively eating. The CCI and SSI would remain unchanged with higher stocking density, because they are more strictly a measure of stall comfort and the preference for standing or lying within a specific stall. The objective was to evaluate the effects of increasing stocking density (stall and headlock basis) on indices of cow comfort during a 24-h period between 0000 and 0400 h, and 1 h after the second (1200h) daily milking. The first aim was to quantify changes in CCI, SSI and SUI as stocking density increased incrementally from100 to 142%. The secondary aim was to establish whether a more accurate estimate of cow comfort on a pen level resulted from measuring CCI, SSI, or SUI over 24 h, between 0000 and 0400h, or 1 h after the second milking.
Holstein cows (n = 136) were selected for similarity in DIM and milk production at the William H. Miner Agricultural Research Institute (Chazy, NY) and had a mean locomotion score of 1.75on a 1- to 5-point scale (Flower and Weary, 2006). Cows were housed in a 4-row free-stall barn with stalls measuring 1.3-m wide, 2.6-m longand 1.3-m high at the neck rail. Bed surface consisted of a 1.7-m long foam-filled mattress (Foamat, Foxworthy Supply, Kent City, MI) covered by 10 kg of kiln-dried saw dust and each stall was cleaned when cows were removed for milking. Milking occurred 3 times daily at approximately 0400, 1200,and 2100 h. Alley surfaces within the pens consisted of rubber mats (Animat Inc., Saint-Élie d’Ordfort, Québec, Canada) over concrete, which were cleaned every 2 h by an automated scraper system (J. Houle et Fils Inc., Drummond-ville, Québec, Canada). Cows were fed a TMR formulated for 40 kg of milk production per day once daily and pushed up 6 times daily. Water was available for ad libitum consumption in troughs at the end of each pen and in the walkway between the pen and milking parlor.
Cows (n = 34) were housed in 1 of 4 pens containing 34 stalls and 47 headlocks. At 100% stocking density, 1 stall and 1 headlock were provided for each cow. Eliminating access to 0, 4, 8 and10 of the 34 stalls and 13, 17, 21, and 23 of the 47 headlocks simulated the 100, 113, 131, and 142% stocking densities. Each treatment was implemented in each pen for 7 d. Behavioral data were collected for 2 d with the initial 5 d utilized as an adjustment period. The percentage of cows lying, standing in a stall, standing in an alley, or eating was recorded from video data. The data from each of the replicated 24-h periods were analyzed with10-min scan samples for a total of 288 observations (6/h for48 h) per variable. Over each time period, the video data were collected using a total of 12 cameras (ULTRA Pro Series B/W,CCD DSP camera, Central Alarm Systems Inc., Littleton, CO) equipped with a 0.83-cm, 5- to 50-mm DC F1.7 CS-mount lens and a digital recorder (DiGi Cam 30 16-port Remote Surveillance and Digital Recording Package, version 7, Central Alarm Systems Inc.): 6cameras were mounted to the periphery of each pen at 457-cmheight to record activity within the free-stalls, and 6 cameras were mounted 467 cm above the feed bunk to record the number of cows feeding.
Comfort indices were calculated as: CCI = (number of cows lying in stalls/number of cows lying or standing within a stall) x100; SSI = (number of cows standing in stalls/number of cows lying or standing within a stall) x 100; and SUI = (number of cows lying in stalls/total number cows – number of cows eating) x 100.
Data were analyzed during the following periods: 24 h, 1 h after second milking and between 0000 and 0400. The measurement of a 24-h mean for cow comfort indices was based on the methodology of Cook et al. (2005). Assessing stall use and cow comfort during the period 1 h after milking was recommended by Overton et al. (2002).The period of peak lying behavior (0000 to 0400 h) for the farm corresponded to the period between the return from the third milking of the day and the daily delivery of fresh TMR (C. T. Hill, unpublished data). This period included the 2 h before the morning milking recommended by Cook et al. (2005) for observing stall use.
Treatment effects for indices of cow comfort and time spent standing idly in an alley were determined using a mixed model appropriate for a 4 x 4 Latin square design. Factors included in the model were pen, period, and stocking density. Pen was used as a random variable within the model. Analyses were computed using the mixed procedure of SAS (SAS Institute Inc., Cary, NC). When stocking density had an effect as a fixed variable (P< 0.05), differences between each stocking density of the study were separated using Tukey’s procedure at P< 0.05.
Optimizing Cow Activity
Evaluating your herd’s cow comfort and identifying problems is only the first step to increased profits. Finding solutions and eliminating bottlenecks is the next phase in successful cow comfort. Here are a couple different ways to keep cows off their feet and making milk.
Decreasing Milking Turn Time –
This may involve improved parlor routines that result in decreased unit on time, shutting down sprinkler pens or reducing pen sizes.
Lock-up times– Studies have shown that unless exceeding 4 hours per day, this is not a huge bottleneck on most dairies. According to research, the exception would be if animals become heat stressed while being locked (Shipka and Arave, 1995).
Improve Free stall Use Index – If FUI is less than 90% on your dairy, it likely represents your largest opportunity to correct excessive TOC. Why aren’t your cows using your free stalls? The two most common reasons are lack of lunge space or bedding surfaces that are compacted or uncomfortable to lie on. If using brisket boards, they need to be positioned 66-68 inches from the rear curb of the stall, placed at a 45-60 degree angle and not be higher than4 inches above the bedding surface. Excessive cows standing half in stalls maybe due to low neck rails or inadequate lunge space. Neck rails should be positioned, 46-48 inches above the bedding height, and should be placed 60-66 inches from the rear of the curb.
Install Rubber Belting or Mats – Many of today’s dairymen are exploring the use of rubber belting and mats in their facilities. According to Dr. Neil Michael, Director of Technical Services at ABS, rubber belting seems to work well in return and transfer lanes, while the commercial, softer rubber mats may work better in the feeding lanes. “I believe that rubber mats are keys for high producing cows in today’s commercial dairy operations to reduce time on concrete,” says, Michael. “I know this an expensive recommendation, but so are cows that can’t get to the feed bunk or have delayed conception due to lameness.” He also mentions that people need to be careful when purchasing conveyor belting, because some types are harder than others, depending on age, and it’s use prior to being used in the dairy.
Factors responsible for influencing Cow Comfort
Heat stress
Heat stress is a serious problem and can have a dramatic impact on milk production and herd reproduction in a farm. Fortunately there are a few proven ways to minimize the effect of heat stress.
• Water should be plentiful & immediately available
• Housing areas & holding pens should provide plenty of shade & should be well ventilated
• Holding pen times & walking distance should be reduced
• Well-designed cooling systems & fans should be installed
In barns with inadequate cow cooling, respiratory rates increase about 1.5 beats per minute (bpm) per degree 0F as temperature moves above thermoneutal zone, which is approximately 680F. Cows will exhibit increased standing as their rectal Temperature exceeds 1020F. Target goals to control heat stress are: Maximum respiratory rates of 70 bpm and rectal temp, below 1020F .
Stocking Rate
Fernandez et al. (2009) conducted a research on effect of Stocking Density on Indices of Cow Comfort with the objective to evaluate the effects of increasing stocking density on indices of cow comfort measured over a 24-h period, during peak lying time (0000 to 0400 h), and 1 h after the afternoon milking. Holstein cows (n = 136) were assigned to 1 of 4 pens and stocking densities of 100, 113, 131 and 142% were applied in a 4 x 4 Latin square. Video data were recorded continuously for 2 d after and 5 d of acclimation to stocking density and analyzed with 10-min scan samples for the percentage of cows lying in a stall, standing in a stall, standing in the alley and eating at the manger. They reported that percentage of cows standing in the alley increased as stocking density increased above113% (10.9, 12.0, 14.4, and 16.5% for 100, 113, 131 and 142%stocking density, respectively). Cow comfort index (CCI; cows lying down/cows contacting stalls) and stall standing index (SSI; cows standing in stall/cows contacting stalls) differed little as stocking density increased, but stall use index (SUI; cows lying in stall/cows in pen not eating) decreased beyond 113% stocking density (70.1, 70.2, 68.6, and 66.3 for 100, 113,131, and 142% stocking density, respectively). During peak lying time, SUI decreased with increasing (80.3, 79.5, 74.8, and 69.6for 100, 113, 131, and 142% stocking density, respectively) stocking density above 113%, whereas CCI and SSI showed little response. None of the indices varied by stocking density when they were assessed at 1 h after milking. These results suggest that more than 1 index of cow comfort may be needed at higher stocking densities to assess both stall usage and cows standing in an alley. At higher stocking densities, SUI was reduced, because it reflected not only stall usage but the number of cows standing idly in an alley and not actively feeding and unable to access a stall. The CCI and SSI appear to assess actual stall usage (% cows lying or standing) across the range of stocking densities evaluated in this study.
Comfortable, Profitable Cows
Ensuring cow comfort on your dairy is keys to profitability, whether it’s through higher milk production or improved pregnancy production. Using fundamental activity times to assess cow comfort can help you detect problems and then improve milking turn times, free stall use, or consider rubber matting key areas of your dairy as needed. All in all, optimizing essential cow activities puts money in your pockets.
Temperament
“No one likes wild cattle, so why raise them?” This quote, from The Lasater Philosophy of Cattle Raising (Lasater, 1972), seems obvious due to animal and handler safety concerns. Some beef producers do, in fact, consider temperament to be an important trait when selecting cattle for purchase (Elder et al., 1980). Often, however, the economic implications of livestock temperament have been unrecognized. Reports of very excitable cattle that become highly agitated and excited when restrained or handled are increasing (Grandin, 1994). This trend could possibly be counterproductive for the beef industry. One study reported that cows with calm temperaments had a 25 to 30% increases in milk production (Drugociu et al., 1977). Observations tend to show that more excitable cattle with higher temperament scores have lower live weights and (v) weight gains (Tulloh, 1961; Fordyce and Goddard, 1984), though few data have been presented. The present study was conducted to identify the relationship between temperament and productivity as measured by daily weight gain.
The following research was conducted using 466 cattle of different breeds and sex the following results were reported using five-point system for measuring temperament:
• 1: calm, no movement
• 2: restless shifting
• 3: squirming, occasional shaking of device (squeeze chute or scale)
• 4: continuous vigorous movement and shaking of device
• 5: rearing, twisting, or violently struggling.
Analysis of Breed Differences in Temperament data on the Bos indicus and Bos taurus cattle showed that temperament score differed between breed groups. No significant temperament score differences existed within B. indicus-cross cattle with respect to differing percentages of Brahman influence (1/4, 3/8, or 1/2 Brahman). Mean temperament scores of B. indicus-cross cattle were higher (P < .001) than those for B. taurus steers. This agrees with research that has shown that B. indicus cattle are more temperamental or excitable than B. taurus cattle (Elder et al., 1980; Hearnshaw and Morris, 1984; Fordyce et al., 1988). Because of these differences, weight gain data for B. indicus-cross and B. taurus breed groups were analyzed separately.
Even though an economic analysis has not been completed at this time, the benefits of selecting for calmer or more docile animals may be more than enhanced animals and handler safety and decreased facility wear. Another advantage of selecting cattle with calmer temperaments would be increased welfare because injuries to the animal would be reduced. This shows that selection for calm temperaments may become a key factor in maximizing production efficiency of cattle weight gains in feedlots. Cattle temperament is heritable and temperament differences persist when animals are rated over a period of time. These two factors, considered together, imply that careful selection for a calm temperament may not only improve animal and handler safety but also increase economic returns via improved average daily gains.
Talking about cow comfort involves listening to and understanding numerous opinions on this issue. But what is real cow comfort? How can it be judged? And may be even more importantly, how can it contribute to profitable dairy farming? Observation and experience show that cows housed in a comfortable environment produce more milk and generally live healthier, longer lives. Cows can’t explain what makes them comfortable. But we can observe and measure cow activity, behaviour and environment – then correlate our observations with what appear to be comfortable cows.
SUMMARY AND CONCLUSION-
It could be precisely conclude that cows should have plenty of quality feed and water, fresh air, a soft and clean resting surface plus sound footing.
Now that’s cow comfort! Cows should behave naturally and stand or lie down easily. Optimizing cow comfort is a key to profitability on any dairy, since optimal cow comfort results in higher milk production, improved herd health and increased reproductive success. Ensuring maximal cow comfort really comes down to knowing what activities your cows are experiencing during a 24-hour period. Thus, cow comfort is not a product or a tool – it is what is happening in and around the barn 24 hours a day, seven days per week. Seasonal variations influence it. Above all, cow comfort should be judged and managed with knowledge.
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