Sensor validation to record rumination and analysis of behavioral parameters of dairy Gyr heifers in feedlot systems.

The use of sensors for livestock monitoring has grown in the last decade, motivated not only by the search for improvements in animal production and health, but also by the better use of physical, financial, and human resources in the management of livestock. Since precision livestock farming depends on technological innovation, including the use of sensors, it is essential to validate their applicability in confined animals. Therefore, the objective was to evaluate the functioning of the SCR Heatime® HR System sensor in heifers and analyze the behavioral differences of these animals in two feedlot systems (tie-stall and loose-housing). Eleven Gyr heifers of 10 months of age and an average body weight of 179 ± 26 kg were used. Animals were equipped with the SCR Heatime® HR System 7 days before the evaluations for adaptation, with the behavioral and system studies carried out during two periods each of 5 days, for 8 h a day. Five heifers were housed in tie-stall bedding and six were housed in loose-housing. After the evaluations for a period, animals have been switched systems in the following period. While the animals had the sensors attached to their bodies, behavioral evaluations were also performed visually, every 3 min by two evaluators per system. Behavior activities were characterized as standing, lying, idle standing, idle lying, ruminating standing, ruminating lying, feed, and water intake. The regression for the rumination activity recorded between the sensor and the visual assessment was significant only for loose-housing (P = 0.0002), but the Pearson correlation between both was negative and low (r = - 0.25; P = 0.0002). The sensor overestimated rumination by 27.3% in loose-housing (28 vs. 22 min/2 h) and 38.5% in tie-stall (36 vs. 26 min/2 h). Thus, when considering the different feedlot systems, validation was not possible due to the overestimation of time spent on rumination activity determined by the sensor. In the behavioral comparison between the systems by visual assessment, there was a significant difference (P < 0.05) for the behaviors of motor activity, idle lying, total idle time, and feed intake between the animals in the two housing systems. As for idle standing, ruminating standing, total rumination time, and water intake, there was no difference (P > 0.05). However, the time spent ruminating lying was greater from 10:00 to 12:00 h (43 ± 3 min/2 h) in the tie-stall, whereas in the loose-housing the animals distribute more uniformly their rumination from 08:00 to 16:00 h (26 min/2 h on average). Therefore, the use of the SCR Heatime® HR System sensor is not recommended for Gyr heifers housed in tie-stall and loose-housing systems. Regarding the daytime range of rumination and the accuracy improvements of similar sensors, it is recommended to develop them in both feedlot systems using the periods of less rumination in early morning in tie-stall and late afternoon in loose-housing.

Relationships between type of hoof lesion and behavioral signs of lameness in Holstein cows housed in Canadian tiestall facilities.

Although foot pain can affect gait, the presence of a hoof lesion may or may not cause the cow to show visible changes in their gait. This can be dependent on the type and severity of the lesion; for example, the presence of a sole ulcer (SU) has been associated with increased gait scores, whereas digital dermatitis (DD) and sole hemorrhage (SH) have not. In tiestall facilities, gait scoring can be difficult to perform. An alternative method, known as stall lameness scoring (SLS), allows observers to assess cattle for lameness while they remain in their stall. Lameness is determined based on behavioral changes in weight bearing and foot positioning, which include: shifting weight, resting a foot, standing on the edge of the stall, and uneven weight bearing when stepping side to side. The aim of this study was to examine relationships between hoof lesions and these behavioral indicators. A total of 557 observations of SLS and corresponding hoof trimming records, collected during routine trimming events on 7 tiestall herds, were obtained. Trimming was performed by 2 trained hoof trimmers with good agreement on lesion identification, based on quizzes taken at the beginning and mid-way through the study. To ensure trimming had no effect on the behavioral indicators observed, SLS was always performed by a trained observer before trimming. Behavioral indicators focused on the hind limbs only; therefore, the analysis was confined to hind limb lesions using logistic regression to detect the presence of hoof lesion based on observations made during SLS. Seventy-five percent of observed cows had no SLS behavioral indicators, whereas, 11, 12, and 1% had 1, 2, and 3 behavioral indicators, respectively. At least one hind limb lesion was noted during trimming in 19% of cows, with the most common lesions being DD (7%), SU (6%), and SH (4%). A cow that was observed resting one foot and bearing weight unevenly when moving side to side had higher odds of having a hind limb hoof lesion than a cow not displaying these behaviors. When looking at specific hoof lesions, a cow observed resting one limb and bearing weight unevenly had higher odds of having a SU compared with those not displaying these behaviors. A cow observed shifting their weight from one foot to another had higher odds of having SH, and a cow observed bearing weight unevenly had higher odds of DD. Behavioral indicators in weight bearing and foot positioning can help identify cows in tiestalls with hind limb hoof lesions. Producers could routinely observe their cattle for these indicators to assist in the identification of cows that may require treatment. This could help reduce the duration of clinical lameness through earlier intervention.

Making tiestalls more comfortable: II. Increasing chain length to improve the ease of movement of dairy cows.

Although most farms in Canada still use tiestall housing for dairy cows, little information is available pertaining to cow comfort and behavior in such systems. Tiestalls are often criticized as they offer a reduced dynamic space to cows, thereby restricting their ability to move. The object of this study was to see if increasing the length of the tie chain provides cows with improved movement opportunities and to measure its effect on cows' rising and lying movements and behaviors. Two treatments were tested: the current recommendation of 1.00 m (recommended) and a longer chain of 1.40 m (long). Twenty-four cows (12/treatment) were blocked by parity number and lactation stage, then randomly allocated to a treatment and a stall within one of 2 rows in the research barn for 10 wk. Leg-mounted accelerometers were used to record lying behaviors and moments of transition between lying and standing positions for all cows. Cows were video-recorded for 24 h/wk using cameras positioned above the stall. The videos were used to evaluate the cows' rising and lying-down movements on wk 1, 2, 3, 6, 8, and 10. Six rising and 6 lying-down motions per cow per week were assessed by a trained observer to detect the presence of abnormal behaviors. Differences between and within treatments over time were analyzed in SAS (SAS Institute Inc., Cary, NC) using a mixed model with treatment, week, and block as fixed effects and with row and cow as random effects. Data from wk 1-3 were grouped together as the short-term effects, and those from wk 8-10 as the long-term effects. Week 6 was used as the mid-term assessment for analysis. Multiple comparisons between terms were accounted for using a Scheffé adjustment. Results indicate that duration of intention movements (exploratory head movements made by cows before lying down) is shorter in cows with longer chains (13.6 ± 1.03 s vs. 16.8 ± 1.01 s). It was also significantly shorter in the long term compared with the short term for both treatments (13.3 ± 0.92 s vs. 16.9 ± 0.81 s). These results suggest that increasing the chain length improves the cows' ease of movement and transitions, although all cows became more at ease in their surroundings with time. It may provide evidence of a potential way to improve the dynamic space provided to cows in tiestall systems, using a simple, affordable modification.

Symposium review: Considerations for the future of dairy cattle housing: An animal welfare perspective.

Many contemporary dairy cattle housing practices are at odds with societal perceptions of positive animal welfare. The public (i.e., those external to the dairy industry) typically emphasizes the importance of naturalness for dairy cattle, such as through provision of pasture, freedom of movement, and the ability to interact socially with conspecifics. Yet, in the United States, the majority of lactating dairy cattle are reportedly housed without any access to pasture, and almost 39% of dairy farms use tiestalls, which restrict movement and social interactions. In addition to being in conflict with public expectations, a lack of pasture access and restrictive housing systems are also in conflict with the animals' own motivations, which can adversely affect their welfare. For example, dairy cattle are highly motivated to access pasture and show a reduction in oral stereotypies when allowed on pasture after periods of tethering. Calves housed without social contact have cognitive deficits and exhibit increased fear responses to novelty. We argue that the long-term sustainability of the dairy industry will depend on the extent to which housing systems reflect public concerns and the animals' priorities. The adoption of technologies, such as automated feeders and remote monitoring systems, may represent a means to practically promote the animals' natural behavior while simultaneously improving individualized care. Although older generations of the public may consider technological solutions to be a further deviation from naturalness and a departure from dairy farming's agrarian roots, the definition of "naturalness" for younger generations may well have expanded to include technology. As the buying power shifts to these younger generations, the adoption of technologies that promote natural cattle behaviors may be one means toward reconciling the disconnect between public perceptions of animal welfare and contemporary dairy farming practices.

Automated detection of estrous behavior in tie-stall housing using a barometer and accelerometer.

Tie-stall housing inhibits movement in cows, thereby restricting the behavioral indicators used by farmers for detecting estrous. In this study, we investigated the changes in patterns of lying and standing times at estrous, and evaluated the potential for automated detection of estrous within tie-stalls using a barometer and accelerometer. On estrous days, total daily standing time was significantly longer than that during non-estrous days (P < 0.05). A practical method was developed for detecting slight altitude changes using a novel device, which consisted of a barometer and accelerometer, and was attached to the neckband. Total daily standing time predicted using this new device was found to be highly correlative with the observed measured data (r = 0.95, P < 0.01), indicating the accuracy of the device in measuring daily standing time in tie-stall housed cows. In addition, the device detected an overall increase in total daily standing time during estrous days.

Prevalence of lameness and associated risk factors on dairy farms in the Maritime Provinces of Canada.

Lameness in dairy cattle is a major issue for the industry due to the effects on the welfare of the animal, the economic impact, and consumer perception. The aim of this study was to determine the prevalence of lameness and explore potential risk factors in the Maritime Provinces of Canada. Cows were scored for lameness and potential risk factors and were assessed in 46 freestall herds and 33 tiestall herds in Nova Scotia, New Brunswick, and Prince Edward Island. In freestall herds, lameness was assessed using the most common method, locomotion scoring. A cow with a gait score of ≥3 out of 5 was considered to be lame. In tiestall herds, lameness was assessed using an alternative method known as stall lameness scoring. This assessment consisted of observation of the cow for 4 behavioral changes: standing on the edge of the stall, shifting weight, resting a limb, and uneven weight bearing when moved side to side. A cow displaying 2 or more of these behaviors was considered to be lame. At the time of the assessment, other animal-, environmental-, and management-based measurements were collected. These measurements were used in multivariable logistic regression analysis to determine risk factors that were associated with lameness for both freestalls and tiestalls independently. The prevalence of lameness was 21% for freestall-housed cattle and 15% for tiestall-housed cattle. Of the 1,488 tiestall-housed cows that were assessed, 68% showed no behavioral changes, whereas 15, 15, 2, and <1% showed 1, 2, 3, or 4 changes, respectively. In freestalls, higher odds of lameness were seen when cows spent ≥3 h/d in the holding area for milking compared with those that spent <3 h/d. In tiestall herds, higher odds of lameness were seen when bedding material was wet compared with when it was dry. For both lactating cow facility types, housing the dry cows and heifers on a deep bedded pack compared with tiestalls or freestalls was associated with a decreased odds of lameness. There were also many cow-level variables associated with lameness, including parity, daily milk production, stage of production, body condition, and width at the tuber coxae (hook bones). If producers become aware of the risk factors associated with lameness, they can make informed decisions on where to implement changes to help reduce the level of lameness in their herd.

Prevalence of hock, knee, and neck skin lesions and associated risk factors in dairy herds in the Maritime Provinces of Canada.

Skin lesions are commonly seen in dairy herds and have been associated with animal-, environmental-, and management factors. These lesions are not only a welfare concern, but they also affect profitability. Three areas on the cattle were examined for skin lesions: the hock, knee, and neck. Previous Canadian studies estimating the prevalence of lesions and the risk factors associated with them have not included the Maritime Provinces. In this study, 73 herds in the Maritime Provinces were chosen voluntarily to participate, with both tiestalls (n = 33) and freestalls (n = 40) represented. Within each herd, 67 to 90% of the lactating cows were selected and assessed for potential animal-, environmental-, and management-based risk factors. If producers were aware of the potential risk factors, this could help them reduce the prevalence in their herd. Leg lesions were scored on a 4-point scale (0-3) based on hair loss, swelling, and scabs, with a lesion defined as a score of 2 or 3 on at least 1 hock or knee. Necks were scored on a 3-point scale (0-2), with a lesion defined as score 2. For freestalls, the prevalence (95% confidence interval) of hock lesions was 39% (29-49%), knee lesions was 14% (11-18%), and neck lesions was 1% (<1-2%). Similarly, for tiestalls the prevalence (95% confidence interval) of hock lesions was 39% (33-46%), knee lesions was 17% (13-22%), and neck lesions was 5% (3-8%). Due to differences in management and methods of assessment between facility types, tiestalls and freestalls were analyzed separately. Due to dichotomization of cows as having a skin lesion or not, random-effects multivariable logistic regression was used to determine the risk factors for each lesion and facility type. Several environmental-based measurements, such as the stall base, type and dryness of bedding, and type of milking parlor, were associated with leg lesions. An environmental-based measurement that was associated with neck lesions was the design of the feed rail barrier in freestalls and the dimensions of the tie rail in tiestalls. Animal-based risk factors, such as stage of lactation, parity, and body condition, were also associated with all 3 types of lesions. This study showed that lesions to the hock, knee, and neck were common in the Maritime Provinces of Canada. Although differences were seen between facility types, in general, the results suggest that improving stall design and management and feed bunk design would help producers reduce the number of skin lesions seen in dairy cattle.

Associations between on-farm cow welfare indicators and productivity and profitability on Canadian dairies: II. On tiestall farms.

The use of tiestall housing for dairy cows is often criticized due to the reduced freedom of movement it offers for the animals. Maximizing comfort is especially important in tiestall farms to ensure an acceptable level of cow welfare. Motivating dairy producers to make financial investments directly aimed toward the improvement of their animals' welfare can be challenging, especially when financial returns are uncertain. The aim of this study was to evaluate the existence of associations between on-farm animal welfare and indicators of farm productivity and profitability in tiestall farms. The prevalence of animal-, resource-, and management-based welfare indicators was collected on 100 Canadian tiestall farms during a cow comfort study. Records from the dairy herd improvement agency were retrieved and used to calculate the farms' productivity and profitability measures. Univariable and multivariable linear regressions were used to assess the associations between welfare indicators and milk production, milk quality, cow longevity, and economic margins calculated over replacement costs. Increased yearly average corrected milk production was associated with longer average lying time [ß = 272; 95% confidence interval (CI): 94, 450] and a higher proportion of cows fitting the tie-rail height (ß = 6; 95% CI: 1, 11). Lower yearly average somatic cell count was associated with lower percentages of stalls mostly soiled with manure (ß = -3.7; 95% CI: -1.9, -5.4) and a lower proportion of cows with body condition score ≤2 (ß = -5.1; 95% CI: -2.3, -8.3). The average margin per cow over replacement costs was positively associated with average lying time (ß = 147; 95% CI: 27, 267), percent of stall not soiled with manure (ß = 7.2; 95% CI: 3.0, 11.3), and the frequency of scheduled hoof trimming per year. Some of the relationships found included interactions between animal- and management-based welfare measures. For example, the relationship between lameness prevalence and average milk production was modified through the milk production genetic index. Overall, the results show that improved cow comfort and welfare on tiestall farms is associated with increased productivity, cow longevity, and profitability when estimated through margins calculated over the replacement costs. Producers should aim to optimize all aspects of stall comfort to enhance their cows' productivity.

Is the profitability of Canadian tiestall farms associated with their performance on an animal welfare assessment?

In order for dairy producers to comply with animal welfare recommendations, financial investments may be required. In Canada, a new dairy animal care assessment program is currently being implemented under the proAction Initiative to determine the extent to which certain aspects of the Code of Practice are being followed and to assess the care and well-being of dairy cattle on farm. The aim of the current study was to evaluate the association between meeting the proAction animal-based and the electric trainer placement criteria and certain aspects of productivity and profitability on tiestall dairy farms. The results of a previous on-farm cow comfort assessment conducted on 100 Canadian tiestall farms were used to simulate the results of a part of the proAction Animal Care assessment on these farms. Each farm's productivity and profitability data were retrieved from the regional dairy herd improvement associations. Univariable and multivariable linear regressions were used to evaluate the associations between meeting these proAction criteria and the farms' average yearly: corrected milk production, somatic cell count (SCC), calving interval, number of breedings/cow, culling rate, prevalence of cows in third or higher lactation, and margins per cow and per kilogram of quota calculated over replacement costs. The association between milk production and the proAction lameness criterion was moderated through an interaction with the milk production genetic index which resulted in an increase in milk production per year with increasing genetic index that was steeper in farms that met the proAction lameness criterion compared with farms that did not. Meeting the proAction body condition score criterion was associated with reduced SCC and meeting the proAction electric trainer placement criterion was associated with SCC through an interaction with the farms' average SCC genetic index. The increase in SCC with increasing SCC genetic index was milder in farms that met this criterion compared with farms that did not. Farms that met the proAction electric trainer placement criterion had 4.6% more cows in their third or greater lactation. These results suggest that some associations exist between the productivity of Canadian tiestall farms and meeting several parameters of the proAction Animal Care assessment. Meeting these criteria is unlikely to impose any economic burden to the dairy industry as a whole.

Technical note: Assessing lameness in tie-stalls using live stall lameness scoring.

Video stall lameness scoring (SLS) has been shown to be comparable to video locomotion scoring for evaluating lameness in dairy cows housed in tie-stalls and may be a more practical and easier method to measure lameness in a herd. We compared live SLS to video SLS and to live locomotion scoring. A total of 685 lactating cows subsampled from 27 commercial dairy herds were examined for lameness through live and video SLS. Cows scored with the live or video SLS system were scored for 4 behavioral indicators while still in their stall: weight shifting (shift), standing on the edge of the stall (edge), uneven weight bearing while standing (rest), and uneven weight bearing while moving from side to side (uneven). Two observers live scored and video scored for SLS. Lameness prevalence from video SLS and live SLS were similar (31 vs. 30%, respectively). Prevalence of the behavioral indicators varied from 0.59 to 58.2%. Sensitivity and specificity of live SLS was calculated using video SLS as the gold standard for lameness detection in tie-stalls. Sensitivity of live SLS was 0.83 and specificity was 0.94. False positives and false negatives for lameness were 14.4 and 16.8%, respectively. When comparing the prevalence of lameness measured through video or live SLS at the herd level, live SLS for lameness was correlated to video SLS (r = 0.91) with a Cohen's kappa coefficient of 0.79 (95% confidence limit = 0.73-0.84). Average exact agreement in the behavior indicators observed ranged from 80 to 100%. A subsample of 250 cows from 5 herds were scored for live SLS and live locomotion by a third observer. Intra- and interobserver reliability for live SLS and live locomotion scoring were found to have a kappa coefficient of 0.53 (95% confidence limit = 0.43-0.64) when determining a cow as lame through SLS or locomotion scoring. Live SLS was correlated with live locomotion scoring (r = 0.92). However, lameness prevalence was lower when using live SLS (28.4%) compared with locomotion scoring (38%). In summary, live SLS may be an acceptable method to replace video SLS to identify lame cows and rank tie-stall herds in terms of lameness prevalence without having to remove the cows from their stalls or view videos to score; however, it may underestimate lameness prevalence compared with locomotion scoring methods.

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.

Producer estimates of prevalence and perceived importance of lameness in dairy herds with tiestalls, freestalls, and automated milking systems.

Lameness is one of the most important welfare and productivity concerns in the dairy industry. Our objectives were to obtain producers' estimates of its prevalence and their perceptions of lameness, and to investigate how producers monitor lameness in tiestall (TS), freestall with milking parlor (FS), and automated milking system (AMS) herds. Forty focal cows per farm in 237 Canadian dairy herds were scored for lameness by trained researchers. On the same day, the producers completed a questionnaire. Mean herd-level prevalence of lameness estimated by producers was 9.0% (±0.9%; ±SE), whereas the researchers observed a mean prevalence of 22.2% (±0.9%). Correlation between producer- and researcher-estimated lameness prevalence was low (r = 0.19) and mean researcher prevalence was 1.6, 1.8, and 4.1 times higher in AMS, FS, and TS farms, respectively. A total of 48% of producers thought lameness was a moderate or major problem in their herds (TS = 34%; AMS =53%; FS = 59%). One third of producers considered lameness the highest ranked health problem they were trying to control, whereas two-thirds of producers (TS = 43%; AMS = 63%; FS = 71%) stated that they had made management changes to deal with lameness in the past 2 yr. Almost all producers (98%) stated they routinely check cows to identify new cases of lameness; however, 40% of producers did not keep records of lameness (AMS = 24%; FS = 23%; TS = 60%). A majority (69%) of producers treated lame cows themselves immediately after detection, whereas 13% relied on hoof-trimmer or veterinarians to plan treatment. Producers are aware of lameness as an issue in dairy herds and almost all monitor lameness as part of their daily routine. However, producers underestimate lameness prevalence, which highlights that lameness detection continues to be difficult in in all housing systems, especially in TS herds. Training to improve detection, record keeping, identification of farm-specific risk factors, and treatment planning for lame cows is likely to help decrease lameness prevalence.

Prevalence of and risk factors for hock and knee injuries on dairy cows in tiestall housing in Canada.

Leg injuries on dairy cows are a common and highly visible welfare concern on commercial dairy farms. With greater attention being placed on food animal welfare and limited research being conducted on tiestall farms, this study aimed to identify prevalence and risk factors for hock and knee injuries on dairy cows housed in tiestall barns in Ontario (n=40) and Quebec (n=60). A sample of 40 cows was purposively selected per farm and several animal- and farm-based measures were taken. Both hocks and both knees on each cow were scored as injured (presence of lesions or swelling) or not injured (no alterations or hair loss), and the highest score of each of the 2 knees and the 2 hocks was considered the cow's hock or knee score. Possible animal- and farm-based risk factors were incorporated into 2 separate multivariable logistic models for hock injuries and knee injuries respectively at the cow level. Mean (±SD) percentage of cow with hock injuries per farm was found to be 56±18% and mean percentage of knee injuries per farm was found to be 43±23%. Animal-based factors found to be associated with a greater odds of hock injuries at the cow level were increased days in milk (DIM), lower body condition score (BCS), lameness, higher parity, higher cow width, median lying bout duration, and median number of lying bouts. Environmental factors found to be associated with hock injuries at the cow level were province, stall width, tie rail position, stall base, chain length, and age of stall base. Animal-based factors found to be associated with knee injuries at the cow level were DIM, BCS, and median lying time. Environmental factors found to be associated with knee injuries at the cow level were stall width, chain length, province, stall base, and bed length. Quadratic and interaction terms were also identified between these variables in both the hock and knee models. This study demonstrates that hock and knee injuries are still a common problem on tiestall dairy farms in Canada. Several animal- and housing-based factors contribute to their presence. Further research to confirm causal relationships between these factors would help identify the cause of knee and hock injuries and determine how to best reduce the incidence of injuries in cows on commercial tiestall dairy farms in Canada.

An assessment tool to help producers improve cow comfort on their farms.

Effective management and an appropriate environment are essential for dairy cattle health and welfare. Codes of practice provide dairy producers with best practice guidance for the care and handling of their cattle. New Canadian recommendations have been established for the dairy industry. The objectives of this study were to develop an on-farm assessment tool that helps producers assess how well they are meeting their code of practice and that identifies management and environment modifications that could improve dairy cow comfort on their farms. The assessment tool addressed critical areas of dairy cow comfort, including accommodation and housing (stall design, space allowance, stall management, pen management, milking parlor, and transfer alleys), feed and water (body condition scoring, nutrition), and health and welfare (lameness, claw health, and hoof-trimming). Targets of good practices were identified from the requirements and recommendations of the code of practice. Each farm received a score for each target, ranging from 0 (target not reached) to 100 (target reached). One hundred tiestall and 110 freestall farms were surveyed in 3 provinces of Canada (Quebec, Ontario, and Alberta). The duration of the assessment, in 2 visits lasting, on average, 8 and 9h (range between freestall and tiestall farms) and 4 and 4.1h, was beyond the targeted 3 to 4h due mainly to the animal-based measures; strategies to reduce the duration of the assessment were discussed. Standard operating procedures were developed to ensure consistency in measuring and recording data. Periodical checks were conducted by trainers to ensure all 15 assessors remained above target agreement of weighted kappa ≥0.6. Average scores for all critical areas ranged from 25 to 89% for freestall farms and from 48 to 95% for tiestall farms. These scores need to be considered with caution when comparing farms because scores could not always be calculated the same way between housing systems. An evaluation report was provided and discussed with each producer, identifying strengths and areas for improvement that could benefit dairy cow comfort on their farms. The producers were convinced of the effectiveness of our tool for assessing cow comfort (freestall: 86%; tiestall: 95%) and in assisting them to make decisions for improvements (freestall: 83%; tiestall: 93%). Our cow comfort assessment tool served as background material for the Dairy Farmers of Canada animal care assessment program.

Technical note: a comparison of 2 methods of assessing lameness prevalence in tiestall herds.

We compared 2 methods for identifying lame cows and estimating the prevalence of lameness in tiestalls. Cows (n=320) in 9 tiestall herds were scored as lame both by the presence of limping while walking and by stall lameness scores (SLS). The SLS was based on the number of the following behaviors that the cow showed while standing in the tiestall: weight shifting, standing on the edge of the stall, uneven weight bearing while standing, and uneven weight bearing while moving from side to side. Two observers watched video-recordings of the cows. Intraobserver agreements for the 4 SLS behaviors ranged from 92 to 100%, and interobserver agreement ranged from 81 to 100%. The overall prevalence of lameness based on an SLS of ≥2 was similar to that of limping (39 vs. 40%). The sensitivity of the classification based on the SLS was 0.63 and the specificity was 0.77 in identifying cows with a limp; accuracy varied across farms from 62.2 to 80.4%, with a mean of 71.7%. A cow with an SLS of ≥2 had 4.88 times the odds of limping than a cow with an SLS of <2. The prevalence of lameness on farms based on SLS was highly correlated with the prevalence of limping (Pearson correlation=0.88; n=9), and prevalence estimates from the 2 methods diverged most when the mean herd prevalence was lower. The SLS method provides an estimate of the prevalence of lameness in tiestall herds comparable with traditional gait scoring, but does not require that the cows be untied. The SLS method could be used to improve lameness detection on tiestall farms and obtain estimates of lameness prevalence without the need to walk the cows.

Factors at Insemination and Subsequent Conception of Cattle under Heat-Stress Tie-Stall Environments.

This research aimed to compare the conception rates among AI at 12, 24, and 36 h after estrus in cattle living in tie-stall barns in a tropical environment. The second study was to determine factors at insemination at 24 h after estrus, including secondary signs of estrus behavior, reproductive tract characteristics, and heat-stress factors, in relation to conception. The study was conducted on 22 tie-stall dairy farms in Chiang Mai, Thailand. After secondary signs of estrus were observed, all farmers were informed for data collection at the insemination time. Repeated logistic regression models were used to determine factors associated with conception. The results revealed that cattle inseminated 24 h after estrus detection had the highest conception rate (67.5%). The study also found that cattle with three or two secondary estrus signs before insemination had a higher risk of conception than those with only one sign. Interestingly, there was an increased risk of conception when sticky or no cervical mucus was observed during insemination (OR = 6.85 and OR = 5.96, respectively). Moreover, increases in body temperature and ambient relative humidity were related to a decrease in the chances of conception. This study recommends delaying insemination to 24 h after the initiation of secondary estrus signs. Multiple signs of estrus, sticky cervical mucus, and lower body temperature increased conception risk in dairy cattle living in tie-stall barns in a heat-stress environment.

Effects of Heat Stress in Dairy Cows Raised in the Confined System: A Scientometric Review.

Due to climate change, heat stress is a growing problem for the dairy industry. Based on this, annual economic losses in the dairy sector are verified mainly on a large scale. Despite several publications on thermal stress in lactating dairy cows in confinement systems, there need to be published reviews addressing this issue systematically. Our objective was to scientometrically analyze the effects of heat stress in dairy cows managed in a confinement system. Based on PRISMA guidelines, research articles were identified, screened, and summarized based on inclusion criteria for heat stress in a confinement system. Data was obtained from the Web of Science. A total of 604 scientific articles published between 2000 and April 2022 were considered. Data was then analyzed using Microsoft Excel and CiteSpace. The results pointed to a significant increase in studies on heat stress in lactating cows housed in confinement systems. The main research areas were Agriculture, Dairy Animal Science and Veterinary Sciences. The USA showed the highest concentration of studies (31.12%), followed by China (14.90%). Emerging themes included heat stress and behavior. The most influential journals were the Journal of Dairy Science and the Journal of Animal Science. The top authors were L. H. Baumgard and R. J. Collier. The leading institutions were the Chinese Academy of Agricultural Sciences, followed by the State University System of Florida and the University of Florida. The study maps the significant research domains on heat stress of lactating cows in confinement systems, discusses implications and explanations and highlights emerging trends.

Brain-Derived Neurotrophic Factor, Kynurenine Pathway, and Lipid-Profiling Alterations as Potential Animal Welfare Indicators in Dairy Cattle.

Complete animal welfare evaluation in intensive farming is challenging. With this study, we investigate new biomarkers for animal physical and mental health by comparing plasma expression of biochemical indicators in dairy cows reared in three different systems: (A) semi-intensive free-stall, (B) non-intensive tie-stall, and (C) intensive free-stall. Additionally, protein levels of mature brain-derived neurotrophic factor (mBDNF) and its precursor form (proBDNF) and indoleamine 2,3-dioxygenase (IDO1) specific activity were evaluated in brain samples collected from 12 cattle culled between 73 and 138 months of age. Alterations in plasma lipid composition and in the kynurenine pathway of tryptophan metabolism were observed in the tie-stall-reared animals. The total plasma BDNF concentration was higher in tie-stall group compared to the two free-housing groups. Brain analysis of the tie-stall animals revealed a different mBDNF/proBDNF ratio, with a higher level of proBDNF (p < 0.001). Our data are similar to previous studies on animal models of depression, which reported that inhibition of the conversion of proBDNF in its mature form and/or elevated peripheral kynurenine pathway activation may underlie cerebral biochemical changes and induce depressive-like state behavior in animals.

Comparison of Cattle Housing Systems Based on the Criterion of Damage to Barn Equipment and Construction Errors.

Dairy cattle housing systems are the subject of numerous studies, in which a strong emphasis is placed on the comparison of animal welfare, animal behavior, production indicators and labor inputs. Dairy cattle housing systems are linked to specific livestock buildings, which is a prerequisite for undertaking studies comparing barns and their technical equipment. The aim of the study was to compare barns with two types of housing systems, i.e., tie-stall and freestall, including the identification of technical wear in various areas used by animals. This objective was linked to the assessment of animal health problems in livestock facilities. The research covered 38 dairy farms, 19 of which kept cows in the tie-stall system and 19 in the freestall system. The barns in these farms were examined for technical damage and construction errors, assessed in four areas: lying, feeding, milking and social. The research results confirmed significant differences in the degree of damage to technical equipment in individual areas of barns and between barns with tie-stall and freestall housing systems. The conclusions indicate the need to link the degradation of barns and their technical equipment, as well as design errors with the evaluation of dairy cattle welfare in future studies.

Estrus Detection Using Background Image Subtraction Technique in Tie-Stalled Cows.

In this study, we determined the applicability of the background image subtraction technique to detect estrus in tie-stalled cows. To investigate the impact of the camera shooting direction, webcams were set up to capture the front, top, and rear views of a cow simultaneously. Video recording was performed for a total of ten estrous cycles in six cows. Standing estrus was confirmed by testing at 6 h intervals. From the end of estrus, transrectal ultrasonography was performed every 2 h to confirm ovulation time. Foreground objects (moving objects) were extracted in the videos using the background subtraction technique, and the pixels were counted at each frame of five frames-per-second sequences. After calculating the hourly averaged pixel counts, the change in values was expressed as the pixel ratio (total value during the last 24 h/total value during the last 24 to 48 h). The mean pixel ratio gradually increased at approximately 48 h before ovulation, and the highest value was observed at estrus, regardless of the camera shooting direction. When using front-view videos with an appropriate threshold, estrus was detected with 90% sensitivity and 50% precision. The present method in particular has the potential to be a non-contact estrus detection method for tie-stalled cows.