Calf Housing Research Articles

Study on the causes of calf morbidity and mortality and its associated risk factors in South Omo Zone, South-Western Ethiopia

A cross-sectional and longitudinal observational study with the objectives to identify calf management and husbandry practices and to investigate the major causes of calf morbidity and mortality and its associated risk factors was conducted in South Omo Zone from 2015 to 2016. A total of 85 calf owners were interviewed and 255 calves of those farmers were longitudinally followed for six months from the very first day of their birth. Accordingly, retained placenta 17/85 (20%), narrow pelvic outlet 17/85 (17.6%) and prolonged labour 8/85 (9.4%) were ranked as maternal-related calving problems whereas, ‘navel ill’ 34/85 (40.0%), dead birth 9/85 (10.6%), oversized calve 16/85 (18.8%) and abnormal presentation 9/85 (10.6%) were identified as calf-related problems. The traditional healers 31/85 (36.47%) and veterinarians 24/85 (28.23%) were dominant calving assistants in the study areas. Moreover, bloody diarrhea 24/85 (28.2%), ectoparasites 10/85 (11.8%), pneumonia 7/85 (8.2%) and constipation 3/85 (3.5%) were categorized as the major health problems that frequently affected the calves. From the calves longitudinally followed, 85 calves (33.3%) were encountered different health problems which resulted in calf morbidity and mortality. Identified health problems were not significantly associated (p>0.05) with study sites, sex and breed of calves. According to multiple logistic regression analysis, six variables (calf housing system, dam vaccination history, colostrum feeding frequency, calf house clearing frequency, parity of the dam and calf delivery problem) were significantly associated (p<0.05) with calf morbidity. However, none of the variables was significantly associated with calf mortality. Through six months follow-up, 4.41% crude calf mortality rate was recorded. Sudden death with unknown cause, bloody diarrhea, pneumonia, “evil eye” and physical damages were responsible for 36.36, 18.18, 18.18, 9.09 and 18.18% case fatality and responsible for 1.60, 0.80, 0.80, 0.40 and 0.80% crude mortality respectively. The crude mortality varies among sex; 3.13 and 6.67% respectively in male and female calves. Similarly, it was relatively higher in calves under one week of age (5.73%) and decreasing as the calf’s age increased. It can be concluded that improving herd management and husbandry practices which negatively affecting calf health could minimize calf morbidity and mortality. Moreover, improving the whole herd health system and awareness creation to calve owners to improve the dynamism of their future replacement calve is very important in this area.

Incidences of Calf Diarrhea and the Associated Risk Factors in Ivory Coast (2015-2017)

Diarrhea is the most important disease of neonatal calves, and it results in the greatest economic losses. A longitudinal observational study was conducted from September 2015 to October 2017. This study proposes to investigate the incidence of diarrhea in calves and their mortality rate so as to identify potential risk factors related to the occurrence of calf diarrhea on 372 farms in the regions of Abidjan, Bouake, Bondoukou, and Korhogo in Ivory Coast. Information on potential risk factors was collected based on personal observations from regular visits to the farms and from a survey conducted during the period of the study. A total of 2020 calves under the age of three months were selected. Only 347 (17.17%) of the 2020 calves showed signs of diarrhea. The overall mortality rate was 0.39%. Based on the survey, colostrum feeding, the calf’s age and sex, calf housing, seasonal variation, the calving period, environment conditions, the ignorance of herdsmen, and management systems were found to be the major risk factors for gastroenteritis in calves. Calves reared in an extensive system were less susceptible to neonatal diarrhea. The calf health and management issues found in this study can be resolved by creating awareness among farm owners and implementing better calf management practices and cattle vaccination programs.

Hygiene management in newborn individually housed dairy calves focusing on housing and feeding practices.

In calf rearing, the first weeks of life are critical and associated with the highest mortality due to enteric and respiratory diseases. A well-implemented hygiene management can help to protect calves' health preventively by reducing the load of pathogenic bacteria and interrupting infection chains. The aim of this study was to identify deficiencies in hygiene management of individually housed dairy calves by surveying current practice and examining feeding and housing equipment with different hygiene indicators. On 11 farms, different locations in 2 pens or hutches for individual calf rearing prepared for restocking and 2 feeding buckets per farm, including the inner and outer surfaces of artificial teats, were visually scored for cleanliness and sampled with swabs (housing equipment: n = 167; feeding equipment: n = 120). The sanitation of floors was tested with sock samples (n = 41). A total of 328 samples were analyzed for adenosine triphosphate (ATP) and protein residues, aerobic total viable count (TVC), total coliform count (TCC), Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum β-lactamase-producing bacteria (ESBL), and Salmonella spp. After evaluation of these results, the farmers were informed about the findings and trained on improvement in hygiene management personally. The sampling was repeated after 1 year to detect possible changes in hygiene management. The highest bacterial loads (TVC, TCC, and E. coli) were observed in feeding equipment, especially the inner teat of milk feeding buckets. Environmental samples, primarily the sidewalls and back walls of tested pens and hutches, exhibited the lowest bacterial counts and ATP and protein residues. All samples were negative for MRSA and Salmonella spp. In 10.5% of all samples, ESBL was detected, and in 6.8%, ESBL E. coli was detected, predominately in sock samples, followed by feeding equipment samples. Training in hygiene management showed only limited effects. In conclusion, there is still great potential to improve the implementation of hygiene measures in individual calf housing. In particular, more attention should be paid to the cleaning of feeding buckets and artificial teats, as this is a simple means of interrupting the possible spread of pathogens among calves.

Determinants of Household Choice of Dairy and Plant-based Milk Alternatives: Evidence from a Field Survey

ABSTRACT The growing popularity of plant-based milk alternatives suggests a shift in consumer preferences for dairy and nondairy products. Drivers of these shifts include rising concerns for environmental sustainability and farm animal welfare (FAW). Using data from a field survey, this study examines how primary purchasing motivations regarding health, nutrition, environment, and FAW worldviews (a focus on perceptions of calf housing) influence consumer choice of dairy milk, plant-based milk alternatives, and soda. We also explore parent–child consumption patterns within a given household. Our results show that as compared to the baseline of price sensitive consumers, respondents who were primarily concerned about health, FAW, and the environment were more likely to purchase and consume plant-based milk alternatives more frequently. We find consistencies in the consumption patterns between youth and parents within households; however, the substitution effects of FAW worldviews on these consumption patterns differed. The implications of these findings for the fluid milk industry are discussed.

Energy-efficient thermoelectric unit for microclimate control on cattlebreeding premises

The microclimate control for animals is the mandatory condition of ecological compatibility of agricultural industry and production of high-quality products, protection of both the animals and products and, hence, people who consume such products from the harmful influence of technical progress. The goal of research was to develop an air dehumidifier based on Peltier elements for ensuring optimal microclimate parameters on cattle breeding premises. Advantages notwithstanding, there are no Peltier element-based dehumidifiers for such conditions. The functional–technological scheme and method for calculating the parameters of the thermoelectric installation for dehumidifying, heating and disinfecting the air in livestock buildings are presented. The parameters and modes of its operation are substantiated. The results of physical simulations of air dehumidification and heating processes are reported. The design structure of the thermoelectric unit’s operating sample and the results of its testing are presented. As a result of the research, it was found out that the thermal energy extracted by the hot circuit and used to heat the dehumidified air exceeds the electric energy consumed from the power grid by 20% to 30%. The use of the proposed units instead of traditional ones will enable the consumer to reduce his energy costs by a maximum of 30%. The dehumidifiers are designed for application on agricultural premises of small volume characterized by required air capacity of about 500 m3/h, such as maternity rooms, prophylactorium calf houses, veterinary sanitary centers, etc. The research performed allows to create a typical size spectrum for dehumidifiers within the specified range of capacity. For their application on cattle breeding premises where a high air capacity is required, additional research is needed. The price of developed thermoelectric dehumidifier of power up to 5 kW and air capacity of up to 500 m3/h (600−700 $) is comparable with that of conventional air dehumidifiers. The estimated annual economic effect of this equipment introduction into a commercial dairy farm for 800 livestock units will be circa $9000.

Relationships of Some Husbandry Practices with Calf Loss Rate in Dairy Farms: A Case Study of Alacam County of Samsun Province

In this study, the relationships between some husbandry practices and calf losses in dairy farms were investigated. A total of 39 farms enrolled to Alacam Cattle Breeders Association (CBA) of Samsun, Turkey, were evaluated by structural factors (education level of farm owner: EL, personnel number: PN, experience of farm owner: EF and number of cows: NC) and husbandry practices (individual calf housing: ICH, calving pen: CP and weaning period: WP). The questionnaires for interview, observations on farm level and records of CBA belonging to 2018 and 2019 were examined. While no significant difference was found among the all groups, dead calf per farm (0.64±0.25) and mean of calf loss rate (CLR) per farm (3.42±1.07%) were assumed within the acceptable thresholds. Presenting more attention on calf rearing methods was suggested to be diminishing approach to decrease the calf mortality in the farms.

Physiological responses of Holstein calves to hot weather conditions.

The objectives of the study described were to (1) compare environmental temperature-humidity index (THI) with the THI measured within two different calf housing systems and (2) determine how THI affects Holstein heifer calf body temperatures, serum cortisol concentrations, and serum thyroxine concentrations. At 24 to 48h of age, calves were assigned to one of two individual housing treatments: (1) stalls in a three-sided barn (n = 8) or 2) hutches placed outside (n = 8). Calves were observed until 42days of age during the summer months. Ambient temperature and relative humidity within housing systems were recorded hourly. Calf body temperatures were measured hourly using devices attached to the underside of each calf's tail. Blood samples were collected at 7, 21, and 42days of age via jugular venipuncture. Blood serum was analyzed for cortisol and thyroxine concentrations using enzyme-linked immunosorbent assays (ELISAs). Overall average THI was higher in hutches than in stalls (P < 0.0001). Calves housed in hutches had higher body temperatures (39 ± 0.18°C vs 38 ± 0.15°C, P = 0.005). No differences occurred in serum cortisol concentrations (P = 0.89) but at 21days of age, calves housed in hutches had higher serum thyroxine concentrations (16.55 ± 0.51μg/dl vs 13.91 ± 0.54μg/dl, P = 0.0006) than calves housed in stalls. Although both housing systems in this study were located on the same dairy, calves housed in hutches were exposed to higher THI values, had higher body temperatures, and at 21days of age had higher serum thyroxine concentrations than calves housed in stalls inside a three-sided barn.

Youth and adult public views of dairy calf housing options

The objective of this study was to explore views on dairy calf housing options among American youth and adults. Youth views were of interest because they are future consumers, yet their influence on livestock production practices is often overlooked. Participants 5 to 17 yr of age (n = 463) and 18 yr or older (n = 1,310) completed an in-person survey at the Minnesota State Fair (St. Paul, MN) in summer 2018. The survey was administered via Qualtrics survey software (Qualtrics, Provo, UT) using iPads (Apple, Cupertino, CA) and, in addition to collecting demographics, presented 3 images of calf housing options (individual, pair, or group) and asked participants to select their preferred option and indicate their reasoning for selection (youth), or acceptance for each option and reasoning for selection (adult). The PROC SURVEYFREQ of SAS (9.4; SAS Institute Inc., Cary, NC) was used for descriptive analysis. Rao-Scott chi-square tests (PROC SURVEYFREQ, SAS 9.4) were used to investigate relationships between demographics and housing preference or acceptance. Content analysis identified recurring themes to describe qualitative reasoning underlying dairy calf housing preference or acceptance. The median age of youth participants was 11 yr, 61% were female, 82% were urban residents, and 63% did not have prior experience handling agricultural animals, but 83% had visited a farm in the past. Median age range of adult participants was 45 to 54 yr, 65% were female, 82% urban residents, 41% completed a bachelor's degree, and 81% did not have prior experience handling agricultural animals, but 63% had visited a farm in the past. Overall, group housing was overwhelmingly preferred by youth participants (80.1%), followed by pair (14.3%) and individual housing (5.6%). Youth who chose group housing most commonly cited reasons related to increased socialization (71.4%) and space allowance (58.5%). Housing preference of youth was not associated with age, gender, or prior visits to a farm. However, rural youth more frequently preferred individual housing compared with urban youth (13.6 ± 4.5% SE vs. 5.1 ± 1.3%, respectively). Similarly, adult participants were most accepting of group housing for dairy calves (75.8% of participants), with reasons focused on calves' ability to socialize and access to increased space allowance. Adult males, rural residents, and individuals with previous livestock handling experience more frequently accepted individual calf housing compared with females, urban residents, and individuals without previous livestock handling experience. These findings suggest that housing systems that enable greater degrees of behavioral freedom for calves may be more socially sustainable for the dairy sector.

Influence of temperature and humidity on the dynamics of aerosol numbers and airborne bacteria in a dairy calf house

Aerosols are essential indicators of indoor air quality in livestock houses. An investigation was conducted in a dairy calf house into the relationships between the concentration of aerosol number and the concentrations of the airborne aerobic bacteria, Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Salmonella spp. examining their dependence on air temperature and relative humidity (RH). The aerosol number concentration and the concentrations of airborne aerobic bacteria, S. aureus, E. coli, and Salmonella spp. in the indoor air were monitored over 19 weeks, in Tochigi, Japan. A significant positive relationship was found between the concentration of airborne aerobic bacteria with aerosol sizes 0.3–5.0 μm and 0.5–1.0 μm and Salmonella spp. No relationship was found among the different sizes of aerosol concentration with airborne S. aureus or E. coli concentrations. The most significant positive relationships with temperature and RH were found with the 0.3–5.0 μm aerosol size range. Aerosol sizes 5.0–10.0 μm showed no associations with either air temperature or RH. Both airborne aerobic bacteria and S. aureus were strongly positively related to temperature. These findings will play a crucial role in elucidating the role of aerosols in the transmission of different types of airborne bacteria, and ultimately this could play an essential part in mitigating the influence of aerosols in the transmission of airborne bacteria in dairy houses.

Pre-weaning management of calves on commercial dairy farms and its influence on calf welfare and mortality

Welfare and management of calves is of increasing interest and also influences performance of these animals in later life. The aim of this study was to assess management and environmental conditions under which pre-weaned dairy calves are reared on commercial Irish dairy farms. We included 47 spring-calving, pasture-based herds in this study. Herd and animal-specific data, such as mortality rate, age and breed, were gathered from all participants via the HerdPlus® database. Information pertaining to management practices was collected by conducting an interview with the principal calf rearer, while an assessment of calf housing facilities was conducted to identify conditions calves were reared in. The environmental assessment included measurements of space allowance per calf, as well as feeding equipment hygiene. To assess calf behaviour video observations were used, while accounting for the number of calves present in a group and the space available per calf. Faecal samples were also collected to determine the presence of enteric pathogens among calves. To compare calf space allowance, group size and presence of enteric pathogens early and late in the calving season each farm was visited twice. Calf mortality was not associated with either herd size, space allowance per calf or post-colostrum feeding practices. Higher calf mortality was identified among herds which reported experiencing an on-set of calf pneumonia during weeks 8 to 10 of the calving season. This study demonstrates that factors associated with calf welfare on commercial Irish dairy farms (e.g. space allowance, mortality rate) are independent of herd size. Some management practices however, such as methods used for treating health issues can affect rates of calf mortality experienced. Calf mortality, for example, was lower in herds which treated diarrhoea cases by administering electrolytes, while continuing to offer milk. Behavioural observations indicate that smaller group sizes could promote expression of positive behaviours, potentially resulting from an overall improvement in welfare. Space allowance per calf was not associated with observed behaviour frequencies. We also identified that similar rates of calf mortality are experienced across herds of different sizes.

Relationships Between Aerosol Particles and Airborne Bacteria and their Dependence on Environmental Factors in a Dairy Calf House

Abstract. The quality of indoor air dramatically affects the health of animals and humans. An investigation was conducted into the relationships among the total number of aerosol particles and different types of airborne bacteria and their dependence on indoor and outdoor environmental factors, including air temperature and relative humidity (RH), in the indoor air of a dairy calf house in Tochigi, Japan, during the summer season. The concentrations of aerosol particles, the concentrations of airborne total aerobic bacteria (, , and spp.) in the indoor air, and the indoor and outdoor temperature and RH were evaluated from 14 weekly measurements. The mean concentration of small aerosol particles (0.3 to 2.0 µm) was higher than the mean concentration of large aerosol particles (2.0 to 10.0 µm) in the summer season. The mean concentration of airborne total aerobic bacteria was higher than the concentrations of airborne , , and spp. Airborne and were positively correlated with the number of 2.0 to 10.0 µm aerosol particles, i.e., high concentrations of 2.0 to 10.0 µm particles were correlated with high concentrations of airborne and . Airborne total aerobic bacteria did not correlate with the number of aerosol particles of any size, but spp. was negatively correlated with the number of 1.0 to 2.0 µm aerosol particles, i.e., high concentrations of 1.0 to 2.0 µm particles were correlated with low concentrations of airborne spp. The indoor temperature and indoor and outdoor RH did not correlate with any airborne bacteria. The outdoor temperature was negatively correlated with spp., i.e., high outdoor temperature was correlated with a low concentration of spp. in the indoor air of the dairy calf house. Both indoor and outdoor temperatures were positively correlated with the number of 0.5 to 5.0 µm aerosol particles, and indoor RH was negatively correlated with the number of 5.0 to 10.0 µm aerosol particles. These findings will be important for elucidating the role of aerosol particles in the transmission of airborne bacteria and ultimately for the mitigation of aerosol particles and airborne bacteria in dairy houses. HighlightsThe number of fine aerosol particles increased with increasing temperatures.Environmental factors had a less critical effect on airborne bacteria than aerosol particles.Airborne E. coli strongly positively correlated with 5.0 to 10.0 µm aerosol particles.Airborne Salmonella spp. negatively correlated with 1.0 to 2.0 µm aerosol particles.Relative humidity did not affect any airborne bacteria. Keywords: Aerosol particle number, Airborne bacteria, Dairy calf, Indoor air, Relationship, Summer season.

Characterization of the factors associated with the growth phase of dairy cattle in family farming

The aim of this study was to characterize the factors associated with the growth phase of dairy cattle used in family farming. We investigated 20 family-run milk production systems located in the Conceição de Ipanema municipality, MG, Brazil. Farmers were interviewed using a semi-structured survey form containing 152 questions. The questions were aimed at characterizing the farmer, herd, and husbandry system at pre- and post-weaning phases. Data were processed by using Sphinx® software, and descriptive analyses were performed in MS Excel® software. The results showed strengths, including navel healing (100%), location of the calf housing above (45%) or next to the pen (35%), and existence of a sanitary calendar (90%). However, several limitations in the management of calves and heifers were identified, such as lack of zootechnical bookkeeping (55%), manual milking with calf at the foot (65%), absence of herd sizing (100%), no routine weighing of calves (95%), incorrect colostrum management (80%), non-supply of transition milk to calves (85%), and likely failure to diagnose diseases by a fraction of the farmers. Thus, training regarding adequate management practices by extension technicians is imperative, along with the formulation of public policies that comply with the aspirations of family farmers, while promoting their economic and social sustainability.

A cross-sectional study of the welfare of calves raised in smallholder dairy farms in Meru, Kenya, 2017.

Aim:This study was aimed at describing calf comfort and determining the individual and pen level factors that affect comfort status (in particular, calf leg hygiene scores) of smallholder dairy farms in Meru County, Kenya.Materials and Methods:A cross-sectional study was carried out on 52 calves that were up to 1 year old in 38 dairy farms (mean±standard deviation: Herd size=1.71±0.7 milking cows and milk production=6.7±3.1 L/day) in Meru, Kenya, in 2017, with the intention to describe their comfort and determine the factors associated with leg hygiene as a critical parameter for calf comfort assessment. Calves’ biodata, health status, and leg hygiene were assessed, along with pen characteristics such as area, hygiene, and knee impact and knee wetness scores, while a questionnaire was administered to the farmers to gather information regarding calf housing management practices in the farm.Results:The calves had a mean body weight of 85.2±32.8 kg and average daily weight gain of 0.50±0.45 kg per day. 71% of calves had a good body condition score (≥2.5), and the mean space allowance per calf was 2.52±1.56 m2. Approximately 75% of the calves (39/52) were kept in pens, and the rest were reared outdoors. For 39 calves kept indoors, 26% (10/39) of them had wooden or concrete floors while 74% (29/39) had dirt floors. Nearly two-thirds (62%) of indoor calves (26/39) were reared in pens with bedding, and 23% (9/39) and 33% (13/39) of the calves reared indoors were kept in pens displaying a failed knee impact test and failed knee wetness test. Indoor housed calves had an increased probability of having dirty calf legs (cleanliness score of >2.5) by 8.6 times (p=0.031), compared to outdoor-housed calves. In the final multivariable logistic regression model of 39 calves in pens, concrete or wood floors (odds ratio [OR]=7.9, p=0.047), poor body condition (OR=17.1, p=0.020) and use of bedding (OR=12.5, p=0.046) appeared to be positively correlated with dirtiness of calf legs, compared to dirt floors, good body condition, and no bedding, respectively.Conclusion:Overall, some calf comfort aspects were covered for the majority of calves examined, but 69% of the pens were categorized as dirty, especially those with wooden or concrete floors and poor bedding management. Smallholder dairy farmers in Kenya should be trained on calf housing management to improve calf comfort and productivity.

Automatic cough detection for bovine respiratory disease in a calf house

In calf rearing, bovine respiratory disease (BRD) is a major animal health challenge. Farmers incur severe economic losses due to BRD. Additional to economic costs, outbreaks of BRD impair the welfare of the animal and extra expertise and labour are needed to treat and care for the infected animals. Coughing is recognised as a clinical manifestation of BRD. Therefore, the monitoring of coughing in a calf house has the potential to detect cases of respiratory infection before they become too severe, and thus to limit the impact of BRD on both the farmer and the animal. The objective of this study was to develop an algorithm for detection of coughing sounds in a calf house. Sounds were recorded in four adjacent compartments of one calf house over two time periods (82 and 96 days). There were approximately 21 and 14 calves in each compartment over the two time-periods, respectively. The algorithm was developed using 445 min of sound data. These data contained 664 different cough references, which were labelled by a human expert. It was found that, during the first time period in all 3 of the compartments and during the second period in 2 out of 4 compartments, the algorithm worked very well (precision higher than 80%), while in the 2 other cases the algorithm worked well but the precision was less (66.6% and 53.8%). A relation between the number of calves diagnosed with BRD and the detected coughs is shown.

Herd-level prevalence of the ultrasonographic lung lesions associated with bovine respiratory disease and related environmental risk factors

Bovine respiratory disease complex (BRD) is a major calf disease during the preweaning period. Thoracic ultrasound (TUS) has been recently described as a reliable tool for assessing BRD-associated lung lesions. The objectives of this study were to define the herd-level prevalence of lung consolidation assessed by TUS (CONSTUS). A total of 39 Québec dairy herds were randomly chosen to participate in this cross-sectional study. Between 6 and 12 preweaned calves were examined for signs of CONSTUS defined by any site with ≥3 cm consolidated lung tissue during 1 visit in summer and 1 visit in winter. Herd questionnaire focused on calf health and housing data [airborne bacteria (aerobic, coliform, yeasts and mold counts), air drafts, temperature, hygrometry, and ammonia levels] were also collected during these visits looking for potential association with CONSTUS prevalence. The median herd-level of CONSTUS prevalence (interquartile range) were 8% (0-22%) in summer and 15% (0-35%) in winter. Multivariable analyses showed that season was associated with an increased CONSTUS prevalence [10.0 vs. 19.3%; odds ratio (OR) = 2.16], as well as group housing during preweaned period (9.6 vs. 20.0%; OR = 2.37) and perceived BRD problem by the farmer (10.6 vs. 18.3%; OR = 1.89). Despite tremendous changes in calves' environment between winter and summer, none of the housing variables were associated with the CONSTUS prevalence in this study. Based on the observed CONSTUS prevalence ranges in the present study (herds in the lower prevalence quartile), an achievable goal of none of 12 calves with consolidation ≥3 cm can potentially be used to define a low-BRD risk herd.

Calves Use an Automated Brush and a Hanging Rope When Pair-Housed

Simple SummaryImproving calf housing is growing in interest as standard management meets only the basic needs of calves. In an observational study, we found that young calves interacted with an automated brush and a rope when given the opportunity. There was less variation in how much calves preferred the brush to the rope. Some calves used the rope as much as or more than the brush. We suggest that rope is a feasible, cheap, and farmer-friendly environmental enrichment option for housed calves; nonetheless, provision of multiple enrichment options should be considered to encourage use and meet individual calf preferences.Calf housing often only meets the basic needs of calves, but there is a growing interest in providing enrichments. This study described the behaviour of calves when they were given the opportunity to interact with two commonly available enrichment items. Female and male calves (approximately 11 days old) were pair-housed in 8 identical pens fitted with an automated brush and a hanging rope. Frequency and duration of behaviours were recorded on 3 separate days (from 12:00 until 08:00 the following day. Calves spent equal time using the brush and rope (27.1 min/day), but there was less variation in the use of the brush as opposed to the rope (coefficient of variation, CV: 23 vs. 78%, respectively). Calves had more frequent (94 bouts, CV: 24%) and shorter (17.8 s/bout, CV: 24%) brush use bouts compared to fewer (38 bouts, CV: 43%) and longer (38.3 s/bout, CV: 53%) rope use bouts. There was a diurnal pattern of use for both items. Frequency of play was similar to rope use, but total time playing was 8% of rope and brush use. Variability among calves suggested that individual preference existed; however, the social dynamics of the pair-housed environment were not measured and therefore could have influenced brush and rope use. Multiple enrichment items should be considered when designing improvements to calf housing.

0106 Evaluating preweaned calf housing and its impact on calf respiratory parameters on New York dairy farms

The objectives of this project were to (1) evaluate environmental and air quality parameters across different types of calf housing facilities; (2) evaluate rates of respiratory illness in preweaned calves; and (3) determine the impact of environmental factors, air quality, and housing type on calf health. This was an observational study in which calf facilities were evaluated on a single visit during June 2015. Housing included hutches (n = 9), individual pens in a barn (n = 11), and group pens in a barn (n = 9). Facility and calf pen evaluations included wind speed, temperature, relative humidity, heat stress index, bedding type, bedding composite sample for bacteria counts, nesting score of calf pens, calf health scoring, and airborne bacteria. Data were analyzed using SAS 9.3 to determine the impact of housing type, environmental, and air quality variables on calf respiratory score. A total of 29 facilities and 437 preweaned calves were evaluated. Calf facility temperature averaged 24.2°C (range 15.5 to 30.6°C) with a relative humidity of 21.5% (range 10 to 78%) and a heat index of 21.5°C (range 6 to 30.9°C). Temperature and airborne bacterial counts were greater in hutches as compared with individual and group pens (P < 0.01). Humidity was similar for hutches and group pens, but greater than individual pens. Gram negative airborne bacterial counts were lowest in individual pens. No difference in heat index was observed across housing type. Mean calf respiratory scores was 2.5 (range of 0 to 9) on a 12 point scale; 13.33% of calves evaluated scored greater than 5, indicating a respiratory challenge. Prevalence of respiratory illness in preweaned calves ranged from 0 to 50% of calves on a per farm basis (mean = 11.05% of calves/farm), with 44.82% of farms having no respiratory illness and 10.32% of farms having 30 to 50% of evaluated calves exhibiting signs of respiratory illness. There was a negative correlation between respiratory score and pen temperature (R2 = 0.90). There was no influence on respiratory score by housing system, bedding type, ventilation system, relative humidity, airflow, or airborne bacterial counts. Data collected from this study suggests that respiratory illness continues to be a challenge, even when weather is temperate. Additional research is needed to evaluate rates of respiratory illness during cold stress and transitional weather, as well as to evaluate management factors that increase the risk of infection.

Early recognition of bovine respiratory disease in calves using automated continuous monitoring of cough sounds

Bovine respiratory disease (BRD) complex in calves impairs health and welfare and causes severe economic losses for the Stockperson. Early recognition of BRD should lead to earlier veterinary (antibiotic/anti-inflammatory) treatment interventions thereby reducing the severity of the disease and associated costs. Coughing is one of the clinical manifestations of BRD. It is believed that by automatically and continuously monitoring the sounds within calf houses, and analysing the coughing frequency, early recognition of BRD in calves is possible. Therefore, the objective of the present study was to develop an automated calf cough monitor and examine its potential as an early warning system for BRD in artificially reared dairy calves. The coughing sounds of 62 calves were continuously recorded by a microphone over a three-month period. A sound analysis algorithm was developed to distinguish calf coughs from other sounds (e.g. mechanical sounds). During the sound recording period the health of the calves was assessed and scored periodically per week by a trained human observer. Calves presenting with BRD received antibiotic and/or anti-inflammatory treatment and the dates of treatment were recorded. This treatment date reference served as a comparison for the investigation of whether an increase in coughing frequency could be related to calves developing BRD. The calf cough detection algorithm achieved 50.3% sensitivity, 99.2% specificity and 87.5% precision. Four out of five periods, where coughing frequency was observed to be increased, coincided with the development of BRD in more than one calf. This period of increased coughing frequency was always observed before the calves were treated. Therefore, the calf cough monitor has the potential to identify early onset of BRD in calves.

Multilocus Sequence Typing and Antimicrobial Resistance of Campylobacter jejuni Isolated from Dairy Calves in Austria

Human campylobacteriosis is primarily associated with poultry but also cattle. In this study, 55 Campylobacter jejuni strains isolated from 382 dairy calves’ feces were differentiated by multilocus sequence typing and tested for antimicrobial resistance. The most prevalent sequence type (ST) was ST883 (20.0%), followed by ST48 (14.5%), and ST50 (9.1%). In contrast to ST48 and ST50, ST883 has rarely been described in cattle previously. Furthermore, risk factor analysis was performed for the presence of the most prevalent STs in these calves. Multiple regression analysis revealed that the type of farm (organic vs. conventional) and calf housing (place, and individual vs. group) were identified as significantly (p < 0.05) associated with the presence of ST883 in calves, and ST50 was associated with calf diarrhea. Antimicrobial resistance was detected in 58.2% of the isolates. Most of the resistant isolates (81.3%) were resistant to more than one antimicrobial. Most frequently, resistance to ciprofloxacin (49.1%), followed by nalidixic acid (42.8%), and tetracycline (14.5%) was observed. The results of the present study support the hypothesis that dairy calves may serve as a potential reservoir for C. jejuni and pose a risk for transmission, including antimicrobial resistant isolates to the environment and to humans.

Short communication: Field study of air ammonia concentrations in Ontario dairy calf housing microenvironments

Kaufman, J., Linington, M., Osborne, V. R., Wagner-Riddle, C. and Wright, T. C. 2015. Short Communication: Field study of air ammonia concentrations in Ontario dairy calf housing microenvironments. Can. J. Anim. Sci. 95: 539–542. The objective of this study was to measure the ammonia concentrations in the microenvironment of the calf housing area on a sample of commercial dairies in Ontario under typical management conditions. Two approaches were used to measure ammonia concentrations: (1) weekly on four farms for a period of 8 wk and (2) one-time samples were taken from the calf areas on 15 other farms. The results indicated that ammonia levels are managed below the existing maximum threshold provided in the national dairy code of practice.