Health, behaviour and growth performance of Charolais and Limousin bulls fattened on different types of flooring.

Intensive fattening of late-maturing breeds on concrete or rubberized slatted floors is the prevalent beef production system in mainland Europe. The rationale behind this study is that specific beef breeds with different slaughter weights might have a diverse response to different flooring systems. The study aimed at assessing whether growth performance, health, behaviour and claw condition of two beef breeds, Charolais (CH) and Limousine (LIM), would be affected by their housing on concrete (CS) or rubber-covered (RCS) fully slatted floor. A total of 228 CH (116 on CS; 112 on RCS) and 115 LIM (57 on CS; 58 on RCS) were housed in four and two commercial farms, respectively, in groups of 9.0 ± 2.1 animals/pen with an average space allowance of 3.1 ± 0.2 m2. Draining gaps of CS and RCS pens were 16.9 ± 1.7% and 11.6 ± 1.2% of the total surface, respectively. Bulls of both breeds had similar initial body weight (429.4 ± 31.5 kg for CH; 369.6 ± 31.7 kg for LIM), and they were slaughtered when they reached suitable finishing. Charolais had a higher final body weight (BW) than LIM (750.8 ± 8.6 v. 613.7 ± 10.9 kg; P < 0.01), and bulls of both breeds on RCS had higher average daily gain than on CS (1.47 ± 0.02 v. 1.39 ± 0.02 kg/day; P < 0.05). The percentage of bulls early culled or treated for locomotor disorders were reduced by RCS only for LIM, while RCS tended to prevent the occurrence of bursitis for both breeds. During two 8-h behavioural observations, bulls on RCS performed more head butt/displacements and chases than on CS, and they reduced the frequency of abnormal lying down events. The use of RCS increased mounts' frequency only in LIM, while its reduced drainage capacity impaired only the cleanliness of CH. Postmortem hoof inspection showed longer claw dorsal wall and diagonal lengths, and sharper toe angles for CH on RCS than LIM on both floors. Results of this study point out that fully slatted floors, regardless of being rubberized or not, are not suitable for bulls finished at a final BW above 700 kg due to their detrimental effects on health and welfare. The use of RCS could be recommended as an alternative to CS only if bulls are slaughtered at a lower final BW (around 600 kg), like in the case of LIM breed.

Risk factors associated with beef cattle losses on intensive fattening farms in Austria, Germany and Italy.

The aim of this study was to investigate management and feeding practices associated with on-farm loss rate (mortality) on 63 beef cattle farms in Austria, Germany and Italy with housing systems other than fully slatted pens. Information on mortality and 56 categorised factors relating to the cleanliness of animal facilities, health and feeding management, animal-human interaction, cattle transport and origin were gathered during on-farm visits. Samples of total mixed rations (TMRs) were collected and analysed for chemical composition and particle size distribution. Twenty-eight categorised factors were removed from the initial 56 due to exclusion criteria (missing data≥20% and/or monolevel factors with≥80% answers in one category). Mortality was the response variable in the risk factor analysis and the remaining 10 continuous covariates from TMR analyses and 28 categorised factors were independent predictors. Mean (±standard deviation) mortality, representing the proportion of dead, euthanased and early culled animals over the total number of animals bought in or reared in the previous year, was 2.8±3.5%. Fourteen factors were significantly associated with mortality in the bivariable analyses; seven factors were not considered further in the multivariable analysis due to collinearity. None of the factors related to TMR were associated with mortality. Four categorical factors, referring to biosecurity measures and management, were retained in the final multivariable model, with country effect. Buying cattle from only one farm, no mixing of animals during transport, presence of a dedicated sick pen and keeping production records were associated with lower percentage mortality.

Factors associated with passive immunity transfer in dairy calves: combined effect of delivery time, amount and quality of the first colostrum meal.

Despite the well-known importance of an adequate colostral immunoglobulin (Ig) transfer to calf health and survival, failed transfer of passive immunity (FTPI) remains a widespread problem in dairy farming. The aim of this study was to investigate the management factors associated with FTPI in newborn calves, evaluating particularly the combined effect of delivery time, amount and quality of the first colostrum meal. The study was conducted from March to August 2014 on 21 Italian dairy farms. Farmers were asked as first to answer a farm-level questionnaire on calf management. Blood sampling was then performed on overall 244 calves (1 to 5 days of age) born from Holstein cows, and a sample of the first colostrum meal of each calf was collected. Individual information on calves and the respective colostrum management were recorded. Serum and colostrum Ig concentrations were assessed by electrophoresis. A mixed effects multivariable logistic regression model was used to investigate the association of the variables obtained from both the management questionnaire and the individual calf data with FTPI (calf serum Ig concentration 87.6 g/l) within 1.0 h from birth. Considerable improvements are still needed about colostrum management for newborn calves in dairy farms. The results of this study will help in developing farm-specific programs for reducing the occurrence of FTPI.

A survey of selected animal-based measures of dairy cattle welfare in the Eastern Alps: Toward context-based thresholds.

In the Alps, traditional dairy farms are small-scale operations where vertical transhumance from valley indoor housing systems to highland pasture-based systems is still practiced in summer. Vertical transhumance implies a substantial change of environment, available resources, and management practices from one season to another. In such systems, animal-based welfare measures need to be monitored throughout the year to capture the variation of welfare outcomes, based on which targeted welfare management plans can be implemented. Because the Welfare Quality assessment approach has been tailored to indoor housing and intensive farming systems, the European Food Safety Authority recently developed a welfare assessment protocol for small-scale dairy cattle farms adapted after the Welfare Quality framework. The aim of this study was to assess nonbehavioral animal-based measures as defined by this protocol at different time points for transhumant systems in the Alps. In total, 18 animal-based measures were assessed before, during, and after the mountain pasture period in a sample of 67 small-scale dairy cattle farms practicing vertical transhumance in neighboring provinces of Austria, Italy, and Slovenia. Significant differences between assessments were identified for dirtiness of legs and teats, hairless patches, lesions and swellings, claw condition, ocular discharge, and diarrhea whereas BCS, lameness/severe lameness, vulvar discharge, nasal discharge, and hampered respiration were unchanged between seasons. In addition, a benchmarking exercise was carried out to identify relative boundaries (worst quartile thresholds) for each animal-based measure and to contribute to the discussion about achievable welfare outcomes for the 2 husbandry conditions that characterize a transhumant system. Worst quartile thresholds indicated a high prevalence of dirtiness (>80%) when cows were kept indoors, high prevalence of hairless patches (65%) before pasture turnout, and high prevalence of very lean cows (>13%) throughout the assessments. On the other hand, the best quartile thresholds for most clinical conditions suggested that high welfare standards (zero prevalence) are widely achievable in mountain farms practicing vertical transhumance during all assessments. The thresholds identified through benchmarking should serve as the basis for an effective context-based welfare management strategy promoting continuous welfare improvement on-farm.

Effect of a ceiling fan ventilation system on finishing young bulls' health, behaviour and growth performance.

This research aimed at assessing the effects of a ceiling fan ventilation system on health, feeding, social behaviour and growth response of finishing young bulls fattened indoors during a mild summer season. A total of 69 Charolais young bulls were housed in six pens without any mechanical ventilation system (Control) and in six pens equipped with ceiling fans. The experimental period lasted 98 days from June until mid-September 2014. Four experimental days were considered in order to assess the effect of the ventilation system under two different microclimatic conditions: 2 alert days at monthly interval with temperature humidity index (THI) between 75 and 78, and 2 normal days with THI⩽74. Health and behaviour of the bulls were evaluated through 8-h observation sessions starting after morning feed delivery. The study was carried out during a rather cool summer with a climate average THI of 68.9 and 4 days with average THI>75. Despite these mild climate conditions, ceiling fans lowered litter moisture and acted as a preventive measure for bulls' dirtiness (odd ratio=47.9; 95% CI 19.6 to 117.4). The risk of abnormal breathing was increased for Control bulls (odd ratio=40.7; 95% CI 5.4 to 304.2). When exposed to alert THI conditions, respiration rate and panting scores increased and rumination duration dropped in Control bulls compared with bulls provided with a ceiling fan. During observations under alert THI, bulls spent less time eating, more time being inactive and consumed more water compared with normal THI conditions. Bulls' daily dry matter intake measured during the observation sessions decreased on alert compared with normal THI days (P<0.001) due to a drop of intake during the daylight hours. Ceiling fan treatment had no effect on bulls' growth performance or water consumption but these results most likely depended on the mild climate conditions. Ceiling fans proved to mitigate some of the negative effects of heat stress on bulls' behaviour (rumination, lying down and drinking water) and respiration rate, however. The lack of a significant improvement of bulls' growth response should not discourage beef farmers from using ceiling fans in indoor systems, considering the likely increase in frequency and intensity of heat waves in the planet's temperate areas induced by global warming.

Short communication: Reference limits for blood analytes in Holstein late-pregnant heifers and dry cows: Effects of parity, days relative to calving, and season.

Reference limits for metabolic profiles in Holstein late-pregnant heifers and dry cows were determined considering the effects of parity, days relative to calving, and season. Blood samples were collected from 104 pregnant heifers and 186 dry cows (68 primiparous and 118 pluriparous) from 60 to 10 d before the expected calving date in 31 dairy farms in northeastern Italy. Sampling was performed during summer (182 samples) and the following winter (108 samples). All the animals were judged as clinically healthy at a veterinary visit before sampling. Outliers were removed from data of each blood analyte, and variables that were not normally distributed were log transformed. A mixed model was used to test the fixed effects of parity (late-pregnant heifers, primiparous or pluriparous dry cows), class of days relative to calving (60-41 d, 40-21 d, 20-10 d), season (summer or winter), and the interactions between parity and class of days relative to calving and between parity and season, with farm as random effect. Single general reference limits and 95% confidence intervals were generated for analytes that did not vary according to fixed effects. Whenever a fixed effect included in the model significantly affected a given analyte, specific reference limits and 95% confidence intervals were generated for each of its levels. Albumin, urea, triglycerides, alanine aminotransferase, aspartate aminotransferase, creatinine kinase, conjugated bilirubin, calcium, phosphorus, magnesium, potassium, chloride, zinc, copper, and iron concentrations were not influenced by any of the fixed effects. Total protein, globulins, creatinine, glucose, alkaline phosphatase, gamma glutamyltransferase, lactate dehydrogenase, and sodium plasma concentrations were affected by parity. The class of days relative to calving had a significant effect on the concentrations of total protein, globulins, fatty acids, cholesterol, total bilirubin, and sodium. Season affected plasma concentrations of creatinine, glucose, fatty acids, lactate dehydrogenase, and sodium. Interactions between parity and class of days relative to calving and between parity and season did not significantly affect any of the blood analytes tested. The reference limits and the 95% confidence intervals for blood analytes determined in the study could help dairy practitioners to improve the accuracy of metabolic profile interpretation in Holstein late-pregnant cattle.

Synthetic rubber surface as an alternative to concrete to improve welfare and performance of finishing beef cattle reared on fully slatted flooring.

The aim of this study was to compare a fully slatted concrete floor (concrete slatted (CS)) with the same floor on which synthetic rubber slats were placed on the concrete slats (rubber slatted (RS)) as housing solution for finishing beef cattle. The present study involved five commercial beef cattle farms in which the floor of at least three pens was kept as fully slatted, and in an equal number of pens a rubber cover was placed on the floor, tightly matching the gap profile of the concrete slats to allow the drainage of manure. A total of 326 finishing beef bulls were used (153 on CS and 173 on RS), and regardless of the floor treatment animals were housed in groups of 6 to 12 bulls/pen with a space allowance of 3.1 ± 0.2 m2/bull. Bulls had similar initial live weights (422.3 kg on CS and 425.0 kg on RS), but bulls on RS were heavier at the end of the finishing period with a higher average daily gain than bulls kept on CS (1.53 v. 1.46 kg/day; P<0.05). The proportion of bulls treated for locomotor problems was lower in RS pens compared with CS. Rubber covering prevented the occurrence of bursitis, but it increased the odds for hoof overgrowth at end of the finishing period. Hoof overgrowth detected in vivo in bulls on RS was confirmed at the slaughterhouse by the longer dorsal wall and diagonal lengths of the hoof as well as by a more acute toe angle. Compared with bulls on CS, bulls on RS showed less inactivity and resting time, increased social interactions, decreased abnormal lying down and unsuccessful attempts to lie down, as well as shortened the time for lying down. Bulls in RS pens were dirtier compared with those in CS pens, likely due to the draining gaps being reduced to 11.6 ± 1.2% of the total pen surface compared with the 16.9 ± 1.7% in CS pens. This study gave further evidence about the positive effects of the RS floor on growth performance and welfare of finishing beef cattle, although compromising cleanliness and hoof overgrowth.

Assessment of welfare of finishing beef cattle kept on different types of floor after short- or long-term housing.

This study aimed at evaluating short- and long-term effects of housing beef cattle on deep litter (DL) or concrete fully slatted floor (FS) on their welfare. Animal-based measures of the Welfare Quality® assessment protocol for cattle were used to assess health status and behaviour of bulls. The assessment was carried out in a large commercial farm on 15 batches of bulls (4 DL and 11 FS) 1 month after their receiving day (short-term) and on 12 batches (three DL and nine FS) the week before slaughter (long-term). Signs of better comfort on deep litter in terms of shorter lying down durations (5.1 ± 0.5 v. 6.5 ± 0.4 s; P<0.05) and lower risk of hairless patches (odds ratio=0.09; 95% confidence interval=0.01 to 0.68; P<0.05) were already observed after 1 month. Heavy bulls after a long-term housing on FS showed a higher prevalence of bursitis, hairless patches and lesions/swellings than animals on DL. Bulls on fully slatted floor were at higher risk of early culling (odds ratio=6.44; 95% confidence interval=1.57 to 26.37; P<0.01), mainly due to musculoskeletal system pathologies/lameness. Deep litter proved to be a valid alternative to slatted floor, making animals more confident to interact with powerful movements such as mounting at the end of the finishing period. A negative aspect of the deep litter was the poor cleanliness of the bulls. Compared with the fully slatted floor, there were higher odds ratios for dirty bulls at both, the short- (odds ratio=25.09; 95% confidence interval=8.96 to 70.22; P<0.001) and the long-term housing (odds ratio=276.13; 95% confidence interval=98.21 to 776.38; P<0.001). In order to improve health and welfare of beef cattle finished at a heavy weight, deep litter systems are a promising alternative to fully slatted floors. However, proper management of deep litter is necessary to maintain satisfactory cleanliness of the bulls.

Can novel methods be useful for pain assessment of castrated piglets?

Given that surgical castration is a painful practice performed on millions of pigs every year, a need to identify novel reliable pain assessment tools exists in order to test anaesthetic and analgesic protocols that may reduce related pain. Two treatments were considered: handling (H) and surgical castration (C). Physiological (cortisol, lactate, glycaemia, rectal and eye temperature) and behavioural variables (latency to move after treatment and alterations in posture and walking) were analysed. Cortisol showed the greatest level in C piglets within 20 min after the surgical procedure and a positive correlation with glucose concentration. Eye temperature was higher in C piglets, and the same difference was detected for rectal temperature 3 h after castration. Behavioural parameters revealed that C piglets had longer latency to move and a higher percentage of them showed alterations in posture and walking. Results of this study showed that, in castrated piglets behavioural and physiological alterations occur mainly in the first 3 h from treatment. Latency to move, alterations in posture and walking, and eye temperature appear to give additional and useful information in piglet pain assessment. However, differently from the behavioural parameters considered, eye temperature involves several manipulations of the animals and a long process to acquire the data.

Prevalence and potential influencing factors of non-nutritive oral behaviors of veal calves on commercial farms.

Veal calves raised under intensive conditions may express non-nutritive oral behaviors. When expressed in an abnormal way, these behaviors can be a sign of mental suffering and reduced welfare due to a mismatch between environmental or management features and the animal's needs. The aims of this study were to estimate the prevalence of non-nutritive oral behaviors in a large sample of veal farms in Europe and to determine the potential influencing factors present at farm level. Data were collected on 157 commercial veal farms in the 3 main veal-producing countries in Europe (the Netherlands, France, and Italy). Observations of 3 non-nutritive oral behaviors (manipulating substrates, tongue rolling, and manipulating a penmate) were performed when calves were aged 14 wk, and the prevalence of these behaviors was calculated. Information on management practices and characteristics of the building and equipment were collected on all farms to assess potential influencing factors for each of the 3 behaviors. Odds ratios and 95% confidence intervals were calculated to evaluate the effect of each individual factor within a generalized linear model. The mean percentage of calves per farm performing manipulating substrates was 11.0 ± 0.46%, performing tongue rolling 2.8 ± 0 .18%, and manipulating a penmate 2.7 ± 0.09%, with a high range between farms. Allowing more space for calves than the legal minimum requirement of 1.8 m(2)/ calf and housing them in groups of >10 calves/pen reduced the incidences of manipulating substrates and tongue rolling. Incidence of manipulating substrates was lower for calves fed maize silage compared with calves fed cereal grain, pellets, or muesli. A higher risk of tongue rolling was found when baby-boxes (i.e., single housing during the first 5 to 8 wk) were not used. Risk of calves manipulating a penmate was higher for calves of milk- or meat-type breeds compared with dual-purpose breeds and for calves fed with 280 to 380 kg compared with those fed >380 kg of milk powder in total for the fattening period. The study allowed assessment of multiple factors across farms that showed variety in terms of conditions and level of non-nutritive oral behaviors. Identification of the factors influencing non-nutritive oral behavior is helpful to define potential actions that could be taken on farms to improve the welfare of calves and reduce the prevalence of these behaviors.

Effects of the provision of solid feeds enriched with protein or nonprotein nitrogen on veal calf growth, welfare, and slaughter performance.

The study compared the effects of enriching a basic solid feed mixture made of corn grain and straw with a protein source (extruded pea) or with urea on growth, health, behavior, and carcass quality of veal calves. Seventy-nine calves, divided according to their initial body weight (59.8 ± 6.9 kg) into 3 groups (5 pens of 5 or 6 animals per group), were allotted to 1 of 3 experimental feeding treatments: milk replacer plus an 85:15 (as-fed basis) mixture of corn grain and wheat straw (CGS); milk replacer plus a 72:15:13 mixture of corn grain, wheat straw, and extruded pea (CGS-EP); or milk replacer plus an 83.3:16:0.7 mixture of corn grain, wheat straw, and urea (CGS-U). All feeding treatments were targeted to provide 140 kg of dry matter (DM)/calf of solid feed during the 201-d fattening cycle, and the greater crude protein content of the mixtures supplemented with protein or urea was balanced by restricting to 96% the daily amount of milk replacer delivered to CGS. Results did not differ among feeding treatments for average daily gain or solid feed intake but, net of meal refusal events, the average daily intake of milk replacer was 1.73, 1.66, and 1.60 kg of DM/calf for CGS, CGS-EP, and CGS-U, respectively. The overall mean hemoglobin values from samples taken at d 11, 40, 83, 126, and 196 were lower for CGS-U calves (9.1 ± 0.2 g/dL) compared with CGS (9.8 ± 0.2 g/dL), whereas those of CGS-EP were intermediate (9.4 ± 0.2 g/dL). Behavioral observations showed a frequency of oral stereotypes <1.2% for all feeding treatments. Longer eating and chewing or ruminating time was recorded for CGS-U calves compared with CGS and CGS-EP calves. All carcasses had satisfactory color for the veal market and none of the carcass traits were affected by the feeding treatments. The proportions of tongues and lungs with signs of lesions, forestomach development, abomasal lesions, and rumen plaques did not differ among feeding treatments. Hyperkeratinization of rumen papillae was observed only in CGS-U calves with a prevalence of 11.3%. Based on these findings, providing a corn grain and straw solid feed mixture enriched with extruded pea or urea was an effective strategy to reduce milk replacer consumption, lowering total feeding cost per calf by 3.0 to 3.4% and 6.9 to 7.2%, respectively. This economic advantage was supported by the lack of detrimental effects on calf growth performance, behavior, and carcass quality. However, the occurrence of rumen papillae hyperkeratosis may raise some concerns about the use of urea.

Alternative solutions to the concrete fully-slatted floor for the housing of finishing beef cattle: effects on growth performance, health of the locomotor system and behaviour.

The aim of this study was to assess the effect of two potential alternative solutions to the concrete fully-slatted floor (FS), namely, a perforated floor (PF) and a perforated floor coated with a rubber mattress (RM), on growth, locomotor system health, and behaviour of intensively finished young bulls. Forty-eight male beef-crosses (Charolais × Aubrac) were allotted to six pens of eight animals (two pens/floor type) for a finishing period of 175 ± 7 days. Growth was recorded and two health checks and two 8-h behavioural observations were carried out by trained assessors 1 month after the beginning of the trial (Initial) and 2 weeks before slaughter (Final). Feed intake was not affected by floor type, but average daily gain of RM bulls was higher than that of FS (1.37 vs. 1.19 kg, P=0.01), with PF being intermediate (1.27 kg). Behavioural observations showed that FS bulls had a higher number of slipping events (6.5) than PF (2.1; P=0.01) and RM bulls (0.9; P<0.01). Bulls on FS showed more lying down attempts (2.2 vs. 0.1; P=0.001), a lower number of lying/standing transitions (4.5 vs. 7.3; P<0.001) and a longer lying duration (5.9 vs. 4.7s; P<0.01) than RM bulls. Signs of lameness were observed in five FS bulls at the final assessment. RM floor proved to be a good alternative to FS but it increased the likelihood of overgrown claws due to insufficient hoof wear.

Evaluation of on-farm veal calves' responses to unfamiliar humans and potential influencing factors.

The human-animal relationship is an important component of the welfare of farm animals and for this reason animal responsiveness tests to humans are included in on-farm welfare assessment schemes that provide indicators for this. However, apart from the behaviour of stockpersons towards their animals, other factors may also influence animals' reactivity to humans as observed through behavioural tests, which can add a further layer of complexity to the interpretation of test results. Knowledge of these factors may help a better interpretation of differences from one farm to another in the outcome of human-animal relationship tests, and may provide clues for improving the relationship between animals and humans. The main objective of this study was to identify whether management or environmental factors could influence the outcome of human-animal relationship tests in veal calves. Two tests were performed when calves were aged 14.9 ± 1.6 (SD) weeks in 148 veal farms: the voluntary approach of an unfamiliar human standing at the feeding fence and the reaction towards an unfamiliar human who entered the home pen and tried to touch each calf in a standardised way (Calf Escape Test (CET) - score 0 to 4). Questionnaires were filled in and interviews with the stockpersons were performed in order to obtain information on stockpersons, management, animal and building characteristics. The latency to touch an unfamiliar human at the feeding fence was significantly correlated with the CET scores. Total number of calves on the farm, space allowance, breed, environmental enrichment, stockperson's experience and season of observation influenced the percentage of calves that scored 0 in CET (i.e. calves that could not be approached). Type of milk distribution, type of breed and number of calves per stockperson influenced the percentage of calves that scored 4 in CET (i.e. calves could be touched). For both CET0 and CET4, the level of self-reported contacts by the stockperson (analysed only on the French subset of 36 farms) did not influence the results. This paper concludes that according to the tests conducted on veal calves on commercial farms, factors such as milk distribution method, breed of the calves or the level of experience of stockpersons with veal farming can have an impact on the results of tests focusing on human-animal relationships.

Effects of the provision of large amounts of solid feeds to veal calves on growth and slaughter performance and intravitam and postmortem welfare indicators.

Polish Friesian male calves (n = 78) were used to investigate the effects of innovative feeding plans based on the provision of large amounts of solid feeds on growth performance, welfare, and carcass characteristics of veal calves. Groups of calves (initial BW 71.5 ± 3.7 kg) were fed 1 of 3 treatments (26 calves/treatment): 1) milk replacer plus corn grain (CG), 2) milk replacer plus an 80:20 mixture (as-fed basis) of corn grain and wheat straw (CGS), or 3) milk replacer plus a 72:20:8 mixture (as-fed basis) of corn grain, wheat straw, and extruded soybean, respectively (CGSES). All the treatments provided at least 170 kg DM/calf from solid feed throughout the 206 d of fattening. Type and concentration of milk replacer were the same for all calves throughout fattening. Calves fed CGSES received 96% of the daily amount of milk replacer delivered to CG and CGS to balance the dietary CP content. No differences (P ≥ 0.063) among treatments were observed for growth performance and DMI. Health status of CG calves was less than CGSES calves, as indicated by the greatest (P < 0.001) proportion of milk replacer refusal events and the greatest (P < 0.001) incidence of treatments for respiratory disorders. Inclusion of straw and soybean in the solid feeds increased (P < 0.001) the daily intake of iron in CGS and CGSES as compared with CG; however, blood hemoglobin concentrations measured at d 5 and 31 were greater (P < 0.05) than when measured on d 80, 122, and 206 of fattening. Feeding treatment did not (P ≥ 0.107) affect HCW, dressing percentage, or carcass color. Calves fed CG had heavier (P < 0.001) reticulorumens and more (P < 0.001) developed rumens than CGS and CGSES calves, but 84% and 68% of CG rumens (P < 0.001) showed overt signs of hyperkeratinization and plaques, respectively. These alterations of rumen mucosa were not detected in CGSES calves, and only 8% of CGS calves had rumen plaques. Regardless of feeding treatment, postmortem inspection recorded a prevalence of more than 84% abomasal lesions. When feeding veal calves with large amounts of solids, it is advisable to avoid the provision of corn grain alone and replace part of the cereal with a roughage source to improve calf health and prevent rumen mucosa alterations.

Prevalence of respiratory disorders in veal calves and potential risk factors.

The study aimed to assess the in vivo and postmortem prevalence of respiratory disorders in veal calves and investigate risk factors associated with them. A cross-sectional study was carried out in 174 farms in the 3 major veal meat-producing countries in Europe (50 in France, 100 in the Netherlands, and 24 in Italy). Trained veterinarians visually evaluated individual calves of 1 batch per farm at 3 and 13 wk after arrival and at 2 wk before slaughter to assess the prevalence of hampered respiration, nasal discharge, and coughing. A random sample of lungs belonging to calves of the same batch was monitored at the slaughterhouse for mild to moderate or severe signs of pneumonia, and presence of pleuritis. Data regarding veal calf housing, feeding, and management and specific characteristics of the batch were collected through an interview with the stockperson, and the potential of these as respiratory disease risk factors was assessed. Regardless of the stage of fattening, the prevalence of in vivo signs of respiratory disorders in calves was always <7%. This low prevalence was likely the outcome of the general implementation by veal producers of standardized practices such as prophylaxis, all-in/all-out, and individual daily checks of the calves, which are recognized tools for effective disease prevention and management. However, at postmortem inspection, 13.9% and 7.7% of lungs showed mild to moderate and severe signs of pneumonia, respectively, and 21.4% of the inspected lungs had pleuritis. Thus, even mild clinical signs of respiratory disorder in calves at specific time points during the fattening period may be associated with high prevalence of lungs with lesions at slaughter. Alternatively, clinical symptoms recorded during routine visual inspections of veal calves on-farm may be poor predictors of the true prevalence of respiratory disease in calves. Among all potential risk factors considered, those concerning the characteristics of the batch were predominant but factors related to housing, management and feeding equipment were also relevant. Different risk factors were involved at different stages of the fattening period. Therefore, to overcome respiratory disorders in veal calves, different solutions may apply to different stages of the fattening period.

The relationship between clinical signs of respiratory system disorders and lung lesions at slaughter in veal calves.

The presence and severity of lung lesions recorded post-mortem is commonly used as an indicator to assess the prevalence of respiratory problems in batches of bovines. In the context of a welfare monitoring based on on-farm measures, the recording of clinical signs on calves at the farm would be more convenient than the recording of lung lesions at slaughter. The aim of the present study was to investigate the relationship between clinical respiratory signs at farm and post-mortem analyses of lung lesions observed at slaughter in veal calves. If clinical signs were a good predictor of lung lesions it could be possible to integrate only those measures in a welfare monitoring system. One-hundred-and-seventy-four batches of calves were observed 3 times: at 3 and 13 weeks after arrival of the calves at the unit and at 2 weeks before slaughter. For each batch a maximum of 300 calves was observed and the proportions of calves showing abnormal breathing, nasal discharge and coughing were recorded. Post-mortem inspection was carried out on a sample of lungs belonging to calves from the observed batches. Each examined lung was classified according to a 4-point scale for pneumonia from healthy lung (score 0) to severe lesions (score 3). The clinical signs recorded infra vitam were significantly correlated with moderate and severe lung lesions for observations at 13 weeks and 2 weeks before slaughter and the level of the correlation was highly variable (r(sp) from 0.16 to 0.40). Receiver operating characteristic (ROC) curves were created and the area under the curves showed that batches with a high proportion of lungs with moderate or severe lesions could not be accurately detected by the three clinical signs of respiratory disorders. These results suggest that both clinical signs and post-mortem inspection of lung lesions must be included in a welfare monitoring schemes for veal calves.

Short communication: reference values for blood parameters in Holstein dairy cows: effects of parity, stage of lactation, and season of production.

Confidence intervals for blood parameters used for nutritional and metabolic profile testing in cattle were calculated for clinically normal lactating Holstein cows, taking into account the effects of parity, stage of lactation, and season. Blood samples were collected from 740 cows in 33 Italian dairy herds according to a predefined protocol. Herds were visited during summer and the following winter, sampling 12 lactating cows at each visit (4 primiparous and 8 multiparous). Six cows were selected from the early-lactation group (days in milk: 10 to 89) and the other 6 were selected from the mid-lactation group (days in milk: 90 to 215). Cow selection criteria excluded animals clinically exposed to periparturient diseases as well as animals not considered in good health by a veterinary clinical examination. For each blood variable, outliers were identified and discarded. Data were then analyzed for their Gaussian distribution and variables with not normal distribution were log-transformed to adjust for lack of normality. Herd mean values were calculated for each blood parameter according to 3 main classification factors: parity (primiparous vs. multiparous), stage of lactation (early vs. mid) and season of production (summer vs. winter). The resulting data set was statistically analyzed using a mixed model with the fixed effects of these factors, their interactions, and the random effect of herd. General 95% confidence intervals were calculated for blood variables that showed a relevant herd variance component such as albumin, triglycerides, aspartate, urea, glucose, alanine aminotransferase, lactate dehydrogenase, direct and total bilirubin, calcium, magnesium, and potassium. For the remaining parameters, specific confidence intervals were calculated for each level of the significant main factors. Parity affected blood concentration of total protein, globulin, creatinine, alkaline phosphatase, gamma glutamyl transferase, creatinine kinase, and phosphorus. Blood nonesterified fatty acids, aspartate aminotransferase, gamma glutamyl transferase, creatinine kinase and cholesterol were influenced by stage of lactation. The season of production had a significant effect on total protein, globulin, creatinine, alkaline phosphatase, phosphorus, sodium, and chlorine. The outcomes of this work will improve the accuracy of the biochemical profile as a tool for dairy practitioners to assess the metabolic status of lactating Holstein cows.

Prevalence of gastrointestinal disorders recorded at postmortem inspection in white veal calves and associated risk factors.

The study aimed at assessing the prevalence of poor rumen development, presence of rumen plaques, rumen papillae hyperkeratinization, and abomasal lesions in veal calves and to investigate risk factors for their occurrence at the farm level. Within a wide cross-sectional study, a sample of 170 veal farms representative of the European veal meat production systems was considered in the 3 major producing countries (99 in the Netherlands, 47 in France, and 24 in Italy). An average of 59 ± 10 (SD) rumens and abomasa belonging to calves from a single batch per farm were inspected at the abattoir by trained observers to assess the incidence of these gastrointestinal disorders. Potential risk factors for their occurrence related to farm management, housing, and to the feeding plan were obtained by a questionnaire submitted to the stockperson. Prevalence of poor rumen development (almost no papillae present), rumen plaques, and hyperkeratinization were 60.4, 31.4, and 6.1% of rumens, respectively, whereas abomasal lesions in the pyloric area were recorded in 74.1% of abomasa. Independent variables related to the feeding system confirmed to be the main risk factors for the occurrence of gastrointestinal disorders in veal calves. However, additional risk sources for each given problem were identified among housing and management variables. The provision of a low amount of solid feed (≤ 50kg of dry matter/head per cycle) was a relevant risk for rumen underdevelopment. Rumen wall alterations (plaques and hyperkeratinization) and abomasal lesions were instead associated with the administration of large quantities of solids (151-300 kg of dry matter/head per cycle) in calves receiving milk replacer during the entire fattening cycle. Among the types of solid feed, cereal grain acted as a preventive measure for low rumen development, whereas it was a risk factor for the occurrence of rumen plaques, papillae hyperkeratinization, and abomasal lesions. Some housing and management options adopted to improve veal calf welfare (i.e., higher space allowance and use of heating) were associated with lower risk for gastrointestinal disorders.

Administration of dexamethasone per os in finishing bulls. I. Effects on productive traits, meat quality and cattle behaviour as indicator of welfare.

The study investigated the effects of prolonged oral administration of dexamethasone at a low daily dosage of 0.75 mg/head per day (Dexa) on beef cattle productive traits, behaviour and meat quality. In all, 14 finishing Marchigiana bulls were used in a trial that begun 56 days prior to slaughter, of which six bulls received treatment from day 5 to day 53, whereas the remaining animals were used for Control. The animals treated showed an increased average daily gain (1515 v. 1177 g/head per day; P < 0.05; s.e.d. = 48.54) and improved warm carcass dressing percentage (60.8% v. 59.7%; P < 0.05; s.e.d. = 0.32). Behavioural observation did not permit a clear distinction between treated and Control animals since feeding and social behaviour were similar in both groups. The bulls treated spent less time lying (16.5% v. 34.6%; P < 0.05; s.e.d. = 4.38) and grooming (6.7% v. 11.9%; P < 0.05; s.e.d. = 1.23), and this may indicate poorer welfare. No evidence of treatment was observed in other carcass traits, and redness was the only meat quality parameter slightly affected by corticosteroid administration.

Administration of dexamethasone per os in finishing bulls. II. Effects on blood parameters used as indicators of animal welfare.

A set of hormonal, haematological and biochemical parameters was used to evaluate the physiological response and welfare status of 14 finishing Marchigiana bulls treated for 49 days with a low daily dosage (0.75 mg/head per day) of dexamethasone per os. Compared to the Control group, dexamethasone decreased cortisol concentrations (42.3 v. 5.7 nmol/l; s.e.d. = 4.17; P < 0.001), and led to the reversal of the leukocyte formula in the animals treated (P < 0.05). Total serum proteins (70.2 v. 73.9 g/l; s.e.d. = 1.55; P < 0.05), in particular ß1 globulins (7.5 v. 9.1 g/l; s.e.d. = 0.24; P < 0.01) and fibrinogen (199 v. 258 mg/dl; s.e.d. = 32.70; P < 0.05), increased as a consequence of treatment. Prolonged dexamethasone administration led the bulls to an apparently chronic stress condition. Moreover, the study indicated various blood parameters that might be used by health officials as effective tools in identifying beef cattle suspected of being illegally treated with dexamethasone.