The aim of the study was to compare different behavioural, physiological and performance traits in three groups of veal calves fed either a routine all-liquid diet with milk replacer (GO) or the same diet supplemented with a total of 10kg (G10) or 25kg (G25) of pelleted straw and cereals. Each of the three feeding programmes involved 21 male Friesian calves kept in individual crates for 20 weeks (from 1 to 21 weeks of age). Oral activities, haematological variables, ruminai characteristics, health and performance were all investigated. In calves supplied with dry feed, there was no evidence of ruminating behaviour; and chewing, regarded as a non-nutritive oral activity, was clearly reduced. The incidence of tongue playing and manipulating objects was not influenced by additional pellets.

Haemoglobin concentrations were higher in G25 than in other groups as a result of the extra iron supplied in the pellets. Other blood variables were unchanged. In G10 and G25 changes in rumen characteristics were clearly demonstrated by the following observations: i) the weight of reticulo-rumens increased by 11 and 35 per cent, respectively; ii) small papillae (virtually non-existent in calves fed an all-liquid diet) were present, and there was a darkening of the mucosa; and iii) there was a marked reduction in the number of hairballs, resulting from a continuous elimination of ingested hair by ruminai motility. In G25, carcase weight was significantly (P < 0.05) increased by 6.5 per cent compared with controls and no detrimental effects such as bloating or abomasal ulceration were observed when dry feed was added. Supplying calves with straw-cereal pellets was considered positive for the physiological aspects of welfare in veal calves. However, other diet compositions capable of inducing rumination behaviour should also be investigated.

The objective of this study was to investigate inter-observer and test-retest reliability of different behavioural observations to be used in an on-farm, animal welfare monitoring system for veal calves. Twenty-three veal calf farms, varying in size, housing system, feeding regime and age of the calves were visited twice with two observers, simultaneously. Behavioural tests were conducted in eight pens per farm, measuring the response of calves to: a human entering the barn; a novel object; a passive, unfamiliar person; disturbance in the pen and an active approach by an unfamiliar and a familiar person. Furthermore, behaviour was recorded 20 min before and 20 min after feeding in eight other pens per farm. For all behavioural tests, inter-observer reliability was very high. Farm effects and test-retest reliabilities were high and significant for all behavioural tests, except for the test measuring response to disturbance in the pen. Although the active approach test with the familiar person was reliable, it was not feasible in practice due to the availability of the farmer. Since the active approach test with the unfamiliar person gave similar results, this test was recommended for an on-farm animal welfare monitoring system. For most behavioural elements recorded around feeding, farms differed significantly and interobserver and test-retest reliabilities were high as well as being significant. The behavioural tests with entering the barn, novel object and unfamiliar person, and the behavioural observations before and after feeding were feasible and distinctive and reliable enough to be performed on-farm. These methods are promising tools to use as a monitor of animal welfare in veal calves.

This study aimed at assessing the effect of the observation method (direct or from video) and the effect of the presence of an observer on the behavioural results in veal calves kept on a commercial farm. To evaluate the effect of the observation method, 20 pens (four to five calves per pen) were observed by an observer for 60 min (two observation sessions of 30 min) and video-recorded at the same time. To evaluate the effect of the presence of the observer in front of the pen, 24 pens were video-recorded on 4 consecutive days and an observer was present in front of each pen for 60 min (two observation sessions of 30 min) on the third day. Behaviour was recorded using instantaneous scan sampling. For the study of the observer's effect, the analysis was limited to the posture, abnormal oral behaviour and manipulation of substrates. The two observation methods gave similar results for the time spent standing, but different results for all other behaviours. The presence of an observer did not affect the behaviour of calves at day level; however, their behaviour was affected when the observer was actually present in front of the pens. A higher percentage of calves were standing and were manipulating substrate in the presence of the observer, but there was no effect on abnormal oral behaviour. In conclusion, direct observations are a more suitable observation method than observations from video recordings for detailed behaviours in veal calves. The presence of an observer has a short-term effect on certain behaviours of calves that will have to be taken into consideration when monitoring these behaviours.

Metabolic body size of veal calves is still calculated by using the 0·75 exponent and no data were available to determine energy cost of physical activity during the whole fattening period. Data from two trials focusing on protein and/or energy requirements were used to determine the coefficient of metabolic body size and the energy cost of standing activity in male Prim'Holstein calves. Total heat production was measured by indirect calorimetry in ninety-five calves weighing 60–265 kg and was divided using a modelling approach between components related to the BMR, physical activity and feed intake. The calculation of the energy cost of standing activity was based on quantifying the physical activity by using force sensors on which the metabolism cage was placed and on the interruption of an IR beam allowing the determination of standing or lying position of the calf. The best exponent relating zero activity fasting heat production (FHP0) to metabolic body size was 0·85, which differed significantly from the traditionally used 0·75. Per additional kJ metabolizable energy (ME) intake, FHP0 increased by 0·28 kJ; at a conventional daily 650 kJ/kg body weight (BW)0·85 ME intake, daily FHP0 averaged 310 kJ/kg BW0·85. Calves stood up sixteen times per day; total duration of standing increased from 5·1 to 6·4 h per day as animals became older. The hourly energy cost of standing activity was proportional to BW0·65 and was estimated as 12·4 kJ/kg BW0·65. These estimates allow for a better estimation of the maintenance energy requirements in veal calves.

An experimental administration of dexamethasone was carried out on 15 veal calves in order to assess the rôle of low doses of exogenous glucocorticoids on productive traits and meat quality. Three groups, of five veal calves each, were formed: one group received oral dexamethasone (0·4 mg per calf per day for 25 days), another intramuscular (i. m.) dexamethasone (2 mg at days 14 and 21), and the third was the control. Calves were slaughtered at 165 days of age (day 31). Food conversion ratio (FCR), hot dressing percentage (HDP), chilled dressing percentage (CDP) and shrinkage were determined. From all carcasses, samples of m. longissimus thoracis (between the 8th and 10th rib) were taken in order to evaluate the chemical composition and some organoleptic characteristics: meat colour, waterholding capacity and tenderness. The animals treated with oral dexamethasone showed the lowest daily weight gain (P 0·05) and the poorest FCR (P 0·05). Hot dressing percentage, cold dressing percentage and shrinkage were not affected by the oral treatment. The i. m. injections of dexamethasone did not influence the overall performance. Muscle chemical composition and pH were not affected by the treatments; the meat of calves treated with oral dexamethasone was significantly lighter (P 0·05) and tended to be paler, while i. m. treatment induced intermediate characteristics. The shear force of the meat was rather low. Shear force of cooked meat from animals treated with dexamethasone (both oral and i. m.) was significantly lower than the control (P < 0·05). Treatment with dexamethasone i. m. induced a decrease in water-holding capacity; the oral treatment had no effect on this parameter.

Although veal production is a highly standardized system, there still remains considerable variability in productivity between units. This variability might be due to the farmers working on these units, through differences in stockmanship, work attitudes or behaviour, which in turn may affect animals’ fear responses, productivity and health. A survey was conducted on 50 commercial farms affiliated to the same veal company. All units had calves housed in individual crates, a similar number of crates, and the same diets and management advice. Data were collected on: building and general farm characteristics, farmers’ backgrounds and their attitudes towards their work and calves, farmers’ behaviour with the calves, calves’ reactivity to people, and disease level of the calves. Productivity results (growth rates, food efficiency and mortality) were used to classify veal units as ‘high producing’ (no. = 24) v. ‘moderate producing’ (no. = 26). Calves were less reactive to people in units where the farmer behaved sympathetically and where there were several stockpersons working. The disease level was lower in units where the farmer had a positive attitude towards the sensitivity of the calves to contact and towards the importance of cleaning. Productivity of the veal unit was associated with the health of the calves but not with their reactivity to people.

It is suggested that the farmer can have an influence on the success of the veal unit mainly through his/her ability to control the health of the calves and that a positive attitude towards animals and towards work (specifically cleaning actions) can improve the accuracy of surveillance and care of the animals. Moreover, through his/her behaviour with the calves and his/her ability to control their health, the farmer can play an important rôle in assuring calves’ welfare.