8.1. A-Index modifications and repeatability
A-Index scores are shown in detail in Tables 5 and 6. Based on high Cronbach’s alphas (A-Index for calves ≤ 2 months 0.78, all others >0.8), reliability of A-Indices and WFS for all age groups was good. Comparatively good performance of calves ≤2 months of age in welfare scorings explained distribution of difficulties quite near zero. Only two items (calving and cow-calf -relationship) had difficulties over 0.5. Those items were excluded due to poor correlation with the full score. Items evaluating group size and number of teats per calf were excluded due to negative correlation with the full score. After evaluation 21 items were included in the WFS for animals under 2 months of age (Table 6).
Welfare of calves between 2 and 6 months was on an intermediate level (Table 5). Items evaluating roughage quality and the human-animal relationship were excluded due to negative correlation with full score. After evaluation 17 items were included in the WFS for calves between 2-6 months of age (Table 6). Welfare of bulls and heifers was estimated to be poorest of all age groups (Table 5). An item evaluating group size was excluded due to negative correlation with full score. After evaluation 18 items were included in the final score (Table 6).
Delivery and slaughter data of every delivered calf were connected to a particular WFS and A-Index score by the farm the calf had been in at a certain age to be used in epidemiologic models. The WFSs for different age groups were used as general welfare indicators, whereas A-Index scores were regarded as more production oriented measures. A-Index and WFS were available for 6 165 individual animals during all three age periods. Those animals were delivered for the first time to 75 different farms and slaughtered on 104 different farms.
Table 5. Description of joined A-Index data used in epidemiologic studies. The original articles describing particular indices are referred to by numbers I and II.
Variable Level of
observation Number of
observations Median Minimum Maximum Number of animals A-index for suckling
calves (≤2 months) (II) The farm rearing
calves on milk 90 79 47.5 92 12 942
WFS for suckling calves
(≤2 months) (II) The farm rearing
calves on milk 90 48 16 51 12 942
A-index for fattening calves (>2 to 6 months) (II)
The farm rearing
fattening calves 78 67.5 46.5 89.5 10 025
WFS for fattening calves
(>2 to 6 months) (II) The farm rearing
fattening calves 78 35 17 49 10 025
A-index for bulls and heifers (>6 to 24 months) (I,II)
Finishing farm 168 62 42.5 89.5 13 738
WFS for bulls and heifers
(>6 to 24 months) (I,II) Finishing farm 168 24 13 50 13 738
WFS = Welfare score, a subset of A-Index
Table 6. Items included in the welfare scores for each age group. Original articles are referred by numbers I and II.
Age group 0-2 months (II) >2 to 6 months (II) >6 to 24 months (I,II) Item name Mean score Max. score Mean score Max. score Mean score Max. score Length of the shortest
side of the pen 1.50 2 1.33 2 0.87 2
Confrontations
between animals 1.65 2 1.57 2 1.58 3
Space allowance 1.58 3 1.50 3 1.19 3
Possibilities to lie down and stand up in a natural manner
2.62 3 2.31 3 2.11 3
Tight floor on the
walking area 1.58 2 NI NI 1.18 2
Pen fixtures 0.84 1 NI NI NI NI
Group stability NI NI 0.50 4 NI NI
Group size NI NI 2.87 3 NI NI
Outdoor access in winter NI NI NI NI 0.11 2
Pasture access in
summer NI NI NI NI 0.21 2
Outdoor walking ground NI NI NI NI 0.25 2
Relations between calves 2.87 3 NI NI NI NI
Soft lying area 1.38 2 NI NI 1.45 6
Clean lying area 3.57 4 4.14 6 4.11 6
Tight lying area 1.82 2 1.48 2 1.37 2
Dry lying area 3.70 4 NI NI 1.45 2
Barn ventilation 3.11 4 2.87 4 2.93 4
Effective
temperature 3.28 4 1.35 2 NI NI
Draughts on lying area 3.41 4 2.58 4 2.43 4
Water availability 1.37 2 2.52 4 2.53 4
Noise NI NI 1.04 2 0.98 2
Night light 0.95 1 NI NI NI NI
Availability of
concen-trates 3.42 4 3.98 6 NI NI
Clean calves 2.75 3 2.40 3 NI NI
Traumas due to pen
fixtures 0.99 1 NI NI NI NI
Foot health NI NI NI NI 1.45 2
Loading facilities NI NI NI NI 0.85 1
Max. = maximum, NI= not included in the WFS of the particular age group
8.2. Factors affecting beef cattle performance: criterion validity and sensitivity of A-Index Welfare score affected mortality, fat and conformation score at slaughter (Figure 7, III-IV). Daily carcass gain was affected by the more production oriented A-Index (II). Other factors affecting the outcomes are described in Tables 7 and 8 (II-IV).
Figure 7. Predicted association between welfare score and production results on an average 200 bull farm.
Proportion of Conformation
Table 7. Description of models for estimated daily carcass gain and mortality.
Model Estimated daily
Observations 12 661 12 466 168
ICC 0.38 0.35 N/A
Constant 479 430 N/A
A-Index g/d per one unit 1.2 N/A N/A
WF-scale N/A NS Odds ratio 1.13 per each scale
unit for not any deaths Estimated class variables:
Number of delivered calves S NS S
Calf type S S NS
ZINB = zero inflated negative binomial model, N/A= not applicable, NS = non significant, S = significant effect.
Table 8. Description of models for fat scores 3-5, fat scores 4-5 and conformation scores O–E, N/A= not applicable, NS = non significant, p>0.1, p-values greater than 0.01 shown in the table.
Outcome Fat scores 3-5 Fat scores 4-5 Conformation score O-E
Number of observations 5288 5288 5120
Number of groups 78 78 80
ICC 0.13 0.16 0.17
Odds ratios (and their 95% confidence interval) for independent variables The WFS for bulls 6-24 months of age 0.55 (0.43–0.70)*** 0.55 (0.39–0.78)** 0.91 (0.84–0.98)*
Carcass weight, kg 0.98 (0.95–1.00) 1.02 (1.016–1.022)*** 1.02 (1.01–1.02)***
Average daily carcass gain at finishing,
kg/d a 1.0*10-18 (6.02*10-26-
1.66*10-11)*** 0.001
(2.97*10-9 - 342) 5.91*105
(4.35*104-8.03*106)***
Interaction between carcass weight and
average daily carcass gain at finishing 1.09
(1.05–1.14)*** NS NS
Sire inheriting low fat 16.0 (5.27–194)* 0.16 (0.064–0.39)*** N/A
Sire inheriting good conformation N/A N/A 2.60 (1.83–3.70)***
Interaction between sire and carcass weight 0.99 (0.98–1.00)** NS NS
Growth at calf rearing, kg/d 1.57 (0.98–2.51) NS NS
Interaction between the WFS and carcass
weight 0.9997 (0.9994–
Free roughage availability 1.47 (1.15–1.88)** 1.85 (1.22–2.79)** NS
Optimal roughage quality 0.73 (0.58–0.92) NS NS
TMR feeding 1.66 (1.31–2.10)*** NS NS
>320 delivered calves per year 2.58 (2.05–3.23)*** 1.95 (1.45–2.64)*** NS
* p<0.05, ** p<0.01, ***p<0.001, WFS = Welfare score, a subset of A-Index, TMR = Total mixed ratio
Responsiveness (criterion validity) of the A-Index and the WFS were estimated to be reasonable because estimated daily carcass gain and proportion of high conformation scores increased, and the proportion of high fat scores as well as mortality decreased in association with an increasing WFS, although the comparison criteria used did not include all aspects of welfare like fear, pain or frustration. A-Index and WFS were found to be sensitive welfare indicators reflecting small changes in outcome variables. A single unit corresponded approximately to a 1 g difference in daily carcass gain and 1% difference in proportion of fat scores.
8.3. Economic simulations
Cold housing with enhanced welfare and bedding based on own straw at a reasonable price was economically favourable. Net return to labour and management (NRLM) was €11 460, net profit
€8 720 and calculated salary €4.31/h greater in CH compared with WH (Table 9). Based on the smaller difference between median and minimum estimates, production risk was also slightly smaller in CH. These benefits were nearly lost using commercial average priced peat bedding (€75 /bull). In the case of expensive bedding (€150/bull), like purchased wood chips, NRLM was
€13 320 smaller in CH compared with WH (IV).
Table 9. Simulated economic results of a 200 bull farm in warm and cold housing in Finland.
Warm housing Cold housing
Net return for labour and management (NRLM), (T€) 29.7 41.0
Net profit (T€) 4.7 13.4
Calculated salary (€/h) 17.2 21.5
The effect of 27% increase (€0.19 vs €0.15/11,9 MJ) in feed price on NRLM, (T€) -21.84 -22.52
The effect of 20% change in calf price on NRLM, (T€) -17.04 -15.84
The effect of low target daily gain (500 g/d vs. 600g/d) on NRLM, (T€) -17.78 -12.39 The effect of 200% (€75 vs. €25/ bull place) increase in bedding price on
NRLM, (T€)
N/A - 9.88
T€= thousand euro, N/A= not applicable
In CH there was €0.02/kg more support compared with WH, but subsidy per NRLM was 190%
in CH compared with 223% in WH. Support per kilogram and meat production per delivered calf were quite stable in different scenarios, although CH favoured slightly (9kg) meat production per delivered calf (IV).
Restricted space allowance and increased number of animals were calculated to favour economic performance, although effects on production parameters were negative due to lower AW. An investment in rubber covered slats for the resting area was demonstrated to be profitable (IV).