TECHNICAL ARTICLES Dairy

Rearing of Holstein bull calves for meat production: Part I: veal production

Introduction

Dairy farmers in South Africa have been feeling the squeeze of escalating input costs on the one hand, and a stagnant (or decreasing) milk price on the other. Hence, dairy farmers are looking at ways to create new income streams for their enterprises. One option is to rear their male calves for meat production, either as veal or beef. The South African classification of a veal carcass calls for a dressed carcass weighing less than 100 kg. Beef carcasses obviously weigh more than 100 kg when dressed, and the target carcass weight is generally in the region of 200 kg and more. Hence, veal calf production can yield an income in a much shorter period (approximately 5 months of age) than beef production (approximately 12 months of age). However, veal meat is not as generally consumed as beef, and strictly speaking represents a niche market. Niche market products thus have a limited marketing scope, and should command a premium price. Such a premium price is not necessarily paid at all markets, and prospective veal producers should therefore target a specific market segment that will ensure a premium price, before venturing into this production system. The current study was undertaken to evaluate the biological and economic potential of Holstein bull calves fed two commercial calf diets from after weaning to approximately five months of age (veal production), under the assumptions of contemporary prices for feeds and weaner calves.

Materials and Methods

Day old Holstein bull calves were collected from dairy farms in the vicinity of Bloemfontein in the Free State Province (n=15), and the vicinity of Delmas in Mpumalanga Province (n=15). The calves were transported to Paradys Experimental Farm, University of the Free State, Bloemfontein. Calves were allocated to three different suckling phase treatments on a random basis from within the two provincial cohorts. Calves were reared with an acidified milk replacer formula (Surromel, 125 g per litre; 4 litres per calf per day), and different milk supply systems (bucket vs automated feeder – DeLaval CF150) and the same calf starter feed (Meadow Complete Calf 18 Pellets), or the same milk supply system (buckets) but different calf starter feeds (Meadow Complete Calf 18 Pellets vs Meadow Hipro 20 Calf Starter Meal). Calves were weaned after six weeks of liquid feeding. Statistical analysis of results revealed no significant performance differences between treatments (Van der Merwe et al., 2006). Hence, the 22 calves that were weaned, were randomly allocated to one of two post-weaning treatments (Meadow Complete Calf 16 Pellets vs Meadow Complete Calf 18 Pellets) such that each pre-weaning treatment was represented in approximately equal numbers in each post-weaning treatment. The 11 calves in each post-weaning treatment was then randomly divided into three replicate sub-groups (two groups of four calves, and one group of three calves). The calves in a replicate group were fed together in partly-roofed pens with concrete floors (floor space of approximately 32 m 2 and 4 m lateral feed bunk space, or 1 – 1.3 m lateral bunk space per calf). Water bunk space varied from 375 mm per calf (four-calf replicate groups) to 500 mm (three-calf replicate groups).

Calves received the appropriate commercial feed as their sole feed during the veal production experiment. Feed was supplied ad lib, twice a day (morning and afternoon feeding) from the word go, as it was assumed that the calves were adapted to high energy feed consumption during the pre-weaning phase. Feed intake was determined as the difference between air dry feed supplied and air dry feed refused. Refusals were collected once a day (before the morning feeding) and composited for weighing once a week. The crude protein and estimated energy content of the experimental feeds were 16% and 10.3 MJ ME Ruminant/kg (Complete Calf 16 Pellets) and 18% and 10.3 MJ ME Ruminant/kg (Complete Calf 18 Pellets), on as fed basis.

In the intervening period of one to two weeks between the end of the pre-weaning period, and the start of the post weaning period, the calves all received Meadow Complete Calf 18 Pellets on an ad lib basis. Calves were weighed at the start of the feeding period (when the Mapumalanga cohort were seven weeks old, and the Free State cohort was eight weeks old). Thereafter, calves were weighed with weekly intervals. Final weight was calculated by averaging the weight determinations over three consecutive days (day 91, -92, and -93) at the end of the 93-day feeding period.

Five calves, representing at least one calf randomly chosen from each replicate group, and a further two calves randomly chosen irrespective of replicate grouping, were selected from each treatment for slaughter at the Bloemfontein Abattoir. Carcasses were weighed warm, and again 24 hours later, to determine cold carcass weight, and percentage carcass shrink. Initial carcass weight was calculated by applying an assumed dressing percentage of 40% to the starting weight, and this weight was considered a cold carcass weight. Carcass weight gain was calculated as the difference between slaughter weight and initial carcass weight.

For statistical analysis of growth and carcass traits, the individual animal was considered to be the replicate unit. Feed intake and gross feed conversion ratio (FCR)(kg air dry feed consumed/kg body weight gain) were statistically analysed with the replicate group of calves as the experimental unit. The nett FCR (kg air dry feed consumed/kg cold carcass gain) was calculated by applying the gross FCR of the appropriate replicate group to individual calves in the slaughter groups, and was analysed with the individual calf as replicate unit. Feed, growth and carcass data were analysed by two-sample t-tests (Minitab, 2004), to compare the effect of feed type (Complete Calf 16 vs Complete Calf 18).

Statistical analyses of economic traits were confined to the calves from the slaughter groups, with individuals as replicates. To facilitate economic analysis, contemporary prices (March 2007) were assumed for feeds and weaner calves. The selling price of veal meat was varied from R 10/kg to R 15/kg to R 20/kg, to illustrate the importance of obtaining a premium price for veal carcasses in the economics of veal production. Feeding cost and initial value of weaners were analysed by two-sample t-tests as described above. The effect of carcass selling price on margin over feed cost was analysed by a paired t-test (minitab, 2004), on the pooled data of both feed types.

Results

The growth and feed intake results of all calves are summarized in Table 1, while growth, feed intake and carcass traits of slaughtered calves only are summarized in Table 2. Cost traits (slaughtered calves only) are summarized in Table 3, while the effect of carcass price variation on veal production economics is illustrated in Table 4 (for slaughtered calves only).

Wt = Weight ; DoF = Degrees of Freedom; ADG = Average Daily Gain;
ADFI = Average Daily Feed Intake; FCR = Feed Conversion Ratio

Wt = Weight ; DoF = Degrees of Freedom; ADG = Average Daily Gain;
ADFI = Average Daily Feed Intake; FCR = Feed Conversion Ratio;
CWt = Carcass Weight

CC 16 = R 2060/ton, CC 18 = R 2055/t (at Meadow Welkom ill gate in 50 kg bags, excluding VAT); Weaner price = R 12/kg liveweight

TABLE 4

Discussion

It is clear from the results in Table 1 that growth, feed intake, and gross FCR of Holstein bull calves raised for veal production from seven to eight weeks of age, and fed two different commercial calf diets, were not significantly affected (P>0.05) by the protein content (16% vs 18%) of the diet. Differences were minor for all traits considered. The growth rates achieved (1.24kg vs 1.32kg) demonstrate that Holstein weaner calves posses considerable growth capacity, accompanied by highly efficient conversion of feed to body weight. Variance, as measured by standard error of the means, were of a relatively low order, and quite similar between treatments. These results were recorded for all 11 calves per treatment.

The same pattern of growth, feed intake, and gross FCR emerges when only the slaughtered calves (n = 5 / treatment) are considered (Table 2). This gives one confidence that the slaughtered calves are representative of the entire treatment groups. Hence, the carcass traits of the slaughtered calves are in all probability a good reflection of these traits in all calves that received the treatments. Carcass traits were not significantly affected (P>0.05) by the feed treatments (16% vs 18% crude protein in the feed), and variance estimates were small in all cases.

The numerically higher starting weight of calves fed the 18% crude protein diet caused a fairly big difference in the starting value compared to the calves fed the 16% crude protein diet (R 85/calf; Table 3). Nevertheless, this difference was not statistically significant (P>0.05). Feed cost was numerically higher for the 18% crude protein diet than for the 16% crude protein diet (R 55/calf; P>0.05), and this was a reflection of the numerical difference in body weight, as calves in both treatments consumed feed at an average of 2.6% of their average body weight during the trial period. Because margin over feed cost merely reflects the nett effect of differences in the initial value and feed cost of the calves, it was expected that this financial indicator would not differ significantly between treatments, at all three carcass prices tested (r 10/kg, R 15/kg, and R 20/kg; results not shown). It is clear that only the highest carcass price (R 20/kg) resulted in profit, underscoring the point made in the introduction that veal calf production should be ventured into with caution, and only after a premium carcass price have been pre-determined. The results in Table 4 clearly illuminate carcass price as the major factor that influence profitability in veal calf production. Margin over feed cost was significantly improved (P<0.05) with every incremental hike in carcass price, when calves were fed diets capable of sustaining high levels of performance. Carcass prices of respectively R 16.58/kg (16% crude protein diet) and R 16.74/kg (18% crude protein diet) would be required to break even on margin over feed cost, under the economic assumptions pertinent to this trial. Clearly, higher carcass prices than the aforementioned will be required to cover overhead cost and remuneration of the entrepreneur, which will differ from enterprise to enterprise. Feed cost alone is generally considered to contribute about 80% of the total cost in intensive feeding systems, such as veal production.

Conclusions

It appears that 16% crude protein in the diet is adequate for weaned Holstein bull calves reared for veal production (carcass weight below 100 kg), from weaning time (six to eight weeks old) to approximately five months old (180 to 200 kg body weight). This level of crude protein in the diet sustained a high growth rate (over 1.2kg) and excellent gross FCR (below 2.8:1) in all treated calves. The slaughtered calves reflected almost identical results, giving confidence that these calves were representative of the larger treatment group. Cost of buying weaners and feed cost did not have a significant influence on margins over feed cost in veal production, but carcass price had a very strong and significant influence on returns. A carcass price of just under R 17/kg is necessary to break even on margin over feed cost of veal calves receiving a 16% crude protein diet, given prevalent weaner calf and feed prices . If a premium-paying niche market segment can be identified and secured up front, veal calf production from Holstein bull calves can be a profitable proposition.

Acknowlegement

The are grateful to Willem Pretorius for his help with day-to-day management of the trial animals.

References

Minitab, 2004. Minitab Release 14 for Windows, Statistical Software. Pugh Computers Limited, Llanon, Aberystwyth, Ceredigion, SY23 5LP, Wales, UK.

Van der Merwe, H.J., Slippers, S.C., Nieuwoudt, M, Schwalbach, L. & Fair, M.D., 2006. Evaluation of dairy calf rearing systems and calf starter concentrates. Unpublished research report produced for Meadow Feeds, P.O. Box 6224, Weltevreden Park, 1715.

Date published: 2007-03-28

Author:
S.C. Slippers,
H.J. van der Merwe

Publication:
N/A