Effect of marketing strategy on the production performance of cattle herds from four different breed types in the arid sweet bushveld

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SA-ANIM SCI 2004, vol 5: http://www.sasas.co.za/popular/popular.html 1 Effect of marketig strategy o the prouctio performace of cattle hers from four ifferet bree types i the ari sweet bushvel I u Plessis 1, 2# & LC Hoffma 2 1 Limpopo Provice Departmet of Agriculture, Mara Research Statio, Private Bag X2467, Makhao (Louis Trichart) 0920, South Africa 2 Departmet of Aimal Sciece, Uiversity of Stellebosch, Private Bag X1, Matiela 7602 South Africa Abstract Various bree types a prouctios systems are use to prouce beef from atural pastures. I ari regios with erratic raifall patters, flexible prouctio systems will assist the sustaiable use of la. Cattle bree types (Simmetaler crossbre, Bosmara crossbre, Afrikaer a Ngui) ifferig i frame size were use to illustrate the effect of marketig strategy (weaers vs. 30 moth ol steers) o prouctio performace. The actual pregacy, weaig a growth rates etermie for the respective bree types were use to calculate prouctio performace. For all bree types marketig steers at 30 moths of age resulte i more kilograms live weight markete tha whe marketig weaer calves. Differeces i kilograms live weight prouce were also observe betwee the various bree types (Ngui > Bosmara crossbre > Simmetaler crossbre > Afrikaer). The reprouctio rate of the a the survival rates of the calves ha a more proouce ifluece o prouctio efficiecy tha the growth rate of the calves. The characteristics of the respective bree types must be take ito accout whe eciig o a bree type as well as the prouctio a marketig system to be followe. # Correspoig author. E-mail: iuplessis@latic.et Itrouctio Proucers use ifferet brees of cattle ifferig i frame size combie with ifferet prouctio a marketig strategies to prouce meat from atural pastures i ari regios. I ari regios the raifall is erratic a ureliable. Pressure o la-users to use la sustaiably, is icreasig. Ajustmets i various aspects of la use are ecessary to accomplish this. Usig bree types a prouctio systems that are aapte to a specific eviromet a the climatic coitios prevalet i that eviromet becomes icreasigly importat. The choice of the most suitable prouctio system shoul ot be base o what short-term beefits the oe hols over the other, but rather the log term beefits a sustaiability thereof. The aim of this stuy was to provie prouctio guielies for two marketig strategies (weaers or 30 moth ol steers) that ca be followe with various bree types of cattle a to highlight some of the beefits of the two marketig systems. Materials a Methos The stuy was coucte from 1995 to 2002 o ca. 4 387 ha o the easter sie of the Mara Research Statio (23 05 S a 29 25 E; 961 m.a.s.l). The Mara Research Statio is situate i the Ari Sweet Bushvel of the Limpopo Provice of South Africa (Acocks, 1988). The vegetatio i the stuy area iclues the wooy species Acacia tortilis, Commiphora pyracathoies, Boscia albitruca a Grewia spp. a the grass species Eragrostis rigiior, Paicum maximum, Urochloa mosambicesis a Digitaria eriatha (Dekker et al., 2001). The log term mea raifall is 452 mm of which approximately 80% occur from November to March. Durig the stuy perio, the mea aual raifall (measure from July to Jue) was 453 mm (Table 1). The mea aily maximum temperature rage from 22.6 C i Jue to 30.4 C i Jauary. I this ivestigatio the prouctivity of four ifferet brees/frame sizes o sweetvel was evaluate. Cows cosistig of approximately 2 / 3 Simmetaler were mate to Simmetaler bulls. They a their offsprig represete large frame bree types (SX). Cows (ca. 2 / 3 Afrikaer) were mate to Bosmara bulls. They a their offsprig represete meium frame bree types (BX). Purebre Afrikaer (AF) a Ngui (NG) cattle represete small-meium a small-frame bree types, respectively. Cows were selecte throughout the trial perio to comply with weight criteria (Table 2). The ifferet hers were kept i separate, but ajacet camps. To reuce possible camp effects, camps were ot allocate i blocks, but were raomly a evely isperse

SA-ANIM SCI 2004, vol 5: http://www.sasas.co.za/popular/popular.html 2 over the whole stuy area. As far as was practically possible cow hers were kept i close proximity to each other. The metabolic postpartum weight (Meisser et al., 1983) of the was use to balace the stockig rates a care was take that stockig rates i ot excee 12 ha per LSU. Table 1 Aual raifall urig the stuy perio Year Raifall (mm) 1995/1996 447 1996/1997 533 1997/1998 589 1998/1999 232 1999/2000 343 2000/2001 846 2001/2002 368 2002/2003 263 Mea 453 Matig took place from the 1 st of Jauary for 63 ays. Heifers (13 to 15 moths ol) were also mate. Pregacy testig was oe urig May or Jue. Calves were bor from the e of October util the mile of December. All calves were weae simultaeously whe the last calf reache 205 ays of age (Jue). Castratio took place urig the weaig phase. All losses were recore. Other her maagemet practices (e.g. ippig, vacciatio) were staarise for all brees. No supplemetary feeig or licks were supplie. Table 2 Mature weight criteria a cow umbers use to select a to balace stockig rates Bree type Abbreviatio Mature weight criteria (kg) Number of Simmetaler crossbre SX > 500 30 Bosmara crossbre BX 450 500 32 Afrikaer AF 400 450 34 Ngui NG < 400 38 Live weights of all aimals were recore at 28-ay itervals after withholig foo a water for at least 12 hours. Live weights of steers were etermie up to 30 moths of age a that of females throughout their lifespa i the her. All calculatios were base o the meas i the tables for the respective bree types. The prouctio potetial of cowhers similar i metabolic weight a LSU (65 LSU) for each bree type subjecte to a weaer (205 ays) as well as a steer (30 moths of age) marketig system was calculate. All refereces to year refer to the year that matig took place. Thus parameters like weaig percetage a weaig weights were calculate i relatio with the cow ata for the matig seaso that the calves were coceive i. Her weaig efficiecy (HWE) a her efficiecy (HE) as summarise i Table 5 was calculate usig the followig equatios: weae HWE = ----------------- X 100 mate This gives a iicatio of the kg calf weae per 100 kg mate. With this formula all factors cotributig to preweaig losses (coceptio rate, abortios, illesses, etc.) are take ito accout. Although the yearly performaces of the ifferet bree types are presete i the tables, it is ot iscusse i etail, as oly the meas were use i calculatios. It thus serves to clarify how the mea values were calculate a to iicate year to year iffereces i performaces.

SA-ANIM SCI 2004, vol 5: http://www.sasas.co.za/popular/popular.html 3 Results No ata are available for NG a SX for 1995 as the NG a some SX were trasferre to the Mara Research Statio i this year. No iitial ata were available for the NG her a ue to aaptatio problems the SX her ha a low pregacy rate. The AF cattle were trasferre from the Mara Research Statio at the e of 2000 a therefore o further ata (after 2000) was available for this bree. Table 3 Pregacy rates of the Simmetaler crossbre, Bosmara crossbre, Afrikaer a Ngui cow hers from 1995 to 2002 Cows Heifers Her Bree Year Preg % N Preg % Preg % Simmetaler crossbre 1995 1996 30 26 86.7 12 9 75.0 42 35 83.3 1997 29 27 93.1 7 5 71.4 36 32 88.9 1998 28 18 64.3 5 1 20.0 33 19 57.6 1999 17 13 76.5 10 7 70.0 27 20 74.1 2000 20 16 80.0 6 5 83.3 26 21 80.8 2001 19 19 100.0 4 2 50.0 23 21 91.3 2002 23 20 87.0 10 5 50.0 33 25 75.8 Mea 166 139 83.7 54 34 63.0 220 173 78.6 Bosmara crossbre Afrikaer Ngui 1995 32 23 71.9 6 1 16.7 38 24 63.2 1996 29 24 82.8 12 7 58.3 41 31 75.6 1997 32 28 87.5 11 8 72.7 43 36 83.7 1998 28 19 67.9 5 2 40.0 33 21 63.6 1999 21 18 85.7 16 7 43.8 37 25 67.6 2000 23 23 100.0 8 7 87.5 31 30 96.8 2001 30 25 83.3 9 4 44.4 39 29 74.4 2002 38 35 92.1 15 2 13.3 53 37 69.8 Mea 233 195 83.7 82 38 46.3 315 233 74.0 1995 30 16 53.3 10 1 10.0 40 17 42.5 1996 30 23 76.7 14 5 35.7 44 28 63.6 1997 34 25 73.5 9 0 0.0 43 25 58.1 1998 24 17 70.8 3 0 0.0 27 17 63.0 1999 18 18 100.0 10 0 0.0 28 18 64.3 2000 27 23 85.2 7 0 0.0 34 23 67.6 2001 2002 Mea 163 122 74.8 53 6 11.3 216 128 59.3 1995 1996 27 26 96.3 5 2 40.0 32 28 87.5 1997 30 30 100.0 13 10 76.9 43 40 93.0 1998 31 26 83.7 7 3 42.9 38 29 76.3 1999 28 26 92.9 13 8 61.5 41 34 82.9 2000 32 30 93.8 14 10 71.4 46 40 87.0 2001 36 34 94.4 12 9 75.0 48 43 89.6 2002 47 41 87.2 17 4 23.5 64 45 70.3 Mea 231 213 92.2 81 46 56.8 312 259 83.0 Pregacy rates varie substatially betwee years for all brees (Table 3). The pregacy rates of NG iffere the least betwee years. The overall pregacy rates of SX a BX were close to the average performace of all aimals over the trial perio. Afrikaer ha lower pregacy rates for most years tha

SA-ANIM SCI 2004, vol 5: http://www.sasas.co.za/popular/popular.html 4 the other types, while SX ha the highest pregacy rates. The pregacy rates of the 13 to 15 moth ol iffere more tha those of the mature. Afrikaer performe the poorest, while NG ha the best coceptio rates. Pregacy rates for a are presete separately to iicate possible explaatios for iffereces betwee bree types. The AF ha lower coceptio rates tha the other brees, but the AF ha such a low pregacy rate that the pregacy rate of the her became eve lower compare to the other hers. Weaig rate as expresse i Table 4, iclues losses such as abortios, istocia, illesses, acciets a theft. I 1997 six NG calves were stole which is why the weaig rate was so low i 1997. The SX a AF hers weae less tha 80% of the calves, as expecte from the pregacy rates, while BX a NG hers weae more tha 80% of the expecte calf crop. Table 4 Weaig rates of the Simmetaler crossbre, Bosmara crossbre, Afrikaer a Ngui cow hers from 1995 to 2001 Simmetaler crossbre Bosmara crossbre Afrikaer Ngui Year A B C A B C A B C A B C % % N % % 1995 21 16 76.2 24 22 91.7 17 12 70.6 1996 35 25 71.4 31 28 90.3 28 17 60.7 28 27 96.4 1997 32 24 75.0 36 28 77.8 25 23 92.0 40 31 77.5 1998 19 16 84.2 21 20 95.2 17 14 82.4 29 28 96.6 1999 20 14 70.0 25 20 80.0 18 17 94.4 34 31 91.2 2000 21 13 61.9 30 26 86.7 40 35 87.5 2001 21 12 57.1 29 27 93.1 43 39 90.7 Mea 169 120 71.0 196 171 87.2 105 83 79.0 214 191 89.3 A Number pregat; B - umber weae; C Percetage weae The very low HWE (Table 5) of the AF her was maily ue to poor reprouctive performace, especially that of the. Although growth rate is also reflecte i HWE, it is ot the major cotributor to HWE. The NG her with the lowest weaig weights ha the highest HWE. The mai cotributors were the high pregacy rates as well as survival rates of calves. Mea live weights at 30 moths of age are summarise i Table 6. This e poit (30 moths) was selecte for calculatios, because it is eeme to be the optimum age for marketig steers from atural sweet pastures. At this age they have graze through two summer seasos urig which the utritioal status of the atural pasture was high eough to sustai high growth rates. Fortuately aimals o ot routiely loose weight o atural sweet pastures urig witer. I fact, they te to gai, but at a slow rate. The followig assumptios were mae i calculatig her prouctivity for both the weaer (Table 7) a the 30 moth ol steer (Table 8) marketig systems: Post-weaig losses are small a the same betwee the ifferet hers a were ot take ito accout. To maitai the same grazig pressure o the pasture, 40% more females ca be kept i the her if a weaer-marketig system is followe tha whe a 30-moth-ol-steer-marketig system is followe. The umber of females mate iclue the 13 to 15 moth ol, as they were iclue i establishig the performace orms. A cow replacemet rate of 20% was use for all bree types a both marketig systems. For the steer marketig systems oly aimals to be markete was take ito accout, but it must take ito accout that although it takes a steer 30 moths to be markete, the cow her is still proucig offsprig a that there will be weaers a 18 moth ol steers i the her at the time of marketig.

SA-ANIM SCI 2004, vol 5: http://www.sasas.co.za/popular/popular.html 5 Table 5 Her weaig efficiecy for Simmetaler crossbre, Bosmara crossbre, Afrikaer a Ngui hers from 1995 to 2001 Cow weight kg Weaig weight kg Bree type Year Simmetaler crossbre 1995 1996 22 802 6 908 30.30 1997 17 896 6 016 33.62 1998 11 598 4 060 35.01 1999 11 138 3 836 34.44 2000 11 378 3 510 30.85 2001 11 132 2 750 24.70 Total 85 944 27 080 31.51 weae/100 kg mate Bosmara crossbre 1995 13 042 4 222 32.37 1996 17 462 7 080 40.55 1997 19 464 6 208 31.89 1998 10 042 4 750 47.30 1999 13 836 4 628 33.45 2000 12 664 6 196 48.93 2001 17 321 5 214 30.10 Total 103 831 38 298 36.88 Afrikaer 1995 11 942 2 222 18.61 1996 13 930 3 098 22.24 1997 17 486 6 180 35.34 1998 11 134 2 744 24.65 1999 11 068 3 344 30.21 2000 2001 Total 65 560 17 588 26.83 Ngui 1995 1996 8 884 4 344 48.90 1997 14 512 5 456 37.60 1998 9 156 4 864 53.12 1999 12 256 5 846 47.70 2000 13 096 6 092 46.52 2001 15 662 6 420 40.99 Total 73 566 33 022 44.89

SA-ANIM SCI 2004, vol 5: http://www.sasas.co.za/popular/popular.html 6 Table 6 Mea live weight (± s..) of Simmetaler crossbre, Bosmara crossbre, Afrikaer a Ngui steers at 30 moths of age Bree type Abbreviatio Live weight (kg) Simmetaler crossbre SX 575.0 ± 57.7 Bosmara crossbre BX 549.7 ± 61.3 Afrikaer AF 460.4 ± 44.3 Ngui NG 440.7 ± 32.8 Mea 508.3 ± 76.0 Table 7 Calculatios for total live weight (kg) prouce aually per bree for the Simmetaler crossbre, Bosmara crossbre, Afrikaer a Ngui cow hers marketig weaers weae /100 kg mate Factor prouce /cow females mate Total kg prouce bull calves prouce culle culle markete culle culle markete Total kg markete Simmetaler crossbre her 31.51 5.25 165.4 50 8 270 4 135 8 4 200 6 1 560 9 895 Bosmara crossbre her 36.88 4.75 175.2 54 9 461 4 731 9 4 275 8 1 792 10 798 Afrikaer her 26.83 4.25 114.0 58 6 612 3 306 10 4225 3 636 8 167 Ngui her 44.89 3.75 168.3 66 11 108 5 554 11 4 125 13 2 249 11 928 Table 8 Calculatios for total live weight prouce (kg) aually per bree for the Simmetaler crossbre, Bosmara crossbre, Afrikaer a Ngui cow hers marketig at 30 moth ol steers females mate % Pregat calves bor % Weae steer markete Steer weight (kg) steers markete culle culle markete culle kg culle markete Total kg markete Simmetaler crossbre her 36 78.6 28 71.0 10 575 5 750 6 3 150 4 475 10 800 Bosmara crossbre her 38 74.0 28 87.2 12 549 6 588 6 2 850 6 2 550 11 988 Afrikaer her 41 59.3 24 79.0 10 460 4 600 7 2 975 2 750 8 325 Ngui her 47 83.0 39 89.3 18 441 7 938 8 3 000 9 2 925 13 863 Discussio Although actual ata were use i all calculatios, iffereces a similarities that occurre allow for comparisos betwee hers, igorig growth rate of the calves. The higher growth rates favourig the larger bree types i ot result i chages i the rakigs of the bree types i terms of kg to be markete. Thus, it is

SA-ANIM SCI 2004, vol 5: http://www.sasas.co.za/popular/popular.html 7 coclue that growth rate of the calves play a mior role i the prouctio performace of the cow her. The two factors that ha the largest effect o the prouctio performace of the cow her were reprouctio rate a calf survival rate. The iffereces i prouctio performace betwee the SX her a the BX her was maily ue to iffereces i their calf survival rate (71.0% vs. 87.2%) as the pregacy rates were similar (78.6% vs. 74.0%). Differeces i prouctio performace betwee the BX a the NG hers were maily ue to iffereces i pregacy rate (74.0% vs. 83.0%) sice the calf survival rates (87.2% vs. 89.3%) were similar. The AF her prouce less tha all the other hers ue to its low pregacy as well as calf survival rates. There seems to be a 10% avatage to the steer prouctio system compare to the weaer marketig system. Possible reasos for this coul be that avatage was take of the rapi growig phases urig the wet summer moths. The maiteace requiremets of a reproucig a lactatig cow her are probably higher tha that of growig aimals. It was ot calculate whether this ifferece i prouctio will be offset by the iffereces i price of the markete proucts (weaers vs. steers). Avatages of a weaer marketig system iclue earlier fiacial returs, reuce risk i losig aimals after weaig a higher per kg prices. Disavatages iclue less flexibility i marketig strategy, setimets may evelop towars prouctive a thus are ot easily sol. Avatages of steer marketig systems iclue: flexible marketig strategies, her umbers ca be more reaily aapte to raifall without reucig cow umbers. Disavatages iclue: loger lag time before fiacial returs are receive, risk of losig aimals after weaig a the log perio it takes after a perio of low raifall a reuctio of her umbers to have marketable aimals. Coclusios Although specific iffereces betwee bree types were observe for various traits uer the stuy coitios, it will ot ecessarily be the case for ifferet evirometal coitios a maagemet practices. This woul have resulte i much better weaig rates for especially the SX her. A ifferet feeig or supplemetatio strategy coul also have ehace the reprouctive performace of the, especially the youg. If the reprouctive performaces of the respective hers are more comparable, the growth rate of the calves will start to play a more proouce role i the prouctio efficiecy of the hers. The characteristics of the respective bree types must also be take ito accout whe eciig o a bree type as well as the prouctio a marketig system that is to be followe. For example, NG calves are ot popular with feelots, while Simmetaler steers o ot fiish well o pastures aloe. This stuy provie prouctio orms that ca be use to calculate ecoomic returs for each iiviual proucer. It was ot oe i this paper, as maagemet, a specifically farm circumstaces, ca iffer substatially betwee proucers. Refereces Acocks, J.P.H., 1988. Vel types of South Africa. Memoirs of the Botaical Survey of South Africa. 57 p. Dekker, B., Kirkma, K.P. & Du Plessis, S.I., 2001. Use of the ry-weight-rak metho of botaical aalysis i semi-ari savaa commuities. Afr. J. Rage For. Sci. 2001, 63-68. Meisser, H.H., Hofmeyr, H.S., Va Resburg, W.J.J. & Pieaar, J.P., 1983. Classificatio of livestock for realistic preictio of substitutio values i terms of a biologically efie Large Stock Uit. Techical Commuicatio No. 175, Departmet of Agriculture, Republic of South Africa.