Thesis (MPhil)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The primary objective of today's pig producer is to maximize profit received per unit of pig space provided in a given facility. There are certain management strategies that a farmer can implement to ensure this. The goals of such strategies include maximizing performance and implementing proper pig flow schedules and to make sure current facilities are performing at maximum capacities or are better utilized. Labour in South Africa is still relatively inexpensive, but time is money. Feeding and cleaning small pens are time consuming and expensive to maintain (more feeders and water nipples, gates, walls and heating). Proper management of facility space is vital to remain competitive in today's pig industry. The amount of floor and feeder space provided within an animal's environment could vastly influence pig performance and profitability. Crowding pigs has a negative effect on Average Daily Gain (ADG) and overall performance. Conversely, facility cost per pig increases as additional space is provided, therefore, in the interest of pen efficiency, the space that allows for maximum individual performance may not be optimal for maximizing profit. Factors such as cleaning and cleaning time also have an effect on profitability. Another concerning factor associated with maximizing performance and maintaining the pig flow of a facility is that of Body Weight (BW) variation. Having uniform pigs at 70 day, post-weaning has been a major goal to ensure maximum performance in finishers. Numerous contradictions regarding the growth of piglets post-weaning (especially the effect of group size and floor space allowance) still exist in literature. Also, in South Africa, the majority of pig producers still believe that individual litters or small groups of pigs in the growers perform better and are the most economical production method. Therefore, this trial was performed to investigate the raising of large groups (200-450 pigs/group) compared to small groups (10-20 pigs/group) on their performance until 70 days when they were moved to growers. Over a period of two years, data was collected on a commercial 1200 sow unit in the Western Cape, South Africa. Crossbred pigs (n=14657; Landrace x Large White; both gilts and barrows) weaned at 19 to 24 days with average weaning weight of 5.11 kg were randomly divided into different group sizes. Groups of 10, 20, 200 and 450 were grouped together and were all given the same feed ration. The groups were housed in different buildings naturally ventilated with no artificial heating and with solid flooring. Pelleted diets were formulated (Startrite followed after two weeks with Expresweaner) by Meadows Feed Mills (Paarl, Western Cape) for weaned piglets and fed to all the piglets. The animals received the diets and water ad lib. All the piglets were weighed before being placed into the different pens (initial weight). After 69 - 72 days the piglets were weighed again (final weight). The pigs were weighed as a group and not individually. The data was statistically analysed by determining averages and standard deviations for each house. The results of this trial clearly indicate that raising piglets in larger groups does not negatively affect the performance of the piglet in terms of ADG and mortality. In larger groups, the less time (labour time) spent cleaning and the fewer feeders needed, also results in lower production costs. In today's economical environment, the producer that can lower his production cost while maintaining production standards has a significant advantage. Therefore, it is believed that by grouping pigs in larger groups, labor time (in terms of cleaning) can be reduced, and will lower production cost without reducing production standards. / AFRIKAANSE OPSOMMING: Die hoofdoel van vandag se varkprodusente is om maksimum wins per eenheid vark spasie te maak. Daar is sekere produksietegnieke wat 'n produsent kan volg om dit te verseker. Die doel van die tegnieke is om te verseker dat maksimale produksienorme en doeltreffende vark vloei gehandhaaf word asook dat huidige fassiliteite optimum benut word. Arbeid is nog relatief goedkoop in Suid-Afrika (SA), maar tyd is geld. Die voeding en skoonmaak van klein hokke is tydrowend en duur om te onderhou (meer voerbakke, waternippels, hekke, mure en verhitting). Om koste-effektief te boer, moet goeie bestuur van oppervlakte toegepas word. Die hoeveelheid oppervlakte en voerspasie beskikbaar, het 'n groot invloed op die produksievermoë en winsgewendheid van die varkies. Om te veel varkies per area aan te hou, het 'n negatiewe effek op die Gemiddelde Daaglikse Toename (GOT) en algehele prestasie. Soos die vloerspasie per varkie vergroot, neem die produksiekoste ook toe en is die area wat benodig word om varkies maksimaal te laat produseer, nie altyd die winsgewenste nie. Skoonmaak en skoonmaaktyd het ook 'n invloed op winsgewendheid. Die ideaal is om uniforme varkies op 70 dae te produseer. 'n Variasie in gewig is rede tot kommer, aangesien dit die produksie in die groeiafdeling beïnvloed. Verskeie teenstrydighede aangaande die groei van varkies naspeen (veral die effek van goepgrootte en vloerspasie) bestaan steeds in die literatuur. In SA is die meeste produsente ook nog onder die indruk dat klein groepe varkies beter presteer as groot groepe en die mees ekonomiese metode is om te boer. Daarom is 'n proef geloods om vas te stel hoe die produksie verskil tussen klein groepe (10 - 20 varkies per groep) teenoor groot groepe (200 - 450 varkies per groep) tot 70 dae ouderdom wanneer hulle na die groeiafdeling skuif. Oor 'n periode van twee jaar is data gekollekteer op In kommersiële 1200 sog-eenheid in die Wes-Kaap, Suid-Afrika. Kruisgeteelde varke (n=14657; Landras x Groot Wit; beide beertjies en soggies) is gespeen tussen 19 en 24 dae, met 'n gemiddelde speen gewig van 5.11 kg en ewekansig verdeel in verskillende groepgroottes. Groepe van 10, 20, 200, en 450 varkies was saamgegroepeer en het almal dieselfde dieet ontvang. Die groepe is in verskillende geboue gehuisves en al die geboue het soliede vloere gehad en was natuurlik geventileerd met geen kunsmatige verhitting nie. 'n Verpilde dieet is deur Meadows Voermeule (Paarl, Wes-Kaap) geformuleer (Startrite vir twee weke en dan Expresweaner vir die res van die proef). Die varke het die dieet en water ad lib ontvang. AI die varkies is geweeg voordat hulle in die verskillende hokke geplaas is (aanvangsmassa). Na 69 - 72 dae is die varkies weer geweeg (eindmassa). Die varkies is as 'n goep en nie individueel geweeg nie. Die data is statisties verwerk deur gemiddeldes en standaard-afwykings vir elke huis te bepaal. Die resultate van hierdie proef het duidelik aangetoon dat die grootmaak van varkies in groter goepe nie die produksie van die varkies (i.t.v. GOT of mortaliteit) nadelig beïnvloed het nie. In groter goepe is minder tyd nodig om die hokke skoon te maak en is minder voerders nodig. Dit lei tot 'n verlaging in produksiekoste. Deesdae het die produsent wat sy produksie koste kan verlaag, sonder om produksiestandaarde in the boet, 'n aansienslike voorsprong. Die gevolgtrekking word dus gemaak dat deur varkies in groter groepe aan te hou, arbeid (in terme van skoonmaak) verminder kan word en dus kan produksiekoste verminder sonder dat produksie self afneem.