**2. Beef and dairy cattle production systems**

#### **2.1 Beef production systems**

It was outlined [7] that the system of commercial beef production may be classified into three general categories namely: (i) A cow-calf division wherein weaned feeder calves were raised for further grazing mainly on pastureland and/or feeding with other concentrate diets. (ii) The back-grounding or stocker phase of production wherein body weight was gained by the recently weaned calves, resulting into feedlotready yearlings which also took place mainly on pastureland. (iii) The finishing phase of beef production wherein cattle were fattened for slaughter was carried out mainly intensively under confinement.

The intensive beef production occurs during the finishing stage and also there was the dairy veal production in which beef was produced as a by-product of dairy cows, and these mostly occurred in the developed countries [4]. The researcher [4] reported that in the USA and Europe, there were specialized production, whereby there were mainly beef only, and dairy beef and veal were meant for domestic consumption. In the New Zealand, beef obtained from the dairy industry were produced mainly for export. In the UK, cows raised in the dairying system were increasingly being mated with beef breed sires to upgrade the quantity and quality of beef and veal produced through the use of sexed semen for a particular sex offspring.

*A Global Overview of the Intensification of Beef and Dairy Cattle Production Systems DOI: http://dx.doi.org/10.5772/intechopen.106062*

#### *2.1.1 Cow-calf (beef) system*

The cows and calves were raised under the grazing and rangeland production with strategic nutritional supplementation with concentrate rations and by-products. Their reproductive efficiency could be defined as the weight of calves weaned per cows mated successfully per year. The reproductive rate was thus measured as the percentage of calves weaned relative to the cows mated successfully. It was explained [4] that the maternal genotype was very important and when combined with nutritional and other environmental factors, these go a long way to enhance good reproductive efficiency in beef cattle. Weaned and growing cattle need adequate feed intake from pasture as well as supplements, to ensure rapid growth and improved productivity.

#### *2.1.2 Back-grounding or stocker system*

These involved the practice of grazing and foraging of beef cattle in rangelands over large land areas under harsh environmental conditions of rain and sunshine. The grazing and foraging types included continuous, set-stocked, rotational, strip, strategic, cell or time controlled and planned systems [4]. Genotypes that were reported as used under these beef production systems included the *Bos taurus* breeds and crosses, and the Wagyu and Wagyu crosses.

#### *2.1.3 Feedlot and other intensive beef production systems*

Feedlots were described as the systems of raising cattle to finishing stage, from an initial liveweight of 280 kg until about 400 kg liveweight. Feedlots were used mainly to fatten cattle when the available pasture was inadequate to meet the nutritional requirement of the animals during the period of drought. In two research outcomes [8, 9], it was observed that feedlot diets in the USA and Australia were usually of high protein levels in excess of the requirement for cattle that had reached the fattening or finisher stage. Feedlot diets were used to maximize feed: gain ratio in order to obtain maximum growth rate. In two groups of researches, [10] for Japanese Wagyu and another group [11] for South Korean Hanwoo cattle, it was mentioned that beef under beef production systems were raised to produce beef animals with optimum levels of intramuscular fat development to achieve highly marbled beef. The Wagyu breed cattle kept on feedlots were fed in groups with high energy diets, which were offered twice or thrice daily, from about 11 months of age until 28–30 months at slaughter with water, mineral salt blocks, salt and diuretic provided *ad libitum* [10].

#### **2.2 Dairy cattle production systems**

Dairy cattle could be raised under intensive, semi-intensive or extensive housing systems.

#### *2.2.1 Intensive or confinement system*

Most cattle in the USA and Europe were kept in confinement free-stall, tie-stall and dry-lot or bedded pack systems. In these two countries, only few dairy animals were kept on pastureland. Under the intensive system were the tie-stall and the free-stall systems. Various milking parlour types existed, and the free-stall system gave cows more freedom of movement as compared to the tie-stall [12]. In the intensive management, cows that were raised under confinement generally produced more milk than those raised on pasture. These exotic cow breeds produced milk in the range of 7,000–14,000 kg per cow per lactation of around 305 days. They were milked twice or at most thrice daily. Cows were usually fed total mixed ration made up of forages and concentrates separately. The concentrate diets usually consisted of grains, protein sources, minerals and vitamins. All the lactating cows could be grouped and taken orderly into the milking parlour through holding areas and clean cool water was provided *ad-libitum*. Milking parlour types included the low-cost step-up, herringbone, parallel or rotary [12].

#### *2.2.2 The semi-intensive and extensive systems*

In South America, Australia, New Zealand and India, dairy cattle were raised under semi-intensive and extensive systems, which were the pasture-intensive systems. These were more commonly used rather than the intensive system.

#### **2.3 Housing of dairy calves**

Calves were usually separated from their dams soon after birth and bottle fed with milk or milk replacer (about 4–5 litres/day) twice or thrice daily. Calves were housed in small groups and should have access to clean water *ad-libitum*. Culled calves were usually raised for beef.

#### **2.4 Breeding of dairy cows**

Dairy cows were usually bred at 12–16 months of age. They could calve at around 24 months old, and could be milked as heifers for an average of 305 days in lactation. They could then be made to have a dry period of 50–60 days whereby they were not milked (during the third trimester pregnancy period) before they calved, and thereafter to start another reproductive cycle for another lactation period.
