Tick susceptibility and its effects on growth performance and carcass characteristics of Nguni, Bonsmara and Angus steers raised on natural pasture

Abstract

The objective of the current study was to compare tick loads, growth and carcass characteristics of dipped and non-dipped Nguni, Bonsmara and Angus steers raised on natural pasture. One hundred 7-month-old castrated weaners were kept at the University of Fort Hare Farm for 12 months. There were 30 weaners each of Angus and Bonsmara, and 40 weaners of the Nguni breed. Half the Bonsmara, Angus and 14 Nguni weaners were dipped every fortnight. The rest were not dipped. Monthly weights and tick counts under the tail, on scrotum, belly, sternum and ears of the steers were recorded. The dipped Nguni steers had lowest (P , 0.05) tick counts, and the non-dipped Angus steers had the highest (P , 0.05) tick counts. There were more ticks (P , 0.05) during the warm wet season than during the cool dry season. Ears had the highest (P , 0.05) tick infestation. Average daily gain (ADG) was similar (P . 0.05) among the three breeds. The non-dipped Bonsmara steers had the heaviest (P , 0.05) carcasses (142 6 5.4) while the non-dipped Nguni steers had the lightest (P , 0.05) carcasses (111 6 4.5 kg). The non-dipped Bonsmara had the highest (P , 0.05) eye muscle area (3996 6 120.8 mm 2 ) while the nondipped Angus had the smallest (P , 0.05) eye muscle area (3291 6 210.6 mm 2 ). The non-dipped Bonsmara also had the highest (P , 0.05) dressing percentage (53.8 6 1.01) while the non-dipped Nguni had the lowest (P , 0.05) dressing percentage (50.3 6 0.84). The current study has shown that while the non-dipped steers had higher (P , 0.05) tick loads than the dipped steers, their growth and carcass characteristics were similar (P . 0.05). The study has also shown that, despite being a smallframed breed, the Nguni steers had similar (P . 0.05) ADG to the large-framed Bonsmara and Angus steers. Therefore, the Nguni cattle have the potential to produce organic beef. However, a reasonable assessment of organic beef production potential of the Nguni requires an evaluation of its meat quality traits under natural pasture.

Sensory evaluation and its relationship to physical meat quality attributes of beef from Nguni and Bonsmara steers raised on natural pasture

“…Assessment of meat production in the communal areas should include meat acceptability. Previous studies showed that there were no differences between beef from Nguni and Bonsmara steers in terms of their physical and histological meat quality characteristics (Muchenje et al, 2008a); while the Nguni had low tick loads and the Bonsmara had better carcass characteristics under natural grazing (Muchenje et al, 2008b), the Bonsmara steers were more stress-responsive at slaughter than the Nguni steers (Ndlovu et al, 2008). These studies however did not include sensory evaluation and its relationship with physical meat attributes.…”

“…The indigenous Nguni cattle breed of South Africa is small to medium sized, but adapted to harsh environments Muchenje et al, 2008a and2008b).…”

“…The Bonsmara competes favourably with European beef cattle while withstanding subtropical conditions, such as high temperatures, ticks and most tick-borne illnesses Muchenje et al, 2008a and2008b). They are well muscled with high beef yield and quality.…”

Stress reactivity and its relationship to beef quality in Nguni steers supplemented with Acacia karroo leaves

“…The Nguni breed has been shown to be resistant to nematodes (Xhomfulana et al, 2009), ticks (Muchenje et al, 2008a) and tick-borne diseases (Marufu et al, 2010), tolerant to pre-slaughter stress (Ndlovu et al, 2008;Muchenje et al, 2009) and produce meat of comparable quality to established beef breeds under rangeland conditions (Muchenje et al, 2008b). Although rangeland energy and mineral supplies in the dry seasons are sufficient to meet the production requirements of Nguni cattle (Mapiye et al, 2010a), they lose -E-mail: cmapiye@yahoo.co.uk body condition and weight in the same season as a consequence of limited protein supply (Mapiye et al, 2010b).…”

Population structure and genetic trends for indigenous African beef cattle breeds in South Africa

“…In South Africa, indigenous cattle breeds such as the Afrikaner, Drakensberger and Nguni breeds have made major contributions to livestock production because of their ability to adapt and produce in different systems (Muchenje et al, 2008;Beffa et al, 2009;Matjuda et al, 2014 ). The Afrikaner, Drakensberger, Nguni and Tuli cattle breeds have a long history of participation in animal recording and have an average complete pedigree recording in the first generation varying from 88.5% for the Nguni to 92.5% for the Afrikaner (Table 2).…”