Orientador: Roberto de Oliveira Roça / Banca: Simone Fernandes / Banca: Marcelo Henrique de Faria / Resumo: Alimentos com menores teores de gordura e ou com melhor perfil de ácidos graxos são o principal enfoque do mercado para produtos de origem animal. Portanto, este trabalho objetivou avaliar a inclusão de três fontes de óleo vegetal na dieta de cabras em lactação sobre a composição, o perfil de ácidos graxos e os parâmetros sensoriais do iogurte produzido com o leite destas cabras. Foram utilizadas 32 cabras da raça Anglo-nubiana distribuídas em quatro tratamentos: dieta controle versus com inclusão de 3% de óleos de canola, girassol e soja. Foram avaliadas as influências de tratamentos e períodos de lactação sobre a composição, o perfil de ácidos graxos e os parâmetros sensoriais do iogurte. Para determinação dos constituintes, foram colhidas amostras aos 21, 51, 81 e 111 dias de lactação e para o perfil de ácidos graxos aos 21 e 111 dias de lactação. A produção leiteira em 120 dias de lactação foi de 182,75 kg e não houve diferença para os tratamentos. Os constituintes, não foram influenciados pelos tratamentos, entretanto o teor de proteína apresentou efeito para período. Para gordura e extrato seco desengordurado houve interação entre tratamento e período. A inclusão de óleos de girassol e soja promoveu aumento no teor total de ácidos graxos poli-insaturados (AGPI) e de ácido linoléico conjugado (CLA). O índice de aterogenicidade (IA) melhorou com a adição de óleo na dieta dos animais, sendo mais acentuada nos tratamentos com óleo de girassol e soja. Para a análise sensorial os iogurtes dos tratamentos com inclusão de óleos de girassol e soja não apresentaram diferença do tratamento controle (sem adição de óleo) para o parâmetro sabor, já o iogurte do tratamento com óleo de canola demonstrou diferença. Para a consistência todos os tratamentos com adição de óleo foram diferentes do tratamento controle, sendo ainda o iogurte ... / Abstract: Foods with lower fat and or better fatty acid profile are the main focus of the market for animal products. Therefore, this study aimed to evaluate the inclusion of three vegetable oil sources in the diet of lactating goats on the composition, fatty acid profile and sensory parameters of yogurt made from milk of these goats. Were used 32 Anglo-Nubian goats distributed in four treatments: control diet versus with inclusion of 3% of canola, sunflower and soybean oil. The influences of treatments and lactation periods on the composition, fatty acid profile and sensory parameters of the yoghurt were evaluated. For determination of the constituents, samples were taken at 21, 51, 81 and 111 days of lactation and the profile of fatty acids at 21 and 111 days of lactation. Milk production in 120 days of lactation was 182.75 kg and there is no difference to the treatments. The constituents were not affected by the treatments, but difference on the protein content was seen at period. For fat and defated dry extract was interaction between treatment and period. The inclusion of sunflower and soybean oils promoted an increase in the total content of polyunsaturated fatty acids (PUFA) and conjugated linoleic acid (CLA). The index of atherogenicity (IA) improved with the addition of oil in the diet of animals, being more pronounced in the treatments with sunflower and soybean oil. For sensory analysis of the yogurt the treatments including sunflower oil and soybean showed no difference from the control treatment (no addition of oil) for taste parameter but yogurt of the treatment with canola oil showed a difference. For consistency all treatments with the addition of oil were different from the control treatment, still yogurt from the treatment with canola oil the less accurate than the control. These results suggest that the addition of 3% of vegetable oils in the diet of lactating goats improves ... / Mestre

Effects of Acacia karroo supplementation on meat quality of Xhosa Lop-Eared goats The objective of the study was to determine the effects of A. karroo supplementation on the quality of meat from Xhosa lop-eared goats. Eighteen castrated 4-month-old Xhosa lop-eared male kids were kept at the University of Fort Hare Farm until slaughter. At the beginning of the experiment the goats had a mean body weight of 13.5 ± 0.31 kg (mean ± S.E.) and a mean body condition score (BCS) of 3.3 ± 0.16 (mean ± S.E.). From birth until weaning the kids were kept on natural pastures with their mothers. After weaning the goats were housed in an open sided barn for a period of 60 days, and were fed 500 g/head/day of Medicago sativa hay covering their maintenance and growth needs. For the purpose of the experiment, the goats were randomly divided into two balanced treatment groups of nine goats each, supplemented group (AK) and non-supplemented group (NS). The supplemented group received an additional 200g per head per day of fresh A. karroo leaves collected each day for two months. Supplementary feed was given to the goats individually in feeding troughs. The kids were slaughtered at 60 days old and samples for meat quality assessment were taken from the Longistimus dorsi muscle. The effect of A. karroo supplementation on meat quality measurements such as ultimate pH, colour and cooking losses of meat from indigenous Xhosa lop-eared goats were determined. The effect of A. karroo supplementation on the consumer sensory characteristic scores of the meat from the indigenous Xhosa lop-eared breed was also determined. There was a significant effect of the A. karroo supplementation on the meat quality measurements except for L* and a* colour coordinates. Meat from the A. karroo supplemented goats had lower pH and cooking loss scores than that of the non-supplemented goats. Acacia karroo supplementation improves meat tenderness and juiciness. There were no significant effects of A. karroo supplementation on the flavour and off- iv flavours of the meat from the supplemented goats. However, thermal preparation and consumer background had a significant effect on the meat sensory characteristics. The cooked meat had significantly higher sensory scores than the roasted meat. Female consumers reported higher sensory scores than male consumers. Consumers of different tribes and ages also reported significantly different sensory scores of meat from indigenous Xhosa lop-eared goats. Therefore, this study indicated that A. karroo supplementation can be fed to the Xhosa lop-eared goats to improve their meat quality.

Small-scale goat farmers from south-western KwaZulu-Natal Province, South Africa, identified gastrointestinal helminths, dry-season feed scarcity and poor reproductive performance as major production constraints and highlighted the paucity of information on goat health and management. The research and extension processes adopted to address these problems comprised on-station experimentation, followed by on-farm validation combined with the participatory dissemination of both study findings and relevant information on goat health care. The approach included the use of the FAMACHA© system to assess anaemia, a characteristic symptom of infection with the gastrointestinal nematode, Haemonchus contortus (Rudolphi, 1803). On-station experimentation indicated that urea-molasses block supplementation during the dry, winter season was a cost-effective option. Unfortunately, when tested on-farm, the value of such supplementation proved inconclusive, possibly due to low block consumption and further research into alternative and palatable protein supplements for goats is suggested. However, tactical anthelmintic treatment with ivermectin effectively reduced faecal egg counts and is recommended, as is concurrent symptomatic anthelmintic treatment, as determined by the FAMACHA© system, since this practice appeared to improve reproductive capacity. Investigations to better adapt the FAMACHA© system to goats is, however, recommended. A flexible training framework was developed with the collaboration of the farmers, providing them with advice on goat health and management. This ‘hands-on’ approach encompassed regular meetings geared to the farmers’ current expertise and exploited the on-farm experimentation as a training vehicle. The process nurtured local farmer ‘champions’, strengthened the extension skills of researchers and technicians and incorporated the development of a Goatkeepers’ animal health care manual. Indications are that the use of such an approach has considerable potential for the development of goat farming. Moreover this process, which is relatively novel for South Africa, is equally applicable to other similar agro-ecological zones. Access to veterinary and agricultural inputs in areas where communal grazing is practised could be vastly improved and a case is made for universities, researchers, extensionists and farmers to collaborate to encourage the long-term sustainable development of these communities. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.

Department of Animal Science / PhD (Agric)