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Effect of pomegranate (Punica granatum L) peel powder meal on growth performance, gut integrity, haemato-biochemical indices, meat, and bone quality of broiler chickens

  • Authors: Akuru, Eunice Amaka https://orcid.org/0000-0002-3093-0247
  • Date: 2022-04
  • Subjects: Broilers (Chickens) , Meat -- Quality
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10353/23611 , vital:58218
  • Description: The objective of the current study was to investigate the overall response of broiler birds to varying dietary levels of pomegranate (Punica granatum L) peel powder meal (PPPM). A total of 432-day-old Cobb 500 broiler chicks were randomly divided into six experimental groups of four replications with 18 birds per replicate in a completely randomized design (CRD). The birds were fed isonitrogenous and isocaloric experimental diets designated as: T1-control diet with 0percent additives (negative control; NEGCON); T2- control diet supplemented with α-tocopherol acetate at 200g per ton (positive control; POSCON): T3, T4, T5 and T6-control diet supplemented with 2, 4, 6 and 8g/kg PPPM (PPPM2, PPPM4, PPPM6, PPPM8). The phytochemical, nutritional and antioxidant properties of the pomegranate peel powder were determined. Results showed that the South African-grown pomegranate peel (“Wonderful” variety) had rich protein and trace mineral contents. Higher (p < 0.05) antioxidant and hepatic anti-lipid peroxidative activities were recorded in the ethanol and acetone extracts than the water extract, whereas the three extracts had no toxic effects on liver and kidney cells (p > 0.05). The dietary effects of PPPM supplementation on growth performance, digestibility, carcass, and organ weight indices of Cobb 500 birds were determined. The POSCON diet enhanced (p < 0.05) feed conversion ratio (FCR) at week 3. The average final body weight and average daily weight gain were highest (p < 0.05) in birds fed PPPM2 and PPPM4 diets, whereas birds fed PPPM2 diet had enhanced (p < 0.05) FCR and protein efficiency ratio when compared with birds on POSCON. Thigh and breast weights were highest (p < 0.05) in birds on PPPM4 and PPPM8 diets, whereas birds fed PPPM4 diet had enhanced (p < 0.05) nutrient digestibility compared with those on POSCON. The antioxidant status and breast meat quality of Cobb 500 broiler birds fed diets supplemented with PPPM were determined. Meat from birds fed PPPM8 diet had the highest (p < 0.05) thawing loss, while cooking loss was lowest (p < 0.05) in the PPPM2 group. The highest (p < 0.05) ability to scavenge ABTS [(2, 2-azinobis (3ethylbenzothiazoline-6 sulfonic acid))] radical cation (ABTS+) was recorded in the PPPM2 and PPPM4 meat while PPPM8 meat had increased (p < 0.05) catalase activity. The fatty acid composition, oxidative status, and drip loss in breast meat of Cobb 500 broiler birds fed graded levels of PPPM was determined. Meat from birds fed PPPM4 diet had the lowest (p < 0.05) margaric (C17:0) and arachidic (C20:0) acids, while meat from birds fed PPPM8 diet had higher (p < 0.05) levels of eicosadenoic (C20:2, n-6) and arachidonic (AA, 20:4) acids. The POSCON had higher (p < 0.05) ability to reduce TBARS levels in meat on day-1 and day-16 of storage than the NEGCON and PPPM diets, whereas TBARS levels were lowest (p < 0.05) in PPPM6 meat on day-16. The gut pH, histology, haematology, serum-biochemical indices, and bone quality parameters of Cobb 500 broiler birds fed diets supplemented with PPPM was determined. Birds fed POSCON, PPM2 and PPPM4 diets had the lowest (p < 0.05) pH in the duodenum, jejunum, and caecum, whereas duodenal pH values were lowest (p < 0.05) in birds fed PPPM2 and PPPM4 diets compared with birds on NEGCON. Birds fed PPPM4 diet had the highest (p < 0.01) duodenal, jejunal and ileal villi height (VH), and the highest (p < 0.01) VH to crypt depth (CD) ratio in the duodenum, jejunum, and ileum. The lowest (p < 0.05) CD in the duodenum, jejunum and ileum was also recorded in birds fed PPPM4 diet. Birds fed PPPM8 diet had higher (p < 0.05) values for white blood cell count, red blood cell count, haemoglobin concentration and packed cell volume, whereas the lowest (p < 0.05) concentration of serum aspartate transaminase was recorded in birds fed PPPM4 diet. Birds on PPM4 diet had longer (p < 0.05) bones. Bone weight and bone breaking strength were highest (p < 0.05) in birds fed PPPM8 diet. Tibia zinc and iron concentrations increased as the inclusion levels of pomegranate peel powder meal increased. It was concluded that broiler birds require 4 g/kg pomegranate peel powder for enhanced growth performance, nutrient digestibility, gut histology, quality, and antioxidant enzyme activity of meat, whereas 8 g/kg pomegranate peel powder meal supplementation is required for enhanced heamato-biochemical indices, bone quality, fatty acid composition and lipid peroxidative parameters in broiler birds. , Thesis (PhD) -- Faculty of Science and Agriculture, 2022
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  • Date Issued: 2022-04

Beef quality, oxidative stability and fatty acid composition of Nguni heifers fed diets with incremental levels of Opuntia ficus-indica (cactus) cladodes

  • Authors: Mkhosi, Silungile
  • Date: 2020
  • Subjects: Meat -- Quality
  • Language: English
  • Type: Thesis , Masters , MSc (Animal Science )
  • Identifier: http://hdl.handle.net/10353/18732 , vital:42728
  • Description: The objective of the study was to determine meat quality, fatty acid (FA) composition and shelf-life stability of longissimus muscle of Nguni heifers fed incremental levels of Opuntia ficus-indica (cactus) cladodes. A total of 32 heifers aged 36 months were allocated randomly to four dietary treatments: 10% cactus, 20% cactus, commercial and control diets for 90 days. The longissimus thoracis et lumborum (LTL) samples were taken from each carcass for the determination of meat quality, retail shelf-life stability and FA composition. Diet had no effect (P > 0.05) on pH and drip display, however, there was an increase in drip display with ageing time (P ≤ 0.05). Meat colour attributes (L* a* b* and C*) were influenced by diet, with 20% cactus diet having lower L* values compared to other diets (P ≤ 0.05). During a 14-day retail display, a diet  day interaction was observed for hue angle with the cactus diets having the lowest values at day 14 of display compared to the other diets (P ≤ 0.05). Differences in meat from heifers fed different diets were observed with 20% cactus accounting for significantly (P ≤ 0.05) higher levels of deoxymyoglobin and the lowest levels of oxymyoglobin. Thawing loss and Warner Bratzler shear force decreased (P ≤ 0.05) with ageing period. Meat from heifers fed cactus diets had lower (P ≤ 0.05) proportions of oleic acid (C18:1n9c) and total MUFA, higher (P ≤ 0.05) proportions of total SFA, C15:1, C17:1, linoleic acid (C18:2n6c) and total PUFA. The control diet produced meat with the highest thiobarbituric acid reactive substances (TBARS) values compared to other diets (P ≤ 0.05) and with ageing TBARS values increased (P ≤ 0.05). Diet showed an effect (P ≤ 0.05) on sensory attributes such as overall tenderness and mouth feel with cactus diets accounting for lower scores. However, juiciness, overall tenderness, grassy and animal like attributes increased with ageing (P ≤ 0.05). Inclusion of cactus in the diet did not produce any adverse effects on meat quality, fatty acid composition, lipid oxidation and sensory quality. Therefore, it can be concluded that inclusion of cactus in Nguni heifer finisher diets up to 20% can improve meat quality.
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  • Date Issued: 2020

Muscle nanostructure, fat colour related fatty acids and Check-All-That-Apply visual profiling of South African A2 beef longissimus

  • Authors: Soji, Zimkhitha
  • Date: 2019
  • Subjects: Meat -- Quality
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/15264 , vital:40332
  • Description: The main objective of this study was to determine the effect of muscle nanostructure on tenderness, fat colour related fatty acids and Check-All-That-Apply visual profiling of South African A2 beef longissimus. Fifty two A-class steers (n=52) of five breeds (Bonsmara (n=19), Beef master (n=7), Hereford (n=9) and Simbra (n=17)) typically processed in different South African feedlots were studied. The animals were humanely slaughtered at an abattoir following the commercial standard procedures. Fat colour measurements (CIE b*) were taken at the P8 site on hot carcasses at the abattoir. Carcass mass (warm and cold) was recorded at the slaughter line before chilling (warm) and after chilling (cold) while pH0 and temperature were measured at 45 minutes post-mortem on the Longissimus thoracis et lumborum (LTL) muscle. Thereafter, a 20 g subsection of the LTL muscle on the left side of each carcass was sampled for muscle nanostructure analysis. At 24 hours post-slaughter, ultimate pH (pH24) was measured, further subsections of the LTL muscle (20 g) were harvested for further muscle nanostructure analysis and 2.5 kg of the LTL muscle was also harvested for analysis of tenderness, fatty acids and sensory evaluation. The muscle nanostructure (myofibril diameter (MYD), myofibril spacing (MYS), muscle fibre diameter (MFD), muscle fibre spacing (MFS) and sarcomere length (SL)) was analysed using the scanning electron microscope (SEM) while tenderness was measured using Warner Bratzler Shear Force after 45mins, 24hrs, 3 and 7 days aging period at -20 ºC refrigerator temperature. Some proximate fractions (total extractable intramuscular fat (Fat %), Fat Free Dry matter (FFDM %) and Moisture content) and fatty acid profile were measured using extracted fat and fatty acid indices (desaturase index, atherogenicity index) were calculated. Lastly a Check-All-That-Apply visual profiling method rated by an 80-member consumer panel was done to assess consumer meat preferences and perceptions of Bonsmara, Hereford and Simbra A2 fresh steaks. At 45mins post-slaughter breed affected (P<0.05) MYD and MYS, while at 24hrs breed affected MFD and MFS only. Early post-mortem pH (pH0) had no effect on the muscle nanostructure and tenderness while ultimate pH (pH24) affected MYD and MYS only. Muscle temperature at 45mins affected (P<0.05) the MYD, MFD and MFS, while 24hrs muscle temperature affected (P<0.05) MYD only. Tenderness was not related to the muscle nanostructure early post-mortem and there was no uniformity on the changes in muscle nanostructure and tenderness from early post-mortem to 24hrs against the multifaceted carcass mass, muscle pH and temperature effects. During ageing, breed affected the MYD and MYS at 45mins, while at 24hrs in addition to the myofibril structure breed also had an effect on muscle fibre bundle characteristics (MFD and MFS). The changes in MYD, MYS and MFS became constant on day 3 while variations in the MFD still progressed. There was no uniformity on the SL pattern during ageing and a very weak linear relationship between tenderness, SL, MFD and MFS was observed. Notably there was also no uniformity on how the muscle texture features; including the surface structure, fibre separation, and the mechanism of muscle contraction and relaxation; changed throughout the ageing period across and within the breeds. Moreover, breed had a significant effect on pentadecyclic acid, total saturated fatty acids (SFA) and docosahexanoic acid. Differences (P<0.05) in SFA, monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), n-6, n-3, fatty acid ratios, and desaturase index were observed among the white, creamy-white and creamy fat colour. The distribution of fatty acid classes was SFA>MUFA>PUFA in descending order of concentrations of mean values (44.19:40.06:15.75, respectively), while the n-6: n-3 ratio was 12:1. In sensory evaluation, consumers indicated how they would prefer to pay premium for meat with guaranteed muscle and fat colour, low fat content, high marbling and tenderness. Consumers observed breed differences (P<0.05) in muscle fibre separation and muscle colour. The overall liking of each attribute was more on moderate bright cherry red lean colour, moderate yellow fat, very abundant marbling and slight separation of muscle fibres. Differences on discrete liking of each attribute among consumers had an effect on the overall liking of each steak with Hereford steaks being more preferred by consumers. It was concluded that meat from beef animals within the same feeding regime has a different fatty acid composition owing to different breed synthetic pathways and feed ingredients and that meat tenderness is not affected by the muscle nanostructure early post-mortem. However, during ageing, meat tenderness is directly linked to breed related myofibril structure changes in particular the myofibril diameter, spacing between myofibrils and their interaction; while the muscle texture features, fibre diameter, spacing between muscle fibres and sarcomere length explain the non-uniformity of beef tenderness. Also the organoleptic and health related quality of meat assumed more importance among consumers in sensory evaluation. Thus meat classification systems should include more credence aspects or indicators that support credence quality of meat
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  • Date Issued: 2019

Nutritional quality of sausage made with edible meat waste and the perception of consumers on offal product in Eastern Cape Province, South Africa

  • Authors: Oluwasegun, Babatunde Alao
  • Date: 2019
  • Subjects: Meat -- Quality
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/19021 , vital:40094
  • Description: Meat processing at the abattoir provides meat by product and waste while, the major part of the muscle which constitutes a third is edible. The edible by products (EBP) of meat have a notable position in our day-to-day life and are used in diverse forms. However, the quality of offal meat may differ according to intrinsic and extrinsic attributes that may occasionally be shaped by the attitude of consumers towards the products. Therefore, the first objective of this thesis focused on features that might influence consumer preferences and their perception of offal meat. A total of 202 consumers from three Municipalities in Amathole District were randomly sampled using exponential nondiscriminative snowball sampling. Data were gathered through a structured questionnaire containing open ended and closed ended questions. The study showed that consumers were more influenced by the freshness, price and availability of the product and these factors are used to determine the purchase outlet. Differences were observed in the offal meat consumption between the age groups. Age groups 25-34 (29.7%) and 35-44 (27.4%) showed the highest offal meat consumption, while the decline was observed in age groups of 55-64 (11.9%), 65- 74 (5.9%) and 75-85 (0.01%) respectively. The most preferred purchase point for offal meat in this study was in butcheries. However, it was observed that the factors influencing offal consumption in Amathole District were similar to meat consumption except that, offals were mainly purchased at butcher shops. The second objective in this study was to determine the sensory characteristics and consumer acceptance of sausages with 10% fat, 30% edible meat waste and 50% edible meat waste. Sensory descriptive attributes such as appearance, texture, colour, taste, flavour and overall acceptance of the sausage were evaluated by sensory panel (n = 60). The sensory panel comprised of students from undergraduates, post-graduates, post-doctoral fellows and lecturers at the University of Fort Hare. The findings of the study indicated that 50% replacement of xiii edible meat waste was similar to the commercial 10% fat with regard to several sensory attributes and pooled liking. Therefore, the utilization of the edible meat waste in production of sausages has the potential to increase profitability in meat industry and minimise meat waste in the industry. However, the cooking method that was more acceptable to consumers in this study was using the microwave as compared to oven-grilling. Furthermore, the effects of different cooking methods (microwave and oven-grilling) on proximate and mineral composition of the formulated sausages were determined. However, the cooking process appeared to have a significant effect on most of the minerals in the sausage. The cooking methods had a significant effect at P <0.01 on the nutrients composition of the formulated sausage. It was observed that the nutritional values of the sausage was better preserved after the cooking process due to higher mean values obtained after cooking. The mean values for calcium (173.1, 221.76, 231.29), potassium (444.57, 158.58, 156.67), magnesium (84.43, 257.97, 127.27), zinc (52.94, 35.27, 27.13), copper (8.8, 7.07, 4.44), manganese (8.74, 0.65, 0.08), sodium (589.42, 604.45, 529.79) and iron (63.3, 85.38, 74.81) in cooked. And the mean values for calcium (286.18, 132.18, 114.79), potassium (206.64, 113.83, 207.81), magnesium (189.89, 33.97, 48.11), zinc (61.05, 28.09, 26.44), copper (2.92, 2.73, 3.89), manganese (1.42, 0.11, 0.35), sodium (566.47, 530.79, 527.35) and iron (77.56, 58.68, 45.42) in uncooked sausage varied greatly among the treatments. Although, the disparities in the mineral content may be attributed to the different edible meat waste from different parts of the cattle which are either from feedlot or pastured based. In regard to the results obtained from proximate and mineral composition, microwave cooking method was found to be the best cooking technique for healthy eating. Finally, the effect of frying with two different oils (sunflower oil and olive oil) on the fatty acid composition of sausage made with edible meat waste was examined. The results revealed that beef sausage containing 70% edible meat wastes and 30% beef (T1) had a higher fat content xiv (25.7%±0.83%) than other treatments. On the other hand, beef sausage fortified with 10% fat and 90% beef (T3) had the lowest fat content but highest FFDM (55.85±0.57%) and moisture content (69.15±0.62) than other treatments. Despite the increase in omega-3: omega-6 fatty acid ratio in the sausage treatments after cooking, the mean value of omega-3: omega-6 fatty acid ratio was greater than 1:5 (0.2) which is within the FAO/WHO recommended range. The omega-3: omega-6 association is well-known for its importance in the diet because it is a key factor for balanced eicosanoid production in the living organism. The significant reduction in saturated fatty acids after cooking showed that there could also be a positive influence on the human health if consumed. Therefore, it may be concluded from the findings of the study that sausage made with edible meat waste as fat replacer is safe for human consumption.
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  • Date Issued: 2019

Effects of dietary inclusion of Moringa oleifera leaf meal on growth performance, physico-chemical attributes, oxidative stability and sensory quality of pork

  • Authors: Nduku, Xola Pauline
  • Date: 2014
  • Subjects: Pork -- Quality , Food -- Sensory evaluation , Fatty acids , Moringa , Meat -- Quality
  • Language: English
  • Type: Thesis , Masters , MSc Agric (Animal Science)
  • Identifier: vital:11836 , http://hdl.handle.net/10353/d1021281 , Pork -- Quality , Food -- Sensory evaluation , Fatty acids , Moringa , Meat -- Quality
  • Description: The objective of the study was to determine growth performance, physico-chemical attributes, oxidative stability and sensory quality of pork from pigs fed one of three dietary treatments, eac containing 0%, 2.5% or 5% (T1, T2 and T3, respectively) Moringa oleifera leaf meal (MOLM). Dietary treatments were formulated to be isonitrogenous and isoenergetic for weaner (6 – 8 weeks) and grower (9 – 13 weeks) phases. Twelve Large White (LW) and 12 Kolbroek (KB) male pigs at 6 weeks of age, initially weighing an average 10 kg, were randomly allocated to one of the dietary treatments, each with four replicates, in individual pens. Feed and water were offered ad libitum. The Longissimus thoracis et lumborum (LTL) muscle of each carcass (n = 24) was sampled for meat quality and fatty acid analyses. Breed differences in measured parameters were observed. In pigs receiving 5% MOLM, the LW had significantly the highest ADFI (P<0.05) than KB pigs. In pigs receiving 2.5% and 5% MOLM, backfat thickness was significantly highest (P<0.05) compared to those receiving 0% MOML. Dietary inclusion of MOLM had no significant effects (P>0.05) on the physico-chemical quality of pork from LW pigs; although it significantly (P<0.05) increased a* and reduced WBSF values in pork from KB pigs. Pork from LW pigs receiving 5% MOLM had significantly increased (P<0.05) n-3 content of the subcutaneous tissue of LW pigs compared to KB, and also when compread to other treatment groups. In both breeds, the composition of PUFA: SFA and n-6: n-3 in the subcutaneous adipose tissue was significantly (P<0.05) lower in T2 and T3 than in T1. The n-3 levels for pork muscle from LW pigs receiving 2.5% and 5% MOLM, and from KB pigs receiving 5% MOLM, were significantly (P<0.05) lower. Inclusions of MOLM significantly (P<0.05) reduced the n-6: n-3 fatty acids in pork from both LW pigs and KB pigs. Consumer scores on sensory attributes (aroma intensity, initial impression of juiciness, first bite, sustained impression of juiciness, muscle fibre and overall tenderness and overall flavor intensity) significantly (P<0.05) increased as the level of MOLM inclusion in the diet increased; and higher scores were observed in fried meat than in boiled for most sensory attributes. It may be concluded that inclusion of MOLM in pig diets up to 5% improved the ADFI, a*, tenderness of pork without adversely affecting the FCR and other physico-chemical quality attributes; and resulted in desired increase in levels of n-3 and reduced the n-6: n-3 fatty acid ratio.
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  • Date Issued: 2014

Perceptions of rural consumers on behaviour and beef quality of cattle slaughtered for traditional ceremonies in the Eastern Cape of South Africa

  • Authors: Soga, Sizwe William
  • Date: 2014
  • Subjects: Meat -- Quality , Consumers' preferences , Consumers -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc Agric (Animal Science)
  • Identifier: vital:11833 , http://hdl.handle.net/10353/d1019812 , Meat -- Quality , Consumers' preferences , Consumers -- South Africa -- Eastern Cape
  • Description: The objective of the study was to determine perceptions of the consumers on how they judged behaviour and beef quality of cattle slaughtered for traditional ceremonies in the Eastern Cape Province of South Africa. A survey was conducted where a sample of 200 consumers were randomly selected and interviewed. Fifty non-descript cattle were slaughtered during traditional ceremonies and two hundred and twenty four (224) cattle were slaughtered at 3 through-put abattoirs (high, medium and low). Meat quality attributes were determined from the cattle slaughtered for traditional ceremonies and from cattle slaughtered at the abattoirs. Data for questionnaires was summarized as frequencies for each ceremony and statistical differences were analysed using chi square test (X2). The effect of Age, breed and sex on beef pH, colour, meat tenderness, temperature and cooking loss of cattle slaughtered during traditional ceremonies, at low, medium and high throughput abattoirs were analyzed using General Linear Model (PROG GLM) of SAS (2003). There was a significant age effect (P < 0.05) on beef tenderness and cooking loss of cattle slaughtered for traditional ceremonies. Age of cattle that have milk teeth to 1 year and age of 6 years to 8 years had an effect on the beef tenderness (25.55 ± 8.05) and cooking loss (48.00 ± 4.26) of cattle slaughtered for traditional ceremonies in Table 4.1. There was no significant sex effect on beef tenderness and cooking loss of cattle slaughtered for traditional ceremonies. Non-descript and Angus cattle slaughtered at low throughput abattoir had an effect on the colour of the beef in Table 4.2. The lightness (27.49 ± 2.53) and yellowness (21.16 ± 0.79) of the beef shows that there was a significant breed effect on cattle that are slaughtered at Low throughput abattoir, however redness of the meat was not affected by breed after slaughter. Cattle that are slaughtered at high throughput abattoir between ages of 6 to 8 years and also cattle that are more than 8 years in Table 4.4 had an effect on cooking loss (p < 0.05). Age between 6 to 8 years had an effect on the beef tenderness from cattle that are slaughtered at medium throughput abattoir. It was concluded that the meat tenderness of the young cattle with milk teeth slaughtered for traditional ceremonies was affected. On the other hand the meat tenderness and cooking loss of beef from the cattle slaughtered from low, medium and high throughput abattoir were affected by sex and breed mostly.
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  • Date Issued: 2014

Effect of dietary inclusion of Moringa oleifera Lam leaf meal on feed conversion efficiency, meat quality, fatty acid composition, shelf life and consumer health-related perceptions of pork

  • Authors: Mukumbo, Felicitas Esnart
  • Date: 2013
  • Subjects: Moringa oleifera , Meat -- Quality , Feed utilization efficiency
  • Language: English
  • Type: Thesis , Masters , MSc Agric (Animal Science)
  • Identifier: vital:11827 , http://hdl.handle.net/10353/d1016071 , Moringa oleifera , Meat -- Quality , Feed utilization efficiency
  • Description: The objective of the study was to determine the feed conversion efficiency (FCE), carcass characteristics, physico-chemical quality, fatty acid (FA) composition and shelf life of pork from pigs fed diets containing either 0% (T1), 2.5% (T2), 5% (T3) or 7.5% (T4) Moringa oleifera leaf meal (MOLM). Consumer health-related perceptions on pork and fatty acids were also investigated. Twenty four crossbred Large White x Landrace pigs of both sexes at 18 weeks of age and initially weighing 71.6 kg on average were housed individually and had ad libitum access to one of the four dietary treatments for a period of six weeks. Average daily feed intake (ADFI) and average daily gain (ADG) and feed conversion ratios (FCR) were calculated as an indication of FCE and pigs were slaughtered at an average live weight of 99.6 kg. Carcass traits such as back fat thickness (BFT), carcass temperatures and pH readings taken 45 minutes and 24 hours (pH45 and pHu) post mortem were recorded. M. longissimus thoracis et lumborum (LTL) samples were taken from each carcass for the determination of lightness (L*), redness (a*), yellowness (b*), thawing loss percentage (TL%), cooking loss percentage (CL%), Warner Bratzler Shear Force (WBSF), shelf life and FA composition. Furthermore a survey was conducted amongst 80 University of Fort Hare Students to determine their health-related perceptions on pork and fatty acids as well as their pork consumption frequency using questionnaires. The FCE of pigs fed on 0-5% MOLM (T1, T2 and T3) diets did not differ significantly, but the FCE of pigs fed 7.5% MOLM (T4) was significantly (p<0.05) reduced. No significant relationship was reported between inclusion of MOLM carcass characteristics and physico-chemical pork quality. There was however a significant improvement (p<0.05) in the shelf life of the pork from MOLM fed pigs in terms of colour and odour during 10 days of refrigerated storage (at 3±1°C). There was a significant (p<0.05) reduction in the total intramuscular fat (IMF) content and the saturated fatty acid (SFA) C18:0 (stearic acid) content and an overall non-significant (p>0.05) increase in the poly unsaturated fatty acid (PUFA) content of pork from MOLM fed pigs. The possible reason for this is that the feeding of MOLM was commenced when the pigs were at an advanced age and weight. The survey revealed that the majority of interviewed students consume fresh (39.7%) and processed (32.4%) pork two to three times a week, perceive pork to be generally healthy (70%) and the second most healthy meat type (39.5%). While the majority (55.4%) were aware of the health implications of FAs they did not know which FA classes pose more of a health risk (51.3%). In conclusion2.5% and 5% of MOLM in finisher pig feed did not negatively affect FCE, carcass characteristics or physico-chemical meat quality; significantly improved pork shelf life and reduced total IMF and SFA content of pork but 7.5% MOLM negatively affected FCE; and the majority of students perceive pork to be the second most healthy type of meat and are generally aware of the health implications of FAs.
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  • Date Issued: 2013

Perceptions on ante-mortem welfare, quantitation of pain and pregnancy biomarkers, muscular fibre architecture and quality of Dohne Merino offal

  • Authors: Fayemi, Peter Olutope
  • Date: 2013
  • Subjects: Merino sheep , Slaughtering and slaughter-houses -- By-products , Biochemical markers , Meat -- Quality , Consumers' preferences , Cooking (Variety meats) , Livestock -- Transportation
  • Language: English
  • Type: Thesis , Doctoral , PhD (Animal Science)
  • Identifier: vital:11824 , http://hdl.handle.net/10353/d1007573 , Merino sheep , Slaughtering and slaughter-houses -- By-products , Biochemical markers , Meat -- Quality , Consumers' preferences , Cooking (Variety meats) , Livestock -- Transportation
  • Description: Sheep farming is practiced extensively in South Africa for its significant contributions to the livestock, wool and meat industries. The sheep farming sector in the country has approximately 13,800 farmers with commercial and communal sheep farmers making up 58 percent and 42 percent of the entire work force (Directorate of Agricultural Information Services, 2008). An estimate of 28.8 million sheep and flock size ranging between ≤ 50 and ≥ 1800 exist in various South African provinces. Although the national herd size is unevenly distributed provincially most of the herds are found in the Eastern Cape (30 percent) followed by the Northern Cape (25 percent), Free State (20 percent) and the Western Cape (11 percent) respectively (Agriculture, Forestry and Fisheries, 2011). Over twenty indigenous and locally developed sheep breeds are managed where about 69 percent of the land area is available for their grazing nation-wide (Campher et al., 1998; Palmer and Ainslie, 2006). Common among the indigenous breeds are the Afrikaner, Blackhead Persian, Blackhead Speckled Persian, Blinkhaar Ronderib, Damara, Karakul, Namaqua Afrikaner, Pedi, Redhead Persian, Redhead Speckled, Swazi and Zulu. The locally developed breeds include Dorper, Van Rooy and Merinos. The local breeds developed from Merinos consist of the Afrino, Dormer, Dohne Merino and South African mutton Merino (Hammond, 2000; Pranisha, 2004; Hinton, 2006; Sorma et al., 2012). All these sheep breeds are best suited for providing by-products such as wool, meat, hide, milk or a combination of products (Dave and Meadowcroft, 1996; Jensen, 2009). The indigenous and locally developed sheep were bred to meet the growing demand for its by-products (Peters et al., 2010). Expectedly, sheep farmers therefore, make use of the products from these sheep as a means of livelihood and sustenance of a viable local society (Cloete and Olivier, 2010).
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  • Date Issued: 2013

Avoidance-related behaviour, bleeding times and the quality of meat from sheep slaughtered at a commercial and a municipal abattoir

  • Authors: Njisane, Yonela Zifikile
  • Date: 2012
  • Subjects: Mutton -- Quality , Sheep -- Quality , Slaughtering and slaughter-houses -- South Africa , Animal behavior , Dorper sheep , Meat -- Quality , Sheep -- Carcasses -- Handling
  • Language: English
  • Type: Thesis , Masters , MSc Agric (Animal Science)
  • Identifier: vital:11818 , http://hdl.handle.net/10353/d1004195 , Mutton -- Quality , Sheep -- Quality , Slaughtering and slaughter-houses -- South Africa , Animal behavior , Dorper sheep , Meat -- Quality , Sheep -- Carcasses -- Handling
  • Description: The objective of the study was to determine the avoidance-related behaviour, bleeding times and the quality of meat from sheep of different gender, breed (Dorper, Merino, and their crosses) and age groups, slaughtered at a commercial and municipal abattoir. Castrates and ewes of different age groups (1= <10months, 2= 11-12months, and 3= >12months) and breeds were used. From the commercial abattoir, 90 castrates and 110 ewes were used, while 66 castrates and 19 ewes were obtained from the municipal abattoir. Meat samples were obtained to determine meat colour, ultimate pH, temperature, cooking loss and tenderness. Correlations between bleeding times and meat quality variables were also determined. The two abattoirs differed in terms of technology and the procedures used, and this brought about different response behaviours in sheep at slaughter, bleeding times at exsanguination and the quality of meat produced. Animal-related factors (breed, gender and age classes) had no effect on the avoidance-related behaviour of sheep slaughtered at the commercial abattoir, while these factors affected those sheep slaughtered at the municipal abattoir. These factors also had an effect on the quality of meat produced at both abattoirs. Gender and weight of the animals had effects on the bleeding times at exsanguination at both abattoirs. Bleeding times did no correlate with any of the meat quality variables, but correlations among meat quality variables were observed. Avoidance-related behaviour, bleeding times, and the quality of mutton from sheep slaughtered at a commercial and a municipal abattoir was affected by breed, age, and gender.
  • Full Text:
  • Date Issued: 2012

Effects of feeding Moringa Oleifera leaf meal as an additive on growth performance of chicken, physico-chemical shelf-life indicators, fatty acid profiles and lipid oxidation of broiler meat

  • Authors: Wapi, Cwayita
  • Date: 2012
  • Subjects: Moringa , Broilers (Chickens) , Meat -- Quality
  • Language: English
  • Type: Thesis , Masters , MSc Agric (Animal Science)
  • Identifier: vital:11822 , http://hdl.handle.net/10353/d1007546 , Moringa , Broilers (Chickens) , Meat -- Quality
  • Description: Effects of feeding Moringa oleifera leaf meal as an additive on growth performance of chicken, physico- chemical shelf-life indicators, fatty acids profiles and lipid oxidation of broiler meat The main objective of the study was to determine the effect of M.oleifera leaf meal (MOLM) as an additive on growth performance, carcass characteristics, physico-chemical shelf-life indicators (colour, ultimate pH, driploss), fatty acids profiles and lipid oxidation of meat from broilers. A total of 432 1day old unsexed broiler chicks (Aviane 48) were randomly allocated to four dietary treatments (TRTS) in 72 cages. There were 18 cages per treatment and each cage allocated 6 chicks. Water and feed was provided at ad libitum. The feeding phases were, prestarter (0-7 Days), starter (8-18 Days), grower (19-28 Days), finisher (29-35 Days). The four TRTS contained graded levels of MOLM at 1000g/ton, 750g/ton, 500g/ton, and 0g/ton (control), respectively. The birds were slaughtered at 35 days of age. Breast muscles were sampled for meat, ultimate pH (pHu ), colour, drip loss over a 7 days shelf-life test. After each day’s test sub-samples were dipped in liquid nitrogen and kept at -180 C for thiobarbituric acid reactive substances determination. On Day1 and Day 7 extra sub-samples were also kept at -180 C for fatty acids analysis.The TRTS had no effect on average feed intake (AFI), feed conversion efficiency (FCE), and on average daily gain (ADG). Slaughter weight (SW), carcass weight (CW), dressing percentage and gizzard weight (GW) values were similar in all TRTS. Liver weight (LW), heart weight (HW), and gastro-intestinal fat (GIF) differed in all the TRTS, with treatment 2 having the highest value of HW (28.3±2.55), and LW (44.2±1.60) was the highest on treatment 4 . The pH values in all TRTS were constant from Day1 to Day5, reached peak on Day6, and then declined on Day7. Meat from broilers given treatment 1 with MOLM (1000g/ton) had the highest lightness (L*) values. The redness (a*) values were the highest in meat from treatment 2 (750g/ton MOLM). Treatments had no effect on yellowness (b*) values and on drip loss of the breasts. During storage L* values were high from Day1 to Day5 and decreased from Day6 to Day7. Drip loss increased with storage time as expected. Treatment 4 (control) had the highest proportions of poly-unsaturated fatty acids (PUFA) (30.3±1.87). Treatment 1 (1000g/ton) had the highest proportion of saturated fatty acids (SFA) (60.9±1.87). Treatment 1 (1000g/ton) had the highest proportion of SFA (60.9±4.30). Treatment 2 (750g/ton) had the highest n-6/n-3 ratio than other TRTS. Days had no effect (P>0.05) on PUFA, SFA, and n-6/n-3 ratio. Treatment 1 had a highest amount of malondialdehyde (MDA), treatment 4 had no effect (P>0.05) on MDA . Storage time had an effect (P<0.05) on MDA levels, except for on Day1 and Day7. Day2 had the highest amount of MDA (0.7±0.08). The use of MOLM as an additive in broiler diets reduced lipid oxidation in meat, and maintained the quality of the broiler meat during storage. It also did not have any adverse effects on the growth performance of broilers. Therefore, it has the potential to be used as an additive in broiler diets.
  • Full Text:
  • Date Issued: 2012

Perceptions of rural consumers and the quality of mutton at purchase points in the Eastern Cape Province, South Africa

  • Authors: Rani, Zikhona Theodora
  • Date: 2012
  • Subjects: Meat -- Quality , Mutton -- Quality , Consumers' preferences , Quality of products , Consumers -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc Agric (Animal Science)
  • Identifier: vital:11823 , http://hdl.handle.net/10353/d1007562 , Meat -- Quality , Mutton -- Quality , Consumers' preferences , Quality of products , Consumers -- South Africa -- Eastern Cape
  • Description: The objective of the study was to determine perceptions of rural consumers on mutton quality, and the quality of mutton at purchase points in the Eastern Cape Province, South Africa. The study was conducted in five different municipalities (Buffalo City, Nkonkobe, Ngqushwa, Lukhanje and Amahlathi). A survey was conducted where a sample of 215 consumers were randomly selected and interviewed, either at point of purchase or as they left the shops. The survey was not limited to the shoppers only but also extended to households from the villages. Questions on some of the most important meat quality cues were compiled. The physico-chemical quality of mutton purchased from different shops was also determined. Forty different shops and butcheries selling mutton from all the selected municipalities were visited. Different parts of mutton samples were bought. Physico-chemical qualities of mutton such as colour (L* - lightness, b* - redness and a* - yellowness) and meat pH measurements were taken at points of purchase. Cooking loss and tenderness evaluations were later done at the Meat Science laboratory at the University of Fort Hare. The results indicated that price was one of the major factors affecting the purchasing decisions of consumers. Thirty four percent of the consumers preferred mutton as compared to other protein sources, even though they were not buying this type of meat because it was not affordable to them. Both male and female consumers suggested that more sheep farmers need to be established in order to reduce the levels of imported mutton into South Africa. They also highlighted that selection programmes that will result in efficient sheep production and reduced mutton prices need to be implemented. Meat at points of purchase was affected by season resulting in lower lightness (L*24.7±0.49) values in winter and higher (L* 32.2±0.49) in Spring. The class of shop did not have an effect on meat quality attributes. Trotter had high values of lightness (L*30.4±2.78a), redness (a*30.4±2.78a), yellowness (13.1±1.08a), pH (6.3±0.12a), tenderness (24.9±3.69b) and cooking loss (39.5±4.38ab). The number of days from when the meat was put on the shelves to the time when it was purchased for consumption (days to purchase) had a significant (P<0.05) negative correlation with the Warner Braztler Shear Force (WBSF)values and lightness of the meat. Significant negative (P < 0.05) correlations between pH and colour of the meat (L*, a* and b*) were also observed. It was concluded that rural consumers perceive the quality of mutton as the best and that the physico-chemical quality of meat purchased from different shops was different, largely based on the part of meat, meat storage conditions and not necessarily on the class of the shop.
  • Full Text:
  • Date Issued: 2012

Antioxidant activity and the quality of meat from goats and broilers supplemented with Moringa (Moringa Oleifera) leaves

  • Authors: Qwele, Kumnandi
  • Date: 2011
  • Subjects: Goats -- South Africa -- Eastern Cape , Chickens -- South Africa -- Eastern Cape , Meat -- Quality , Moringa
  • Language: English
  • Type: Thesis , Masters , MSc Agric (Animal Science)
  • Identifier: vital:11803 , http://hdl.handle.net/10353/469 , Goats -- South Africa -- Eastern Cape , Chickens -- South Africa -- Eastern Cape , Meat -- Quality , Moringa
  • Description: The objective of the study was to determine the antioxidant activity (AA) and the quality of meat from goats and chickens supplemented with Moringa (Moringa oleifera) leaves. For the first experimental chapter, eighteen 9 months old Xhosa lop-eared, castrated goats with an average body weight of 14 kg were used. There were three supplements namely, Moringa oleifera leaves, sunflower cake and grass hay. There were six goats per supplement. The goats were slaughtered after 60 days of supplementation and the Muscularis longissimus thoracis et lumborum (LTL) of the right side of each goat was used to determine fatty acid composition, total phenolic content (TPC), diphenylpicrylhydrazyl (DPPH) assay, 2, 2 azino-bis (3- ethylbenzothiazoline-6-sulphonic diammonium salt (ABTS) assay and reducing power assay of meat. Glutathione (GSH), catalase (CAT) and superoxide dismutase (SOD) and lipid peroxidation (thiobarbituric acid reactive substances, TBARS) were taken as parameters to evaluate in vivo AA of the meat. For the second experiment, twelve male broilers were used in four groups of dietary supplementation. Three broilers were allocated per group. After slaughter, the breast muscle was sampled for total phenols, flavonoids, proanthocyanidins, TPC, ABTS, GSH, CAT, SOD, lipid peroxidation, ultimate pH (pH24), colour (L* (lightness), a* (redness), b* (yellowness)), WB-shear force and cooking loss. In both chapters Moringa leaves exhibited the highest AA. Meat from goats supplement with Moringa exhibited the highest AA. Meat from broilers supplemented with a mixture of Moringa leaves, broiler finisher and crushed maize, had the highest (P < 0.05) pH24 and L* values. Moringa can therefore be used to preserve meat without changing the quality of meat.
  • Full Text:
  • Date Issued: 2011
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