Theses and Dissertations

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Alternative remedies used by resource-limited farmers in the treatment and manipulation of the reproductive system of non-descript goats in the Eastern Cape province, South Africa
(University of Fort Hare, 2014) Rwodzi, Maxwell
This study was carried out to determine alternative approaches used by resource-limited farmers to enhance fertility and in the treatment of reproduction ailments of goats in Mount Frere area, Eastern Cape Province of South Africa. Furthermore, information on farmer perceptions pertaining to these practices was also gathered. A questionnaire survey was conducted to determine materials used by resource-limited farmers to enhance fertility and treat reproductive ailments. The survey revealed 10 plant species that were commonly used for reproductive health in goats. Elephantorrhizza elephantina (37.1%) and Rhoicissus tomentosa (25.7%) were the most frequently cited plant species. Elephantorrhiza elephantina and R. tomentosa recorded the highest Fidelity Level (FL) values of 92.86% and 75% respectively, for their use in the treatment of reproductive ailments and these were the plants on which further studies were conducted. The study also revealed that farmers had different perceptions on the effectiveness of the traditional medicines. An in-vivo assessment was done to determine efficacy of E. elephantina and R.tomentosa using serum estradiol and progesterone profiles. The highest (P<0.05) serum estradiol and progesterone concentration was observed in animals administered with aqueous extracts of E. elephantina and R. tomentosa mixture while the least (P<0.05) concentrations were observed in the negative control group. Does administered with a mixture of aqueous E. elephantina and R. tomentosa extract had the highest (P<0.05) body weight (65 kg) as well as body condition scores, while the negative control which were administered with distilled water had the least body weights (54 kg) and body condition scores. Does that were administered with a mixture of E.elephantina and R. tomentosa were all pregnant with twins (100%), confirmed by a doppler ultrasound scan.
Characterisation of the production and consumption of milk In the communal livestock production sector of the eastern Cape Province, South Africa
(University of Fort Hare, 2016) Kumbirai, Kaguru Tinashe
The study was conducted in Eastern Cape Province, South Africa with the objective of characterising milk production and consumption among the communal households. A pretested semi-structured questionnaire was used to collect data through a single visit survey between June 2014 and May 2015. The study was undertaken in five randomly selected communal districts using a multi – stage area probability sampling method. Household sample size was calculated using a statistical methodology through a fixed formula based on a rural population size of 4410000, at a confidence level of 95%. A total of 500 households were selected with a sample size of 20 households in 5 communities within five different communal districts within the province.Half of the total sample size was used to represent the number of non-milk producing households (250) to get a true reflection on consumption profiles for nonproducers. Across the province the average communal family size was between 5-10 members with a monthly income of ZAR1340 per household. On average, pasture land size of the sampled households was 1 ha, with a range of 0.25-1.7 ha. The numbers of animals per species found in the studied province was highest for sheep (310) followed by cattle (227) and goat (87). Average livestock holding per household in the study area was 9.85 TLU (Tropical Livestock Unit). According to the respondents the predominant milking livestock numbers were between 1-3 animals milking per household. In the studied area traditional hand milking of livestock was the major milking practices at 12% in goats, 15% in sheep and 45% in cattle milk production. Consumption was the predominant reason for milk production recorded at 27% across the province. Milk production was 43% most preferred in cattle followed by 32% in goat and least at 29% in sheep across the province. In general from the study it was noted that the majority (38%) of the respondents across the province indicated 0-5mins as the time it took to milk most milk producing livestock. The majority of the milking practices was done (37%) predominantly once a day, followed by 2% twice daily across the province. The daily milk production was on average (0.45±1.07) 2-5 litre in cattle, (4.86±0.814) 0-1litre in goats and (2.62±0.42) 0-1 litre sheep per producing house hold with in the province The monthly raw milk consumption in the province was (2.20± 1.42) 2-5 litres of cattle milk, (4.78±0.79) 2-5 litres of goat milk and (4.98±0.69) 2-5 litres of sheep milk per consuming household. Pasteurised milk was found to be the most regularly consumed and preferred milk product at 4.78±0.84 litres per consuming household each month across the province. Other monthly provincial cattle milk products consumed were 0.5 kg-1 kg of powdered milk and 2- 5 litres of sour milk. Household composition and consumer preference were significantly (P˂0.05) the primary reasons for the consumption of milk and milk products. The standard price ranges for milk and milk products were R8.50-R9.50 per litre of fresh milk, R7.50-R8.50 per litre of sour milk, R33.00-R35 per kg of powdered milk and R11.50-R12.50 per litre of pasteurised milk. In general, training of selected few household heads as extension staff and para vet practices is of paramount importance so as to improve animal health together with milk production techniques. In conclusion, there was low milk production and consumption of milk and milk products in the communal households and livestock sector. The results from the study conclude there was no difference in milk production but a difference in the consumption of milk and milk products across the communal livestock production of the Eastern Cape Province, South Africa.
Characterization of village chicken health and management practices in the Amatola Basin of the Eastern Cape Province, South Africa.
(University of Fort Hare, 2011) Nyoni, Njongenhle Mhlanhlandlela Bernard
The majority of rural households in South Africa own village chickens which contribute significantly to their livelihoods. However, limited research has been conducted to characterize, understand and develop village chicken production in South Africa. This hinders the designing and implementation of village chicken-based developmental programmes that will benefit farmers in rural areas. Thus, it is imperative to initiate studies to describe village chicken production. This study was conducted to characterize village chicken production in Amatola Basin of the Eastern Cape Province of South Africa. Baseline information was gathered using a questionnaire survey of 81 identified from 7 out of 13 villages using snowball sampling technique. Consequently, 20 households were selected to participate in a monitoring study (from July 2010 to June 2011) through purposive sampling. Most (60%) chicken flocks were owned by women and mainly raised to meet household food requirements. Some (28.4%) farmers occasionally sold cocks and hens to neighbours, at an average price of R50 (USD7.55) per bird, as a way of culling their flocks and generating income. However, village chickens were mainly kept for food security rather than for their terminal benefit of cash. Although, all chicken flocks were produced under the scavenging feeding system, most (96%) flocks were provided with supplementary feed and drinking water. A majority (93.8%) of households also provided some form of shelter for their chickens. The mean cock to hen to chick ratio was 1:5:15. On average, each household owned 17 (±2 S.E.M.) chickens, and hens had 3.3 clutches per annum. Chicks hatched and chickens received as gifts represented the flock entries, while exits included mortality, consumption, sales and gifts or donations, in that order. Generally, both exits and entries were more pronounced in the summer season than in other seasons. Most (81.5%) farmers experienced chicken losses due to predation and health related problems. Parasitism ranked high amongst the village chicken health challenges. During monitoring, the endoprasites identified included nematodes, cestodes and protozoa. Coccidia were the most prevalent endoparasites. The chickens were also infested with a variety of ectoparasites namely: mites, lice, fleas and ticks. The sticktight flea Echidnophaga gallinacean was the most prevalent species. Although ectoparasite infestations were most pronounced in summer, almost all chickens harbored one or more of these parasites throughout the study period. The prevalence and intensity of parasite infestations were significantly (P<0.05) higher in the summer season compared to the other seasons. This was followed by the autumn, spring and winter seasons, respectively. The majority (77.5%) of farmers resorted to alternative remedies, mostly medicinal plants, for treating diseases and controlling parasites. Medicinal plants were used because they were locally available, cheap and perceived to be effective. Therefore, village chicken production in the rural Eastern Cape Province is characterised by several challenges which counter the significant role chickens play in the livelihood of rural households.
Effect of pre-slaughter stress of pigs on the levels of cortisol, creatine kinase and their subsequent relationship with pork quality
(2014) Nzolo, Jama
The study was conducted to determine the effect of pre-slaughter stress of pigs on the levels of cortisol, creatine kinase (CK) and their subsequent relationship with pork quality. From our knowledge, there is paucity of information on transportation, lairage duration and sex effects on saliva cortisol and its relation with serum cortisol, urine cortisol and other meat quality traits. Stage one of the study assessed the effect of sex and time to slaughter (transport and lairage duration) on the levels of cortisol and CK in crossbred pigs. The second stage of the study evaluated the effect of sex and lairage duration on pork quality. The trials comprised of 60 22-weeks old commercial crossbred pigs [(30 boars vs. 30 gilts) with an average body weight of 76.9kg for gilts and 78.3kg for boars. Thirty pigs (15 Boars vs. 15 Gilts) were slaughtered on arrival after a 120km road journey and the other 30, after travelling the same road and distance, were slaughtered after having been in the lairage for 20 hours. Saliva samples were obtained during three time periods: between 07:00-10:00 on the day before the journey, on arrival at the abattoir and after lairage. Levels of cortisol in serum and urine and CK in serum samples collected at slaughter were determined. The samples (saliva and serum) were centrifuged at 20oC for 10 min at 3550 x g and stored at -20oC in separate vials until analysis. Pork quality was assessed using muscle pH, colour, thawing and cooking losses and Warner-Bratzler Shear Force. Correlations between cortisol levels in saliva, serum and urine and meat quality were assessed. The effect of sex and time to slaughter on saliva cortisol was significant. Statistical analysis showed significant interaction of sex by time to slaughter on serum cortisol. It was only the effect of sex that demonstrated higher (P <0.05) serum creatine kinase levels in gilts. Likewise, urine cortisol was influenced (P <0.05) only by time to slaughter. Saliva cortisol after transportation (r = 0.52) was correlated (P <0.05) with urine cortisol. The study suggests that there are greater responses of the Hypothalamic-pituitary-adrenal axis following time to slaughter (transport and lairage duration) between gilts and boars. This can be used in measuring cortisol in saliva, serum and urine, and serum creatine kinase to determine stress levels in pigs. Besides the lightness (L*) colour value which was significantly lower (P <0.05) in meat from gilts than from boars, the results of this study showed no interaction or individual effect (sex or lairage duration) on pH and other colour measurements. Meat cooking loss was affected (P <0.05) by gender x lairage interaction. Effect of lairage duration (as an individual effect) on the measured meat quality traits was not significant (P <0.05). Correlation analysis showed significant (P <0.05) negative relation between baseline saliva cortisol (r = -0.40) and the pork L* value. Saliva cortisol after lairage duration (r = -0.38 and r = 0.38) was correlated (P <0.05) with pH45 and pork a* value, respectively. Serum cortisol (r = -0.35) was negatively correlated (P <0.05) with pH45. Moreover, there were negative correlations (P <0.05) between saliva cortisol after transportation (r = -0.35), saliva cortisol after lairage duration (r = -0.44), serum cortisol (r = -0.40) and meat cooking loss. The study suggests that cortisol in saliva and serum can be used to determine effect of time to slaughter (transport and lairage duration) on meat quality traits from gilts and boars.
Effect of Tenebrio molitor larvae as a protein source on growth performance, carcass yield and meat quality of broiler chickens.
(University of Fort Hare, 2016) Mngqi, Sinethemba Census; Muchenje, V.
This study was conducted to assess the effect of including Tenebrio molitor larvae (T. molitor L) as a protein source in different diets on broiler performance, carcass characteristics and meat quality. A total of 144 day-old Cobb-500 chicks were randomly allocated into three treatment groups, each was allocated 16 birds and reared in 9 identical pens. Experimental diets used were as follows: T1 Control (no T. molitor L inclusion); T2 and T3 contained levels of T. molitor L at 5% and 10% of dry matter (DM) intake, respectively. Body weights (BW), average daily gain (ADG), feed intake (FI), and Feed conversion ratio (FCR) were measured for the 1st experimental chapter. For the second experimental chapter; live weights (LW) of broilers were recorded before slaughter and thereafter carcass weights (CW), meat yield (weights of breast, thigh, drumstick and wing) were recorded. The dressing percentage (DP %) was also calculated. Breast muscles were sampled for meat pH and colour measurements. The LW of birds from T1 (0% T. molitor L) were significantly different (P<0.05) from both T2 (5% T. molitor L) and T3 (10% T. molitor L) which were similar to each other, with T2 exhibiting the highest live weights (2166g) and the control treatment exhibiting the lowest live weights (2018.3g). In CW, T1 was significantly different (P<0.05) from T2 while it was similar (P>0.05) to T3. The dressing % of T1 was significantly different (P<0.05) from T2 and T3 which were similar to each other, with T2 having the highest dressing percentage (78, 2%) and T1 having the lowest DP% (66%). The breasts in T2 were significantly higher and different (P<0.05) from both T1 and T3 which were similar to each other. The drumsticks in T3 were significantly different (P<0.05) from T1 while they were similar to T2 with values with T2 having highest values. After 45 minutes of slaughter, a significant difference (P<0.05) was observed in L⃰ among all treatments. In redness (a⃰), T3 was significantly different from T1 but was similar to T2 and all treatments in this study exhibited a darker red meat, with T3 muscles exhibiting darker red colour than the other treatments. Similar results were observed in yellowness (b⃰), where the breast muscles from T3 were more yellow than the other treatments. After 24 hours of slaughter, T2 L⃰ values were significantly different (P<0.05) from both T1 and T3 which were similar to each other. It was also found that the broiler chickens given diet with no T. molitor L inclusion (T1) had lower values of BW, FI, ADG and FCR throughout the experiment than those that were in T2 and T3 with 5% and 10 % T. molitor L inclusion levels, respectively. However, it was also found that although broilers with 5% T. molitor L inclusion (T2) in their diet had high ABW and ADG than the broilers with 10% T. molitor L inclusion (T3), the T3 birds compared favourably to T2 birds as they required low feed intake to reach the same slaughter weight due to high FCR. It was, therefore, concluded that T. molitor L meal can be incorporated into the diets of broilers to produce heavy birds either at 5 or 10%. However, although 5% T. molitor L inclusion yields heavier carcasses, the 10% T. molitor L inclusion compared favourably to 5% inclusion since it required low feed intake to reach the same slaughter weights and there were slight differences on meat quality attributes between the two treatments.Thus T. molitor L at 10% inclusion levels was the best inclusion level to enhance broiler growth performance, carcass yield, meat yield and meat quality.
Effects of dietary supplementation on physico-chemical and consumer sensory characteristics of chevon from South African indigenous goat genotypes
(University of Fort Hare, 2010) Xazela, Nomasonto Martha
The study was conducted at the University of Fort Hare farm to assess the effect of dietary supplementation on physico-chemical and consumer sensory characteristics of chevon from South African indigenous goat genotypes. Forty-eight 6-month-old Xhosa lop-eared (XLE), Nguni (NGN), Xhosa-Boer cross (XBC) and Boer (BOR) castrated goats with a body weight range from 20 to 25 kg were used in this study. Half of the goats in each genotype were supplemented with 200g/head/day of sunflower cake. The other half of goats in each genotype was not supplemented. The goats were slaughtered at day 90 to determine slaughter weight (SLW), cold dress mass (CDM), meat colour, cooking loss, meat pH and Warner-Bratzler (WB) shear force values. Furthermore, a consumer sensory evaluation of cooked or fried chevon from supplemented and non-supplemented goats was conducted with consumers of different ages, tribes and gender. The XLE and NGN goats had higher pH24 (P < 0.05) than BOR and XBC goats. Supplemented BOR goats had higher L* values than their non-supplemented counterparts (P < 0.05). The other meat quality attributes in XLE and NGN were comparable to those in meat from the Boer goat. Female respondents gave higher (P < 0.05) sensory scores than male respondents for both cooked and fried meat on aroma intensity. Shona consumers gave higher (P < 0.05) aroma intensity scores than the Xhosa and the Zulu consumers for both cooked and fried meat. In the non-supplemented goats, fried meat for all genotypes was superior (P < 0.05) to the cooked meat for initial impression of juiciness. Age and gender of respondents and thermal treatment influenced initial impression of juiciness scores (P < 0.05). The quality of chevon from XLE and NGN was comparable to that of the Boer goat, and dietary supplementation improved most meat quality attributes. Chevon from the supplemented goats had higher consumer sensory scores than chevon from the non-supplemented goats.
Effects of grazing and housing management systems on greenhouse gas emissions, blood profiles and meat quality of Nguni goats.
(University of Fort Hare, 2016) Chikwanda, Allen Tapiwa; Muchenje,V.
The broad objective of this study was to evaluate the effects of grazing and housing management systems on greenhouse gas emissions, blood profiles and meat quality of Nguni goats. A total of 64 castrated Nguni goats were used and a housing structure was designed to accommodate the goats as well as evaluate effects of type of floor on greenhouse gases, meat quality, blood metabolites and fatty acid profiles. In the first experiment: Forty eight castrated Nguni goats, at 6-7 months old were used for herding (H) or tethering (T) management systems and randomly allocated to pens with earth (E) or slatted (S) floors. Gas sampling was done using static chambers and analysed using a SRI 8610C gas chromatography machine. The highest CH4 fluxes were from the manure of herded goats on earth floors (HE). The highest CO2 fluxes were from manure of herded goats that were housed on slatted floors (HS): The highest N2O fluxes were from the manure of tethered goats that were sheltered on slatted floors (TS). It was concluded from the first experiment that goat manure is an important source of GHG that is influenced by grazing and floor type management systems. The second experiment was done to evaluate greenhouse gas (GHG) emission from disused (DP) vs occupied goat pens (OP) with earth (EF) or slatted (SF) floors. Eight previously occupied pens were used in this study. Sixteen goats were randomly put in the pens labelled occupied pens with earth floors (OPEF) and occupied pens with slatted floors (OPSF) resulting in four goats per OP. There were month by pen use; month by floor type; and use by floor type interaction effects (P < 0.05) on CH4 production. Floor type, use (DP vs OP) and month affected (P < 0.05) CH4 production. Manure on earth floors of occupied pens (OPEF) emitted the highest (P < 0.05) methane followed by earth floors of disused pens (DPEF). The least CH4 was emitted from DPSF. There was pen use (DP vs OP) by floor type interaction effect (P < 0.05) on CO2 emission. Floor type and pen use affected (P < 0.05) CO2 production. Manure in occupied pens with slatted floors (OPSF) produced the highest CO2 and the least CO2 was from disused pens with slatted floors (DPSF). Floor type and month influenced (P < 0.05) N2O production. It was concluded that continued use of goat pens increased GHG emissions. However, disused goat pens with manure remain an important source of GHG as they continued to emit quantifiable levels of CH4, CO2 and N2O. The third experiment was done to determine the effects of grazing and housing management systems on the concentrations of blood metabolites, activity of creatine kinase, body weight (BW), body condition score (BCS) and carcass characteristics using 48 castrated Nguni goats. Tethered goats had higher (P<0.05): urea, creatinine, total protein, globulin concentrations and more activity of CK than herded goats. On the other hand, herded goats had higher (P<0.05) plasma glucose (H: 3.39±0.020 vs T: 3.23±0.020 mmol/L), serum albumin (H: 15.30±0.147 vs T: 14.82±0.144 g/L) concentration. It was concluded that serum concentrations of all the metabolites and the activity of CK were sensitive to grazing system. Herding of goats promoted more glucose concentration and preservation of muscle protein and hence superior body weights and BCS than tethered goats. The fourth experiment was done to determine the effects of grazing and housing management systems on the activity of creatine kinase (CK) and cortisol concentration, and chevon quality. Further, the effect of muscle type [Muscularis longissimus thoracis et. Lumborum (LTL) and triceps brachii (TB)] on chevon quality was also investigated. Forty eight castrated Nguni goats aged 6- 7 months were randomly allocated to tethering (n=24) and herding (n=24) treatments. Floor type affected meat (P<0.05) pH24. Tethered goats had higher (P < 0.05) L* and CL % than herded goats. Muscle type had a significant influence (P < 0.05) on a*, WBSF and pH. It was observed and concluded that T resulted in higher L* and more CL% whilst SF lowered the pH24 of chevon; at the same time meat from the TB muscle was more tender, despite having a higher pH24 and more CL % relative to LTH cuts. The fifth experiment was done to determine the effect of grazing and floor type on fatty acid composition of chevon from tethered and herded Nguni goats. Floor type had no effect on fatty acid composition. Oleic, stearic, palmitic and linoleic were the major fatty acids. Chevon from tethered goats had higher (P < 0.05) proportions of long chain polyunsaturated fatty acids (PUFAs): eicosapentaenoic, docosapentaenoic, docosahexaenoic, conjugated linoleic acid (CLA) and more total SFA, total PUFA, total Omega- 6 and total omega 3 fatty acids than herded goats. On the other hand, chevon from herded goats had more (P < 0.05) C18:1c9, C18:2t9, 12 (n-6), C20:3c11, 14, 17 (n-3) and total MUFA than tethered goats. However, there was no difference (P > 0.05) in the PUFA: SFA and n-6/n-3 fatty acid ratios between the herded and tethered goats. It was concluded that tethering promoted higher proportions of beneficial PUFAs which were more in TB than LTH muscle. The overall conclusions from the whole study were that goat manure is an important source of GHG with high CH4 being emitted from earth floors of herded goats. High CO2 and N2O are emitted from SF of herded and tethered goats, respectively. There were no major differences in meat quality between herded and tethered goats. However, herding promoted more live weight gain than tethering. On the other hand, tethering promoted more beneficial fatty acids. Therefore depending on the objective of the enterprise, smallholder farmers can safely tether or herd their goats. Further, there is need to develop technologies to harness CH4 from goat manure.
Effects of natural antioxidants and thermal treatment on quality of meat from Bonsmara and non-descripts cattle
(University of Fort Hare, 2015) Falowo, Andrew Bamidele
The broad objective of this study was to determine the effects of natural antioxidants and thermal treatment on quality of meat from Bonsmara and non-descript cattle. A survey was conducted among 222 consumers in Alice (Fort Hare University community), Eastern Cape Province to determine the level of their awareness on application of antioxidants as preservatives in meat and meat products during storage. Representative samples of Muscularis longissimuss thoracis et lumborum and liver were collected from each carcass of Bonsmara (n=40) and non-descript (n=40) cattle reared on natural pasture to determine the effect of natural antioxidants and thermal treatment on their quality. The results from the survey revealed that 51.35% of the respondents had not heard about the use of antioxidant as preservatives in meat products. However, among the remaining respondents (48.65%) that were aware of antioxidant and its use as preservative, about 19% knew of natural antioxidants, 35% synthetic antioxidants while 46% had knowledge of both. The results further revealed that the majority of the respondents (82%) that had knowledge of natural antioxidants were concerned about the use of synthetic antioxidants in meat and meat products due to their health consequences. The in vitro antioxidant and antibacterial analyses of Bidens pilosa and Moringa oleifera leaf extracts revealed that they contain rich bioactive compounds. Furthermore, the addition of leaf extracts from Moringa oleifera (ML, 0.05 and 0.1% w/w) and Biden pilosa (BP, 0.05 and 0.1% w/w) to ground raw beef as a natural antioxidant were found to improve the physicochemical, oxidative stability and microbiological qualities of meat compared to the control (meat without extract) and BHT treatment (0.02% w/w) during 6 days storage at 40 C. Cattle breed did not have much effect on colour parameters. However, the overall pH of ground beef treated with extracts showed lower values than control and BHT treated beef. Also, ground beef samples containing extracts exhibited (P < 0.05) better colour stability, especially higher redness (a* values), than the control. The formation of TBARS in beef samples treated with extracts was significantly (P < 0.05) lower than the control and BHT treatment. The antibacterial assay of the extracts revealed an appreciable broad spectrum activity against the tested bacteria and microbial counts in ground beef samples compared to control and BHT group. Ground beef treated with plant extracts exhibited lower microbial and lactic acid bacterial counts (P < 0.05) at day 0 and 3 than control samples. Moreover, it was observed that application of sous vides thermal method did not significantly affect the fatty acids and mineral loss in beef and liver across the treatments. However, the total concentration of MUFA was lower in raw liver (20.11±2.38 - 21.08±1.23%) than in beef (40.22±1.90 - 42.53±1.29%), while total PUFA content were higher in liver (30.73±2.60 - 31.11±1.19 %) than in beef samples (10.13±3.36 - 11.02±2.74%) (p < 0.05). The results also revealed that liver samples from Bonsmara and non-descript cattle had a higher percentage of intramuscular fat content of 4.67 ± 0.53% and 4.44 ± 0.53% respectively, and fat free dry matter of 27.51 ± 1.05% and 25.73 ± 1.05%, respectively, than the beef samples (p < 0.05). The concentrations of Mg (52.80±0.22 - 53.70±0.02mg/100g) and Zn (8.90±0.15 - 19.60±0.15mg/100g) were higher in beef than liver samples. The level of Ca (17.00±0.17 - 17.50 ± 0.17mg/100g) in liver was higher than that of beef samples. It was concluded that most consumers preferred the use of natural antioxidants in meat products than synthetic antioxidants due to their health risk. The effectiveness of M. oleifera and B. pilosa leaf extracts on meat quality also revealed that these plants are promising candidates as natural preservatives and their application should be considered in the meat industry. Lastly, findings from this study showed that application of the sous vide technique could protect meat products from nutritional loss during thermal treatment.
Fatty acid composition, colour stability and lipid oxidation of mince produced from fresh and frozen/thawed fallow deer meat.
(University of Fort Hare, 2016) Chido, Chakanya; Muchenje, V.
The aim of the study was to determine the fatty acid composition, colour stability and lipid oxidation of fresh mince produced from fallow deer and to evaluate the effect of frozen storage duration on the retail display shelf life of the mince. A total of 31 fallow deer carcasses were used in the study. After cooling for 24hrs, the carcasses were deboned, external fat from the fore and hindquarter muscles removed and individually vacuum packed. For the first trial, seven fallow deer carcasses were used. Meat from the hind and fore-quarters of each carcass was divided into two equal batches per animal. One batch was minced (through a 5 mm die) and packed into oxygen permeable overwraps and refrigerated at 4°C for a period of eight days under retail display conditions. The second batch was vacuum packed and frozen at -20°C for 2 months at the end of which mince was also produced and monitored over an eight day period under the same conditions that were used for the fresh mince. Colour, pH, lipid and myoglobin stability was determined. Proximate and fatty acid composition was also determined. No differences (P>0.05) were noted between proximate composition of fresh and frozen/thawed minced meat. The lipid content of fallow deer was 2.4% (±0.04). Total n3 fatty acids differed (P<0.05) between treatments and decreased with increased storage and display day. There were significant (P<0.05) treatment and time interactions on all measured colour parameters, TBARS and myoglobin forms. Fresh mince was lighter and had higher redness (a*) and yellowness (b*) values than mince from two months frozen stored meat. Hue angle for fresh mince remained stable throughout display whereas it increased for frozen/thawed mince. Fresh mince had lower TBARS values than frozen/thawed mince. Minced meat produced from frozen/thawed deer meat had higher surface met-myoglobin and total met-myoglobin percentages. Surface and total oxy-myoglobin percentage was higher in fresh mince. The first trial clearly showed colour and lipid stability differences between fresh mince and mince from frozen/thawed meat. It also showed that fresh mince has a longer retail display life than mince produced from frozen/thawed meat (six days and four days, respectively). In the second trial, the effects of frozen storage duration on colour and lipid stability were investigated. Twenty-four fallow deer were used. Twelve were harvested in June (6male 6female) and the other twelve in August (6 male 6female) of the same year.Twenty four hours after harvesting, the fore and hindquarter muscles of the carcasses were deboned, vacuum packed and kept at -20°C until October (i.e. 2months and 4months frozen storage period). Upon thawing, the meat was processed into mince following the same procedure used for the first trialand displayed for a fiveday period under retail display conditions. Frozen duration and gender had no effect (P>0.05) on the proximate composition of fallow deer meat. The total amount of saturated fatty acids (SFA) increased and total amount of poly unsaturated fatty acids (PUFA) decreased as frozen duration and display day increased (P<0.05). Frozen duration affected (P<0.01) lipid oxidation and percentage oxy-myoglobin. Mince pH and all colour parameters (L*, a*, b*,hue and chroma) differed (P<0.05) between treatments on day zero and three. Display day was a significant factor (P<0.05) on all measured parameters. By day three all parameters except pH showed signs of extended oxidation and discolouration as evidenced by reduced redness, decreased colour intensity and high TBARS values. This study showed that prolonged frozen storage negatively affects the colour and lipid stability of meat and increases oxidation of PUFAs during frozen storage. However, the study also suggests that although frozen/thawed meat has a shorter retail display shelf life, the proximate composition of the meat remains unchanged.
Glycolytic potential and meat quality from Dorper and Merino sheep.
(University of Fort Hare, 2015) Stempa, Thuthuzelwa; Muchenje, V.
The objective of the study was to determine glycolytic potential and meat quality from Dorper and Merino sheep of both sexes slaughtered at a commercial abattoir. Dorper (n=52) and Merino (n= 48) breeds aged eight years, consisting of 50 intact rams and 50 non-pregnant ewes were used in the study. The sheep used in the study were reared, transported and lairised under identical conditions. Blood samples were collected at exsanguination for the measurement of glucose, lactate and cortisol levels. Samples were also collected from the Muscularis longmissius thoracis et lumborum (LTL) for the measurement glycogen, lactate levels, pH decline and colour. Correlations amongst blood stress indicators, muscle metabolites and meat quality attributes were also determined. Sex and breed had no effect on muscle glycolytic potential, glycogen and lactate levels from Dorper and Merino sheep of both sexes at the abattoir. Although sex and breed had an effect on pre-slaughter stress indicators (lactate and cortisol) collected at exsanguination. Ewes had higher levels of blood lactate (7.4 3 ± 0.49 mmol/L) and cortisol (293.92 ± 14.32 nmol/L) than the rams which had (5.19 ± 0.49 mmol/L) and (179.50 ± 14.32 nmol/L) lactate and cortisol levels, respectively. Furthermore, higher levels of lactate were observed in Dorper (7.54 ± 0.42 mmol/L) compared to the Merino sheep (4.97 ± 0.49 mmol/L). Meat pH decline and colour were also significantly affected by sex and breed. Ewes had higher levels of at pH45 minutes post slaughter iii (7.05 ± 0.04), pH3 hours (6.45 ± 0.04) , pH24 hours (6.00 ± 0.03), a* (14.31 ± 0.33) , b* (8.84 ± 0.29), H* (31.47 ± 0.73) and C* (16.75 ± 0.24) compared to the rams which had pH45 minutes (6.44 ± 0.04), pH3 hours (6.12 ± 0.04), pH24 hours (5.88 ± 0.03), a* (12.25 ± 0.33), b* (7.00 ± 0.29), H* (29.36 ± 0.73) and C* (14.15 ± 0.42) values. Moreover, Merino sheep had higher levels of L* (38.17 ± 0.48) and H* (31.59 ± 0.74) compared to the Dorper which had (36.39 ± 0.46) and (29.33 ± 0.71) L* and H* values, respectively. Blood cortisol was also positively correlated (P < 0.05) to glucose (r = 0.27), lactate (r = 0.37) but was negatively correlated (P < 0.001) to meat lightness (r = -0.44). Furthermore, blood cortisol was positively correlated (P < 0.001) to pH45 (r = 0.34), pH24 (r =0.22), meat yellowness (r = 0.24) and chroma (r = 0.37), but was negatively correlated to meat lightness (r = -0.47). Glycolytic potential was positively correlated (P < 0.001) to muscle glycogen levels (r = 0.66) and muscle lactate (r = 0.71).
Sheep flock structure, dynamics, management practices, and wool production under bush encroached and non-encroached areas of the Eastern Cape Province, South Africa
(University of Fort Hare, 2016) Kom, Lubabalo
The main objective of the study was to investigate sheep productivity under bush encroached and non-encroached areas. The study was conducted in two communal areas, namely Idutywa (Mbewuleni village), which represented an open grassland with no encroaching woody species, and Alice (Sheshegu village) which was a bush encroached site. The purposive sampling method was used to select farmers with wool producing sheep who participated in the study. Experiment one employed a structured questionnaire to collect data on sheep flock composition, dynamics and management practices. A total number of 147 respondents were interviewed (73 in Mbewuleni village and 74 in Sheshegu village). The surveys revealed that just above three quarters of the households were male headed with close to half of the respondents being pensioners. Extensive farming was the production system employed across the two villages with community grazing as their source of feed. The sheep were allowed to graze separately during the grazing period with no other livestock such as cattle. The farmers experienced feed shortage, especially in the winter months and they prioritized feeding their lambs and ewes during this period. Shearing was done once a year in September or October. In both villages there was no controlled breeding and the lambing occurred during the winter period. It was found that the non-encroached site (Idutywa) had a significantly (P<0.05) higher number of sheep with 14% of the households having numbers above 121 sheep, while in Sheshegu about 8% of household above 121sheep. The major causes of mortality across the villages were cold weather, drought, predation and diseases. The interviewed households across the two villages mentioned that they dipped their sheep monthly. In the second study, a sample of 110 non-descript sheep breeds were randomly selected from the two villages (10 of each sex and each age group (which is 2 teeth, 4 teeth and 6 teeth) from each village with the exception of the 4 teeth old ewes from Sheshegu). The fleece samples were obtained from the selected sheep in October. The quantity and quality were determine based on wool weight, fibre diameter, colour, staple length, and clean wool. The results of the data analysis showed that the site had a statistically significant (P<0.05) difference on wool quantity between Sheshegu and Mbewuleni villages (2.8164kg and 1.6940kg), whilst the difference based on sheep sex was not significant (P>0.05), respectively. The older sheep produced significantly (P<0.05) higher amounts of wool compared to the younger animals. Wool quality was shown to be affected by locality in all parameters except for comfort factor. The clean yield effects were observed to be particularly more significant (P<0.05) when it came to the clean yield with Sheshegu sheep producing greater clean yield than their Mbewuleni counterparts. There was a significant (P<0.05) differences in the interaction of village and sex for crimp length (males had higher values) whereas that of village and age did not affect (P>0.05) the yield and crimp length. It was concluded from this study that age, sex and weight are the factors that affected wool production (quantity and quality). However, differences were not statistically significant (P>0.05) for effects of sex on wool quantity. Wool quality on the other hand was shown to be dependent on locality across all parameters with the exception of the comfort factor. Clean yield was higher in encroached as compared to non-encroached site. The conclusions from the study were that locality affected sheep flock structure and dynamics, because the encroached site had fewer numbers of sheep compared to the non-encroached site. In addition, the quantity and quality of wool produced differed with site, encroached site values being significantly different (P<0.05) to that from the non-encroached site.
Sheep production practices, flock dynamics, body condition and weight variation in two ecologically different resource-poor communal farming systems.
(University of Fort Hare, 2010) Mapiliyao, Luke
The objective of this study was to determine sheep production practices, constraints, flock dynamics, body condition and weight variation in two ecologically different resource-poor communal farming systems of the Eastern Cape Province of South Africa. Mean sheep flock sizes per household were not significantly different between the two ecologically different areas (villages); Gaga (19.0±3.10) and Sompondo (18.3±3.10). Shortage of feed, disease and parasite were reported the most important constraints across the two villages. In both villages, sheep housing was poorly constructed using acacia brushwoods. Fewer farmers owned rams: the rams to ewes ratio for the two villages were 1:20, 1:19 for Gaga and Sompondo, respectively. The low ram: ewe ratios reported suggest that inbreeding might have been reducing productivity of their flocks. There was also uncontrolled breeding due to undefined and mating seasons. Gall sickness, heart water and footrot caused most of the sheep mortalities. Dohne Merinos were the common genotypes in the two villages. Total entrances for each flock were higher (p < 0.05) in hot-dry season and hot-wet season than in other seasons. Most of the entrances were lambs and were born in hot-dry season (September) and cool-dry season (June) for larger flocks (10.90 ± 3.02) and for small flocks (3.65 ± 3.02). High lamb mortalities were experienced in the post-rainy (April) and hot-wet (December) season. There was a significant interaction between season and flock size. Most of the sales occurred in the hot-wet season. Ecological area had significant effect on sheep production iii potential (p < 0.05) in both flock classes. The average sheep production efficiency (SPE) value for Gaga and Sompondo were 0.50 ± 0.116 and 0.50 ± 0.096 respectively. The SPE for large flock was higher (p < 0.05) by season and flock size. Large flocks had a higher (p < 0.05) SPE values and the SPE ranged from 1.11 ± 0.193 in April, a post-rainy season month to 1.55 ± 0.193 in December, a hot-wet season month. Lamb mortalities constituted the greater part of outflows. High lamb mortalities occurred in hot-wet (December), hot-dry (September) and post-rainy (April) seasons. There was a significant interaction between season and age of sheep on body weight of sheep. Highest (p < 0.05) body weights were recorded in the post-rainy and autumn season in both lambs and ewes. It is therefore very important to come up with affordable interventions which take into play ecological differences of the areas for improved nutritional status of sheep in communal areas which will lead to improved sheep productivity and the poor-resourced farmer human nutritional and livelihood.
Socio-economic contribution and health challenges of indigenous chickens in smallholder systems
(University of Fort Hare, 2016) Zamxaka, Chuma Wande
Indigenous chickens are kept for various socio-economic purposes by the majority of households in the developing countries. However, their contribution to the livelihoods of the households has been observed by a number of researchers to be bolow their potential. Therefore, main objective of this study was to determine the contribution of the indigenous chickens towards the livelihoods of the rural people and to establish the health challenges of these chickens. The study was conducted in two phases and in two villages, a coastal one (Gcina) and inland site (Ngcingcinikhwe). Phase one was through the use of a structured questionnaire, while phase two included the seasonal collection of specimens and lab analyses to determine disease and parasite prevalence patterns. The location and seasonal effects on disease and parasite prevalence were analyzed. In the first phase of the study, the socio-economic statuses of the two communities were measured by determination of household income levels, main source of income and food security status. The main source of income in 80 percent of households was government social welfare grants and the average food security scores, which are indicative of the application of food shortage coping strategies, were 22.8 and 27.3 in Gcina and Ngcingcinikhwe, respectively. In addition, the contribution of indigenous chickens to the livelihoods of selected locations was measured by investigation of selling and consumption frequencies of indigenous chickens and their eggs. It was observed that in Gcina and Ngcingcinikhwe, 55 percent and 48 percent of households sold chickens, respectively, while 11 percent and 15 percent of households sold eggs in Gcina and Ngcingcinikhwe, respectively. Furthermore, 90 percent and 78.7 percent of households in Gcina and Ngcingcinikhwe, respectively, consumed indigenous chicken meat once a month while 77.8 percent and 72.4 percent of households in Gcina and Ngcingcinikhwe, respectively, consumed eggs once a month. In addition, average flock sizes observed in Gcina and Ngcingcinikhwe were 8.3 and 10.4 chickens, respectively, and chickens were allowed to scavenge for their feed with maize offered as the only supplement. An average of 11.6 and 11.7 eggs were set for hatching in Gcina and Ngcingcinikhwe, respectively, and the average hatching rate was 78.4 percent in Gcina while it was 71.8 percent in Ngcingcinikhwe. However, the average chick survival rate to growing phase was 55 percent in Gcina and 59.5 percent in Ngcingcinikhwe. This low chick survival rate was attributed to disease and parasite infestation. Furthermore, the respondents mentioned respiratory and nervous symptoms as the most commonly observed disease symptoms while worm infestation was least mentioned as a health challenge. Furthermore, the respondent alluded to the fact that symptoms of ill-health were mostly observed in summer and autumn. However, scientific determination of disease and parasite prevalence mostly contradicted the assertions of the respondents with regards to disease and parasite prevalence patterns as chickens had the lowest Newcastle disease (NCD) antibody levels in spring. Therefore, this was the season when they were most likely to exhibit NCD symptoms. Further observation was that the proximity to the coast did not have an effect on the level of NCD antibodies observed in chickens. Furthermore, de-wormed chickens had higher NCD antibody levels for a longer period compared to the those that were vaccinated only. It was, therefore, concluded that helminthes had a negative effect on the NCD antibody response to vaccination. To this end, an investigation of the prevalence of the helminthes revealed that there were three helminthes species (Railetina spp., Ascaridia galli and Heterakis gallinarum) were dominant during all seasons. However, the highest helminthes prevalence was observed in the inland location (Ngcingcinikhwe) in autumn. Futhermore, Salmonella positive feacal samples were reported in winter (20 percent) and summer (10 percent) in Gcina, whereas in Ngcingcinikhwe they were only reported in Spring (20 percent). In addition, the Salmonella serovars that were isolated from the positive samples were Salmonella entiritidis and Salmonella typhimurium. Based on this observation, it was concluded that there was a very low salmonella prevalence in the indigenous chickens of the two locations. In contrast, ecto-parasites were observed to be highly prevelant in both locations with season and proximity to the coast having effects on the species prevalence. Menopon gallinae exhibited the highest prevalence (90 percent) in the costal location in autumn whereas the fleas species (Echidnophaga gallenacea) was most prevalent in the inland area during spring. Furthermore, tick species (Amblyoma hebraeum) was most prevalent (70 percent) in the coastal area in spring and autumn, whereas another tick species (Argus spp) was most prevalent (40 percent) in the inland location in winter. In conclusion indigenous chickens had an insignificant contribution to the livelihoods of the people in the two study site due to health challenges that kept the flock sizes small and the production low. The health challenges were observed to differ by location and season. To this end, for an effective indigenous chicken health management strategy to be developed, the seasonal prevalence of diseases and parasites in a particular location needs to be established.

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