Superovulation and embryo collection in nulliparous Boer goat does immunized against a recombinant ovine alpha-subunit inhibin

With the purpose of eliciting a superovulatory response, 12 adult nulliparous Boer goat does were actively immunized against a recombinant a-subunit of ovine inhibin (roIHN-alpha; two injections of 100 mg 4 weeks apart). Another 12 control Boer goat does were treated with physiological saline and acted as controls. One year later the immunized animals were boostered by the administration of another dose (100 mg) of the immunogen. Following treatment, blood samples were collected twice weekly for the periods of 16 and 12 weeks, respectively, to monitor the inhibin binding ability with the aid of a radio-tracer binding assay. Throughout the experiment, estrus detection was conducted twice daily with the aid of an aproned intact buck. From the first day after treatment to 48 h after standing estrus, ovarian activity was monitored daily by transrectal ultrasonography. On alternate estrous cycles, does were mated and 6 days later flushed transcervically to recover embryos. All goats treated with the roIHN-alpha produced antibodies reactive to the native bovine inhibin tracer-the titre increasing from 2.9 +/- 0.4 to a maximum of 21.9 +/- 2.9% binding after the second injection. The antibody titre gradually subsided over the next 16 weeks. The booster injection restored an elevated antibody titre (11.7 +/- 0.4%), which was maintained until the end of the sampling period 12 weeks later. In the control goats only trace amounts of antibody were recorded throughout the trial. In the roIHN-alpha-immunized goats the number of follicles reaching a diameter of > 4 mm was 14.6 +/- 1.2 per doe. A positive correlation was recorded between the follicle number and antibody titre (r=0.61; P < 0.01). The number of follicles ovulating per doe (6.9 +/- 0.7) followed the same tendency-however, the proportion decreased with increasing follicle numbers. A relatively weak correlation was recorded between the inhibin binding ability and number of ovulations (r=0.27; P < 0.05). In the control goats the majority (92%) of follicles exceeding 4 mm in diameter ovulated (2.5 +/- 0.1 follicles/doe). Embryo collection proved unsatisfactory (42% versus 39% recovery for immunized and control animals, respectively)-presumably because the uterine lumen of the nulliparous does was too narrow to permit effective flushing. In the group of immunized goats the occurrence of short estrous cycles (< 15 days) recorded was 34% versus only 6% in the controls. Overall, immunization of goats against roIHN-alpha led to an almost six-fold increase in number of ovarian follicles, a three-fold increase in ovulations and, despite the low recovery rate, a more than three-fold increase in ova or embryos recovered. It may be concluded that treatment of female goats with roIHN-alpha leads to an inhibin antibody response, accompanied by enhanced ovarian activity. The response was, however, accompanied by a large proportion of retained follicles and a high incidence of short estrous cycles. These problems need to be further investigated before rendering the method fit for application in embryo transfer programs in goats. (C) 2007 Elsevier B.V. All rights reserved.

Composition, color, and texture of Thai indigenous and broiler chicken muscles

Chemical compositions and physical properties of mixed-sex Thai indigenous (Gallus domesticus) and broiler (commercial breed, CP707) chicken biceps femoris and pectoralis muscles were determined. Indigenous chicken muscles contained higher protein contents but lower fat and ash contents compared to broiler muscles (P < 0.001). The amino acid profile of the indigenous chicken muscles was similar to that of the broiler muscles except they were slightly richer in glutamic acid (P < 0.05). The indigenous chicken muscles contained more saturated and less polyunsaturated fatty acids than the broiler muscles. There were no differences in the monounsaturated fatty acid contents between the breeds. The total collagen contents of indigenous pectoralis and biceps femoris muscles were 5.09 and 12.85 mg/g, respectively, which were higher than those found in broiler pectoralis (3.86 mg/g) and biceps femoris muscles (8.70 mg/g) (P < 0.001). Soluble collagen contents were lower for indigenous pectoralis and biceps femoris muscles, 22.16 vs. 31.38% and 26.06 vs. 33.87%, respectively. The CIE system values of lightness (L*), redness (a*), and yellowness (b*) of indigenous chicken muscles were higher than those of broiler muscles. The shear values of indigenous chicken muscles either raw or cooked were higher than those of broiler muscles (P < 0.05). After cooking, the shear values decreased for broiler biceps femoris and pectoralis muscles (P < 0.05), whereas no change was observed for indigenous chicken biceps femoris muscle (P > 0.05). Shear values increased for indigenous chicken pectoralis muscle (P < 0.05).

Effect of heat treatment on changes in texture, structure and properties of Thai indigenous chicken muscle

Changes in texture, microstructure, colour and protein solubility of Thai indigenous and broiler chicken Pectoralis muscle stripes cooked at different temperatures were evaluated. The change in shear value of both chicken muscles was a significant increase from 50 to 80 degrees C but no change from 80 to 100 degrees C. A significant decrease in fibre diameter was obtained in samples heated to an internal temperature of 60 degrees C and the greatest shrinkage of sarcomeres was observed with internal temperatures of 70-100 and 80-100 C for broiler and indigenous chicken muscles, respectively (P < 0.05). Cooking losses of indigenous chicken muscles increased markedly in the temperature range 80-100 C and were significantly higher than those of the broiler (P < 0.001). With increasing temperature, from 50 to 70 degrees C, cooked chicken muscle became lighter and yellower. Relationships between changes in sarcomere length, fibre diameter, shear value, cooking loss and solubility of muscle proteins were evaluated. It was found that the solubility of muscle protein was very highly correlated with the texture of cooked broiler muscle while sarcomere length changes and collagen solubility were important factors influencing the cooking loss and texture of cooked indigenous chicken muscle. (c) 2004 Elsevier Ltd. All rights reserved.

Microstructure and thermal characteristics of Thai indigenous and broiler chicken muscles

The microstructure and thermal characteristics of Thai indigenous (Gallus domesticus) and broiler chicken (commercial line CP707) biceps femoris and pectoralis muscles were determined. Perimysium thicknesses were 14.2 mum for biceps femoris muscle and 7.10 mum for pectoralis muscle of indigenous chicken muscles, thicker than those of broiler muscles, which were 9.93 mum for biceps femoris muscle and 3.87 mum for pectoralis muscle (P < 0.05). Five endothermic peaks with peak transition temperatures (T-p) of 54.9, 61.7, 65.4, 70.6, and 76.1degreesC were obtained for broiler pectoralis muscle, whereas only 3 endothermic peaks (T-P of 56.6, 62.6, and 74.9degreesC were obtained for broiler biceps femoris muscle. Thai indigenous biceps femoris and pectoralis muscles had endothermic peaks with T-P ranges of 53.5 to 54.8, 60.7 to 61.9, and 75.9 to 76.9degreesC. The fiber diameters of Thai indigenous chicken muscles were greater (P < 0.05) than those of the broiler, 31.7 vs. 20.4 mum for biceps femoris muscle and 28.9 vs. 26.6 pm for pectoralis muscle, respectively. After cooking at 80degreesC for 10 min, the fiber diameter of indigenous chicken muscles significantly decreased while those of the broiler significantly increased. The mean of sarcomere lengths of the raw muscles ranged from 1.56 to 1.64 mun and decreased to 0.92 to 1.32 mum (P < 0.001) for broiler muscles and 1.22 to 1.35 mum (P < 0.001) for indigenous chicken muscles after cooking. The perimysium and endomysium of broiler muscles melted after cooking at 80degreesC, however, only slight disintegration was observed in these tissues in the indigenous chicken muscles.

Reducing fouling during UHT treatment of goat's milk

Whole fresh goat's milk was heat treated at 135 degrees C for 4 s using a miniature UHT plant. The temperature of the milk in the preheating and sterilizer sections, and the milk flow rate were monitored to evaluate the overall heat transfer coefficient (OHTC). The decrease in OHTC was used to estimate the extent of fouling. Goat's milk fouled very quickly and run times of the UHT plant were short. The use of sodium hexametaphosphate, trisodium citrate and cation exchange resins to reduce ionic calcium prior to UHT processing, increased the pH and alcohol stability of the milk and markedly increased the run time of the UHT plant.

Volatile flavour profile of goat meat extracted by three widely used techniques

Three procedures for the isolation of volatiles from grilled goat meat were compared: dynamic headspace entrainment on Tenax TA, simultaneous steam distillation-extraction, and solid-phase microextraction. Headspace entrainment on Tenax TA extracted the highest number of Maillard-derived volatile compounds. Two hundred and three volatile components were identified: 159 are reported for the first time in goat meat. Most of the volatiles detected (155) were lipid oxidation products, such as hydrocarbons, aldehydes, alcohols, ketones, carboxylic acids and esters. Forty-eight Maillard-derived compounds were identified. comprising pyrazines, pyrroles, thiophenes, furanthiol derivatives, alkyl and alicyclic sulphides, pyridines, and thiazoles. Some reported character impact compounds of cooked meat, e.g., 12-methyltridecanal, (EE)-2,4-decadienal, methional, and dimethyl trisulphide were identified in the volatile profile of goat meat, together with a series of C-2 to C-5 alkylformylcyclopentenes, which have been reported in cooked chicken, pork, beef and lamb, as being important for the characteristic flavour impression of different animal species. (C) 2009 Published by Elsevier Ltd.

The evolution of indigenous contractors in Ghana

This paper provides some preliminary insights into the emergence and development of indigenous general contractors in Ghana. General contracting is the means by which an individual or organisation takes responsibility for supplying all of the materials, labour, equipment and services necessary for the construction of a project. Whereas the development of general contracting in places like the UK is well documented, the evolution of contractors in Ghana is not clearly articulated in the literature. Therefore, the main question in this paper is: How did indigenous contractors evolve in Ghana? To examine and analyze the research question, a literature review on similar developments elsewhere was first carried out. This was followed by discussions and unstructured interviews with experienced construction practitioners in Ghana most of whom were Quantity Surveyors. Most interviewees narrated their knowledge of contractor development in Ghana dating back to around 1945. From the explanations given, it was possible to develop a general understanding of the research question and to make a qualitative interpretation of the respondents’ comments and to draw some conclusions. General contractors emerged rapidly in the Gold Coast (now Ghana) shortly after World War II. Most were Italian master craftsmen in Ghana who were capitalized by the British colonial government to develop infrastructure in the Gold Coast following devastating effects of the war. Some of the indigenous people learned from the Italians and also established construction firms. Thus, general contracting in Ghana has a relatively short history in comparison to countries like Britain where the profession developed rapidly in the early part of the 19th century in response to the industrial revolution. Although they may possess sufficient technical expertise, many indigenous contractors in Ghana today lack the capacity to carry out major projects because of low capitalization and poor organisational structures. The current construction market in Ghana is dominated by foreign contractors. To become major players in the market, indigenous Ghanaian contractors should build strong organisational structures and pursue mergers and joint venturing to boost their financial, technical and managerial capacity.

Determination of some water-soluble aroma precursors in goat meat and their enrolment on flavour profile of goat meat

Selected water-soluble precursors, including sugars, free amino acids and nucleotides, were quantified in raw and cooked goat meat, as a part of a study which the main aim was to better understand the aroma formation in goat meat. When compared with the same precursors in beef, lamb and chicken, levels in goat meat were generally similar, except for fructose and glycine, which were present at higher concentrations in goat meat. Fructose, glucose, IMP, and cysteine suffered the greatest losses during the cooking process and seem to be most involved in aroma formation in goat meat. The effects of these precursor changes on the volatile compound composition and formation process of them on cooked goat meat are discussed.

Comparison of heat stability of goat milk subjected to ultra-high temperature and in-container sterilisation

Goatmilk with and without stabilizing salt was subjected to in-container and UHTsterilization. Heatstability was assessed by measuring the amount of sediment in the milk. Without stabilizing salts, goatmilk usually produced less sediment when subjected to in-containersterilization compared with UHT processing. Addition of stabilizing salts up to 12.8 mM resulted in a progressive increase in sediment for in-containersterilization. In contrast, adding stabilizing salts at 6.4 mM initially reduced sediment formation in UHT-treated milk but addition of stabilizing salts at 12.8 mM increased sediment formation. Adding stabilizing salts to goatmilk increased pH, decreased ionic calcium, and increased ethanol stability. Adding up to 2 mM calcium chloride increased sediment formation more after UHT treatment than after in-containersterilization. These results suggest that no single mechanism or set of reactions causes milk to produce sediment during heating and that the favored pathway is different for UHT and in-containersterilization processes. Poor heatstability could be induced both by increasing ionic calcium and by decreasing it. Ethanol stability is not a good indicator of heatstability for in-containersterilization, but it may be for UHTsterilization, if milk does not enter the region of poor heatstability found at low concentrations of ionic calcium.

The impact of livestock assets among indigenous communities: findings from a comparative model in Bolivia

Measuring poverty has occupied a lot of space in the development discourse. Over the years a number of approaches have been offered to capture the experience of what it means to be poor. However, latterly such approaches often ignore core assets. Indeed, the comparative impact of livestock vs. other core assets such as land and education on poverty has not been well explored. Therefore, the authors created an 'asset impact model' to examine changes to both tangible and intangible assets at the household level, with a particular focus on gender and ethnicity among communities residing in the Bolivian Altiplano. The simple model illustrates that for indigenous women, a 20 per cent increase in the livestock herd has the same impact on household income as increasing the education levels by 20 per cent and household land ownership by 5 per cent. The study illustrates the potential role of a productive, tangible asset, i.e. livestock, on poverty reduction in the short term. The policy implications of supporting asset-focused measures of poverty are discussed.

Participatory research approaches in the development of improved management practices in indigenous chickens production systems with smallholder farmers in Kenya

This thesis is concerned with development of improved management practices in indigenous chicken production systems in a research process that includes participatory approaches with smallholder farmers and other stakeholders in Kenya. The research process involved a wide range of activities that included on-station experiments, field surveys, stakeholder consultations in workshops, seminars and visits, and on-farm farmer participatory research to evaluate the effect of some improved management interventions on production performance of indigenous chickens. The participatory research was greatly informed from collective experiences and lessons of the previous activities. The on-station studies focused on hatching, growth and nutritional characteristics of the indigenous chickens. Four research publications from these studies are included in this thesis. Quantitative statistical analyses were applied and they involved use of growth models estimated with non-linear regressions for the growth characteristics, chi-square determinations to investigate differences among different reciprocal crosses of indigenous chickens and general linear models and covariance determination for the nutrition study. The on-station studies brought greater understanding of performance and production characteristics of indigenous chickens and the influence of management practices on these characteristics. The field surveys and stakeholder consultations helped in understanding the overarching issues affecting the productivity of the indigenous chickens systems and their place in the livelihoods of smallholder farmers. These activities created strong networking opportunities with stakeholders from a wide spectrum. The on-farm farmer participatory research involved selection of 200 farmers in five regions followed by training and introduction of interventions on improved management practices which included housing, vaccination, deworming and feed supplementation. Implementation and monitoring was mainly done by individual farmers continuously for close to one and half years. Six quarterly visits to the farms were made by the research team to monitor and provide support for on-going project activities. The data collected has been analysed for 5 consecutive 3-monthly periods. Descriptive and inferential statistics were applied to analyse the data collected involving treatment applications, production characteristics and flock demography characteristics. Out of the 200 farmers initially selected, 173 had records on treatment applications and flock demography characteristics while 127 farmers had records on production characteristics. The demographic analysis with a dissimilarity index of flock size produced 7 distinct farm groups from among the 173 farms. Two of these farm groups were represented in similar numbers in each of the five regions. The research process also involved a number of dissemination and communication strategies that have brought the process and project outcomes into the domain of accessibility by wider readership locally and globally. These include workshops, seminars, field visits and consultations, local and international conferences, electronic conferencing, publications and personal communication via emailing and conventional posting. A number of research and development proposals were also developed based on the knowledge and experiences gained from the research process. The thesis captures the research process activities and outcomes in 8 chapters which include in ascending order – introduction, theoretical concepts underpinning FPR, research methodology and process, on-station research output, FPR descriptive statistical analysis, FPR inferential statistical analysis on production characteristics, FPR demographic analysis and conclusions. Various research approaches both quantitative and qualitative have been applied in the research process indicating the possibilities and importance of combining both systems for greater understanding of issues being studied. In our case, participatory studies of the improved management of indigenous chickens indicates their potential importance as livelihood assets for poor people.