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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Effects of Direct-Fed Microbial Products, Butyrate, and Botanicals on Performance and Health of Broilers Raised on Used Pine Shaving Litter

Lewis, Meredith D. 29 August 2018 (has links)
Two experiments were conducted to determine the effects of various alternatives to antibiotics in broilers grown on used litter on performance, intestinal lesion scores, body composition, and cecal volatile fatty acid (VFA) concentrations. The first experiment used a corn-soybean meal based basal diet to generate a negative control (NC) diet (without treatment), a Bacillus licheniformis probiotic containing diet (NC + 0.10% DFM1), and four diets that contained various concentrations of a Bacillus subtilis probiotic (NC + 0.05% DFM2, NC + 0.10% DFM2, NC + 0.20% DFM2, and NC + 0.40% DFM2). Experimental diets were fed to broilers over a 42-day period. Body weight gain (BWG) was depressed from d 0-28 and d 0-42 with supplementation of 0.10% DFM1 and 0.05% DFM2 compared to NC fed birds (P ≤ 0.05), with no differences among the remaining treatments and the NC fed birds (P > 0.05). Feed intake (FI) and mortality corrected feed efficiency (FEm) were not different over the 0-42 day period. No differences in oocyst shedding, lesion scores, body composition or cecal VFA production were observed (P > 0.05). Consistently low lesion scores were indicative of a mild coccidial challenge. The second experiment utilized a corn-soybean meal basal diet to generate experimental treatment diets. The basal diet without additional supplements was fed to two groups of control birds, one on clean pine shaving litter (PC) and a second on used litter (NC). Treatment groups were fed the same diet, supplemented with butyrate for the first 14 days (NC + But 0-14), botanicals from d 15-43 (NC + Bot 15-43), butyrate from d 0-14 and botanicals from d 15-43 (NC + But 1-14/Bot 15-43), and butyrate from d 0-43 (NC + But 1-43). Butyrate supplementation reduced BWG from d 0-14 (P ≤ 0.05), but there were no differences in BWG from 0-43 d (P > 0.05). Feed intake was reduced for the NC + But 0-14 group from d 0-43 in comparison to both PC and NC. Lesion scores in the jejunum were reduced with supplementation of butyrate alone, fed for either d 0-14 or d 0-43 (P ≤ 0.05) and is an indication of a mild coccidial infection due to the used litter. Although there were no significant differences among treatments, overall performance was above industry expectations, likely due to the mild fall weather. These two experiments indicate that there are numerous factors involved in the efficacy of antibiotic alternatives, at least partially explaining the inconsistent results observed in the published literature. / Master of Science / Recently, increased regulations and customer demand have restricted and reduced the use of antibiotics in the poultry industry. Historically, antibiotics were used in poultry feed at sub-therapeutic levels to improve performance and prevent the incidence of clinical and subclinical disease. Since the reduction of antibiotic use, many producers have experienced reduced performance resulting in reduced profits. The limited use of antibiotics can also present an animal welfare issue associated with increased sub-clinical and clinical disease. Many researchers are investigating alternative feed additives that will both improve performance and prevent disease, including probiotics, organic acids, and botanical products. Previous research has demonstrated the ability of these alternative to positively, if inconsistently, influence the performance and health of broiler chickens. Therefore, the objective of this thesis is to investigate the effects of two probiotic bacteria fed at various concentrations and the effects of butyric acid and botanicals, fed alone, or in combination, on the performance, intestinal lesion scores, body composition, and cecal volatile fatty acid concentrations of broiler chickens raised on used litter. In these experiments, the used litter is representative of a mild disease challenge that would likely be present in a commercial poultry setting. Overall, there were few differences with the treatment of broilers with probiotic bacteria, but the lowest inclusions slightly reduced body weight gain compared to the control fed broilers. Butyric acid supplementation reduced body weight gain over the first 14 days, but these differences were no longer observed over the 0 to 42 day period. Although performance was not improved, butyrate did result in reduced intestinal lesion scores from the middle section of the small intestine, indicating potential health benefits with butyrate treatment. Overall, the data presented in this thesis suggest that there are a variety of factors that can alter the effectiveness of these alternatives in broiler production and care should be used in selection of antibiotic replacement tools.
112

Molecular Cloning and Functional Characterization of a Turkey Intestinal Peptide Transporter (tPepT1), and Developmental Regulation of PepT1 Expression in Turkey and Broiler Embryos

Van, Ling 30 September 2002 (has links)
A cDNA clone encoding a turkey intestinal peptide transporter, tPepT1, was isolated from a turkey small intestinal cDNA library by screening with our chicken PepT1 (cPepT1) cDNA probe. The tPepT1 cDNA is 2,921-bp long and encodes a 79.4 kDa protein of 714 amino acids (AA) with 12 predicted transmembrane domains. The isoelectric point (pI) of tPepT1 is 5.9, which is much lower than that of PepT1 cloned from chicken (pI = 7.5) and other species. The AA sequence of tPepT1 is 94.3% identical to cPepT1 and ~ 60% identical to PepT1 from rat, sheep, rabbit, and human. Using a two-electrode voltage-clamp technique in Xenopus oocytes expressing tPepT1, Gly-Sar transport was pH dependent, but independent of Na+ and K+. For the dipeptides Gly-Sar and Met-Met, the evoked inward currents indicated that the transporter was saturable and had a high affinity for these substrates. However, transport of the tetrapeptide, Met-Gly-Met-Met, exhibited a possible substrate inhibition. To study developmental regulation of PepT1 in broiler and turkey embryos, 12 Nicholas turkey or Cobb x Cobb broiler embryos (six males and six females) were sampled daily from 5 d before hatch to the day of hatch (d 0). The abundance of PepT1 mRNA in the small intestine was quantified densitometrically from northern blots after hybridization with full-length cPepT1 and tPepT1 cDNA as probes. There was a quadratic increase (P < 0.001) in PepT1 mRNA abundance with age in turkey and broiler embryos. The relative increase in abundance of PepT1 mRNA in intestinal tissue from 5 d before hatch to d 0 was much less in the turkey than in the broiler (3.2-fold vs 14-fold). The dramatic increase in PepT1 mRNA abundance indicates a developmental regulation of the PepT1 gene and that there may be a crucial role for PepT1 in the neonatal chick and poult. / Master of Science
113

Effects of dietary Ca concentration on the performance of broiler chicks fed various sources of dietary P with and without phytase supplementation

Fritzlen, Cooper January 2021 (has links)
Two experiments were conducted to determine the effects of high dietary calcium (Ca) on broiler chicks fed low phosphorus (P) diets from either nonphytate (nPP) or phytate P (PP) with or without phytase. The response criteria that were analyzed was bird performance, tibia ash, Ca and P digestibility and duodenal P transporter mRNA abundance. Newly hatched broiler chicks were housed in raised-wire starter batteries (65.8 in2) for 16 d. Each experiment had 12 treatments were replicated 6 times using 8 chicks per cage that resulted in a total of 576 Cobb 500 chicks. Experiment 1 had a 3x2x2 factorial arrangement included 3 P treatments (0.225%nPP, 0.225 + 0.1%P from nPP and 0.225 + 0.1%PP), 2 concentrations of Ca (0.9 vs.1.7%Ca) and either (0 or 1,000 FTU of phytase). Experiment 2 also had a 3x2x2 factorial arrangement but set closer to commercial standards (0.325% nPP, 0.325 + 0.1% P from nPP and 0.325 + 0.1% P from PP), 2 concentrations of Ca (0.9 vs.1.4% Ca) with and without phytase (0 or 1,000 FTU of phytase). Body weight gain (BWG), feed intake, feed conversion and mortality were calculated over the 16d period. On 16d, all remaining chicks were euthanized, and the right tibia was analyzed for tibia ash weight (TAW) in mg/tibia and expressed as a percentage (TAP). All data were analyzed as a 3x2x2 factorial using ANOVA in JMP 14 (P ≤ 0.05). In Experiment 1, the phytase interactions were driving FI, which increased BWG (P ≤ 0.05). However, the phytase interactions did not influence bone mineralization (P ≤ 0.05). So, the diet is potentially more appetizing with phytase supplementation. Calcium x phosphorus interaction was driving bone mineralization, but not influencing BWG or FI (P ≤ 0.05). Additionally, bone mineralization was impacted when additional P was put into high Ca diets (P ≤ 0.05). Phytase upregulated P transporter mRNA abundance in normal Ca diets, but the results were muted in high Ca diets (P ≤ 0.05). Experiment 2 used more practical P and Ca conditions to validate the responses from Experiment 1 with the understanding that the potential responses would be blunted. The addition of phytase improved tibia ash when Ca and P were unbalanced (P ≤ 0.05). High concentrations of Ca lowered BWG and FI, but again the addition of phytase to the diet had a more beneficial effect (P ≤ 0.05). Diets with reduced P had an improved P and Ca digestibility and upregulation of P transporter mRNA abundance (P ≤ 0.05). Also, the addition of phytase improved both P and Ca digestibility and downregulated P transporter mRNA abundance (P ≤ 0.05). Overall, both experiments exhibited that source of P did not influence performance but did influence tibia ash. High calcium had a negative effect on performance and digestibility. However, phytase was able to ameliorate negative impacts of high calcium diets. The multiple interactions of Ca, P and phytase indicate a complex relationship among the three factors that require balancing when looking for optimal conditions commercially, especially to maximize performance and skeletal health while balancing cost and environmental considerations. / M.S. / Phosphorus and calcium have many important functions within the body including energy metabolism, cell signaling, bone development and mineralization. When deficiencies of these minerals are seen in broiler chickens a decrease in skeletal health will be one of the first visual signs, where commercially will show up as leg issues. However, meeting the dietary requirements for P and Ca is not a simple task. A considerable amount of P in poultry diets is in the form of phytate P, which is an organic form of P that is hard to digest by the bird. In most cases inorganic P must be fed to meet the broiler requirements for P because its easily absorbed by the animal. Another way to increase the utilization of these minerals is with the supplementation of phytase into the diet. Supplementing phytase allows for a decrease in the amount of inorganic P being added to the diet. The decrease of inorganic P put in the diet saves industries money and is more beneficial for the environment. The addition of phytase also increases the utilization of Ca from the diet, which is brought into consideration during the formulation of the diet. However, there is still a potential for over supplementation of Ca commercially if there are feed mixing errors or high concentrations of Ca from new feed additives. Over supplementation of Ca can lead to many issues which include reduced nutrient digestibility, reduced performance, and an influence on the effectiveness of phytase. Therefore, the effects of feeding high dietary Ca on broiler chicks fed phosphorus from either nonphytate P or phytate P sources with or without phytase were determined with a focus on bird performance, tibia ash, Ca and P digestibility and duodenal P transporter mRNA abundance. Across both experiments source of P did not influence performance but did influence tibia ash. High calcium had a negative effect on performance and digestibility. However, phytase was able to ameliorate negative impacts of high calcium diets. The multiple interactions of Ca, P and phytase indicate a complex relationship among the three factors that require balancing when looking for optimal conditions commercially, especially to maximize performance and skeletal health while balancing cost and environmental considerations.
114

The Effect of Dietary Phytic Acid Concentration and Phytase Supplementation on Performance, Bone Ash, and Intestinal Health of Broilers Vaccinated With a Live Coccidial Oocyst Vaccine

Lehman, Regina N. 12 December 2011 (has links)
The role of nutrition in providing optimal broiler growth and intestinal health is essential, especially during stress or disease challenge. Feed enzymes are useful for improving performance of poultry, particularly when nutrition, management, or health status is not favorable. The objective of the following experiments was to evaluate the effect of dietary phytic acid (PA) and phytase on the performance and intestinal health of birds that were vaccinated with a live coccidial oocyst vaccine. For each experiment, half of the chicks were spray-vaccinated at day-of-hatch with Coccivac®-B and grown out in floor pens with ad libitum access to diets formulated to meet Cobb nutrient recommendations. In the first experiment, birds were given one of three diets that included different levels of a PA solution to obtain dietary PA levels of 0.74, 0.87, and 1.12% for low, medium, and high PA diets, respectively. In the second experiment, two levels of PA were included to obtain dietary PA levels of 0.75 and 1.05% for low and high PA diets, respectively. In addition, phytase was added over the top to half of the diets at 1000 FTU/kg, resulting in four diets: low PA without phytase, low PA with phytase, high PA without phytase, and high PA with phytase. Live performance parameters including body weight, body weight gain, feed intake, feed conversion, and mortality were measured as well as tibia ash (experiment 2) and indicators of small intestinal health including morphology, apparent ileal amino acid digestibility (IAAD), and pH (experiment 2). The results presented here indicated that giving broilers vaccinated against coccidiosis a medium level of PA was detrimental to feed intake, body weight gain, and it induced necrotic enteritis (P ≤ 0.05). Adding phytase on top of nutritionally adequate diets did not improve performance (P ≥ 0.05), but did improve (P ≤ 0.05) apparent IAAD and morphology of the small intestine, especially in younger birds. In addition, it has been determined that important considerations in diet formulation also can include the phytate: protein as well as calcium: total phosphorus ratios, as these may critically affect how phytate impacts bird health and performance. / Ph. D.
115

Biological, Nutritional, and Processing Factors Affecting Breast Meat Quality of Broilers

Santiago, Hector Luis 22 February 2002 (has links)
A series of experiments were conducted to investigate the effects of certain biological, nutritional, and processing factors on breast meat quality of broilers. In the first experiment, the influence of genetic strain, plane of nutrition, and age at slaughter on breast meat quality was evaluated. Breast meat from a high yield line of broilers had lower pH at 24 h postmortem (PM), greater L*, a*, and b* values, lower water holding capacity (WHC), and higher expressible moisture (EM) than those of a line selected for rapid growth. Breast meat from birds processed at 42 d had lower WHC than those processed at 53 d, even though no differences in pH and L* values at 24 h were observed. No significant effects due to plane of nutrition on meat quality traits were observed. In Experiment two, the influence of strain and chilling methods (ice or air chilled) on breast meat quality was studied in broilers. Breast meat quality significantly differed among strains, with one of the strains evaluated having higher muscle pH, lower L* values, and higher WHC than the other strains. Ice-water chilling significantly reduced the rate and extent of PM pH decline, but had significantly lower WHC and higher EM than those from carcasses chilled by air. However, chilling conditions did not influence breast meat color. In Experiment three, the effects of strain and gender on breast muscle quality of broilers was studied. Meat quality traits were evaluated on both sexes of six genetic crosses of commercial strains. No significant differences in breast meat quality traits among strains were observed. However, differences between sexes were highly significant. The P. major muscles of females had lower pH values at all PM times, higher L*, a*, and b* values, and lower WHC than males. The P. minor of females had significantly lower pH, lower WHC, higher EM, but similar color L*, a*, and b* values than males. In Experiment four, the effects of strain, gender, and age at slaughter on breast meat quality were studied. Strain differences were observed in both sexes, but these differences did not show any specific relationship with the strain genotype. Breast muscles from a male pure line had superior meat quality, with higher muscle pH, and WHC, but higher L* values than the other strains. Significant differences in breast meat quality traits due to age at slaughter were also observed. Regardless of gender, breast muscle pH at 24 h PM and WHC decreased linearly with age, while breast muscle temperature and L* values increased in a linear fashion with advancing age at slaughter. No significant strain by age interactions were observed for any of the meat quality traits evaluated. The results of these studies indicate that commercial genotypes differ significantly in PM muscle metabolism and subsequent meat quality. The results also indicate that female broilers and older birds might be more susceptible to meat quality problems. / Ph. D.
116

Broiler Performance and Intestinal Alterations When Fed Drug-Free Diets

Sun, Xiaolun 19 August 2004 (has links)
A study was carried out to investigate the effects of a drug-free feeding program on broiler performances. A total of 2,496 Cobb 500 chicks were randomly assigned to one of four dietary treatments with each group replicated 13 times. The four diets evaluated were: 1) negative control (NC): basal diet without growth promoter or coccidiostat; 2) positive control (PC): diet 1 + Lincomycin; 3) Program 1 (PG1): diet 1 + Bio-Mos®, Vegpro®, MTB-100®, Acid Pak 4-Way®, and All-Lac XCL®; 4) Program 2 (PG2): diet 1 + Bio-Mos® and All-Lac XCL®. Additives were used at commercially recommended rates. All chicks were vaccinated with a live oocyst coccidia vaccine on d 0 at the hatchery. Four phases of feeding were used during the trial with changes occurring at d 14, 28, and 35. Performance values measured were body weight, feed intake, yield, and mortality, while body weight gain and feed conversation rate (FCR) were calculated. Chicks were challenged with coccidia at d 14 to evaluate the protective effect of the feeding programs and coccidia vaccination. Segments of duodenum, ileum, and ceca were removed to measure intestinal morphology. Final body weight gains of birds on PC (2.736 kg) were greater (P < 0.05) compared to NC (2.650 kg), while birds on PG1 (2.681 kg) and PG2 (2.710 kg) were similar to positive and negative control. Overall, feed intake was similar across the treatments with the exception of period 2 (15 to 28 days) when birds consumed more (P < 0.05) of PC and PG1 compared to NC. Cumulative FCR at d 35 and 49 was improved (P < 0.05) in birds consuming PC and PG2 when compared to NC. Overall, birds consuming NC had greater mortality (P < 0.05; 12%) compared to PC (7.6 %), PG1 (4.6%) and PG2 (6.7 %) with most of the mortality occurring from d 0 to d 28. Mortality for birds consuming PG1 was also lower (P < 0.05) compared to the PC. There were no dietary effects on lesion scores or yields of processed products at d 42 (females) or d 49 (males). Interaction of dietary treatments with age and days of age alone showed effects (P < 0.0001) on the morphology of duodenum, ileum, and ceca. Lamina propria in ceca was thicker (P < 0.008) in birds consuming NC compared to PG1 and PG2. This study indicated that feeding birds without growth promoters resulted in greater mortality and decreased performance compared to using an antibiotic, while Bio-Mos® in combination with All-Lac XCL® helped to reduce the negative effects. / Master of Science
117

Hydrodynamic Shock Wave: Decreasing Broiler Breast Aging Time

Meek, Kimberly I. 03 March 1998 (has links)
The Hydrodyne process was used to tenderize early de-boned broiler (EB) breasts. The first objective was to determine effects of explosive and distance of the explosive to the meat surface. EB breasts were removed immediately after initial chill (45 min post-mortem), stored for 24 hours, and subjected to one of four treatment combinations. Hydrodyne treatment of 350 g at 20 cm produced the greatest increase in Warner-Bratzler shear (1.9-cm wide strips) tenderness (28.3%), and was the only treatment to increase tenderness (peak force 4.3 kg) to a level equivalent (P>0.05) to aged controls (CA; peak force 3.1 kg). The second objective was to determine quality (tenderness, purge loss, cooking loss, and color) and sensory characteristics of Hydrodyne treated (HYD) broiler breasts. Initial pH values for CA (5.86) and EB (5.71) breasts were different (P<0.05). Warner-Bratzler and Lee-Kramer shear values (1.0-cm wide and thick strips) for CA (1.56 kg; 6.0 kg*mm/g, respectively) were different from HYD (3.7 kg; 11.0 kg*mm/g, respectively) and EB breasts (4.7 kg; 12.1 kg*mm/g, respectively). CA resulted in more tender, flavorful, and juicer breasts than HYD and EB. HYD was lower in initial moisture release than EB. EB breasts with significant tenderness problems can be tenderized by the Hydrodyne process based on instrumental shear results. However, higher levels of explosive may be required to optimize tenderness improvement of breasts that vary significantly in initial tenderness. Incorporation of this technology, once optimized, on an industry production level would benefit poultry processors in reducing or eliminating broiler breast aging. / Master of Science
118

Qualidade da carne de matriz pesada em final de ciclo de produção e tecnicas de agregação de valor /

Komiyama, Claudia Marie, 1978- January 2009 (has links)
Orientador: Ariel Antonio Mendes / Banca: Roberto de Oliveira Roça / Banca: Marcia Regina Boaro Martins / Banca: Hirasilva Borba / Banca: Rodrigo Garófallo Garcia / Resumo: O objetivo do trabalho foi avaliar as características de qualidades da carne de matrizes pesadas de descarte. Foram realizados três ensaios para se avaliar a qualidade da carne em final de ciclo produtivo. Todas as aves pertenciam a linhagem comercial Ross, procedentes de Uberlândia (MG) e Campo Verde (MT) com idade e peso médio de 479 dias e 3.971g, respectivamente. No Ensaio 1 foram coletados 120 peitos de matrizes em 6 coletas diferentes e avaliados os seguintes parâmetro: pH, cor, valor R, perda por gotejamento, capacidade de retenção de água e absorção de água, capacidade de emulsificação, perdas por cocção e força de cisalhamento. No Ensaio 2 foi realizado o teste sensorial da carne de peito de matrizes comparado a frangos de corte, sendo coletado 20 peitos de matrizes de descarte e 20 peitos de frangos de corte em abatedouro comercial. No Ensaio 3, foram avaliados a composição química, o teor de colesterol e o perfil de ácidos graxos da carne de matrizes pesadas de descarte. A carne de peito de matrizes apresentou valores médios do parâmetro valor de L* de 50,11. Para a capacidade de retenção, perda de peso por cozimento e força de cisalhamento, os valores médios foram 76,67, 17,92% e 4,94kgf/cm2 respectivamente. Na análise sensorial, a carne de matriz apresentou baixa intensidade de maciez (6,9), menor suculência (3,4) e mais elástica, borrachenta e difícil deglutição. A carne de matrizes apresentou percentagem de gordura, proteína, matéria seca, umidade, cinzas e colesterol de 1,39%, 24,26%, 27,71%, 72,29%, 1,42% e 72,59mg/100g, respectivamente. A carne de matrizes pesadas de descarte apresentou boas características de qualidade tecnológicas que possibilitam sua utilização como matéria-prima para a elaboração de industrializados. Além disso, apresentou composição química semelhante a da carne de frangos de corte, não possuindo altos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This present aimed to evaluate the meat quality characterists of spent breeder hens. There were realized three trials to evaluate meat trait of spent breeder hens. All birds were Ross stain, from Uberlândia city (MG) and Campo Verde city (MT) with age and weigth average of 479 days and 3.971g, respectively. In trial 1, there were evaluated: pH, color, R value, drip loss, water holding capacity, water absorption capacity, emulsifying capacity, cooking loss and shear force. In trial 2, it was realized the sensory test using breast meat of breeder hens compared to broiler chicken, collecting 20 spent breeder hen breast and 20 broiler chicken breast cropped in commercial processing plant. In trial 3, there were evaluate the chemistry composition, cholesterol value and fatty acid profile of spent breeder hens meat. Breeder hens meat presented L* value means of 50.11. To water retention capacity, cooking loss and shear force, means values were 76.67, 17.92% e 4.94kgf/cm2, respectively. In sensory test, breeder hens meat presented low intensity tenderness (6.9), lower juiciness (3.4) and elasticier, rubber and difficult to swallow. Breeder hens meat presented percent of fatty, protein, dry material, humidity, material mineral and cholesterol of 1.39%, 24.26%, 27.71%, 72.29%, 1.42% e 72.59mg/100g, respectively. Broiler hen meat presented good technology quality characteristics that it can be possible to use as meat for industry elaborated. Besides, this meat present chemistry composition equal of the meat of broiler chicken, do not hold high value of fat and cholesterol, hence these meat can be consider a meat with healthy characteristics. / Doutor
119

Qualidade da carne de matriz pesada em final de ciclo de produção e tecnicas de agregação de valor

Komiyama, Claudia Marie [UNESP] 13 March 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-13Bitstream added on 2014-06-13T20:25:13Z : No. of bitstreams: 1 komiyama_cm_dr_botfmvz.pdf: 2731486 bytes, checksum: f0ccba696b2148389d8d7f96334dc1d5 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / O objetivo do trabalho foi avaliar as características de qualidades da carne de matrizes pesadas de descarte. Foram realizados três ensaios para se avaliar a qualidade da carne em final de ciclo produtivo. Todas as aves pertenciam a linhagem comercial Ross, procedentes de Uberlândia (MG) e Campo Verde (MT) com idade e peso médio de 479 dias e 3.971g, respectivamente. No Ensaio 1 foram coletados 120 peitos de matrizes em 6 coletas diferentes e avaliados os seguintes parâmetro: pH, cor, valor R, perda por gotejamento, capacidade de retenção de água e absorção de água, capacidade de emulsificação, perdas por cocção e força de cisalhamento. No Ensaio 2 foi realizado o teste sensorial da carne de peito de matrizes comparado a frangos de corte, sendo coletado 20 peitos de matrizes de descarte e 20 peitos de frangos de corte em abatedouro comercial. No Ensaio 3, foram avaliados a composição química, o teor de colesterol e o perfil de ácidos graxos da carne de matrizes pesadas de descarte. A carne de peito de matrizes apresentou valores médios do parâmetro valor de L* de 50,11. Para a capacidade de retenção, perda de peso por cozimento e força de cisalhamento, os valores médios foram 76,67, 17,92% e 4,94kgf/cm2 respectivamente. Na análise sensorial, a carne de matriz apresentou baixa intensidade de maciez (6,9), menor suculência (3,4) e mais elástica, borrachenta e difícil deglutição. A carne de matrizes apresentou percentagem de gordura, proteína, matéria seca, umidade, cinzas e colesterol de 1,39%, 24,26%, 27,71%, 72,29%, 1,42% e 72,59mg/100g, respectivamente. A carne de matrizes pesadas de descarte apresentou boas características de qualidade tecnológicas que possibilitam sua utilização como matéria-prima para a elaboração de industrializados. Além disso, apresentou composição química semelhante a da carne de frangos de corte, não possuindo altos... / This present aimed to evaluate the meat quality characterists of spent breeder hens. There were realized three trials to evaluate meat trait of spent breeder hens. All birds were Ross stain, from Uberlândia city (MG) and Campo Verde city (MT) with age and weigth average of 479 days and 3.971g, respectively. In trial 1, there were evaluated: pH, color, R value, drip loss, water holding capacity, water absorption capacity, emulsifying capacity, cooking loss and shear force. In trial 2, it was realized the sensory test using breast meat of breeder hens compared to broiler chicken, collecting 20 spent breeder hen breast and 20 broiler chicken breast cropped in commercial processing plant. In trial 3, there were evaluate the chemistry composition, cholesterol value and fatty acid profile of spent breeder hens meat. Breeder hens meat presented L* value means of 50.11. To water retention capacity, cooking loss and shear force, means values were 76.67, 17.92% e 4.94kgf/cm2, respectively. In sensory test, breeder hens meat presented low intensity tenderness (6.9), lower juiciness (3.4) and elasticier, rubber and difficult to swallow. Breeder hens meat presented percent of fatty, protein, dry material, humidity, material mineral and cholesterol of 1.39%, 24.26%, 27.71%, 72.29%, 1.42% e 72.59mg/100g, respectively. Broiler hen meat presented good technology quality characteristics that it can be possible to use as meat for industry elaborated. Besides, this meat present chemistry composition equal of the meat of broiler chicken, do not hold high value of fat and cholesterol, hence these meat can be consider a meat with healthy characteristics.
120

Socio-economic analysis and profitability of small-scale broiler production enterprises in Vhembe District, Limpopo Province

Mulaudzi, Rudzani Grace January 2015 (has links)
Thesis (M.A. (Agricultural Extension)) -- University of Limpopo, 2015 / The aim of the study was to analyse the socio-economic factors affecting the gross margin of small-scale broiler producers in the Vhembe district and thereby determine their profitability and contribution towards the local economic development. The population comprised of small-scale broiler producers who reared between100 and 3200 birds in the Vhembe district. A total of 94 out of 311small-scale broiler producers were selected using a simple random- sampling procedure. Data on different socio-economic parameters was collected through personal interviews using a semi-structured questionnaire. Descriptive statistics was computed using FREQ COUNTS procedures to describe the characteristics of small-scale broiler producers. Gross margin analysis was used to calculate the profitability for small-scale broiler producers. The Multiple Linear Regression was used to estimate the influence of socio-economic factors influence on the gross margin of the small-scale broiler producers. Multiple Regression analysis indicated that small-scale broiler producers in the Vhembe district were making profit. Socio-economic variables such as age of the farmer, farming experience, flock size, training received by the farmer, market access and record keeping, educational level, household income and extension services were found to have positive correlation with the small-scale broiler producers‟ gross margin. To effectively address production constraints affecting gross margin of small-scale broiler producers, it is, therefore, fundamental to consider their socio-economic profiles.

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