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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.
121

Crude fibre digestion in broiler and indigenous Venda chickens

Ginindza, Muzi Mandla January 2020 (has links)
Thesis (Ph. D. (Animal Production)) -- University of Limpopo, 2020 / A study was conducted to determine the effect of dietary crude (CF) levels of (3, 4, 5 and 7 %) on feed intake, digestibility, growth rate, feed conversion ratio (FCR) and live weight of male Ross 308 broiler and indigenous Venda chickens aged 1 to 42 days. The study, also, determined the effect of dietary CF level on the gastrointestinal morphology and digesta pH of gut organs of male Ross 308 broiler and indigenous Venda chickens aged 42 days. Dietary CF levels affected (P<0.05) feed intake, growth rate and live weight of male Ross 308 broiler and Venda chickens aged 1 to 21 days. A dietary CF level of 3.9 % optimized feed intake, while 4.5 % dietary CF optimized growth rate and live weight in male Ross 308 broiler chickens. However, dietary CF levels of 4.4, 4.8, 5.9 and 4.7 % optimized feed intake, growth rate, FCR and live weight, respectively, of male Venda chickens aged 1 to 21 days. Therefore, dietary CF level for optimal productivity depended on the breed of the chicken and production parameter of interest. Higher dietary CF levels decreased (P<0.05) crude protein (CP), neutral detergent fibre (NDF) and acid detergent fibre (ADF) digestibility values in male Ross 308 broiler chickens. Dietary CF levels of 3.8, 3.7 and 4.1 % optimized dry matter (DM) digestibility, metabolizable energy (ME) intake and nitrogen retention, respectively, in male Ross 308 broiler chickens aged 14 to 21 days. Increased dietary CF level, also, decreased (P<0.05) NDF and ADF digestibility values in male Venda chickens aged 14 to 21 days. Dry matter and CP digestibility values, ME intake and nitrogen retention of Venda chickens were optimized at dietary CF levels of 3.5, 3.7, 3.3 and 4.1 %, respectively. Feed intake of male Ross 308 broiler chickens aged 22 to 42 days were affected (P<0.05) by dietary CF level; and it was optimized at a dietary CF level of 6.4 %. Increased dietary CF level resulted in poorer growth rate, FCR and live weight of male Ross 308 broiler chickens. However, dietary CF levels of 4.5, 5.8, 6.4 and 5.7 %, optimized feed intake, growth rate, FCR and live weight, respectively, of male Venda chickens aged 22 to 42 days. Dietary CF levels of 3.4, 4.4, 3.7 and 4.4 %, optimized DM, CP and NDF digestibility values, and nitrogen retention, respectively, in male Ross 308 broiler chickens. However, dietary CF levels of 5.1, 5.3, 4.9, 10.1 and 5.1 % optimized DM, CP, NDF and ADF digestibility values, and nitrogen retention, respectively, of male Venda chickens. Therefore, dietary CF level for v optimal response in the chickens depended on breed, age and production variable of interest. The GIT weight of male Ross 308 broiler chickens was optimized at a dietary CF level of 4.1 %. In increased dietary CF level in male Ross 308 broiler chickens increased gizzard weights and decreased small intestine weights (P<0.05). Dietary CF levels of 6.3, 5.9 and 8.0 % optimized GIT, gizzard and caecum weights, respectively, in male Venda chickens. The small intestine weight of male Venda chickens was not affected (P<0.05) by dietary CF level. Caecum weight of male Venda chickens increased (P<0.05) with higher dietary CF level. However, caecum weights of male Ross 308 broiler chickens were not affected (P>0.05) by dietary CF level. The GIT and small intestine lengths were affected (P<0.05) by dietary CF level in male Ross 308 broiler chickens. Dietary CF levels of 5.6 and 5.5 % optimized GIT and small intestine lengths, respectively. However, in male Venda chickens, GIT and small intestine lengths were not affected (P>0.05) by dietary CF level. Digesta pH of the proventriculus and gizzard were affected (P<0.05) by dietary CF level in male Ross 308 broiler and Venda chickens. Different dietary CF levels of 5.5 and 7.4 % optimized the proventriculus and gizzard digesta pH in male Ross 308 broiler chickens, respectively. However, dietary CF levels of 4.2 and 4.3 % optimized the proventriculus and gizzard digesta pH values, respectively, in male Venda chickens. The two breeds of chickens had similar digesta pH values of the crop, proventriculus, gizzard and large intestines. However, male Venda chickens had higher (P<0.05) small intestine digesta pH values than male Ross 308 broiler chickens aged 42 days. Caecum digesta pH values of Ross 308 broiler chickens were higher (P<0.05) than those of Venda chickens aged 42 days. The second study was conducted to determine the effect of sodium bicarbonate supplementation level in the drinking water on feed intake, digestibility, FCR, growth rate, gut organ weight, length and digesta pH of male Ross 308 broiler and Venda chickens aged 22 to 42 days. The study, also, determined the effect of sodium bicarbonate supplementation level in drinking water on types of bacterial species in crop and gizzard digesta, as well as its effect on meat quality of male Ross 308 broiler and indigenous Venda chickens. Increased sodium bicarbonate vi supplementation level increased (P<0.05) water pH. Supplementation levels of 8.9, 2.04, 2.97 and 2.97 g of sodium bicarbonate per litre of drinking water optimized water intake, feed intake, growth rate and live weight of male Ross 308 broiler chickens, respectively. In male Venda chickens, there was a strong and positive relationship between sodium bicarbonate supplementation level and water intake of Venda chickens. A single supplementation level of 3.8 g of sodium bicarbonate per litre of drinking water optimized growth and live weight of male Venda chickens. There was a negative relationship between sodium bicarbonate supplementation level in the drinking water and NDF digestibility of male Ross 308 broiler chickens. Supplementation levels of 2.63, 6.67 and 7.0 g of sodium bicarbonate per litre of drinking water optimized DM and CP digestibility values, and nitrogen retention, respectively, in male Ross 308 broiler chickens. However, supplementation levels of 3.2 and 4.52 g of sodium bicarbonate per litre of drinking water optimized DM and NDF digestibility values, respectively, in male Venda chickens. There were negative relationships between sodium bicarbonate supplementation level in the drinking water and CP digestibility and nitrogen retention of male Venda chickens. Supplementation levels of 5.7, 2.2, 3.8, 7.6 and 7.2 g of sodium bicarbonate per litre of drinking water optimized proventriculus, gizzard and small intestinal weights, and GIT and small intestines lengths, respectively, in male Ross 308 broiler chickens. However, a sodium bicarbonate supplementation level of 2.8 % optimized proventriculus weights of male Venda chickens; the other digestive organ weights and lengths of Venda chickens were not affected (P>0.05) by sodium bicarbonate supplementation level. Sodium bicarbonate supplementation in the drinking water affected bacterial species found in the crops and gizzards of the chickens. There were different bacterial species found in the crop and gizzard digesta of male Ross 308 broiler and Venda chickens. Meat colour (L*, a* and b*) of the breasts and thighs of both breeds of chickens were not affected (P>0.05) by sodium bicarbonate supplementation. However, the redness (a*) values of the breast meat of male indigenous Venda chickens were higher (P<0.05) than those of breast meat from male Ross 308 broiler chickens. Sodium bicarbonate supplementation level did not affect (P>0.05) breast meat tenderness, juiciness, flavour and overall acceptability values and meat pH of Ross 308 broiler chickens. Supplementation levels of 3.6, 3.2 and 4.7 g of vii sodium bicarbonate per litre of drinking water optimized meat juiciness, flavour and shear force of male Venda chickens, respectively. It was concluded that sodium bicarbonate supplementation in the drinking water affected growth, NDF digestibility and bacterial species composition of male Ross and Venda chickens. Sodium bicarbonate supplementation level for optimal response in chickens depended on the breed and production variables of interest. / VLIROUS
122

Methodology to evaluate the nutritive value of feedstuffs for poultry and swine

Ravindran, Velmurugu January 1982 (has links)
Six tropical feedstuffs were analyzed for proximate composition, Van Soest components, mineral contents and amino acid composition. The crude protein contents (dry basis) of cassava tuber meal, sesame oil meal, coconut oil meal, rubber seed meal, cassava leaf meal and sweet potato leaf meal were 2.9, 35.2, 21.8, 12.0, 20.2 and 10.4%, respectively. The corresponding values for acid detergent fiber were 5.0, 23.5, 29.4, 39.1, 35.0 and 46.4%, respectively. Cassava tuber meal contained 88.4% nitrogen-free extract, but was poor in minerals and amino acids. Sesame oil meal had a silica content of 12.2% possibly indicating adulteration with sand; it was rich in all the minerals, especially Ca (2.32%), Mg (.56%), P (1.04%) and Fe (.32%). Coconut oil meal contained high amounts of Na (852 ppm) and K (1.83%), whereas the Zn (249 ppm) and Mn (252 ppm) were higher in cassava leaf meal. With the possible exception of sesame oil meal, the sulphur amino acids are likely to be the most limiting when these feedstuffs are fed to livestock. True metabolizable energy (TME) values of cassava tuber meal, cassava leaf meal and sesame oil meal were determined using 24 adult Single Comb White Leghorn roosters. After 24 hours of fasting, six roosters were force-fed 25 g of each of these feedstuffs. Six roosters were fasted for another 48-hour period and served as negative controls. Excreta were collected for two consecutive 24-hour periods. Length of collection period had no effect on the TME of cassava tuber meal and sesame oil meal, indicating that a 24-hour collection period was adequate for these feedstuffs. A collection period of 48 hours or longer was, however, required for roosters force-fed cassava leaf meal. The mean TME values (dry basis) of cassava tuber meal, cassava leaf meal and sesame oil meal were determined to be 3.76 ± .06, 1.99 ± .28 and 2.42 ± .09 kcal/g, respectively. Three digestion trials, each involving 12 crossbred gilts averaging 35.2 kg body weight, were conducted to determine the effects of crude fiber and Virginiamycin on digesta rate of passate (RP) and nutritional parameters. Two levels (3.2 and 7.3%) of crude fiber and two levels (0 and 11 ppm) of Virginiamycin were used in a 2 x 2 factorial arrangement of treatments. All diets were isonitrogenous and isocaloric. RP was determined by noting the time required for a change in feces color following the addition of 0.5% chromic oxide to the diet. The high fiber diet had a faster (P<.001) RP and this was associated with depressions (P<.001) in the digestibility of dry matter (DM), energy (E), cell content, cell wall (CW), acid detergent fiber (ADF), hemicellulose, cellulose, lignin and ash. Virginiamycin supplementation slowed (P<.01) the RP of both low and high fiber diets, but improved (P<.10) the DM, E and CW digestibility of the high fiber diet only. Non-significant improvements (P<.15) in the digestibility of ADF and cellulose were also observed when Virginiamycin was supplemented to the high fiber diet. Fiber increased (P<.05) fecal nitrogen, whereas Virginiamycin supplementation decreased (P<.05) fecal nitrogen. Results suggest that Virginiamycin supplementation improved the energy utilization in a high fiber diet, but had little effect on a low fiber diet. A study was conducted, concurrent to the first total collection digestion trial, to evaluate the applicability of chromic oxide indicator method to estimate the digestibility of nutrients. Digestion coefficients derived from the indicator method were in close agreement with those determined by the conventional total collection method for the low fiber diet, but underestimate the values for the high fiber diet. / Master of Science
123

Effects of various male feeding regimens on reproduction in broiler breeders

Fontana, Eddy Alejandro 15 July 2010 (has links)
A study was conducted using commercial broiler breeders with the males fed a diet containing, either 120/0 or 140/0 protein and body weight maintained at either 900/0 or 1000/0 of that recommended by the primary breeder (fed separately), or allowed to eat from the female feeders (controls). Female feeders in the separately fed pens were equipped with especially designed grills, which denied access to the males. The male feeder in these pens was elevated so that females were denied access. Males fed separately (body weight 90% or 1000/0, and dietary protein 120/0 or 140/0) had a significantly higher percentage fertility (4.20/0) than males allowed to eat with the females. No differences in percentage fertility were found among the four separately fed groups. No differences were noted in percentage hatch of fertile eggs among any of the treatment groups. Males eating from the female feeders had significantly heavier body weights and testes weights at 65 weeks of age than breeder males in the separately fed, groups. Mean body weights were 3819g and 4773g at 35 weeks of age, and 4192g and 5443g at 65 weeks of age for males eating separately and eating with the females, respectively. Furthermore, males in the control group had significantly larger breast angle measurements when compared with the separately fed males. No differences were observed in foot scores and semen concentration among males in the various treatment groups. / Master of Science
124

Methodology for evaluating the digestibility and metabolizable energy of poultry feedstuffs

Blake, John Paul January 1986 (has links)
Determining the energy values of feed ingredients for poultry is of great concern, especially since production efficiency is associated with profit margins. Therefore, accurate, precise, and reproducible energy values for feed ingredients are of the utmost importance in formulating an economical diet. An important aspect in determining the apparent metabolizable energy (AME) of a feed ingredient is the procedure employed in the drying of excreta samples. During sample preparation, substantial grinding losses were incurred amounting to 3.5 to 5.2% of the dried sample weight. Also moisture uptake during sample grinding accounted for a 1.9 to 3.9% increase in sample weight. To properly account for such losses, freshly collected excreta samples should be weighed, oven-dried at 40 C, reweighed, allowed to equilibrate with atmospheric moisture, weighed, ground, reweighed, and stored in air-tight containers for subsequent analyses. From the oven-drying of feed and excreta samples at various temperatures, a linear decrease in sample weight occurred with increasing drying temperatures. When dried at 100 C or less, the energy content of feed and excreta samples remained unchanged, but increased significantly at higher temperatures. The nitrogen composition of feed and excreta samples exhibited a similar trend, but a significant loss of excreta nitrogen (2%) occurred at 100 C. The loss of excreta nitrogen at a temperature of 100 C is of relatively minor consequence in the determination of metabolizable dry matter, but is of major concern in nitrogen balance studies. Extraction of feed and excreta samples with N,N-dimethylformamide and titration with Karl Fischer reagent indicated that significant amounts of water were retained by samples dried at 40, 60, and 80 C. However, at temperatures of 100 C or greater, little water was retained but sample decomposition occurred. A drying temperature of 90 C or the Karl Fischer method may yield a more accurate value for the dry matter of feed or excreta. When seven roosters were subjected to a total collection method for five consecutive days, individual birds were better metabolizers of dry matter and energy than others. By either a voluntary intake method or by a total collection method, values for the nitrogen-corrected metabolizable energy of corn were similar. The total collection method proved to be more reliable since it provided the least amount of variation when <u>ad libitum</u> feed intake and total excreta output were measured over a period of several days. In past experiments, adding fats to a test diet at the expense of cerelose in amounts no greater than 20% of the diet to determine the metabolizable energy of the fat has been associated with a high degree of variability. From the force-feeding of fats at levels to 100%, the variation associated with the metabolizable energy value of a fat was greatly reduced. The methodology presented here provided reliable estimates and detected differences between the metabolizable energy of two feed-grade fats in comparison to previous methods. / Ph. D. / incomplete_metadata
125

Nutritional parameters associated with enteric Escherichia coli and rotavirus in poults

Schmidt, Gregory P. January 1983 (has links)
Experiments were conducted to investigate the effects of E. coli and rotavirus as causative agents in producing infectious stunting syndrome of poults. The syndrome, as it occurs commercially, was characterized in two experiments to produce decreased digestible dry matter and nitrogen as well as increased excreta nitrogen and gross energy content of affected poults. The effects of E. coli and rotavirus on the nutritional performance of poults were compared to the commercial syndrome by digestibility trials and assay of intestinal mucosaI enzyme activities. The strain of E. coli used in these experiments was isolated from the yolk sac of stunted poults. Inoculation of day-old poults was done orally in one experiment and via the yolk sac in another series of experiments. Experiments were designed in a factorial arrangement of E. coli inoculation and dietary protein level (28 vs. 22%). Oral administration of the pathogenic E. coli at a low dose (.1 ml of a 10⁻² dilution of a 24-hr culture) to day-old poults produced a significant increase in feed efficiency by 21 days of age for birds fed either 28 or 22°0 protein diets. In this case, E. coli apparently was established as part of the normal intestinal microflora of the turkey without producing a toxic response. Similar concentrations of E. coli (10⁻³ and 10⁻² dilutions) inoculated into the yolk sac of day-old poults resulted in significant mortality and morbidity. The lower dilution (10⁻³) produced the desired response of stunted poults without substantial mortality. Body weight gain and feed consumption were severely decreased by E. coli inoculation at both levels of protein (28 or 22%). The 28% protein diet alleviated the reduction in feed consumption for birds infected with the lower concentration of E. coli. The 10⁻² dilution caused substantial mortality and similar responses on body weight at both levels of protein. A malabsorption of nutrients accompanied E. coli infection in spite of reduced feed consumption as indicated by increased excreta nitrogen and gross energy content for all infected poults. In three experiments, rotavirus was orally inoculated into poults over 21 days of age previously fed either 28 or 22% protein diets. The response of rotavirus was variable in the three experiments, however, the low protein diet (22%) increased the poults susceptibility to rotavirus infection. Serum antibodies to rotavirus were detected in all poults tested prior to inoculation. Ubiquitous in nature, rotavirus appears to produce clinical signs of infection in combination with stress on the poults. Effects of rotavirus on digestibility parameters were inconclusive. In experiments with either rotavirus or E. coli, activities of intestinal mucosal enzymes were found to vary more between poults within a treatment than by any effect of the various treatments. / Ph. D.
126

Development of cassava (Manihot esculenta Crantz) leaf meal as an animal feed

Ravindran, Velmurugu January 1985 (has links)
Research was conducted in Sri Lanka to evaluate the feasibility of developing cassava (Manihot esculenta Crantz) leaf meal as an animal feed. In feeding trials with broilers, improvements in performance were observed at 10% inclusion of cassava leaf meal (CLM). High levels (20 and 30%) of CLM depressed gain, feed intake and feed per gain. Weights of spleen and liver (% of body weight) linearly increased with increasing levels of CLM. Carcass pigmentation values favored the CLM-based diets. Dietary additives (methionine, sodium thiosulfate or soybean oil plus methionine) improved the growth of broilers fed 20% CLM diet without, however, having any beneficial effect when added to the basal diet. Gain of broilers tended to decrease with increasing dietary levels of cyanide. Feeding trials with growing pigs showed that CLM can be included up to 26.7% level without any effect on performance. Gain and feed per gain were improved at 13.3% CLM level, whereas marked depressions were noted at 40% CLM level. Results of the balance trials indicated that cassava leaf protein is utilized more efficiently by the pigs, although the nutrients in CLM are not as digestible as those in coconut oil meal. The overall results suggest that bulkiness, low energy content, methionine deficiency and presence of anti-nutritional factors, are the major factors limiting the high level use of CLM in non-ruminant diets. Studies on the processing of CLM revealed that simple drying is sufficient to eliminate almost 90% of the initial cyanide level in the fresh cassava leaves. A combination of chopping and 3-day wilting prior to drying proved most effective in lowering the cyanide level of CLM. Field trials conducted with a short-age cassava variety, MU 22, demonstrated that it is possible to increase cassava leaf dry matter yields by defoliating once during the growing season and to produce within 86% of the normal yield of roots. Two defoliations during the growing season depressed the root crop by more than half. / Ph. D.
127

Central control of food intake in the domestic fowl

Skewes, Peter Alan January 1985 (has links)
This study was initiated to determine if factors exist in the blood or cerebrospinal fluid (CSF) of the domestic fowl that act upon the central nervous system to control food intake. Plasma collected from free-feeding and 24-hour fasted leghorn cockerels was lyophilized, reconstituted to 2, 4, or 5 times the original concentration, and injected, via a stereotaxically implanted 23 gauge stainless steel guide cannula, into the lateral ventricle of free-feeding leghorn cockerels. Food intake was significantly reduced following injection of 2, 4, and 5 times normal concentration of plasma from free-feeding birds. Plasma from fasted birds did not alter food intake regardless of concentration, but did significantly reduce water intake when concentrated to five times normal. A similar study was conducted with fractions of plasma of different molecular weight ranges. Plasma collected from free-feeding cockerels was partitioned by gel filtration into the following molecular weight fractions: >5000 molecular weight, <5000 molecular weight, 1500-5000 molecular weight, and <1500 molecular weight. The fractions were lyophilized and reconstituted to four times the original concentration and injected into the lateral ventricle of free-feeding leghorn cockerels. Food intake was significantly decreased by the <5000 and <1500 molecular weight fractions, whereas water intake was not affected. The 1500-5000 molecular weight fraction and the fraction above 5000 did not affect food or water intake. To determine if this food intake inhibiting factor existed in the cerebrospinal fluid (CSF) of the domestic fowl, CSF was collected from free-feeding and 24-hour fasted broilers and injected into the lateral ventricle of leghorn and broiler cockerels. Food intake was not affected by either the normal or four-times normal concentration of CSF collected from free-feeding or 24-hour fasted broilers. Water intake was significantly increased in the leghorn and broiler birds receiving the four times normal concentration of CSF collected from 24-hour fasted birds, but was not affected in the birds receiving CSF collected from the free-feeding donors. It appears, therefore, that a food intake inhibiting factor exists in the plasma of the free-feeding domestic fowl that does not exist in the CSF. / Ph. D.
128

The effects of a multiple-enzyme combination in maize-soya diets for broiler chickens

Fourie, Juan-Louis 03 1900 (has links)
Thesis (MscAgric (Animal Sciences))--University of Stellenbosch, 2007. / The effect of a multiple-enzyme combination in mash and pelleted vegetarian maize-soya diets for broilers was evaluated in terms of apparent excreta- and ileal nitrogen- and amino acid digestibility and production performance. Two separate digestibility trials and one performance trial were conducted. For Trial 1, the apparent nitrogen (N) - and amino acid (AA) digestibility was determined by the collection of the excreta (total collection method) and in Trial 2 from digesta collected at the terminal ileum (ileal digestibility method). Production performance was also recorded in Trial 1. In Trial 3, the effect of the multipleenzyme combination in potentially improving performance of broilers in commercial conditions was evaluated. Broilers were fed a balanced- and low apparent energy (AME) vegetarian maize-soya diet with the addition of the multiple-enzyme combination. The addition of enzymes improved the apparent excreta- and ileal N digestibility of the mash diets during the period 14-21 d, and the ileal N-digestibility of the pelleted diets at 28 and 35 d of age. Conflicting results with regard to apparent excreta- and ileal AA digestibility were found. By both methods the digestibilities of threonine (Thr), methionine (Met) and phenylalanine (Phe) (14-21 d) and Cys (22-28 d and 29-35 d) were improved by the addition of the enzyme combination to the mash diets. Over the entire experimental period (14-35 d) the ileal digestibilities of histidine (His), Cys and leucine (Leu)of the mash diets were improved by 0.2 %, 0.2 % and 1.9 % respectively, following enzyme addition. By both methods the digestibilities of Thr, arginine (Arg), Met, Cys, Phe and Leu (14-21 d), serine (Ser), Arg, glutamic acid (Glu), Val, His, aspartic acid (Asp), lysine (Lys), proline (Pro), Met, tyrosine (Tyr), Phe and Leu (22-28 d), and Pro (29-35 d) were improved by the combination of enzymes and pelleting. For the entire experimental period (21-35 d), the ileal digestibilities of Ser, His, Lys, Met, Tyr, Cys, Phe and Leu was improved by the combination of enzymes and pelleting, indicating enzymatic activity was not destroyed by cold pelleting at 60 - 80º. The improvements in apparent nitrogen- and AA digestibilities were, in most cases, not reflected in production performance, although the combination of enzymes and pelleting resulted in improved body weight gain (BWG) for the first two weeks of chicks life and significantly improved the feed conversion ratio (FCR) during the second week of the chicks’ life. The effect of the multiple-enzyme combination on the production performance of broilers on a low AME- and commercial diet was mostly non-significant except for a significantly lower feed iii intake of the balanced diet for the fourth and fifth week of chick’s life following enzyme addition. A financial calculation showed, however, that the enzyme combination might increase profitability of a nutritionally balanced vegetarian maize-soya diet for broilers.
129

The evaluation of larvae of Musca domestica (common house fly) as protein source for broiler production

Pretorius, Q. 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: The objective of this study was to evaluate the use of Musca domestica (common house fly) larvae meal, as protein source, for broiler production. This was done by investigating the nutritive value of house fly larvae meal together with its total tract digestibility, potential toxicity and carcass characteristics of the broilers supplemented with house fly larvae meal. The proximate analysis of house fly larvae meal show that it contained, on a dry matter basis, a gross energy value of 20.10 MJ/kg, 60.38% crude protein, 14.08% crude fat and 10.68% ash and that the house fly pupae contained a gross energy of 20.42 MJ/kg, 76.23% crude protein, 14.39% crude fat and 7.73% ash. House fly pupae meal had the closest match of amino acid profile when compared with the ideal amino acid profile required by broilers and it has arginine relative to the lysine content closer to the ideal amino acid profile than the house fly larvae meal. The essential fatty acid, linoleic acid, was found at levels of 26.25 and 36.27% of the total fats for the house fly larvae and pupae meal respectively. House fly larvae meal supplementation did not induce gizzard erosion or showed toxicity (regarding the gastro intestinal tract, immune system and organ stress) in broilers. Results revealed that house fly pupae meal had higher total tract digestibilities for most nutrients than of the house fly larvae meal. House fly larvae meal had a crude protein total tract digestibility of 69% and that of pupae meal was 79%. Both larvae and pupae meal had high amino acid total tract digestibilities of all the amino acids analysed. The house fly larvae and pupae meal had an apparent metabolizable energy (AME) value of 14.23MJ/kg and 15.15MJ/kg respectively. The larvae meal total tract crude fat and crude fibre digestibilities were 94% and 62% respectively. The pupae meal total tract crude fat and crude fibre digestibilities were 98% and 58% respectively. House fly larvae meal supplementation in a three phase feeding system significantly increased average broiler live weights at slaughter, total feed intake, cumulative feed intake as well as average daily gain (ADG) when compared to commercial maize: soya oil cake meal diet. In direct comparison of larvae inclusion levels with fishmeal in isonitrogenous and isoenergetic diet, no significant differences were observed between a 10% house fly larvae and a 10% fish meal diets regarding performance characteristic. The 25% house fly larvae meal diet yielded significantly better average broiler live weights at slaughter, total feed intake, cumulative feed intake (from the second week until slaughter) as well as average daily gain when compared to the 25% fish meal diet in the growth phases. Carcass characteristics of the 10% larvae, 10% fishmeal and commercial diets were compared. Chicks that received either the 10% house fly larvae meal or 10% fish meal supplementation produced significantly heavier carcasses and breast muscle portions than the chicks that received the commercial maize: soya oil cake meal. No treatment differences were found regarding breast and thigh muscle colour or pH. This study showed that house fly larvae meal can be regarded as a safe protein source that can be used to replace other protein sources and that has the ability to promote broiler performance without having any detrimental effects on carcass characteristics. / AFRIKAANSE OPSOMMING: Die evaluasie van Musca domestica (gewone huisvlieg) larwe meel as ‘n proteien bron vir braaikuiken produksie Die doel van die studie was om die effek van Musca domestica (gewone huisvlieg) larwe meel, as ‘n protein bron, in braaikuikens te evalueer. Dit was gedoen deur die nutrient waarde van huisvlieg larwe meel saam met die totale spysvertering verteerbaarheid, moontlike toksiesiteit en karkas-eienskappe van braai kuikens te evalueer. Laboratoruim analiese toon dat huisvlieg larwe meel 20.10 MJ/kg bruto energie, 60.38% ru- protein, 14.08% ru- vet en 10.68% as bevat en huisvlieg papie meel 20.42 MJ/kg bruto energie, 76.23% ru- protein, 14.39% ru- vet en 7.73% as bevat. Huisvlieg papie meel stem die meeste ooreen met die idiale amino suur profiel soos wat benodig word deur braaikuikens en dit het ‘n arginien tot lisien verhouding wat die meeste ooreenstem met die idiale amino suur profiel in vergelyking met huis vlieg larwe meel. Die essensiele vet suur, linolien suur, was geanaliseer teen vlakke van 26.25- en 36.27% van die totale vette onderskeidelik vir huisvlieg larwe- en papie meel. Huisvlieg larwe meel vervanging het nie spiermaag erosie of enige ander toksiese effekte te veroorsaak nie. Resultate het getoon dat huisvlieg papie meel, in vergelyking met larwe meel, het ‘n hoër totale spysvertering verteerbaarheid vir meeste van die nutrient. Die huisvlieg larwe meel het ‘n totale ru- protein spysvertering verteerbaarheid van 69% en die van papie meel van 79%. Beide larwe en papie meel het hoë amino suur spysvertering verteerbaarheid. Larwe meel en papie meel het skynbare metaboliseerbare energie waardes van 14.23MJ/kg en 15.15%MJ/kg onderskeidelik. Die larwe meel het ‘n ru-vet en ru- vesel spysvertering verteerbaarheid van 94% en 62% onderskeidelik, waar die papies ‘n ru-vet en ru- vesel spysvertering verteerbaarheid van onderskeidelik 98% en 58% het. Huisvlieg larwe meel vervanging in ‘n drie fase voer stelsel het getoon om die gemiddelde braaikuiken lewende gewigte by slag, totale voer iname, sowel as die gemiddelde daaglikse toename te verhoog waneer dit vergelyk word met ‘n kommersiele mielie- soya olie koek dieet. Geen mekwaardige verskille was waargeneem toe die 10% larwe meel dieet direk met die 10% vismeel diet vergelyk was rakende enige produksie einskappe gemeet nie. Die 25% larwe meel dieet het merkwaardig beter gemiddelde braaikuiken lewende gewigte by slag, totale voer iname, sowel as die gemiddelde daaglikse toename getoon wanneer vergelyk word met die 25% vismeel dieet gedurende die verskeie groei fases. Karkas eienskappe van die 10% larwe meel, 10% vismeel en die kommersiele diete was gevergelyk. Kuikens wat 10% larwe meel en 10% vismeel in die diete ontvang het, het swaarder karkasse gelewer met swaarder borsie massas wanneer vergelyk word met die kommersiele mielie- soya olie koek dieet. Geen behandelings verskille was gevind rakende die borsie- en dy spier kleure of pH nie. Die studie toon dat huisvlieg larwe meel as ‘n veillige protein bron kan beskou word, wat gebruik kan word om ander protein bronne te vervang. Huisvlieg larwe meel het ook die vermoë om braaikuiken produksie te verhoog sonder om enige negitiewe effekte rakende die karkas eienskappe te toon nie.
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Effect of supplementing diets with effective microorganisms on intake, growth and carcass characteristics of ross 308 broiler chickens

Mafiri, Matseko Nkele January 2014 (has links)
Thesis (M.Sc. (Animal Production)) -- University of Limpopo, 2014 / Two experiments were conducted to determine the effects of supplementing diets with effective microorganisms on intake, growth and carcass characteristics of Ross 308 broiler chickens. The first experiment determined the effect of supplementing diets with effective microorganisms on performance of unsexed Ross 308 broiler chickens aged one to three weeks. Two hundred unsexed day-old chicks were randomly assigned to five treatments with four replications, each replication having ten birds. A complete randomized design was used. The chickens were fed a grower diet supplemented with 0 (EM0), 30 (EM30), 50 (EM50), 70 (EM70) or 100 (EM100) ml of effective microorganisms per litre of water. Effective microorganism supplementation did not improve (P>0.05) diet and metabolisable energy intakes of the chickens. Effective microorganism supplementation reduced (P<0.05) growth rate and live weight of the chickens. Poorer (P<0.05) feed conversion ratios were observed in chickens supplemented with effective microorganisms. However, effective microorganism supplementation improved (P<0.05) crude protein retention of the chickens. Supplementation with effective microorganisms reduced (P<0.05) mortality rate of the chickens from 10 to 0 %. The second experiment determined the effect of supplementing diets with effective microorganisms on performance of male Ross 308 broiler chickens aged 22 to 42 days. The chickens were randomly allocated to five treatments with four replications, each replication having 10 birds. The chickens aged 21 days, weighing 474 ± 2g, were allocated to the treatments in a complete randomized design. The chickens were fed a grower diet supplemented with 0 (EMM0), 30 (EMM30), 50 (EMM50, 70 (EMM70) or 100 (EMM100) ml of effective microorganisms per litre of water. Effective microorganism supplementation did not improve (P>0.05) intake, DM digestibility, metabolisable energy, feed conversion ratio, fat pad weight and meat sensory attributes of the chickens. Effective microorganism supplementation reduced (P<0.05) growth rate, live weight and carcass weight of the chickens. However, effective microorganism supplementation improved (P<0.05) crude protein retention and crude protein content of meat of the chickens. Supplementation with effective microorganisms reduced (P<0.05) mortality of the chickens from 5 to 0 %. v It is concluded that effective microorganism supplementation to the diets of Ross 308 broiler chickens reduced growth rate and live weight of the chickens. However, effective microorganism supplementation improved crude protein retention and crude protein content of the meat of broiler chickens. Supplementation with effective microorganisms reduced mortality of the chickens to zero.

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