This study was conducted to examine the potential of plastic slats as flooring material for maintenance of broiler breeders. Although plastic slats are more expensive than wood slats, plastic slats are more durable and easier to clean. Wood and plastic slats were tested as full and partial flooring to determine the ideal proportion of slats for broiler breeder floors. Space allotment was 2040 cm²/bird on all floor treatments. . Arbor Acres broiler breeders, one of the more common strains in British Columbia, were raised to 58 weeks of age to monitor the influence of slat material and slat coverage on egg production and progeny growth over one production cycle. Since the pens were not set up to determine the number of eggs lost through slats, "egg production" values were actually egg recovery values. Over-all egg recovery was significantly higher on partial wood (PWS) and partial plastic slats (PPS) than on either of the full slat treatments. Breeders on full wood slats (FWS) had higher over-all egg production than those on full plastic slats (FPS). Differences were significant for three biweekly periods, but slats did not influence the over-all incidence of floor eggs and cracked floor eggs. The incidence of cracked nest eggs was significantly higher in FWS and FPS than in PWS and PPS pens during four lay periods and overall. The proportion of non-cracked nest eggs, which was taken as an approximation of the proportion of settable eggs, was higher for partial slat pens than full slat pens, and FWS pens had a higher proportion of non-cracked nest eggs than FPS pens. To monitor fertility and hatchability, eggs were incubated at 37, 42, 46, 50 and 56 weeks of breeder age. Fertility, hatchability of total eggs set and hatchability of fertile eggs was not affected by type of slats. Progeny from the hatch at 37, 46 and 56 week of breeder age were grown in Petersime battery cages to three weeks of age. The progeny of breeders on FPS had lower first week weight gain than the other progeny groups due to moisture loss when 7 FPS progeny were lost during the second growth trial. Weekly and over-all feed conversion of progeny was not affected by types of slats used by parents. The 56th week progeny were grown in Petersime battery cages to market age (six weeks). PWS and FPS progeny had higher third week weight gain than PPS progeny. During the sixth week, FWS and PWS progeny had higher weight gain than FPS and PPS progeny. The sixth week feed conversion of FPS progeny was higher than that of the other three progeny groups. No other differences were seen. As long as slats were used as partial flooring, there were no differences in egg production on wood or plastic slats. The proportion of "settable" eggs, fertility, and hatchability of eggs of plastic slat breeders were comparable with that of wood slat breeders regardless of slat coverage. There were significant differences in the 3-week growth of 37th, 46th and 56th week progeny and the 6-week growth of 56th week progeny on the different slat types, but the differences were not due to slat treatments. There was no interaction between breeder age and slat material, therefore the influence of slat material on egg production and progeny growth did not vary with breeder age. Although egg recovery and the number of settable eggs were lower for FPS breeders, breeders on plastic slats performed as well as those on wood slats in the present study. / Land and Food Systems, Faculty of / Graduate

Call number: LD2668 .T4 1949 E15 / Master of Science

Over the last decade, food processing has become one of the greatest energy converting stages of the food production supply chain. The interdependency of food, water, and energy leads to a need for more water efficient and energy effective ways to produce food. These studies focus on poultry chilling, primarily comparing the potential options of media that could be used during the poultry chilling sub-process. The conventional poultry chilling approach typically involves the immersion of chicken within chilled water in order to quickly decrease the chicken temperature, thus hindering the growth of bacteria. This research is an initial investigation of ice slurry as an energy and water efficient, pathogen reducing, and financially feasible chiller medium in poultry processing. The financial feasibility and electrical energy demand of using ice slurry were explored in a techno-economic model in HOMER Energy, which is a micro-grid design and optimization software. The thermal cooling capacity of ice slurry and fluidity of the solution allows for generation and storage to occur during low electricity cost hours and an application during high electricity cost hours, thus creating savings in electricity costs associated with poultry chilling. During the poultry chilling experimentation, chickens were spiked with Salmonella as temperature probes measured their core body temperature throughout their immersion within the different media. Greater pathogen reductions, faster cooling times, and less water consumption compared to chilled water promotes ice slurry as an alternate medium in the poultry processing industry.

Thesis (MPhil)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: The study investigated the performance of broiler production III two enterprises around Gaborone. The main emphasis was on performance and feed efficiency of four major production parameters, which include feed intake (FI), age at slaughter, body weight (BW) and feed conversion ratio (FeR). The averages for slaughter age, BW (live weight), FI and FeR for the two enterprises combined were 39.6 days, 1.8 kg, 3.41 kglbird and 1.96, respectively. For the entire rearing period the average performance efficiency factor for the two enterprises was 224. The results of the current study showed that age at slaughter, BW, cumulative FI, FeR and mortality in the two farms declined significantly (P<O.OOI) over time. These improvements in performance may be ascribable to the genetic improvements of the broiler bird for fast growth, improved nutritional status as well as efficiency in management on the part of producers. / AFRIKAANSE OPSOMMING: Die studie ondersoek die vordering van braaikuiken produksie in twee ondernemings in die omgewing van Gabarone. Die klem was op die prestasie en voer doeltreffendheid van vier groot produksie parameters. Die parameters sluit in; voerinname (VI), ouderdom by slag, liggaamsmassa (LM), en voeromsettings verhouding (VOV). Die gekombineerde gemiddeldes vir die twee ondernemings vir slagouderdom, LM (lewende massa), VI en VOV was onderskeidelik 39.6 dae, 1.8 kg, 3.41 kg/voël en 1.96. Die gemiddelde prestasie doeltreffendheidsfaktor vir die twee ondernemings, vir die hele groei periode, was 224. Die resultate van die studie het daarop gedui dat ouderdom by slag, LM, kumulatiewe VI, VOV en mortaliteite aansienlik afgeneem (P<O.OOI) het oor tyd. Hierdie verbeteringe in vordering kan toegeskryf word aan die genetiese verbeteringe van die braaikuiken voël vir vinnige groei, verbeterde voedingstatus, sowel as doeltreffendheid in bestuur vanaf die produseerders.

published_or_final_version / abstract / Zoology / Master / Master of Philosophy

In broiler operations, various health problems develop during the final two weeks of the growing period, resulting in increased mortality and condemnation losses. At this stage, sickly birds were found to be systemically infected by various bacteria regardless of varied clinical signs. The main objective of the present study was to determine the prevalence and nature of systemic bacterial infections in unthrifty commercial broiler chickens and to establish a reproducible infection model in the laboratory. Thirty-one unthrifty 6-week-old broilers were obtained from three farms, and bacterial isolations were conducted on blood, liver, and hock joint. Bacteria were isolated from 87, 90, and 71% of the blood, liver and hock joint samples, respectively. Mean bacterial counts (log������ CFU/ml or g) of the blood and liver were 2.15 and 2.93, respectively. Among 132 bacterial isolates, major species were; Staphylococcus (60%), Corynebacterium (18%), Escherichia coli (5%), and Stomatococcus (4%). Among 79 Staphylococcus isolates, 77 were coagulase-negative. Major species of staphylococci were; S. lentus (19%), S. simulans (18%), S. cohnii (13%), S. gallinarum (10%) and S. captis (7%). In addition, 6 species of gram-positive and 5 species of gram-negative organisms were isolated. Apparently systemic infections were not caused by predominant pathogenic bacterial species, and adequately described as mixed infections. However, there were some significant relationships between isolated bacterial species and sampling sites, suggesting that certain organisms were abundant in the environment of a particular poultry house. These results indicate that systemic infections in market age broilers are caused by mixed bacterial species and suggest that they are caused by suppressed host antibacterial systems rather than pathogenic factors of microorganisms. Antibiotic susceptibility results showed 100% susceptibility of staphylococcal isolates (n=69) against vancomycin and enrofloxacin. Of these coagulase negative staphylococci showed 19% and 73% resistance against methicillin and penicillin G, respectively. There was also heterogeneity in antibiogram profiles within species of coagulase-negative staphylococci. Pathogenicity of representative field isolates from the above described study was tested in 5-day-old embryonated eggs and in 3- week-old broiler chicks. Consistent lethality was demonstrated with S. aureus in embryos. Staphylococcus intermedius or S. lentus demonstrated some pathogenicity, while S. gallinarum or Corynebacterium were non-pathogenic in embryos. In 3-week-old broilers, however, only S. aureus caused septicemia and death; other bacterial species mentioned above caused neither clinical signs of acute or chronic staphylococcosis nor mortality. / Graduation date: 1998

Seven experiments were carried out to investigate the involvement of carbohydrate and lipid metabolism on the incidence of Sudden Death Syndrome (SDS) in broiler chickens. Hepatic arachidonate level decreased after 1 h postmortem. The decreased level of hepatic arachidonate previously observed in SDS birds was, therefore, associated with the post-mortem aging. Broiler chickens fed diets high in glucose monohydrate (cerelose) were more susceptible to SDS mortality than broilers fed diets high in corn starch or corn-soy. Feeding broilers a high cerelose diet increased the levels of plasma calcium, total protein, triacylglycerol, and uric acid compared to broilers fed corn starch diet. Broilers fed cerelose diet also showed the higher incidence of leg abnormality than broilers fed corn starch or corn-soy diets. Daily intraperitoneal injection with 0.25 ml of L(+) lactic acid solution (100 mg lactic acid/ml) to broilers over a 7-d period failed to reproduce the SDS incidence, whereas intravenous injection of 40% lactic acid solution (200 mg lactic acid/kg body weight) resulted in 100% incidence of SDS-type mortality. No SDS-type mortality was observed with the intravenous injection of 40% sodium lactate solution (200 mg sodium lactate/kg body weight). Disturbance of physiological acid-base balance might be a factor in the SDS-type mortality. Suboptimal thiamin level in broilers fed cerelose diets was observed. Thiamin supplementation to cerelose diet improved the thiamin status of the broilers. Mortality due to SDS was decreased when thiamin hydrochloride was supplemented to cerelose diet at the level of 0.6 and 2.8 mg thiamin hydrochloride/kg diet, respectively. Thiamin supplementation, however, did not change the liver pyruvate dehydrogenase activity and the proportion of pyruvate dehydrogenase in the active form. Disturbance of acid-base balance was postulated to be associated with the incidence of SDS. Other genetic, nutritional, and environmental factors are likely to modify the incidence by affecting the acid-base status of the chicken. / Graduation date: 1993

The objectives in these four experiments were to observe the effectiveness of sodium bisulfate and clinoptilolite and different methods of application of sodium bisulfate, ferrous sulfate heptahydrate and Micro Aide® on atmospheric ammonia level in the broiler house and on broiler performance. The first experiment was conducted to determine the optimum effective level of the litter application of sodium bisulfate. Atmospheric ammonia at 4 weeks and litter moisture at 3 weeks treated-pens were significantly lower in sodium bisulfate (488 g/m²) than in the untreated control pens. However, broiler performance was not significantly affected with any treatment. Litter application of sodium bisulfate at 244 g/m² and 488 g/m² were comparable and better than the 122 g/m² and untreated control. In Experiments 2 and 3 comparisons of litter chemical treatments of liquid Micro Aid® (8.75 ml/L H₂O) applied at 0, 2, 4,and 6 weeks; granular Micro Aid® (0.5 mg/g of feed) fed continuously throughout the experiment, and litter application of ferrous sulfate (732 g/m²); clinoptilolite (2443 g/m²), sodium bisulfate (244 g/m²) and ferrous sulfate (732 g/m²) were made for 7 week periods. Ferrous sulfate-treated pens (732 g/m²) had significantly lower litter pH at 2, 4 and 6 weeks than untreated control and significantly lower atmospheric ammonia levels at 3 and 6 weeks than the clinoptilolite (2443 g/m²), sodium bisulfate (244 g/m²) and untreated control in the other experiment. In the fourth experiment, sodium bisulfate was applied twice (244 g/m²/application) at 0 and 4 weeks, sodium bisulfate applied once (488 g/m²) and ferrous sulfate applied once (732 g/m²) prior to the experiment. At 4 weeks mean body weights and feed conversion were significantly better with one sodium bisulfate application than the untreated control. At 7 weeks feed conversion (P<0.08) and male body weights (P<0.1) were slightly better in one sodium bisulfate application than in the untreated control while mortality was significantly lower in the untreated control pens. Most mortality occurred after 4 weeks and were due primarily to Sudden Death Syndrome. Atmospheric ammonia levels at 0, 1, 2, 3 and 4, weeks and litter pH levels at 0, 1, 2, 3, and 4 weeks were significantly lower in pens with one application of sodium bisulfate than in pens untreated. Litter application of sodium bisulfate once (488 g/m²) seemed to be the best litter treatment in reducing atmospheric ammonia. / Graduation date: 1991

Most of the feed required for poultry production in the Republic of Yemen is imported from Europe. Sometimes, feed shipments arrive later due to lack of hard currencies to pay for the feed or to pay the freight charges. Yemeni broiler producers in such cases feed their birds a single feed ingredient or a mixture of ingredients until feed arrives. Five experiments were conducted to simulate feed shortage situations. As a single ingredient, barley is the grain of choice in case of feed shortages. When broilers were switched to corn-soy after the single ingredient diets, the compensatory growth was correlated with the severity of reduced growth. Feeding diets with a mixture of faba beans + sorghum grain with or without 7% herring meal for 21 and 49 days, respectively, reduced significantly (P<.05) mean body weight, total feed consumed, feed efficiency and apparent protein efficiency ratio. Feeding wheat bran at 10-15% with adjustment for protein and energy from day-old to 49 days of age resulted in significantly (P<.05) improved mean body weights compared to the control broilers. Increasing wheat bran levels further gradually reduced body weight and feed consumption. Abdominal fat increased significantly (P<.05) when wheat bran inclusion exceeded 20 percent. Cellulase supplementation did not show any significant interaction with wheat bran in all the measured parameters. Supplementing protease to wheat bran diets significantly (P<.05) reduced mean body weight, feed consumption and the feed conversion in broilers. These dramatic effects were proportionally ameliorated by increasing the levels of wheat bran. / Graduation date: 1991

Thesis (M.S.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references.