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Culling the Non-Producing HenKenney, Francis R. 11 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
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Effects of early rearing environment on learning ability and behavior in laying hens /Morris, Hannah M. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 95-110). Also available on the World Wide Web.
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The relation between preference and demand for litter substrates in the domestic henHarris, Aimee Rebecca January 2006 (has links)
Six hen's preferences between 5-min access to each of two litter substrates, sand and sawdust, were measured using dependent concurrent VI 60 s VI 60 s schedules of reinforcement. The obtained preferences were small and idiosyncratic. Demand functions were generated separately for each of the two substrates by requiring the hens to perform under increasing FR schedules. The demand functions were disorderly, some were linear, some were of mixed elasticity, and others curved upwards. No clear relation between the individual hens' preference and demand measures was found. The overall response rates, running response rates and average post-reinforcement pause durations were atypical compared to previous demand research, possibly due to low levels of reinforcer collection, but were similar for individual subjects in both demand conditions. During the demand assessment, dustbathing took place in a similar proportion of reinforcers for each substrate. During the preference assessment, a greater proportion of dustbathing took place during sand reinforcers. Individual hens did not consistently dustbathe more in their preferred substrate. It was argued that the inconclusive results were a product of the substrates used. The atypical demand functions, response rates and average PRP durations may have been due to behaviour that was not schedule related occurring during key time (i.e., the subjects may have been continuing a dustbathing bout). It is possible, that the two substrates were too similar, and thus the subjects did not have a clear preference for one over the other. In future research preference should be assessed prior to demand, to ensure a clear preference can be obtained, with reinforcers that are qualitatively more different than those used in the present experiment.
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High fiber low energy diet for molt induction in laying hens: the impact of alfalfa on physiology, immunology and behaviorDunkley, Claudia Sharene 15 May 2009 (has links)
Feed withdrawal is commonly used by commercial egg producers to induce molt and stimulate multiple egg-laying cycles in their flocks. However, the practice can compromise the welfare of the birds by elevating stress, suppressing the immune response and causing abnormal behavior. An alternate molt diet was examined using alfalfa diets, and a series of experiments were conducted to evaluate the physiological, immunological and behavioral responses of laying hens fed these diets. We assessed the changes in the levels of blood plasma metabolites after hens were challenged with 106 colony forming units of Salmonella Enteritidis (SE). Hens fed alfalfa diets displayed similar (P ≥ 0.05) levels of cholesterol, glucose, and total protein when compared to full-fed hens. Reduced levels (P ≤ 0.05) of triglycerides were observed in the alfalfa fed and feed withdrawal hens when compared to the full-fed hens. The immune responses of SE challenged laying hens fed alfalfa diets showed similar (P ≥ 0.05) heterophil to lymphocyte ratios (H: L) to full-fed hens whereas the feed withdrawal hens displayed elevated (P ≤ 0.05) H: L ratios. The feed withdrawal hens displayed reduced (P ≤ 0.05) levels of serum IgY early in the trial when compared to the alfalfa and full-fed hens. The alfalfa fed hens displayed lower levels of acid α glycol protein than the feed withdrawal hens and higher levels than the full-fed early during the trial but returned to levels that were similar (P ≥ 0.05) to the full-fed hens. The hens fed alfalfa diets displayed elevated non-nutritive pecking behavior early in the trial however, this behavior declined to levels similar (P ≥ 0.05) to the full-fed hens by the end of the trial. No differences in aggressive behavior were observed between the alfalfa fed hens and the full-fed hens. Hafnium chloride did not effectively mark the alfalfa diet; however, it can be used to track the passage of corn-soy layer ration. This research suggests that the application of alfalfa as an alternative molt diet can be effective in reducing potentially harmful effects which are usually associated with feed withdrawal.
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High fiber low energy diet for molt induction in laying hens: the impact of alfalfa on physiology, immunology and behaviorDunkley, Claudia Sharene 15 May 2009 (has links)
Feed withdrawal is commonly used by commercial egg producers to induce molt and stimulate multiple egg-laying cycles in their flocks. However, the practice can compromise the welfare of the birds by elevating stress, suppressing the immune response and causing abnormal behavior. An alternate molt diet was examined using alfalfa diets, and a series of experiments were conducted to evaluate the physiological, immunological and behavioral responses of laying hens fed these diets. We assessed the changes in the levels of blood plasma metabolites after hens were challenged with 106 colony forming units of Salmonella Enteritidis (SE). Hens fed alfalfa diets displayed similar (P ≥ 0.05) levels of cholesterol, glucose, and total protein when compared to full-fed hens. Reduced levels (P ≤ 0.05) of triglycerides were observed in the alfalfa fed and feed withdrawal hens when compared to the full-fed hens. The immune responses of SE challenged laying hens fed alfalfa diets showed similar (P ≥ 0.05) heterophil to lymphocyte ratios (H: L) to full-fed hens whereas the feed withdrawal hens displayed elevated (P ≤ 0.05) H: L ratios. The feed withdrawal hens displayed reduced (P ≤ 0.05) levels of serum IgY early in the trial when compared to the alfalfa and full-fed hens. The alfalfa fed hens displayed lower levels of acid α glycol protein than the feed withdrawal hens and higher levels than the full-fed early during the trial but returned to levels that were similar (P ≥ 0.05) to the full-fed hens. The hens fed alfalfa diets displayed elevated non-nutritive pecking behavior early in the trial however, this behavior declined to levels similar (P ≥ 0.05) to the full-fed hens by the end of the trial. No differences in aggressive behavior were observed between the alfalfa fed hens and the full-fed hens. Hafnium chloride did not effectively mark the alfalfa diet; however, it can be used to track the passage of corn-soy layer ration. This research suggests that the application of alfalfa as an alternative molt diet can be effective in reducing potentially harmful effects which are usually associated with feed withdrawal.
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Spontaneously occurring fibroid tumors of the laying hen oviductDoernte, Amy Lynn, January 2006 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.
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Quantification of Soy Isoflavones in Commercial Eggs and Their Transfer from Poultry Feed into Eggs and TissuesVargas Galdos, Dante Miguel Marcial 27 August 2009 (has links)
No description available.
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Effects of zinc on Salmonella in the layer house environments and laying hens, and the ability of zinc to induce molt in laying hensPark, Shinyoung 17 February 2005 (has links)
There is increasing interest in developing methods to detect and identify Salmonella, to eliminate or reduce the risk of contamination of shell eggs, and to retain the economic advantages of induced molting without increasing the risk of Salmonella enteritidis infection. S. enteritidis and S. typhimurium are the most common serotypes among 2449 known serotypes of the Salmonella, and are the causes of most egg- related foodborne salmonellosis in humans in the U. S. These two species are also responsible for environmental contamination and the incidence of infections.
Therefore, this study was conducted in three phases consisting of ten in vivo and in vitro experiments. This study investigated the effects of zinc on Salmonella growth and survivability in poultry environments, and its ability to induce a molt in single comb white leghorn hens. In part, the antibacterial properties of zinc may reduce environmental contamination in a poultry house by interrupting airborne routes. The first phase involved detecting airborne bacteria by aerosol sampling methods, and then screening any Salmonella mutant (s) that survived desiccation by transposon footprinting. The second phase examined, in vitro, the addition of zinc on the growth kinetics of Salmonella under aerobic or anaerobic conditions, the effects of combinating zinc and acidic conditions on the growth kinetics of Salmonella in vitro under aerobic or anaerobic conditions, and the effects of zinc amended feed on the survival of a dry inoculum of Salmonella. The third phase investigated the ability of zinc propionate, as an alternative salt form of zinc, to induce molt in laying hens, the influence of zinc acetate and zinc propionate on gastrointestinal tract fermentation, and susceptibility of laying hens to S. enteritidis during an induced molt, and the comparison of digestive microbial crop and cecal communities among molted hens fed by either zinc acetate or zinc propionate amended molting diets with hens undergoing feed withdrawal or full fed nonmolted hens using molecular-based denaturing gradient gel electrophoresis.
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The in vivo and in vitro effect of a fructooligosaccharide prebiotic combined with alfalfa molt diets on egg production and salmonella in laying hensDonalson, Lisa Michelle 29 August 2005 (has links)
Salmonellosis affects an estimated 1.4 million people a year with a great majority
of cases never being reported. Salmonella Enteritidis (SE) can be found in a variety of
foods including poultry meat and eggs. Susceptibility of SE colonization is increased by
molting.
Induced molting is used in the poultry industry to rejuvenate the hen??s
reproductive tract and increase post molt egg quality and production. The most common
molting method is complete feed withdrawal. Recent animal welfare pressures have
encouraged the industry to seek alternatives to feed withdrawal with one alternative
being feeding a high fiber diet like alfalfa. Alfalfa is high in protein, but low in energy
which is desirable for a molt diet. Alfalfa??s fermentation properties have been thought to
be an inhibitor in pathogen colonization during molting. Including a prebiotic such as
fructooligosaccharide (FOS) in the molt diet is thought to further decrease colonization
while benefiting the indigenous microflora.
Laying hens were molted using alfalfa combined with different ratios of layer
ration in an in vivo experiment. The hens responded comparably to the alfalfa molt dietsas they did to feed withdrawal as far as post-molt production parameters were
concerned, thus showing that alfalfa was a viable alternative molt diet.
Two in vitro studies were designed to evaluate the fermentation properties of
alfalfa and layer ration combined with the prebiotic FOS and their abilities to inhibit
Salmonella growth. Each treatment was combined with diluted cecal contents and
allowed to ferment. The results showed that the most fermentation occurred when
alfalfa was the substrate and was slightly increased with the addition of FOS. In
addition, combining FOS with alfalfa inhibited Salmonella growth.
To integrate these results, an in vivo study was preformed using an alfalfa/layer
ration diet from the previous in vivo study with FOS. Volatile fatty acids and lactic acid
measurements were made to evaluate fermentation while Salmonella colonization was
measured in pertinent organs and in fecal shedding. The results of this study further
substantiate alfalfa as a molt diet and conclude that the addition of FOS does, while not
statistically significant, further inhibit Salmonella colonization.
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Keeping chooks at home in the Waikato : exploring postcolonial, feminist and kaupapa Māori perspectives /Burnett, Zavier. January 2006 (has links)
Thesis (M.Soc.Sc.)--University of Waikato, 2006. / Includes bibliographical references (leaves 113-119) Also available via the World Wide Web.
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