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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.
11

FREQÜÊNCIA DE SUPLEMENTAÇÃO E FONTE DE NITROGÊNIO SUPLEMENTAR E SUA RELAÇÃO COM O VALOR ALIMENTAR DE DIETAS BASEADAS EM FENO DE QUICUIO (Pennisetum clandestinum) FORNECIDAS PARA OVINOS / FEEDING FREQUENCY AND DEGRADABLE NITROGEN SOURCE IN RELATION TO FEEDING VALUE AND UTILIZATION OF KIKUIO GRASS (Pennisetum Clandestinum) HAY BASED DIETS

Cadorin Junior, Rui Luiz 15 February 2008 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / An in vivo digestibility experiment was conducted to evaluate the influence of degradable nitrogen source and feeding frequency on the digestion process and utilization of kikuio grass hay. Eight castrated male lamb (35 ± 4 Kg live weight) maintained in individual metabolic cage, were used in a 2x2 factorial experiment according to a replicated 4x4 Latin Square design. Treatments tested were the combination of two supplement feeding frequencies: once (morning) or twice (morning and aftermoon) daily, and two supplements, based on cassava meal plus calcium caseinate or cassava meal plus urea. For all treatments kikuio hay was fed ad. Libitum and the supplements were fed at a rate of 7 g/Kg live weight daily. Animals supplemented twice day consumed higher quantity of the gross fractions, either in absolute values or in proportion to live weight or metabolic weight (P<0,05) and they tended to consume higher quantity of digestible energy and to synthesize more microbial protein (P<0,10). Feeding frequency did not influence the digestibility. When calcium caseinate was fed animal tended (P<0,10) to have higher dry matter intake in relation to live weight and higher organic matter intake in relation to metabolic weight. There was interaction between nitrogen source × frequency of supplementation on intake of both digestible organic matter and digestible energy. Animals receiving supplement with calcium caseinate twice a day and supplemented with urea once a day have higher intake of theses fractions. Animals supplemented once a day presented higher rumen sugar concentration (P<0,05), but pH as well as ammonia and peptides + aminoacid concentration were not affected by supplementation frequencys. Higher concentrations of NH3 and lower concentrations of pep+aa were observed in animals supplemented with urea (P<0,05). The supplement feeding frequency did not influence the digestion process and forage utilization when the nitrogen source was urea, but when the nitrogen source was calcium caseinate, supplementation twice daily improves intake and nutrients offer to the animals. / Para avaliar se as freqüências de oferta de suplemento, com diferentes tipos de nitrogênio degradável, influenciam os processos de digestão e a utilização do feno de uma gramínea tropical, foi realizado um estudo de digestibilidade in vivo, utilizando oito ovinos machos castrados (PV médio 35 ± 4 Kg), mantidos em gaiolas de metabolismo individuais em um delineamento duplo quadrado latino 4x4 em um esquema fatorial 2x2. Como volumoso foi utilizado feno de capim quicuio (Pennisetum clandestinum) com 70 dias de rebrota, como suplemento foi utilizada uma mistura a base de farinha de mandioca mais uréia ou caseinato de cálcio, além de uma mistura de sal mineral comercial e melaço em pó. Os tratamentos foram duas freqüências de suplementação × duas fontes de nitrogênio. As combinações foram suplementação com farinha de mandioca mais caseinato fornecido uma vez ao dia (manhã) e duas vezes ao dia (manhã e tarde) e suplementação com farinha de mandioca mais uréia uma vez ao dia (manhã) e duas vezes ao dia (manhã e tarde) à nível de 7 g/Kg de PV. O volumoso foi fornecido Ad. Libitum duas vezes ao dia (manhã e tarde). Os animais quando suplementados duas vezes ao dia consumiram maior quantidade das frações brutas, tanto em valores absolutos, como em proporção ao PV ou peso metabólico (P<0,05) e tenderam a consumir maior quantidade de energia digestível e a sintetizar mais proteína microbiana (P<0,10). A freqüência de suplementação não influenciou na digestibilidade e a eficiência da síntese de proteína microbiana. Somente houve uma tendência de quando os animais foram suplementados com caseinato consumirem maior quantidade de matéria seca em relação ao peso vivo e matéria orgânica em g/Kg de peso metabólico (P<0,10), não havendo mais nenhum efeito da suplementação com diferentes fontes de nitrogênio degradável no rúmen. Houve interação fonte de nitrogênio × freqüência de suplementação no consumo de matéria orgânica digestível e energia digestível onde os animais quando recebendo suplemento com caseinato duas vezes ao dia e quando suplementados com uréia uma vez ao dia consumiram mais destas frações. Quando os animais foram suplementados uma vez por dia apresentaram maiores concentrações ruminais de açucares (CHO) (P<0,05), e o pH, amônia (NH3) e peptídeos + aminoácidos (pep+aa) não foram influenciados pelas diferentes freqüências de suplementação. Maiores concentrações ruminais de NH3 e menores de pep+aa foram observadas quando os animais foram suplementados com uréia (P<0,05). A suplementação com farinha de mandioca mais caseinato fornecido duas vezes ao dia manifestou ser superior as demais suplementações, no entanto os mecanismos não ficaram bem estabelecidos, necessitando estudos adicionais.
12

Effects of restricted feeding schedule during development and gestation on gilt and sow performance

Schneider, Jason Dean January 1900 (has links)
Doctor of Philosophy / Department of Animal Sciences and Industry / Jim L. Nelssen / The overall objective of these experiments was to develop management and feeding programs to increase sow longevity and productivity by improving welfare conditions. In Exp. 1, 208 gestating sows and 288 gestating gilts were utilized to determine the effect of feeding frequency (2 vs. 6) on performance and welfare issues. Feeding frequency had no affect on growth and reproductive performance in gestating sows; however, increasing the feeding frequency did improve the welfare measurements in this trial. Gilts fed six times a day did have increase ADG during d 0 to 42; however, there was no affect on performance from d 42 to farrowing. In Exp. 2 (630 pigs in 4 studies), increasing the feeding frequency (2 vs. 6) of a restricted feeding level increased growth performance of finishing pigs. This affect is likely due to the increase of available energy above maintenance when compared with the gestating sows. In Exp. 3, different feed drops used for delivering feed were evaluated. The Accu and the Ultra feed drops were more accurate than the Econo feed drop at angles of 90, 75, and 60°. The difference in accuracy is potentially related to the way that the drops attach to the feed line. However, the amount of feed that is collected in each drop appears to increase linearly as the feeder settings are increased. Thus, regression equations for the angle of the feed drop can be developed to adjust for the variability in the amount of accumulated feed. In Exp. 4, Alimet® was used to determine the TID TSAA:Lys ratio for ADG and G:F of 63 and 66% for Genetiporc and 61 and 56% for PIC pigs weighing between 10 to 20 kg. In Exp. 5, the optimal TID Lys:Calorie ratio was estimated to be 3.7 and 4.1 g Lys/Mcal ME for the Genetiporc and PIC pigs weighing between 10 to 20 kg . The ratios were than validated at two energy levels and the amount of TID Lys that was used for lean gain was similar for both genetic lines at approximately 20 g of Lys for each kg of gain.
13

The effects of energy quantity to the reproductive strategies of the sea anemone Aiptasia pulchella Carlgren 1943

Chen, Chien-Hsun 26 June 2000 (has links)
The effects of energy quantity to the reproductive strategies of the sea anemone Aiptasia pulchella Carlgren 1943 Chien-Hsun Chen (Advisors: Drs. Keryea Soong, Chao-Lun Chen) Institute of Marine Biology, National Sun Yat-Sen University, Kaohsiung, 804, Taiwan, R.O.C. Thesis abstract The influences of energy quantity on the sexual and asexual reproduction and possible trade-offs between them in the sea anemone, Aiptasia pulchella were investigated. Different feeding frequencies, light intensities and presence of zooxanthellae were the treatments of energy quantity. Lacerate numbers, lacerate sizes and total weight of lacerates were used to quantify investment in asexual reproduction; oocyte sizes and gonad weights were used as the measures of sexual reproduction. The correlation between total weight of lacerates and that of gonads provided an opportunity for evidence of trade-offs between sexual and asexual reproduction. Under higher feeding frequencies, A. pulchella produced more and larger lacerates as well as larger oocytes and heavier gonads than under lower feeding frequencies. Under lower light intensities, A. pulchella produced more and heavier lacerates with than without zooxanthellae. Lacerate sizes were influenced by light intensities, presence of zooxanthellae and the interaction of the two factors. At intermediate light intensity (2000 lux), Aiptasia pulchella produced heavier gonads than at 0 lux or 10000 lux. A. pulchella produced heavier gonads with than without zooxanthellae. The oocyte sizes of A. pulchella were also influenced by light intensities, zooxanthellae and the interaction of the two. In both sexual or asexual modes of reproduction, A. pulchella performed better under higher than lower feeding frequencies. There were higher level of asexual reproduction for A. pulchella under lower light intensities with zooxanthellae. A. pulchella achieved the highest levels of fecundity, as an indication of sexual reproduction, under a light intensity of 2000 lux in individuals containing zooxanthellae. There is a positive correlation between sexual and asexual investment under different energy regimes. This is not compatible with the prediction of the trade-off hypothesis.
14

Energy requirements and feeding behaviour of salmonids in culture /

Bailey, Jason, January 2003 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2003. / Härtill 5 uppsatser.
15

Protótipo de alimentador automático para a larvicultura da tilápia (Oreochromis niloticus) / Prototype of an automatic feeder for tilapia (Oreochromis niloticus) hatchery

Anschau, Sandra Paula 05 May 2016 (has links)
Made available in DSpace on 2017-07-10T18:13:22Z (GMT). No. of bitstreams: 1 Sandra P Anschau.pdf: 1880583 bytes, checksum: ddb07c1ecd08368a07c24f3fdf129c2a (MD5) Previous issue date: 2016-05-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The food automation provides increased productivity, feed efficiency, uniformity of lots, uniformity in the sexual inverse and the best performance. This study aimed to develop a low cost automatic feeder, by a microcontrolled platform called ARDUINO UNO®, which was able to provide installments feed previously programmed. To the prototype development in question was used basically: flotation and support structure, feed tank and screw conveyor, motor and electronic systems. The support system was deployment with the use of plastic flooring (HDPE-high density polyethylene). The sides of the plastic floor with the aid of clamps were attached PVC tubes with the float feature. The fiberglass feed tank was developed with useful capacity to store five kilograms nine hundred and twenty grams of powder feed with output to screw conveyor, the screw conveyor was machined in nylon material, and is in turn surrounded by a PVC tuber. To drive the screw conveyor it was connected to an electric motor with 12-volt operating voltage rating accopled to a gear unit based on mechanical system called gear motor. It is worth noting that the electronic power system uses a 12-volt rechargeable battery of supplying capacity of 7 Ah, high to necessary to the operation of 14 days. The programming language used was the C language, by Arduino 1.0.3 software. The equipment in question showed satisfactory results in terms of its functionality. The feed frequency became precise in the category of time and quantity since this is an automated system and not depending on a person to handle the fish feeding, since the human being in turn is often inaccurate. Another important point to establish is that the equipment allows changing in the programmatically feed frequency. The developed automatic feeder emphasizes the importance of investing in aquaculture technologies to optimize the cost and improving the feed system in the hatchery. / A automatização alimentar propicia o aumento da produtividade e eficiência alimentar, a uniformidade dos lotes, a homogeneidade na inversão sexual e o melhor desempenho produtivo. Esse trabalho teve por objetivo desenvolver um alimentador automático de baixo custo, por meio de uma plataforma microcontrolada denominada ARDUINO UNO® auxiliada pelo módulo rele, que teve a capacidade de fornecer o alimento parcelado previamente programado. Para o desenvolvimento do protótipo em questão utilizou-se: estrutura para flutuação e sustentação, reservatório de ração e rosca transportadora, sistemas motor e eletrônico. O sistema de sustentação elaborado feito com a utilização de piso plástico (PEAD - polietileno de alta densidade). Nas laterais do piso plástico, por auxílio de abraçadeiras, foram acoplados tubulações de PVC com a funcionalidade de flutuação. O reservatório de ração foi desenvolvido em fibra de vidro com capacidade útil para armazenar cinco quilos, novecentos e vinte gramas de ração em pó e este possui uma saída de quarenta milímetros para a rosca transportadora, que por sua vez foi usinada em material nylon e envolvida por uma tubulação de PVC. Para a movimentação da rosca transportadora conectou-se um motor elétrico com a tensão nominal de operação de 12 volts acoplado a um redutor baseado em sistema mecânico denominado rosca sem fim. Vale salientar que o sistema de alimentação eletrônico utiliza uma bateria recarregável de 12 volts com capacidade de fornecimento de 7 amper hora, superior ao necessário para o funcionamento durante 14 dias. A linguagem de programação utilizada foi a linguagem C, por meio do software Arduino 1.0.3. O equipamento em questão apresentou resultados satisfatórios quanto a sua funcionalidade. A frequência alimentar tornou-se precisa no quesito de tempo e quantidade pois trata-se de um sistema automatizado e não mais dependendo de um indivíduo para alimentar os peixes, pois o ser humano por sua vez é, muitas vezes impreciso. Outro ponto importante a se fixar é que o equipamento permite alteração da frequência alimentar de forma programada. O alimentador automático desenvolvido ressalta a importância de se investir em tecnologias na aquicultura para a otimização do custo e aperfeiçoamento do sistema alimentar na larvicultura.
16

Breastfeeding and introduction of other foods : A prospective longitudinal study in Sweden

Hörnell, Agneta January 2000 (has links)
<p>This study, based on daily recordings of infant feeding, comprised 506 infants from Uppsala, Sweden. All mothers had had previous breastfeeding experience of at least 4 months, and were planning to breastfeed the index child for ≥6 months.</p><p>Among exclusively breastfed infants there were wide variations in breastfeeding frequency and suckling duration per 24 hours both between infants and in the individual infant over time in the first 6 months. Most infants had an average of 1.0-2.9 feeds per night. Infants using a pacifier had fewer feeds and a shorter total suckling duration per 24 hours, and stopped breastfeeding earlier than infants not using a pacifier. These associations were not found for thumb sucking.</p><p>Accustoming the infants to solids was a lengthy process, the longer the younger the infant at introduction, and was associated with small changes in pattern and duration of breastfeeding. In contrast, formula was usually given in large amounts from the beginning, and when formula was given regularly the daily breastfeeding frequency and suckling duration declined swiftly. The younger an infant at the start of regular formula feeds, the shorter the breastfeeding duration. Occasional formula feeds did not affect the breastfeeding duration.</p><p>It is important for health personnel and parents to keep in mind that exclusively breastfed infants are not a homogeneous group, but rather members of distinct 'breastfeeding entities'. Moreover, if the aim is to introduce other foods 'under the protection of breast milk' it is important to realise that formula is also 'another food' and needs to be treated as such.</p>
17

Breastfeeding and introduction of other foods : A prospective longitudinal study in Sweden

Hörnell, Agneta January 2000 (has links)
This study, based on daily recordings of infant feeding, comprised 506 infants from Uppsala, Sweden. All mothers had had previous breastfeeding experience of at least 4 months, and were planning to breastfeed the index child for ≥6 months. Among exclusively breastfed infants there were wide variations in breastfeeding frequency and suckling duration per 24 hours both between infants and in the individual infant over time in the first 6 months. Most infants had an average of 1.0-2.9 feeds per night. Infants using a pacifier had fewer feeds and a shorter total suckling duration per 24 hours, and stopped breastfeeding earlier than infants not using a pacifier. These associations were not found for thumb sucking. Accustoming the infants to solids was a lengthy process, the longer the younger the infant at introduction, and was associated with small changes in pattern and duration of breastfeeding. In contrast, formula was usually given in large amounts from the beginning, and when formula was given regularly the daily breastfeeding frequency and suckling duration declined swiftly. The younger an infant at the start of regular formula feeds, the shorter the breastfeeding duration. Occasional formula feeds did not affect the breastfeeding duration. It is important for health personnel and parents to keep in mind that exclusively breastfed infants are not a homogeneous group, but rather members of distinct 'breastfeeding entities'. Moreover, if the aim is to introduce other foods 'under the protection of breast milk' it is important to realise that formula is also 'another food' and needs to be treated as such.

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