The current data provide estimates of the flow of nitrogen (N), calcium (Ca) and phosphorus (P) in Shaver White layers housed under conventional cage (CC) and enriched cage (EC) systems from 19 to 63 wks of age. The experiment was conducted at the University of Manitoba poultry unit. Both feed disappearance (P < 0.01) (92.5 vs. 95.0 ± 0.6 g/hen/d, DM basis) and manure output (P < 0.01) (79.8 vs. 91.3 ± 1.2 g/hen/d, fresh basis and 27.0 vs. 28.1 ± 0.2 g/hen/d, DM basis) were lower in hens housed in EC compared to CC. Manure DM was 34.1 and 31.0 ± 0.3% for EC and CC, respectively. Feed conversion ratio; body weight; and egg production, weight and mass were not significantly different between the two systems. Although there was no difference in the overall manure N (EC: 1.94 vs. CC: 1.96 ± 0.02 g/hen/d, respectively), N balance was greater (P < 0.05) for the CC compared to EC system (85.0 vs. 30.2 ± 13.6 mg/hen/d, respectively). Lower (P < 0.01) Ca and P excretions were observed in EC (Ca: 2.11 vs. 2.29 ± 0.04 and P: 0.619 vs. 0.643 ± 0.005 g/hen/d) compared to CC. Overall egg N output was similar between the systems. Although lower Ca deposition (P < 0.0001) (2.07 vs. 2.13 ± 0.01 g/hen/d) and output (P < 0.05) (38.3 vs. 38.8 ± 0.15 mg/g egg) were noted in eggs from EC compared to CC, shell quality measurements were not different between the two systems. In addition, Ca outputs in eggs expressed as a proportion of Ca intake in both systems were similar (56.5 vs. 56.6 ± 0.51). Although overall mean P retention (-7.22 vs. -7.45 ± 0.71% P intake) was not different between the two groups of hens, Ca retention was higher (P < 0.05) in EC than CC hens (-1.37 vs. -4.76 ± 0.89% Ca intake, respectively). In addition to providing environmental enrichment and maintaining the production performance to the levels of those achieved by CC systems, EC may also help in reducing Ca and P excretions and improving their efficiency of utilization.

The current data provide estimates of the flow of nitrogen (N), calcium (Ca) and phosphorus (P) in Shaver White layers housed under conventional cage (CC) and enriched cage (EC) systems from 19 to 63 wks of age. The experiment was conducted at the University of Manitoba poultry unit. Both feed disappearance (P < 0.01) (92.5 vs. 95.0 ± 0.6 g/hen/d, DM basis) and manure output (P < 0.01) (79.8 vs. 91.3 ± 1.2 g/hen/d, fresh basis and 27.0 vs. 28.1 ± 0.2 g/hen/d, DM basis) were lower in hens housed in EC compared to CC. Manure DM was 34.1 and 31.0 ± 0.3% for EC and CC, respectively. Feed conversion ratio; body weight; and egg production, weight and mass were not significantly different between the two systems. Although there was no difference in the overall manure N (EC: 1.94 vs. CC: 1.96 ± 0.02 g/hen/d, respectively), N balance was greater (P < 0.05) for the CC compared to EC system (85.0 vs. 30.2 ± 13.6 mg/hen/d, respectively). Lower (P < 0.01) Ca and P excretions were observed in EC (Ca: 2.11 vs. 2.29 ± 0.04 and P: 0.619 vs. 0.643 ± 0.005 g/hen/d) compared to CC. Overall egg N output was similar between the systems. Although lower Ca deposition (P < 0.0001) (2.07 vs. 2.13 ± 0.01 g/hen/d) and output (P < 0.05) (38.3 vs. 38.8 ± 0.15 mg/g egg) were noted in eggs from EC compared to CC, shell quality measurements were not different between the two systems. In addition, Ca outputs in eggs expressed as a proportion of Ca intake in both systems were similar (56.5 vs. 56.6 ± 0.51). Although overall mean P retention (-7.22 vs. -7.45 ± 0.71% P intake) was not different between the two groups of hens, Ca retention was higher (P < 0.05) in EC than CC hens (-1.37 vs. -4.76 ± 0.89% Ca intake, respectively). In addition to providing environmental enrichment and maintaining the production performance to the levels of those achieved by CC systems, EC may also help in reducing Ca and P excretions and improving their efficiency of utilization.

In view of the foreign mariculture is gradually diversified, and even has a trend that the fish cage aquaculture combines with algae culture at the same facility. A submersible single-point-mooring (SPM) cage system was modified and installed in-situ to investigate the feasibility of the cage system. A numercial model was established to simulate the cage dynamic motion as well as the mooring line tension. A detailed cage construction process was described in this study. Tension meter was used to keep track of mooring line tension, while the ADCP( Acoustic Doppler Current Profiler) was utilized to record the sea state during the test period. Those data were used to validate the numerical model. The field experiements were carried out at a location north to Xiaoliuqiu island. Since the testing period was in winter, the wave height was relativly calm and found to be between 0.5 and 1.2 m, wave period 4~7 seconds, and wave current about 0.2~0.6 m/s. The numerical results indicate that the maximum mooring line tension has good agreement with the meauresments of the tension meter. These comparisons verify that this numerical model is sufficient to simulate this kind of alage cage systems.

Abstract This research is to develop a new compound cage system that not only has the benefit of the traditional cage system but also has a series of oyster containers hanged on the circumference of the floating collar to add economic value to the cage aquaculture industry. The purpose of this study is to investigate the cage net deformation rate and the maximum mooring tension at the anchor under three types of Liuchiu sea states. The results of numerical simulation could be used as valuable guide for fish farmers and aquacultural cage designers. The developed numerical method is based on a lumped-mass approach to build a system of motion equations, and then utilizes the fourth order Runge-Kutta method to solve the motion equations. The numerical results reveal that under regular wave conditions, the cage net deformation rate for the compound cage system is slightly less than that of the traditional cage system, but the maximum mooring tension has reversed effect, i.e., the compound cage system has higher mooring tension than that of traditional one. As for the cases of irregular waves, the numerical results indicate that the cage net deformed so seriously that the fish can¡¦t survived at the sea condition of typhoon 50-year return period. To overcome this net shrinkage problem, an improved scheme is necessary to be implemented before a real compound cage system is installed in the open sea.

No description available.

Inovação em produção animal tem sido cada vez mais exigido pelos consumidores. No ambito de produção de postura, a maior demanda é por ovos provenientes de sistemas alternativos às gaiolas tradicionais, majoritariamente pelas tendencias observadas na Europa, e dessa forma, pesquisas ressaltando a realidade brasileira estão sendo realizadas. O objetivo deste estudo foi avaliar parametros produtivos e de bem-estar em dois contextos de sistemas produtivos, sob variadas densidades de alojamento. Para isso 250 aves Lohmann Brown&reg; foram distribuídas em delineamento inteiramente casualizado (DIC) com os tratamentos organizados em esquema fatorial 2 x 4, sendo 2 sistemas de alojamento (convencional e cage-free) e 4 densidades (375,00; 450,00; 562,50 e 750,00 cm2/ave), com 6 repetições. O período experimental foi de 21 a 36 semanas de idade das poedeiras, totalizando 4 ciclos de 28 dias cada. Foram avaliados desempenho produtivo (produção de ovos, consumo de ração, conversão alimentar por kg de ovos), qualidade de ovos (peso, coloração de gema, índice gema, % de gema, % albumen, % casca, espessura e resistência a quebra, e unidade Haugh) e indicadores de bem-estar (frequência respiratória e cardíaca, temperatura clocal, escore de lesão corporal, concentração d eIgY na gema) Observou-se interação entre sistema de produção e densidade de alojamento para: % postura, consumo de ração, conversão alimentar por kg de ovos, peso do ovo, % de gema, % albúmen, espessura de casca. O aumento de densidade promoveu efeito significativo para % postura, consumo de ração, temperatura cloacal, lesão em quilha e em pés. O tipo de sistema de produção afetou consumo de ração, conversão alimentar por kg de ovos, peso do ovo, coloração de gema, índice gema, resistência à quebra, frequência cardíaca temperatura cloacal, lesões de quilha e pés e concentração de IgY na gema. Os resultados deste estudo demonstram que tanto o sistema de produção quanto a densidade de alojamento estão ligados a efeitos produtivos, de qualidade de ovos, e de bem-estar animal. / Innovation in animal production has been increasingly demanded by consumers. In the field of egg production, the greatest demand is for eggs coming from alternative systems to traditional cages, mostly from the trends observed in Europe, and thus, research highlighting the Brazilian reality is being carried out. The objective of this study was to evaluate productive and welfare parameters in two contexts of productive systems, under different stocking densities. For this purpose, 250 Lohmann Brown&reg; birds were distributed in a completely randomized design with treatments arranged in a 2 x 4 factorial scheme, with 2 housing systems (conventional and cage-free) and 4 densities (375.00; 450.00, 562.50 and 750.00 cm2 / bird), with 6 replicates. The experimental period was 21 to 36 weeks of age, totalling 4 cycles of 28 days each. (Egg weight, feed intake, feed conversion per kg of egg), egg quality (weight, yolk color, yolk index, % yolk,% albumen,% shell, shell thickness and resistance to breakage, and Haugh unit) and indicators of welfare (respiratory rate and heart rate, body temperature, body lesion score, IgY concentration in the yolk). The interaction between production system and housing density was observed for: % laying, feed intake , feed conversion per kg of eggs, egg weight, % yolk, % albumen, shell thickness. The increase in density had a significant effect on % laying, feed intake, cloacal temperature, keel and foot injury. The type of production system affected feed intake, feed conversion per kg of egg, egg weight, yolk color, yolk index, breaking strength, cloacal temperature, keel and foot lesions, and IgY concentration in the yolk. The results of this study demonstrate that both the production system and housing density are linked to productive effects, egg quality, and animal welfare.

Inovação em produção animal tem sido cada vez mais exigido pelos consumidores. No ambito de produção de postura, a maior demanda é por ovos provenientes de sistemas alternativos às gaiolas tradicionais, majoritariamente pelas tendencias observadas na Europa, e dessa forma, pesquisas ressaltando a realidade brasileira estão sendo realizadas. O objetivo deste estudo foi avaliar parametros produtivos e de bem-estar em dois contextos de sistemas produtivos, sob variadas densidades de alojamento. Para isso 250 aves Lohmann Brown&reg; foram distribuídas em delineamento inteiramente casualizado (DIC) com os tratamentos organizados em esquema fatorial 2 x 4, sendo 2 sistemas de alojamento (convencional e cage-free) e 4 densidades (375,00; 450,00; 562,50 e 750,00 cm2/ave), com 6 repetições. O período experimental foi de 21 a 36 semanas de idade das poedeiras, totalizando 4 ciclos de 28 dias cada. Foram avaliados desempenho produtivo (produção de ovos, consumo de ração, conversão alimentar por kg de ovos), qualidade de ovos (peso, coloração de gema, índice gema, % de gema, % albumen, % casca, espessura e resistência a quebra, e unidade Haugh) e indicadores de bem-estar (frequência respiratória e cardíaca, temperatura clocal, escore de lesão corporal, concentração d eIgY na gema) Observou-se interação entre sistema de produção e densidade de alojamento para: % postura, consumo de ração, conversão alimentar por kg de ovos, peso do ovo, % de gema, % albúmen, espessura de casca. O aumento de densidade promoveu efeito significativo para % postura, consumo de ração, temperatura cloacal, lesão em quilha e em pés. O tipo de sistema de produção afetou consumo de ração, conversão alimentar por kg de ovos, peso do ovo, coloração de gema, índice gema, resistência à quebra, frequência cardíaca temperatura cloacal, lesões de quilha e pés e concentração de IgY na gema. Os resultados deste estudo demonstram que tanto o sistema de produção quanto a densidade de alojamento estão ligados a efeitos produtivos, de qualidade de ovos, e de bem-estar animal. / Innovation in animal production has been increasingly demanded by consumers. In the field of egg production, the greatest demand is for eggs coming from alternative systems to traditional cages, mostly from the trends observed in Europe, and thus, research highlighting the Brazilian reality is being carried out. The objective of this study was to evaluate productive and welfare parameters in two contexts of productive systems, under different stocking densities. For this purpose, 250 Lohmann Brown&reg; birds were distributed in a completely randomized design with treatments arranged in a 2 x 4 factorial scheme, with 2 housing systems (conventional and cage-free) and 4 densities (375.00; 450.00, 562.50 and 750.00 cm2 / bird), with 6 replicates. The experimental period was 21 to 36 weeks of age, totalling 4 cycles of 28 days each. (Egg weight, feed intake, feed conversion per kg of egg), egg quality (weight, yolk color, yolk index, % yolk,% albumen,% shell, shell thickness and resistance to breakage, and Haugh unit) and indicators of welfare (respiratory rate and heart rate, body temperature, body lesion score, IgY concentration in the yolk). The interaction between production system and housing density was observed for: % laying, feed intake , feed conversion per kg of eggs, egg weight, % yolk, % albumen, shell thickness. The increase in density had a significant effect on % laying, feed intake, cloacal temperature, keel and foot injury. The type of production system affected feed intake, feed conversion per kg of egg, egg weight, yolk color, yolk index, breaking strength, cloacal temperature, keel and foot lesions, and IgY concentration in the yolk. The results of this study demonstrate that both the production system and housing density are linked to productive effects, egg quality, and animal welfare.

Thesis (MScAgric (Agricultural Economics))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The rising demand of fish due to population growth coupled by stagnation of fish supply from natural capture has led the world to turn to aquaculture to fill in the gap between fish supply and demand. Aquaculture has emerged as the only sustainable way of supplying the rising population with fish. However the rapid expansion of aquaculture has been met with growing concerns over its environmental effects especially waste produced from aquaculture. The net cage system that is currently being used by small scale trout farmers in the Western Cape is an open water based system where release of waste into the water bodies is inevitable and this put into question the long term sustainability of trout farming using net cages in irrigation dams in the Western Cape. This study sought to compare identified production techniques that can be used by aquaculture farmers to reduce accumulation of organic waste in irrigation dams. The proposed ‘clean’ production techniques include use of net cages fitted with Lift-up system, semi intensive floating tank system (SIFTS) and intergrated aquaculture systems. The study revealed that the intergrated aquaculture system is the most effective way of recovering waste that shows great potential of moving aquaculture towards long term sustainability as it fullfills sustainability dimensions such as ‘zero emission’, nutrient recycling and integrated production. Mechanical methods of recovering waste such as Lift-up system and SIFTS are also effective in recovering particulate waste but however dissolved nutrients are lost into the environment. The study went on further to investigate if economic, environmental and social benefits of recovering waste from irrigation dams outweigh the costs of recovering waste using different production techniques. Models of small scale aquaculture farms using the three identified production techniques were developed and compared with a modelled small scale net cage farm where there was no waste recovery. A comparative financial analysis of the modelled small scale trout farms using alternative production techniques carried out showed that trout production using any of the three alternative ‘clean’ production techniques is financially viable with the SIFTS production technique giving the farmer the highest returns, followed by the intergrated system, then the net cage with a Lift-up system and lastly the net cage system without waste recovery. The second part of the study used the contingent valuation method to estimate the environmental and social benefits of removing waste from dams. Households revealed that they were willing to pay (WTP) R40 on average annually to improve water quality from a state where eutrophication had occurred to a state suitable for irrigation and aquaculture. To improve water quality from a state suitable for irrigation to a state suitable for swimming, households were willing to pay R16.67 annually. If water was to be improved from a state suitable for irrigation to a level suitable for domestic purposes, average willingness to pay (WTP) was R26.17 annually. WTP indicate that besides financial benefits associated with using ‘clean’ production techniques there are environmental and social benefits that will arise to the farm community using water from the irrigation dams. / AFRIKAANSE OPSOMMING: Die stygende vraag na vis as gevolg van bevolkingsgroei, tesame met die stagnering van die aanbod van vis vanaf natuurlike vangste het daartoe aanleiding gegee dat die oë van die wêreld op akwakultuur gerig is om die gaping in die voorsiening van vis te vul. Akwakultuur het ontwikkel as die enigste volhoubare manier om aan die groeiende vraag na vis te voldoen. Die vinnige uitbreiding van akwakultuur het egter toenemende besorgdheid in die nadelige omgewingsimpak, veral ten opsigte van akwakultuurafval, tot gevolg gehad. Die nethokstelsel wat tans deur kleinskaalse forelboere in die Wes-Kaap in oop watergebaseerde sisteme gebruik word en die vrystelling van afval in die wateromgewings wat onafwendbaar is, plaas ’n vraagteken oor die langtermyn volhoubaarheid van die nethokstelsel forelboerdery in besproeiingsdamme in die Wes- Kaap. Die studie het ten doel gehad om geïdentifiseerde produksiestelsels wat deur akwakultuurboere gebruik kan word om die akkummulasie van organiese afval in besproeiingsdamme te verminder, te vergelyk. Die voorgestelde “skoon” produksietegnieke sluit in nethokke wat aan ’n opligstelsel gekoppel word, ‘n semi-intensiewe drywende tenk- stelsel (“SIFTS system” in Engels) en ‘n geïntegreerde akwakultuurstelsel. Met hierdie studie is bevind dat die geïntegreerde stelsel die mees effektiewe manier is om afval te herwin en toon potensiaal om akwakultuur op ’n vohoubare pad te plaas aangesien dit aan die volhoubaarheidsdimensies van geen emissie, voedingstofherwinning en geïntegreerde produksie voldoen. Meganiese metodes van afvalherwinning soos die nethokopligstelsel en die SIFTS-stelsel is effektief in die herwinning van vastestofdeeltjies, maar opgeloste voedingstowwe word steeds in die omgewing vrygestel. Die studie het voorts ten doel gehad om te bepaal of die ekonomiese, omgewings- en sosiale voordele om afval uit besproeiingsdamme te herwin, groter is as die herwinningskoste van die verskillende produksietegnieke. Modelle van kleinskaalse akwakultuurplase wat die drie geïdentifiseerde produksiestelsels gebruik, is ontwikkel en aangewend om te vergelyk met ’n nethokstelsel waar geen afvalherwinning gedoen word nie. ’n Vergelykende finansiële ontleding van die gemodelleerde kleinskaalse forelboerderye met die verskillende produksietegnieke is gedoen en daar is bevind dat enige een van die drie “skoon” stelsels finansieel lewensvatbaar is, met die SIFTS-stelsel wat die hoogste vergoeding aan die boer bied, gevolg deur die geïntegreerde stelsel, dan die nethokke aan ’n opligstelsel en dan die nethokstelsel sonder afvalherwinning. Die tweede deel van die studie het van die voorwaardelike (“contingent”) waardasiemetode gebruik gemaak om die omgewings- en sosiale voordele om afval uit besproeiingsdamme te verwyder, te bepaal. Huishoudings het aangetoon dat hulle bereid sou wees om tot R40 per jaar te betaal om die waterkwaliteit te verbeter vanaf ’n toestand waar eutrifikasie plaasgevind het na ’n toestand waar die water vir besproeiing en akwakultuur geskik sou wees. Om die waterkwaliteit vanaf ’n toestand geskik vir besproeiing te verander na ’n toestand geskik om in te swem, sou huishoudings bereid wees om R16.67 per jaar te betaal. Indien water vanaf ’n toestand geskik vir besproeiing verander sou word na ’n toestand geskik vir huishoudelike gebruik, sou huishoudings gewillig wees om jaarliks R26.17 te betaal. Die “gewilligheid om te betaal” dui aan dat daar bo en behalwe die finansiële voordele om van “skoon” produksietegnieke gebruik te maak, ook omgewings- en sosiale voordele vir die plaasgemeenskap bestaan met die gebruik van die water uit die besproeiingsdamme.

Text in English / The study was conducted in two different types of natural ventilated housing systems; one featured with conventional laying cages while other had free-range system features. The aim was to analyse productivity and economic benefit or loss of the Lohmann Brown Lite on different housing (Free-range system and Conventional cage system) with an evaluation of production cost. The total of 49 700 point of lay Lohmann Brown Lite layers pullets were placed in four natural ventilation free-range houses each consist of three rows of two tier conventional laying cages. The other 40 000 point of lay Lohmann Brown Lite layers pullets were place in four free-range houses each with placement of 10 000 chickens. The Cobb Douglas production model was used to determine the productivity of two different housing system by factoring the fixed cost and variable cost of the entire production process. The breakeven point tool was used to analyse the point where the total revenue equals the total variable and fixed expenses and the cost volume profit by measuring the profitability of each housing system (Nabil et al. 2014). The results of the study revealed different productivity between conventional cage system (82.94%) and the free-range system (77.46%). These results led to the acceptance of hypothesis 1 that “the production of Lohmann Brown Lite is the same when they are kept on the free-range system or conventional cage system. The capital investment and operation on conventional cage system showed breakeven at 43 months while free-range system showed breakeven at 60 months. The economic benefit analysis shows that the free-range system has cost benefit of R0.29 and conventional cage system has a cost benefit of R0.26. It means for every rand spent, farmer may get R0.29 Rand as profit for free-range system and every rand spent for conventional cage system can get R0.26 Rand. The economic benefit to farmer is greater on free-range system that lead to acceptance of hypothesis 2 that the economic benefit of egg production is greater on the free-range system compared to conventional cage system. Free-range housing system remain the best alternative to replace the conventional cage housing system. / Agriculture and  Animal Health / M.Sc. (Agriculture)