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1.
Poult Sci ; 95(1): 213-24, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26628346

RESUMO

This study was carried out to measure the mass flow and distribution of nutrients (N, C, S, P, and K) as well as solids and moisture in conventional cage (CC), enriched colony (EC), and aviary (AV) laying-hen houses with Lohmann LSL lite hens located on a commercial laying-hen farm in Iowa. The weight of consumed feed and water, and amounts of eggs and manure production were collected weekly from each house for 2 entire flocks for a total of 28 mo. Samples of feed, egg, manure, litter, and hens were regularly taken and analyzed for total solids and nutrients (N, C, S, P, and K). The nutrient losses to the atmosphere were calculated using a mass balance approach. The losses of nutrients were calculated by subtracting the nutrient contents in eggs, manure, and layer body weight gain from the nutrients intake. The research results showed that the feed intake and manure production rates were similar in the 3 houses. The average nutrient intake in feed, in g d(-1) hen(-1), for the 3 houses was 42.0 C, 2.96 N, 0.36 S, 0.55 P, and 0.79 K. The nutrient intake was partitioned as follow: C - 18% in eggs, 28% in manure, and 54% in air losses; N - 34% in eggs, 58% in manure, and 8% in air losses; S - 26% in eggs, 68% in manure, and 6% in air losses; P - 17% in eggs, 79% in manure, and 3.1% in air losses; and K - 9% in eggs, 89% in manure, and 1.6% in air losses. Manure removed from the EC house was drier than manure from the CC or AV house. Among the 3 hen houses studied, the EC house had the lowest nutrient losses and the AV house had the highest losses. Nutrient loss in CC was statistically similar to EC. But loss of N, C, and S in AV differed from CC and EC. Furthermore, the loss of P and K in the 3 housing systems was statistically similar. The AV had a doubled mortality rate compared to CC and EC.


Assuntos
Criação de Animais Domésticos/métodos , Fenômenos Fisiológicos da Nutrição Animal , Galinhas/fisiologia , Ingestão de Energia , Abrigo para Animais , Animais , Peso Corporal , Feminino , Esterco , Necessidades Nutricionais
2.
Huan Jing Ke Xue ; 32(11): 3167-73, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22295608

RESUMO

This study was to define the Variations of soil respiration, the response of influence factors to soil respiration and carbon sink in the total growing season, in winter wheat field of different previous crops. The results showed that: (1) as soil depth increases, the response of temperature to soil respiration rate also increased with a lag; (2) the soil respiration rate was quadric to soil moisture, phosphorus, potassium, soil urease activity, soil temperature, soil moisture as the main factors had an effect on soil respiration rate; soil temperature had the stronger effect on soil respiration rate when potassium had the weaker effect on soil respiration rate; (3) the average carbon emission rate in wheat filed of different previous crops showed as follow: Pepper of previous crops > celery of previous crops > corn of previous crops > eggplant of previous crops. The intensity of carbon "sink" displayed as follow: eggplant of previous crops > celery of previous crops > corn of previous crops > pepper of previous crops. As for the trials of this study, although the soil respiration rate is highest in the winter wheat filed of previous pepper, the amount of carbon fixed is the most. Its ratio of net primary productivity (NPP) and soil carbon release quantity was highest, so carbon sink was the strongest. If rotation planting was arranged according to the purpose of increasing carbon sink and reducing carbon emissions, pepper was relatively appropriate stubbles crop, followed by corn crop, celery and eggplant.


Assuntos
Dióxido de Carbono/metabolismo , Raízes de Plantas/metabolismo , Solo/química , Triticum/crescimento & desenvolvimento , Fósforo/metabolismo , Potássio/metabolismo , Estações do Ano , Microbiologia do Solo , Triticum/metabolismo , Verduras/crescimento & desenvolvimento , Água/metabolismo , Zea mays/crescimento & desenvolvimento
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