A description of the potential growth and body composition of two commercial broiler strains     

L. Vargas  N. K. Sakomura  B. B. Leme  F. Antayhua  M. Reis 《British poultry science》2020,61(3):266-273

ABSTRACT

1. The potential growth of feathers and feather-free body and their chemical components was measured in two commercial broiler strains.

2. A total of 200 chicks of each sex x strain were fed adequate amounts of dietary protein using a four-phase feeding programme. Ten birds per genotype were sampled at 14, 28, 42, 56, 70, 84, 98 and 112 d of age. They were weighed before and after being dry-plucked to determine the weight of feathers, and the feather-free body was then minced and analysed for water, protein and lipid.

3. Body weights and chemical composition of males of the two strains were similar throughout the trial. Females of the two strains differed only in their body lipid contents, with mature Cobb females being higher than Ross (1371 vs. 1210 g).

4. Mature body weights of males and females from both strains averaged 8420 g and 6650 g; mature body protein weights averaged 1555 g and 1030 g; and mature body lipid contents averaged 908 and 1290 g, respectively.

5. Rates of maturing per day of body weights of males and females of both strains averaged 0.0385 and 0.0368; feather-free body protein was 0.0316 and 0.0348 and body lipid was 0.0503 and 0.0375, respectively. The rates for body lipid differed between Cobb and Ross females (0.0352 vs. 0.0397/d). Separate equations were required for males and females to describe the allometric relationship between lipid and protein in the feather-free body.

6. The rate of maturing of feathers in females was higher than in males (0.0526 vs. 0398/d) and the mature weight was lower (205 vs. 266 g), respectively. Mature body weights of broilers in this trial were considerably higher than those measured using the same protocol 24 years ago, whereas rates of maturing remained the same.  相似文献   

Selection index based on random regression model in ‘Tahiti’ acid lime     

Malikouski  Renan Garcia  Alves  Rodrigo Silva  Peixoto  Marco Antônio  Ferreira  Filipe Manoel  do Nascimento  Emanuel Ferrari  de Morais  Andréia Lopes  Zucoloto  Moises  das Graças Dias  Kaio Olimpio  Bhering  Leonardo Lopes 《Euphytica》2022,218(11):1-21

Euphytica - Drought tolerance in maize is a complex and polygenic trait, especially in the seedling stage. In plant breeding, complex genetic traits can be improved by genomic selection (GS), which...  相似文献   

Phytopythium chamaehyphon causing corm and root rot of uncultivated taro (Colocasia esculenta)     

Galo  David  Escalante  Cesar  Diaz  Rodrigo  Hartgerink  John E.  Valverde  Rodrigo A. 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):991-995

European Journal of Plant Pathology - Taro (Colocasia esculenta) is a food crop cultivated in tropical areas of the world. However, when uncultivated, taro is considered an invasive plant species...  相似文献   

Diversity of native rhizobia isolated in south Brazil and their growth promotion effect on white clover (Trifolium repens) and rice (Oryza sativa) plants     

Camille E. Granada  Letícia Arruda  Bruno Brito Lisboa  Luciane M. P. Passaglia  Luciano K. Vargas 《Biology and Fertility of Soils》2014,50(1):123-132

In this study, rhizobia strains isolated from white clover (Trifolium repens) root nodules were evaluated in an effort to identify an efficient nitrogen-fixing rhizobia strain that can also improve the growth of rice plants (Oryza sativa). White clover plants were collected from seven sites in south Brazil, and 78 native rhizobia isolates were obtained. The genetic diversity analysis of those isolates was carried out by BOX-polymerase chain reaction. Overall, the native rhizobia isolated showed a high genetic diversity, but when the bacterial isolates from the same site were compared, the diversity was lower. One native rhizobia, POA3 (isolated from the Porto Alegre locality), was able to promote the growth of both plants and is therefore a good candidate for new inoculant formulation. Finally, we can conclude that the community of native rhizobia symbiont of white clover plants in southern Brazil is highly diverse and the growth promotion effect of rhizobia inoculation on rice plants was more pronounced in a poor nutrient substrate condition than in a rich nutrient substrate condition.  相似文献   

Enhancing conservation and use of local vegetable landraces: the Almagro eggplant (Solanum melongena L.) case study     

Maria Hurtado  Santiago Vilanova  Mariola Plazas  Pietro Gramazio  Isabel Andújar  F. Javier Herraiz  Angel Castro  Jaime Prohens 《Genetic Resources and Crop Evolution》2014,61(4):787-795

We have used the Almagro pickling eggplant landrace as a model for the enhancement of a local vegetable landrace. The programme has included characterization, selection, and breeding activities. Considerable intra-landrace diversity has been found for morphological traits and molecular markers. Characteristic morphological traits have allowed its registration as conservation variety. Also, universal and specific simple sequence repeat markers have been found for the Almagro landrace. The chemical characterization revealed that Almagro eggplant has a high content in bioactive phenolics. Organoleptic tests revealed that pickles produced with Almagro eggplant are superior to those of the related Andalusian landrace. The selection programme has led to the development of a pure line with increased yield and reduced fruit calyx prickliness. A participatory breeding programme, in which selection is made by farmers in their own field, has been initiated to introduce the no-prickles trait from three other varieties in the genetic background of the Almagro eggplant. The results of the programmes show that plants with the Almagro eggplant ideotype and with reduced prickliness can be selected in the backcross generations. As a result of the enhancement programme the acreage and total production of Almagro eggplant has tripled in the last decade.  相似文献   

Complementary resource use in intercropped faba bean and cabbage by increased root growth and nitrogen use in organic production     

Sindhuja Shanmugam  Margita Hefner  Jeanett S. Pelck  Rodrigo Labouriau  Hanne L. Kristensen 《Soil Use and Management》2022,38(1):729-740

Intercropping can improve yield and nitrogen use efficiency in organic vegetable production by pairing crops with complementary resource use. An intercrop field experiment was conducted to determine yield, root growth and nitrogen (N) dynamics using faba bean (Vicia faba L.) grown as a vegetable and pointed cabbage (Brassica oleracea var. capitata cv. conica). Both crops were grown in monocropping (MC) and intercropping systems (IC). Minirhizotrons were used to measure root growth. Yield of pointed cabbage per metre row was 28% higher under the IC system than under MC, whereas faba bean yield as fresh seeds did not differ. The land equivalent ratio was 1.06, showing that improved yield under IC resulted from efficient land resource use. Even though MC cabbage had the highest aboveground biomass, total N accumulation was higher under IC and MC faba bean systems. Both root frequency and intensity were greater under IC faba bean rows compared with MC faba bean because of the presence of cabbage roots in faba bean rows. Monocropped cabbage had the highest root intensity and the lowest amount of soil mineral N in the 0–1.5 m depth after harvest. Monocropped cabbage was efficient in assimilating N, whereas MC faba bean was efficient in exporting N as harvestable yield. The nitrogen use efficiency using the IC system (75%) was higher than growing faba bean (44%) and cabbage (65%) alone. Thus, faba bean as an intercrop in organic cabbage production systems improves land and N use efficiency by complementary root growth.  相似文献   

Biobased Solvents for Pressurized Liquid Extraction of Nannochloropsis gaditana Omega-3 Lipids     

Cristina Blanco-Llamero  F. Javier Seorns 《Marine drugs》2021,19(2)

To develop greener extraction alternatives for microalgae biomass, ultrasound assisted extraction (UAE) and pressurized liquid extraction (PLE) with different biobased solvents were investigated, demonstrating that both techniques are useful alternatives for algal lipid extraction. Specifically, Nannochloropsis gaditana lipids were extracted by UAE and PLE at different temperatures and extraction times with sustainable solvents like 2-Methyltetrahydrofuran (2-MeTHF) and its mixtures with ethanol and other alcohols. The best oil yields for both PLE and UAE of N. gaditana were achieved with the mixture of 2-MeTHF:ethanol (1:3), reaching yields of up to 16.3%, for UAE at 50 °C and up to 46.1% for PLE at 120 °C. Lipid composition of the extracts was analyzed by HPLC-ELSD and by GC-MS to determine lipid species and fatty acid profile, respectively. Different fractionation of lipid species was achieved with PLE and solvent mixtures of different polarity. Thus, for the extraction of glycolipids, ethanolic extracts contained higher amounts of glycolipids and EPA, probably due to the higher polarity of the solvent. The optimized method was applied to microalgae Isochrysis galbana and Tetraselmis chuii showing the potential of mixtures of biobased solvents like 2-methyl-THF and ethanol in different proportions to efficiently extract and fractionate lipids from microalgal biomass.  相似文献   

Efficiency of soil-applied ⁶⁷Zn-enriched fertiliser across three consecutive crops     

Edson M. MATTIELLO  Eduardo L. CANCELLIER  Rodrigo C. DA SILVA  Fien DEGRYSE  Roslyn BAIRD  Mike J. MCLAUGHLIN 《土壤圈》2021,31(4):531-537

A very small amount of applied zinc (Zn) is taken up by crops, resulting in low recovery by plants. Adding elemental sulphur to zinc oxide (ZnO) fertiliser could improve Zn solubilisation and exert a higher residual effect on crops than soluble Zn sources. We produced an isotopically labelled Zn-elemental sulphur fertiliser and evaluated its performance in comparison to traditional Zn sources during sequential crop cultivation. Three ⁶⁷Zn-labelled fertilisers, ZnO, zinc sulphate (ZnSO₄), and ZnO co-granulated with elemental sulphur (ZnOS⁰), were soil applied, and their contributions to the uptake of Zn by three consecutive crops, wheat, ryegrass, and corn, were assessed in a 294-d pot experiment. The contributions of Zn fertilisers followed the order:ZnSO₄ > ZnO=ZnOS⁰. The relative contributions of Zn fertilisers were lower in the first crop than in the subsequent crops. The overall recovery of applied Zn by the three crops was higher for ZnSO₄ than for ZnO and ZnOS⁰, reaching 1.56%, 0.45%, and 0.33% of the applied Zn, respectively. Zinc recovery by plants was very low, regardless of the source of Zn. Adding elemental sulphur to ZnO did not increase its effectiveness up to 294 d after application. Fertiliser contribution was higher for the subsequent crops than for the initial crop, indicating the importance of assessing the residual effects of Zn fertilisers.  相似文献   

Land use and climate change impacts on soil organic carbon stocks in semi-arid Spain   总被引：3，自引：2，他引：1  

Juan Albaladejo  Roque Ortiz  Noelia Garcia-Franco  Antonio Ruiz Navarro  Maria Almagro  Javier Garcia Pintado  Maria Martínez-Mena 《Journal of Soils and Sediments》2013,13(2):265-277

Purpose

The sensitivity of soil organic carbon to global change drivers, according to the depth profile, is receiving increasing attention because of its importance in the global carbon cycle and its potential feedback to climate change. A better knowledge of the vertical distribution of SOC and its controlling factors—the aim of this study—will help scientists predict the consequences of global change.

Materials and methods

The study area was the Murcia Province (S.E. Spain) under semiarid Mediterranean conditions. The database used consists of 312 soil profiles collected in a systematic grid, each 12 km² covering a total area of 11,004 km². Statistical analysis to study the relationships between SOC concentration and control factors in different soil use scenarios was conducted at fixed depths of 0–20, 20–40, 40–60, and 60–100 cm.

Results and discussion

SOC concentration in the top 40 cm ranged between 6.1 and 31.5 g?kg^?1, with significant differences according to land use, soil type and lithology, while below this depth, no differences were observed (SOC concentration 2.1–6.8 g?kg^?1). The ANOVA showed that land use was the most important factor controlling SOC concentration in the 0–40 cm depth. Significant differences were found in the relative importance of environmental and textural factors according to land use and soil depth. In forestland, mean annual precipitation and texture were the main predictors of SOC, while in cropland and shrubland, the main predictors were mean annual temperature and lithology. Total SOC stored in the top 1 m in the region was about 79 Tg with a low mean density of 7.18 kg?Cm^?3. The vertical distribution of SOC was shallower in forestland and deeper in cropland. A reduction in rainfall would lead to SOC decrease in forestland and shrubland, and an increase of mean annual temperature would adversely affect SOC in croplands and shrubland. With increasing depth, the relative importance of climatic factors decreases and texture becomes more important in controlling SOC in all land uses.

Conclusions

Due to climate change, impacts will be much greater in surface SOC, the strategies for C sequestration should be focused on subsoil sequestration, which was hindered in forestland due to bedrock limitations to soil depth. In these conditions, sequestration in cropland through appropriate management practices is recommended.  相似文献   

Serotypes,phage types and virulence genes of shiga-producing Escherichia coli isolated from sheep in Spain   总被引：3，自引：0，他引：3  

Rey J  Blanco JE  Blanco M  Mora A  Dahbi G  Alonso JM  Hermoso M  Hermoso J  Alonso MP  Usera MA  González EA  Bernárdez MI  Blanco J 《Veterinary microbiology》2003,94(1):47-56

PROBLEM ADDRESSED: Shiga toxin-producing Escherichia coli (STEC), have emerged as food poisoning pathogens which can cause severe diseases in humans. OBJECTIVE: The aim of this study was to determinate the serotypes and virulence genes of STEC strains isolated from sheep in Spain, with the purpose of determining whether sheep represent a potential source of STEC pathogenic for humans. METHODS AND APPROACH: Faecal swabs obtained from 697 healthy lambs on 35 flocks in Spain during the years 2000 and 2001 were examined for STEC using phenotypic (Vero cells) and genotypic (PCR) methods. RESULTS: STEC O157:H7 strains were isolated from seven (1%) animals in six flocks, whereas non-O157 STEC strains were isolated from 246 (35%) lambs in 33 flocks. A total of 253 ovine STEC strains were identified in this study. PCR showed that 110 (43%) strains carried stx(1) genes, 10 (4%) possessed stx(2) genes and 133 (53%) both stx(1) and stx(2). Enterohaemolysin (ehxA) and intimin (eae) virulence genes were detected in 120 (47%) and in 9 (4%) of the STEC strains. STEC strains belonged to 22 O serogroups and 44 O:H serotypes. However, 70% were of one of these six serogroups (O6, O91, O117, O128, O146, O166) and 71% belonged to only nine serotypes (O6:H10, O76:H19, O91:H-, O117:H-, O128:H-, O128:H2, O146:H21, O157:H7, O166:H28). A total of 10 new O:H serotypes not previously reported in STEC strains were found in this study. Seven strains of serotype O157:H7 possessed intimin type gamma1, and two strains of serotype O156:H- had the new intimin zeta. STEC O157:H7 strains were phage types 54 (four strains), 34 (two strains) and 14 (one strain). CONCLUSIONS: This study confirms that healthy sheep are a major reservoir of STEC pathogenic for humans. However, because the eae gene is present only in a very small proportion of ovine non-O157 STEC, most ovine strains may be less pathogenic.  相似文献