The Energy-Water-Climate Nexus and Its Impact on Queensland’s Intensive Farming Sector

2018 ◽  
pp. 97-126 ◽  
Author(s):  
Georgina Davis
Keyword(s):  
Intensive Farming

Fresh approaches to antibiotic production

1980 ◽  
Vol 290 (1040) ◽  
pp. 313-328 ◽  
Keyword(s):  
Polyethylene Glycol ◽  
Plant Pathogens ◽  
Growth Promotion ◽  
Antibiotic Production ◽  
Strain Improvement ◽  
Antibiotic Biosynthesis ◽  
Yield Improvement ◽  
Acquired Drug Resistance ◽  
Intensive Farming ◽  
New Antibiotics

New antibiotics are needed, ( a ) to control diseases that are refractory to existing ones either because of intrinsic or acquired drug resistance of the pathogen or because inhibition of the disease is difficult, at present, without damaging the host (fungal and viral diseases, and tumours), ( b ) for the control of plant pathogens and of invertebrates such as helminths, insects, etc., and ( c ) for growth promotion in intensive farming. Numerous new antibiotics are still being obtained from wild microbes, especially actinomycetes. Chemical modification of existing compounds has also had notable success. Here we explore the uses, actual and potential, of genetics to generate new antibiotics and to satisfy the ever-present need to increase yield. Yield improvement has depended in the past on mutation and selection, combined with optimization of fermentation conditions. Progress would be greatly accelerated by screening random recombinants between divergent high-yielding strains. Strain improvement may also be possible by the introduction of extra copies of genes of which the products are rate-limiting, or of genes conferring beneficial growth characteristics. Although new antibiotics can be generated by mutation, either through disturbing known biosyntheses or by activating ‘silent’ genes, we see more promise in interspecific recombination between strains producing different secondary metabolites, generating producers of ‘hybrid’ antibiotics. As with proposals for yield improvement, there are two major strategies for obtaining interesting recombinants of this kind: random recombination between appropriate strains, or the deliberate movement of particular biosynthetic abilities between strains. The development of protoplast technology in actinomycetes, fungi and bacilli has been instrumental in bringing these idealized strategies to the horizon. Protoplasts of the same or different species can be induced to fuse by polyethylene glycol. At least in intraspecific fusion of streptomycetes, random and high frequency recombination follows. Protoplasts can also be used as recipients for isolated DNA, again in the presence of polyethylene glycol, so that the deliberate introduction of particular genes into production strains can be realistically envisaged. Various kinds of DNA cloning vectors are being developed to this end. Gene cloning techniques also offer rich possibilities for the analysis of the genetic control of antibiotic biosynthesis, knowledge of which is, at present, minimal. The information that should soon accrue can be expected to have profound effects on the application of genetics to industrial microbiology.

scholarly journals Biochar and zeolites did not improve phosphorus uptake or crop productivity in a field trial performed in an irrigated intensive farming system

2021 ◽  
Author(s):  
Margarida Arrobas ◽  
João V. Decker ◽  
Bruna L. Feix ◽  
Wilson I. Godoy ◽  
Carlos A. Casali ◽  
...  
Keyword(s):  
Field Trial ◽  
Phosphorus Uptake ◽  
Farming System ◽  
Crop Productivity ◽  
Intensive Farming

scholarly journals Occurrence of mcr-1 in Escherichia coli from rabbits of intensive farming

2018 ◽  
Vol 227 ◽  
pp. 78-81 ◽  
Author(s):  
Joana Freitas-Silva ◽  
Ângela S. Inácio ◽  
Joana Mourão ◽  
Patrícia Antunes ◽  
Ângelo Mendes ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Intensive Farming

scholarly journals Association between periphyton and bioflocs systems in intensive culture of juvenile Nile tilapia

2016 ◽  
Vol 38 (2) ◽  
pp. 119 ◽  
Author(s):  
Davi De Holanda Cavalcante ◽  
Francisco Roberto dos Santos Lima ◽  
Vanessa Tomaz Rebouças ◽  
Marcelo Vinícius do Carmo e Sá
Keyword(s):  
Water Quality ◽  
Growth Rate ◽  
Nile Tilapia ◽  
Specific Growth ◽  
Block Design ◽  
Intensive Culture ◽  
Effluent Quality ◽  
Intensive Farming ◽  
Randomized Block Design ◽  
Underwater Structure

The present work aimed at determining the effects of the association between the periphyton-based system with the bioflocs-based system in the intensive culture of juvenile Nile tilapia (1.56 ± 0.07 g; 72 fish m-3), on variables of water quality, growth performance and effluent quality after 10 weeks. The experiment was arranged in a 2 x 2 factorial randomized block design with four treatments and five repetitions each. The factors tested were the following: ‘underwater structure’ (absence and presence) and ‘adjustment of the C: N ratio of water’ (no and yes). The final fish body weight, specific growth rate and yield were higher (p < 0.05) in the C: N-adjusted tanks. The presence of submerged structures in the tanks had no significant influence on those same variables. It was concluded that the periphyton-based system is not indicated for intensive farming of Nile tilapia, in which there is a high allowance of artificial feed to fish. 

scholarly journals Comparison of arthropod communities between high and low input maize farms in Mexico

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
E. del-Val ◽  
E. Ramírez ◽  
M. Astier
Keyword(s):  
Sustainable Agriculture ◽  
Management Practices ◽  
Agricultural Practices ◽  
Sampling Period ◽  
Arthropod Communities ◽  
Arthropod Diversity ◽  
Low Input ◽  
Intensive Farming ◽  
Arthropod Predators ◽  
Animal Communities

Abstract Background Animal communities are vulnerable to agricultural practices. Intensive farming considerably reduces overall arthropod diversity, but not necessarily pest abundance. Natural control of herbivores in agroecosystems is accomplished by predators and parasitoids, but in intensified agricultural regimes, the chemical control used to reduce pest abundances also affects pests’ natural enemies. To achieve more sustainable agriculture, there is a need to better understand the susceptibility of predators to conventional management. Methods In order to quantify the arthropod diversity associated with different schemes of agricultural management of maize, we evaluated agricultural fields under two contrasting management regimens in Michoacán, México during the spring–summer cycle of 2011. Arthropod communities were evaluated in plots with conventional high-input versus low-input agriculture in two sites—one rainfed and one with irrigation. The experimental units consisted of twelve 1 ha agricultural plots. To sample arthropods, we used 9 pitfall traps per agricultural plot. Results During the sampling period, we detected a total of 14,315 arthropods belonging to 12 Orders and 253 morphospecies. Arthropod community composition was significantly different between the sites, and in the rain-fed site, we also found differences between management practices. Predators, particularly ants, were more abundant in low-input sites. Herbivory levels were similar in all fields, with an average of 18% of leaf area lost per plant. Conclusions Our results suggest that conventional farming is not reducing herbivore abundances or damage inflicted to plants, but is affecting arthropod predators. We discuss repercussions for sustainable agriculture.

scholarly journals The Fatty Acid Profile of Meat from New Zealand White Rabbits Raised under Intensive and Extensive Production Systems

Animals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3126
Author(s):  
Tomasz Daszkiewicz ◽  
Andrzej Gugołek ◽  
Dorota Kubiak ◽  
Krzysztof Kerbaum ◽  
Ewa Burczyk
Keyword(s):  
Fatty Acid ◽  
New Zealand ◽  
Production Systems ◽  
Farming Systems ◽  
Barley Grain ◽  
Wire Mesh ◽  
Free Standing ◽  
Intensive Farming ◽  
New Zealand White Rabbits ◽  
Pelleted Diet

The aim of this study was to compare the fatty acid (FA) profile of meat from New Zealand White rabbits raised from 30 to 90 days of age under intensive (IPS) and extensive (EPS) production systems. In group IPS, the rabbits were housed in wire mesh cages with a slatted floor (16.7 animals/m2) and were fed a commercial pelleted diet. In group EPS, the rabbits were housed in free-standing cages on straw litter (2.5 animals/m2) and were fed a conventional farm-made diet (green fodder, barley grain, stale bread, hay). The FA profile of intramuscular fat (IMF) was analyzed in samples of Longissimus thoracis et lumborum (LTL) muscle. The analyzed production systems had no significant effect on the content of most FAs in IMF. However, the differences between group means contributed to more desirable values of the quality indicators of IMF (in particular in the LTL muscle) in group IPS. The study demonstrated that the claim that meat produced under less intensive farming systems is of superior quality could be an oversimplified generalization that should be validated in research.

scholarly journals Hyper-intensive farming white shrimp Litopenaeus vannamei (Decapoda: Penaeidae) in a seawater tank under semi-controlled conditions

2013 ◽  
Vol 5 (1) ◽  
pp. 69-74
Author(s):  
A. A. Ortega-Salas ◽  
L. A. Rendón M.
Keyword(s):  
Litopenaeus Vannamei ◽  
Maximum Likelihood Method ◽  
High Density ◽  
White Shrimp ◽  
Likelihood Method ◽  
Food Conversion ◽  
High Density Culture ◽  
Intensive Farming ◽  
Controlled Conditions ◽  
Commercial Size

Shrimp development to a commercial size in high density culture saves food and avoids predators and disease. Our study was conducted to calculate the growth of white shrimp Litopenaeus vannamei by hyper-intensive cultivation under semi-controlled conditions. We seeded at a density of 550 shrimp per m3 during the first cycle and 400 shrimp per m3 in the second cycle in an outdoor tank of 6m3or 6m2 covered with mesh, constant aeration. The shrimp were fed Artemia franciscana during the first two weeks and camaronina pellets (35% protein) as required, in food baskets, aftterwards. The temperature ranged from 22,3 to 31,3°C, pH 7,5-8,7, oxygen 4,26±1,43. The tanks are siphoned of debris every other day, and water was replaced according to a program. The food conversion ratio (FCR) was 1:1,3. The shrimp were measured weekly to calculate growth with the Bertalanffy model. Survival in the first cycle was 95,8 ( 97,9% for the second cycle). Population parameters (maximum likelihood method) for the first cycle were k=0,0301, L∞ =322,16 and t0 =-0,8852; second cycle: k=0,0203, L∞ =294,42 and t0 =-5,3771. There was rapid growth during the first 10 weeks. Biomass was 27kg for the first cycle (second: 16kg). KEY WORDSGrowth, high density, survival, biomass, semi-controlled conditions. 

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