Effects of rumen-protected oil supplementation on finishing grazing beef cattle

Tropical Animal Health and Production - The objective of this study was to evaluate the effects of rumen-protected oil (soybean and palm oil) in supplements for beef cattle during the fattening...     

Combination of pelleting and monensin does not affect antioxidant properties and fatty acids in milk of grazing dairy cows supplemented with a concentrate containing soybean seeds

This study was performed with the main objective of evaluating the effect of the combination of pelleting and monensin on fatty acids (FA) composition, the concentration of total polyphenols and flavonoids, and the oxidative stability of milk in cows fed a concentrate containing soybean seeds. Eight Holstein multiparous cows were distributed in a replicated Latin square design. The four supplement treatments consisted of the combination of two factors (pelleting and monensin) and one concentrate as follows: (1) unpelleted concentrate with no monensin (CO); (2) pelleted concentrate with no monensin (PE); (3) unpelleted concentrate with 96 mg of monensin/kg of dry matter, DM (MO); and (4) pelleted concentrate with 96 mg of monensin/kg of DM (PM). There was no interaction between pelleting and monensin for milk production and concentration of milk protein, lactose, total polyphenols, flavonoids, conjugated dienes (CD), and reducing power. Fat and total solids concentration in milk were decreased when cows were fed pelleted (PE and PM) concentrates. Feeding cows with PE and PM concentrates increased the CD concentration in milk. Regarding milk FA concentration, there was no difference among treatments for total saturated, monounsaturated, and polyunsaturated FA. The most prominent result was that pelleting increased the milk concentration of omega-3 FA. Altogether, the present study suggests that the pelleting process can improve the milk fat quality by increasing the omega-3 FA, while the combination of pelleting and monensin in the diet of grazing dairy cows fed soybean-based concentrate adds no further improvements to FA profiles and oxidative stability of milk.

     

Long-term dynamic of nestedness in bird assemblages inhabiting fragmented landscapes

Landscape Ecology - Nestedness is a common pattern of species assemblages in fragmented landscapes. The spatial pattern and ecological drivers of nested communities have been widely explored, but...     

A pilot study to determine the production and health benefits of milking visibly lame cows twice daily compared with three times daily

A randomized clinical trial was conducted on lame cows to study the effect of milking frequency on milk production, lameness prevalence, and body condition score (BCS). At the beginning of the study, the entire herd of lactating Holstein dairy cows was visual locomotion scored (VLS) by 2 trained veterinarians. Lame cows (VLS > 2) were eligible for the study. The initial study population consisted of 270 cows randomly allocated to the three-times-daily milking frequency group (MFG) and 230 cows randomly allocated to the twice-daily MFG. Milking frequencies did not significantly affect average milk production. Cows in the twice-daily MFG had a significant increase in BCS, however, compared with cows in the three-times-daily MFG (P-value < 0.001). In addition, the probability of lameness in cows in the three-times-daily MFG was 36% higher than for cows in the twice-daily milking routine (P-value = 0.006).     

Status of insecticide resistance in Culex pipiens field populations from north-eastern areas of Italy before the withdrawal of OP compounds

BACKGROUND: Heavy and constant use of organophosphorus (OP) larvicides selected Culex pipiens L. resistant populations through two main mechanisms of genetic resistance, the increased activity of detoxifying esterase and the production of alterate acetylcholinesterase‐1 (AChE1) by G119S mutation. The aim of this study was the assessment of the distribution of Cx. pipiens populations resistant to temephos and chlorpyrifos in the north‐eastern regions of Italy and the occurrence of the insensitive AChE in these populations. Data describe the situation in the last years before European legislation prohibited the use of OP larvicides in mosquito control, up until 2007. RESULTS: For the first time a high level of OP resistance in the samples from Ravenna (182‐fold, 80% A4/B4 or A5/B5 esterases and 38.3% Ester⁵), Emilia Romagna region, was detected; therefore, new data from the Veneto and Friuli Venezia Giulia regions were obtained and reinforced existing knowledge about resistance previously studied along the Adriatic coast. Nearby, in the Villa Verucchio locality, the highest (87.5%) AChE1R was found. CONCLUSION: Cx. pipiens resistance esterases A5/B5 and A4/B4 spread southward along the Adriatic coastal plain while OPs were being used in mosquito control, as confirmed by the first molecular screening of the AChE1 gene in these populations. Copyright © 2010 Society of Chemical Industry     

Soil management and traffic effects on infiltration of irrigation water applied using sprinklers

Zero tillage and controlled traffic have been proposed as means for more productive and sustainable irrigated farming. Both practices affect soil infiltration characteristics and, therefore, should have effects on sprinkler irrigation performance. This study compared water infiltration and runoff in three sprinkler irrigation tests performed on an alluvial loam soil at different times during a maize (Zea mays L.)–cotton (Gossypium hirstium L.) rotation under two soil managements: permanent beds with crop residue retention (PB: planting beds maintained unaltered from year to year) and conventional beds with residues incorporated with tillage (CB: disc and chisel ploughing followed by rotavator pass and bed forming every year). Traffic was controlled and two types of furrows were distinguished in both tillage systems: with (+T) and without (−T) wheel traffic. The irrigation tests were performed on maize at full cover, on bare soil just before cotton sowing and on cotton with 50% ground cover. Infiltration and runoff were affected notably by both traffic and soil management. The soil under PB infiltrated more water than under CB, and −T furrows more than +T furrows. Considering the combined treatments, −T furrows in the CB system infiltrated more water than +T furrows in the PB system. A sprinkler irrigation model for simulating water application and soil infiltration and runoff was formulated. The model was used to analyse irrigation performance under infiltration characteristic of the CB and PB systems in trafficked and non-trafficked furrows. Five irrigation performance indicators were used to assess the various combinations of tillage and traffic: Wilkox–Swailes coefficient of uniformity; application efficiency; deep percolation ratio; tail water ratio; and adequacy. The model was used to develop operation diagrams and provided guidelines for making irrigation decisions in the new controlled traffic/permanent bed system and in a standard conventional system.     

Numerical approach to modelling pulse-mode soil flushing on a Pb-contaminated soil

Purpose

Soil flushing can represent a suitable technology in remediation of soils, sediments and sludge contaminated by persistent species (e.g. toxic metal). This paper presents a model specifically developed to evaluate the feasibility of chelating agent-enhanced flushing. The model, here applied to the remediation of real Pb-contaminated soils, was conceived also to simulate an innovative pulse-mode soil flushing technique.

Materials and methods

The soil flushing application was firstly carried out through columns laboratory experiments. Columns were filled with a real Pb-contaminated soil (3,000 mg kg^?1 of dry soil) and flushing was operated in a pulse mode with different chelating agent dosages (3 and 4.3 mmol kg^?1soil). Experimental results were used to calibrate and validate the developed reactive transport model that accounts for transport of ethylenediamine tetraacetic acid (EDTA) and EDTA–Pb chelate complexes, Pb residual concentration on soil and the reduction in permeability by soil dissolution. Determination of hydrodynamic and hydro-dispersive parameters was carried out through a numerical approach incorporating the use of neural network as interpolating function of breakthrough data obtained by a tracer test.

Results and discussion

The EDTA dosage strongly influenced the efficiency in Pb extraction and soil permeability. Cumulative extractions of Pb were found to be 20 and 29 % for the EDTA concentrations of 3 and 4.3 mmol/kg of dry soil, respectively. The soil dissolution caused a significant flow rate decrease, as a consequence of the increase in chelating agent concentration. Therefore the recovery phase duration increased from 738 to 2,080 h. The ability of the model in simulating all the examined phenomena is confirmed by a good fit with experimental results in terms of (a) soil permeability reduction, (b) eluted Pb and (c) residual Pb in the soil.

Conclusions

Results highlighted as the model, supported by a preliminary and careful characterization of the soil, can be useful to assess the feasibility of the flushing treatment (avoiding soil clogging) and to address the choice of the operating parameters (flow rate, chelating agent dosage and application method). On the basis of the present research results, a protocol is suggested for in situ soil pulse–flushing application.     

Advances and challenges in marine conservation in Chile: A regional and global comparison

1. Despite significant progress made in Chile, and globally, in establishing marine protected areas (MPAs), the actual contribution to marine biodiversity conservation needs to be revised, to focus on representativeness and the diversity of tools alongside effective implementation, management, and enforcement.
2. This study makes progress in this direction, describing the most recent advances in marine conservation in Chile and analysing the contribution of the different conservation instruments as well as the distribution of designated areas across ecoregions. Furthermore, it examines the potential contribution of alternative area-based instruments to balance ocean protection. The advances observed in Chile were compared among four South American countries and five leading countries in ocean conservation, analysing protection levels in coastal areas, continental exclusive economic zones, and overseas territories.
3. Data on MPA boundaries and attributes were sourced from the World Database on Protected Areas and complemented the official information on MPAs and territorial user rights for fisheries and for indigenous people in South America.
4. The current level of protection in Chile is among the highest in the world in area coverage and in the proportion of the continental exclusive economic zone assigned to fully protected areas. However, it exhibits the strongest imbalances in the distribution of designated MPAs between coastal and oceanic waters, in comparison with the leading countries and also within South America (Perú, Chile, Argentina, and Uruguay), and among ecoregions.
5. The patterns observed suggest that Chile has advanced, but concentrated, conservation efforts in low-threat, remote ecoregions. There is an urgent need to progress towards high-threat ecoregions, which implies balancing the needs of nature and people. The distribution of ancillary conservation instruments can help double the level of protection in threatened coastal areas, filling gaps in marine conservation and creating an opportunity to progress and diversify conservation strategies.