Testing heterogeneous anchoring and shift effect in double-bounded models: The case of recreational fishing in Tasmania

This paper explores the extent and nature of anchoring and shift effects in a double-bounded contingent valuation of recreational fishing in Tasmania’s inshore saltwater fishery. In particular we model the situation where respondents, when answering the second valuation question, evaluate the bid amount partly with reference to the size of the first bid amount. The estimates of the coefficients and mean WTP for a day of fishing are compared across different contingent valuation models, including a single-bounded model, a conventional double-bounded model and models that control anchoring and exogenous shift effects in both homogeneous and heterogeneous forms. Overall we find consistent evidence of anchoring, but mixed evidence of a shift effect. Results show that both males and females anchor in the same way, but that respondents who have a mainstream view of what recreational fishing represents anchor more strongly than those whose view of fishing is not mainstream. The estimated mean WTP for a day’s recreational fishing is consistently higher in all models which account for bias in responses than in either the single-bounded or double-bounded models. We indicate the possibility that anchoring behaviour may be more complex than is captured in our models and suggest that this needs to be addressed if the results of contingent valuations are to reliably inform resource allocation decisions and recreational fishing management.Contingent valuation, anchoring bias, shift effect, heterogeneity, recreational fishing, Environmental Economics and Policy, C35, Q26,

PRICING AND USE OF DROUGHT-STRESSED AND IMMATURE CORN AS SILAGE FOR BEEF CATTLE

Demand and Price Analysis,

Economically Optimal Distiller Grain Inclusion in Beef Feedlot Rations: Recognition of Omitted Factors

With the rapid expansion of the ethanol industry, the feeding landscape familiar to the feedlot industry is changing. While concerns regarding rising corn prices persist, many within the industry are looking at distiller’s grains, a by-product of ethanol production, to serve as a feed substitute. The question remains as to what extent these two feed sources are substitutable. The purpose of this study is to identify the economically optimal inclusion rate of distiller’s grains in beef feedlot rations, considering an array of often omitted factors. Most currently prevailing recommendation rates are strictly biologically based and frequently reference only one feeding trial. Unique economic factors considered in this research include the impact of by-product inclusion rates on animal performance (utilizing recently conducted meta-analysis from 17 relevant feeding trials), enhanced likelihood of death loss from heightened sulfur content, and manure disposal costs. Results indicate that excluding these factors can significantly impact optimal inclusion levels and that reliance on a single or few feeding trials may greatly bias results.distiller’s grains, livestock rations, manure disposal cost,

ECONOMICS OF ALTERNATIVE STOCKING DENSITIES FOR DIRECT-SEEDED CENTRAL MICHIGAN ALFALFA PASTURES

A framework which permits estimation of economically optimal stocking rates for alternative economic parameters and alfalfa forage availability was developed and applied to a controlled grazing experiment conducted with Holstein steers (243 kg) placed on direct seeded alfalfa pastures in Central Michigan. Responses of ADG to alternative levels of forage availability per standard livestock unit (FA) were summarized by a quadratic function and the associated gains/ha were calculated. The ADG decreased as standard stocking rate (SSR; SLU/ha) increased except for the combination of the lowest observed SSR and highest FA, where ADG was curvilinear as SSR increased. The trend for gain/ha was curvilinear for all FA. The SSR which maximized gain/ha increased with FA and was greater than that which maximized ADG. Net returns to fixed resources(NRFR)/ha ($/ha)were calculated for alternative SSR and the economically optimal SSR were identified under various levels of herbage mass (kg/d). The SSR's which maximized NRFR were between the SSR's which maximized ADG and gain/ha. The magnitude of the sale price discount for heavier weight calves (slide) influenced the economically optimal SSR and the sensitivity of net return to SSR. The economically optimal SSR increased as slide increased because animals stocked under higher SSR weighed less off pasture and therefore received less price discount.Crop Production/Industries,

Economically Optimal Distiller Grain Inclusion in Beef Feedlot Rations: Recognition of Omitted Factors

With the rapid expansion of the ethanol industry, the feeding landscape familiar to the feedlot industry is changing. While concerns regarding rising corn prices persist, many within the industry are looking at distillers grains, a by-product of ethanol production, to serve as a feed substitute. The question remains as to what extent these two feed sources are substitutable. The purpose of this study is to identify the economically optimal inclusion rate of distillers grains in beef feedlot rations, considering an array of often omitted factors. Most currently prevailing recommendation rates are strictly biologically based and frequently reference only one feeding trial. Unique economic factors considered in this research include the impact of by-product inclusion rates on animal performance (utilizing recently conducted meta-analysis from 17 relevant feeding trials), enhanced likelihood of death loss from heightened sulfur content, and manure disposal costs. Results indicate that excluding these factors can significantly impact optimal inclusion levels and that reliance on a single or few feeding trials may greatly bias results.Livestock Production/Industries,

Influence of Corn Moisture, Protein Concentration and Monensin on Digestion by Feedlot Steers

Animal Scienc

Associative Effects in the Ruhinant Animal

Animal Nutritio

Analysis of the first gigantic jet recorded over continental North America

[1] Two low-light cameras near Marfa, Texas, recorded a gigantic jet over northern Mexico on 13 May 2005 at approximately 0423:50 UTC. Assuming that the farthest of two candidate storm systems was its source, the bright lower channel ended in a fork at around 50–59 km height with the very dim upper branches extended to 69–80 km altitude. During the time window containing the jet, extremely low frequency magnetic field recordings show that there was no fast charge moment change larger than 50 coulomb times kilometers (C km) but there was a larger and slower charge moment change of 520 C km over 70 ms. The likely parent thunderstorm was a high-precipitation supercell cluster containing a persistent mesocyclone, with radar echo tops of at least 17 km. However, photogrammetric analysis suggests that the gigantic jet occurred over the forward flank downdraft region with echo tops of 14 km. This part of the supercell may have had an inverted-polarity charge configuration as evidenced by positive cloud-to-ground lightning flashes (+CG) dominating over negative flashes (-CG), while -CGs occurred under the downwind anvil. Four minutes before the gigantic jet, -CG activity practically ceased in this area, while +CG rates increased, culminating during the 20 s leading up to the gigantic jet with four National Lightning Detection Network–detected +CGs. A relative lull in lightning activity of both polarities was observed for up to 1.5 min after the gigantic jet. The maturing storm subsequently produced 30 sprites between 0454 and 0820 UTC, some associated with extremely large impulse charge moment change values.Peer ReviewedPostprint (published version

Susceptibility of adult cat fleas (Siphonaptera: Pulicidae) to insecticides and status of insecticide resistance mutations at the Rdl and knockdown resistance loci

This is an Open Access article. © 2015 The Author(s). Published by Springer Berlin Heidelberg.The susceptibility of 12 field-collected isolates and 4 laboratory strains of cat fleas, Ctenocephalides felis was determined by topical application of some of the insecticides used as on-animal therapies to control them. In the tested field-collected flea isolates the LD50 values for fipronil and imidacloprid ranged from 0.09 to 0.35 ng/flea and 0.02 to 0.19 ng/flea, respectively, and were consistent with baseline figures published previously. The extent of variation in response to four pyrethroid insecticides differed between compounds with the LD50 values for deltamethrin ranging from 2.3 to 28.2 ng/flea, etofenprox ranging from 26.7 to 86.7 ng/flea, permethrin ranging from 17.5 to 85.6 ng/flea, and d-phenothrin ranging from 14.5 to 130 ng/flea. A comparison with earlier data for permethrin and deltamethrin implied a level of pyrethroid resistance in all isolates and strains. LD50 values for tetrachlorvinphos ranged from 20.0 to 420.0 ng/flea. The rdl mutation (conferring target-site resistance to cyclodiene insecticides) was present in most field-collected and laboratory strains, but had no discernible effect on responses to fipronil, which acts on the same receptor protein as cyclodienes. The kdr and skdr mutations conferring target-site resistance to pyrethroids but segregated in opposition to one another, precluding the formation of genotypes homozygous for both mutations.Peer reviewedFinal Published versio