Genetic compatibility affects division of labor in the argentine ant linepithema humile.

Division of labor is central to the organization of insect societies. Within-colony comparisons between subfamilies of workers (patrilines or matrilines) revealed genetic effects on division of labor in many social insect species. Although this has been taken as evidence for additive genetic effects on division of labor, it has never been experimentally tested. To determine the relative roles of additive and nonadditive genetic effects (e.g., genetic compatibility, epistasis, and parent-of-origin imprinting effects) on worker behavior, we performed controlled crosses using the Argentine ant Linepithema humile. Three of the measured behaviors (the efficiency to collect pupae, the foraging propensity, and the distance between non-brood-tenders and brood) were affected by the maternal genetic background and the two others (the efficiency to feed larvae and the distance between brood-tenders and brood) by the paternal genetic background. Moreover, there were significant interactions between the maternal and paternal genetic backgrounds for three of the five behaviors. These results are most consistent with parent-of-origin and genetic compatibility effects on division of labor. The finding of nonadditive genetic effects is in strong contrast with the current view and has important consequences for our understanding of division of labor in insect societies.

Effects of Crypthecodiniumcohnii, Chlorela spp. e Isochrysisgalbana addition to milk replacer on goat kids and lamb growth.

The effects of Crypthecodinium cohnii (Cryp.), Chlorela spp. (Chlo.) and Isochrysis galbana (Iso.) addition to milk replacer on goat kids and lambs growth were evaluated. About 80 Majorera goat kids (males and females) and 80 Canarian sheep lambs were randomly assigned into four different groups (by specie) according to diet. Control groups were fed with a commercial milk replacer at 16% (w/w); Cryp. groups received a commercial milk replacer (15.1% w/w) supplemented with 9 g of a paste of C. cohnii; Chlo. groups received a commercial milk replacer (15.1% w/w) supplemented with 9 g of a paste of Chlorela spp.; Iso. groups received a commercial milk replacer (15.1% w/w) supplemented with 9 g of a paste of I. galbana. After colostrum period, animals were individually bottle-fed twice daily (8 am and 8 pm) ad libitum with the corresponding diet until day 60 of life. Animals were weighted every week at 8 am and liquid diet intake was recorded weekly. No effects of microseaweed addition were observed, neither growth nor milk replacer intake.

The effect of colostrum source (goat vs. sheep) and timing of the first colostrum feeding (2h vs. 14h after birth) on body weight and immune status of artificially reared newborn lambs.

Several factors can affect lamb body weight (BW) and immune status during the first days of life, including colostrum source and timing of the first colostrum feeding. The aim of this study was to evaluate the effects of colostrum source (goat or sheep) and timing of the first colostrum feeding (2 or 14h after birth) on lamb BW and immune status. In this study, 40 lambs were removed from their dams at birth and randomly assigned into 4 groups of 10 lambs each. Lambs were subsequently fed at 2 or 14h after birth with goat or sheep colostrum. Blood samples and BW recording were performed before feeding. Blood plasma was used to measure the immunoglobulin concentration (IgG and IgM), chitotriosidase activity, and complement system activity (total and alternative pathways). In general, no differences in any of the measured variables were observed among the 4 groups, indicating that neither colostrum source nor timing of the first colostrum feeding had an effect on these variables. These findings may improve management on lamb farms that raise animals under artificial conditions, because our results indicate that it is not necessary to feed colostrum to lambs immediately after birth and that goat colostrum may be used to feed newborn lambs.

Automatització d’una fàbrica de pinso

Les produccions ramaderes en el seu conjunt no es podrien atendre en el món actual sensela participació de la indústria del pinso compost. L’alternativa de treballar en base a pinsosimple o senzillament amb cereals o altres primeres matèries individuals, faria inviablel’abastiment en qualitat i quantitat del que es consumeix.La realització de pinso compost és el resultat de la barreja de variades substànciesalimentàries, sals minerals i fàrmacs per a la nutrició del bestiar.Les fàbriques de pinso aglutinen diverses explotacions agràries, garantint diàriament un treballcontinu sense grans fluctuacions, una dosificació exacta depenent de la recepta que hagiprogramat el veterinari i flexibilitat davant els canvis.Aquestes fàbriques requereixen de maquinària més precisa per fer front a les molt variades receptesnutricionals depenent del tipus de bestiar i de l’època estacional.La dimensió de les fàbriques també serà més gran, per poder atendre la major demanda decomandes i assegurar una producció de qualitat.Moltes fàbriques de pinso són velles o provenen d’antigues explotacions ramaderesreconvertides, les quals d’acord amb l’actual necessitat de control de qualitat, efectivitat irapidesa s’han modernitzat o s’estan reciclant, car el propi mercat i competència els estàprecipitant a fer-ho.Una fàbrica moderna de pinso és una planta de processos que incorpora tecnologies defabricació i control, iguals que qualsevol indústria.S’ha de dissenyar per produir pinso compost de forma competitiva i tindre en tot momentcapacitat per controlar els seus processos, així com assegurar la qualitat del producte final,tant a nivell nutricional com el sanitari.Això s’ha de realitzar amb el màxim nivell de seguretat pels operaris, alhora que s’elimininels efectes de contaminació ambiental, com la pols i el soroll.Amb l’automatització de la fàbrica ja no es repetiran les errades per l’accionament demotors, malmetent una dosificació i perdent un temps molt valuós

Disseny de l'automatització d'una fàbrica de pinsos per aviram

Ens trobem davant una fàbrica de pinsos per aviram sense cap tipus de controlautomatitzat. Actualment totes les actuacions són semiautomàtiques i amb necessitat de personal. La fàbrica té tots els elements mecànics necessaris per poder funcionar, per tant, només falta algun element elèctric per automatitzar la planta i un PC per poder implementar un SCADA.Els objectius principals a portar a terme serien: obtenir millor producte, més homogeni i poder augmentar el volum de la producción diària, prescindir de personal per reduir costos i així la producció sigui més rendible, preparar la planta per a futures ampliacions

Desenvolupament d'un node sensor sense fils autoalimentat. Mòdul piezo-magnètic

En aquest projecte es pretén implementar un dispositiu capaç de ser auto-suficient i no dependre de cap tipus de pila, bateria o fil elèctric que l’abasteixi d’energia elèctrica. El dispositiu recol·lectarà la energia magnètica generada per la corrent elèctrica a un fil i la transformarà en energia elèctrica, que serà emmagatzemada per el seu posterior ús. A demès, aquest projecte s’ha desenvolupat en col·laboració amb un segon projecte, dintre del qual s’implementarà una xarxa de sensors, mitjançant el protocol MIWI. Aquest projecte es divideix en tres grans blocs. El primer bloc del projecte serà una introducció teòrica de tots els coneixements relacionats amb el concepte d’energy harvesting i els mecanismes físic implicats. Al segon bloc podrem veure com s’han realitzat els càlculs, simulacions i posada en marxa, dels diferents elements que formaran el dispositiu recol·lector d’energia. Per últim en el tercer bloc veurem el prototip ja implementat. Es valoraran els resultats obtinguts, i es veuran els temps que necessitarà per alimentar al microcontrolador.

Feeding and the Equilibrium Feeder Animal Price-Weight Schedule, June 2005

The feeder animal price is a derivative in the sense that its value depends upon the price of animals for the consumption market. It also depends upon the biological growth technology and feed costs. Daily maintenance costs are of particular interest to the husbander because they can be avoided through accelerated feeding. In this paper, the optimal feeding path under equilibrium feeder animal prices is established. This analysis is used to gain a better understanding of feeding decisions, regulation in feedstuff markets, and the consequences of genetic innovations. It is shown that days on feed can increase or decrease with a genetic innovation or other improvement in feed conversion efficiency. The structure of comparative prices for feeder animals at different weights, the early slaughter decision, and equilibrium in feeder animal markets are also developed. Feeder animal prices can increase over a weight interval if biological feed efficiency parameters are low over the interval.

Final Report for the Iowa Livestock Industry Waste Characterization and Methane Recovery Information Dissemination Project, 2003

The Iowa livestock industry generates large quantities of manure and other organic residues; composed of feces, urine, bedding material, waste feed, dilution water, and mortalities. Often viewed as a waste material, little has been done to characterize and determine the usefulness of this resource. The Iowa Department of Natural Resources initiated the process to assess in detail the manure resource and the potential utilization of this resource through anaerobic digestion coupled with energy recovery. Many of the pieces required to assess the manure resource already exist, albeit in disparate forms and locations. This study began by interpreting and integrating existing Federal, State, ISU studies, and other sources of livestock numbers, housing, and management information. With these data, models were analyzed to determine energy production and economic feasibility of energy recovery using anaerobic digestion facilities on livestock faxms. Having these data individual facilities and clusters that appear economically feasible can be identified specifically through the use of a GIs system for further investigation. Also livestock facilities and clusters of facilities with high methane recovery potential can be the focus of targeted educational programs through Cooperative Extension network and other outreach networks, providing a more intensive counterpoint to broadly based educational efforts.

The Long-Run Impact of Corn-Based Ethanol on the Grain, Oilseed, and Livestock Sectors: A Preliminary Assessment, November 2006

The ongoing growth of corn-based ethanol production raises some fundamental questions about what impact continued growth will have on U.S. and world agriculture. Estimates of the long-run potential for ethanol production can be made by calculating the corn price at which the incentive to expand ethanol production disappears. Under current ethanol tax policy, if the prices of crude oil, natural gas, and distillers grains stay at current levels, then the break-even corn price is $4.05 per bushel. A multi-commodity, multi country system of integrated commodity models is used to estimate the impacts if we ever get to $4.05 corn. At this price, corn-based ethanol production would reach 31.5 billion gallons per year, or about 20% of projected U.S. fuel consumption in 2015. Supporting this level of production would require 95.6 million acres of corn to be planted. Total corn production would be approximately 15.6 billion bushels, compared to 11.0 billion bushels today. Most of the additional corn acres come from reduced soybean acreage. Wheat markets would adjust to fulfill increased demand for feed wheat. Corn exports and production of pork and poultry would all be reduced in response to higher corn prices and increased utilization of corn by ethanol plants. These results should not be viewed as a prediction of what will eventually materialize. Rather, they indicate a logical end point to the current incentives to invest in corn-based ethanol plants.

Emerging Biofuels: Outlook of Effects on U.S. Grain, Oilseed, and Livestock Markets, 2007

Projections of U.S. ethanol production and its impacts on planted acreage, crop prices, livestock production and prices, trade, and retail food costs are presented under the assumption that current tax credits and trade policies are maintained. The projections were made using a multi-product, multi-country deterministic partial equilibrium model. The impacts of higher oil prices, a drought combined with an ethanol mandate, and removal of land from the Conservation Reserve Program (CRP) relative to baseline projections are also presented. The results indicate that expanded U.S. ethanol production will cause long-run crop prices to increase. In response to higher feed costs, livestock farmgate prices will increase enough to cover the feed cost increases. Retail meat, egg, and dairy prices will also increase. If oil prices are permanently $10-per-barrel higher than assumed in the baseline projections, U.S. ethanol will expand significantly. The magnitude of the expansion will depend on the future makeup of the U.S. automobile fleet. If sufficient demand for E-85 from flex-fuel vehicles is available, corn-based ethanol production is projected to increase to over 30 billion gallons per year with the higher oil prices. The direct effect of higher feed costs is that U.S. food prices would increase by a minimum of 1.1% over baseline levels. Results of a model of a 1988-type drought combined with a large mandate for continued ethanol production show sharply higher crop prices, a drop in livestock production, and higher food prices. Corn exports would drop significantly, and feed costs would rise. Wheat feed use would rise sharply. Taking additional land out of the CRP would lower crop prices in the short run. But because long-run corn prices are determined by ethanol prices and not by corn acreage, the long-run impacts on commodity prices and food prices of a smaller CRP are modest. Cellulosic ethanol from switchgrass and biodiesel from soybeans do not become economically viable in the Corn Belt under any of the scenarios. This is so because high energy costs that increase the prices of biodiesel and switchgrass ethanol also increase the price of cornbased ethanol. So long as producers can choose between soybeans for biodiesel, switchgrass for ethanol, and corn for ethanol, they will choose to grow corn. Cellulosic ethanol from corn stover does not enter into any scenario because of the high cost of collecting and transporting corn stover over the large distances required to supply a commercial-sized ethanol facility.

Efeito da densidade de ninfas de Aphis gossypii Glover, 1877 (Hemiptera, Aphididae) no consumo alimentar e aspectos biológicos de Orius insidiosus (Say, 1832) (Hemiptera, Anthocoridae)

Effect of ninfal density of Aphis gossypii Glover, 1877 (Hemiptera, Aphididae) on feed consumption and biological aspects of Orius insidiosus (Say, 1832) (Hemiptera, Anthocoridae). The influence of different densities of A. gossypii (10, 20, 30, 40, 50, 60 nymphs/day) on consumption rate, development time, survival, and reproduction of Orius insidiosus (Say, 1832) was investigated. The trials were carried out in climatic chamber at 25 ± 1 °C, 70±10% RH, and photoperiod 12:12h (L:D). Consumption rates of nymphs and adults increased under a linear form as the densities of aphids increased. Development time was longest when reared in 10 nymphs density (15.4 days). Nymphal survival was different under the densities of A. gossypii and no significant difference for the periods of preoviposition (4.8 days) and oviposition (8.9 days) were found. The oviposition increased with the prey densities (2.00, 11.33, 10.67, 21.30, 17.89 and 53.38 eggs), as well as the viability: 0.00, 52.49, 57.86, 58.14, 50.11 and 72.89%, respectively. Nymphs of A. gossypii as prey were suitable for the complete development of O. insidiosus.

Comportamento de parasitismo de Trichogramma atopovirilia Oatman & Platner e Trichogramma pretiosum Riley (Hymenoptera, Trichogrammatidae) em posturas de Spodoptera frugiperda (J. E. Smith) (Lepidoptera, Noctuidae)

The parasitism behavior of Trichogramma atopovirilia and T. pretiosum in Spodoptera frugiperda eggs was evaluated focusing on the features related to the associative learning (alpha conditioning) and recognition of the egg parasitized by the female after the first oviposition experience. Females of both species were observed to recognize the parasitized egg, which takes place after the female drills into the host egg. Following oviposition, 43.59% and 67.53 of females began to feed with an average feeding time of 73.26 ± 11.57 and 64.04 ± 7.05 seconds for T. atopovirilia and T. pretiosum, respectively. The time elapsed in each step of the parasitism behavior significantly decreased after the first oviposition experience, with a trend to stabilize after the 2nd or 3rd egg parasitized, indicating associative learning in these Trichogramma species.

The sand rat, Psammomys obesus, develops type 2 diabetic retinopathy similar to humans.

PURPOSE: Diabetic retinopathy (DR) is a leading cause of blindness, yet pertinent animal models are uncommon. The sand rat (Psammomys obesus), exhibiting diet-induced metabolic syndrome, might constitute a relevant model. METHODS: Adult P. obesus (n = 39) were maintained in captivity for 4 to 7 months and fed either vegetation-based diets (n = 13) or standard rat chow (n = 26). Although plant-fed animals exhibited uniform body weight and blood glucose levels over time, nearly 60% of rat chow-raised animals developed diabetes-like symptoms (test group). Animals were killed, and their eyes and vitreous were processed for immunochemistry. RESULTS: Compared with plant-fed animals, diabetic animals showed many abnormal vascular features, including vasodilation, tortuosity, and pericyte loss within the blood vessels, hyperproteinemia and elevated ratios of proangiogenic and antiangiogenic growth factors in the vitreous, and blood-retinal barrier breakdown. Furthermore, there were statistically significant decreases in retinal cell layer thicknesses and densities, accompanied by profound alterations in glia (downregulation of glutamine synthetase, glutamate-aspartate transporter, upregulation of glial fibrillar acidic protein) and many neurons (reduced expression of protein kinase Cα and Cξ in bipolar cells, axonal degeneration in ganglion cells). Cone photoreceptors were particularly affected, with reduced expression of short- and mid-/long-wavelength opsins. Hypercaloric diet nondiabetic animals showed intermediate values. CONCLUSIONS: Simple dietary modulation of P. obesus induces a rapid and severe phenotype closely resembling human type 2 DR. This species presents a valuable novel experimental model for probing the neural (especially cone photoreceptor) pathogenic modifications that are difficult to study in humans and for screening therapeutic strategies.

A review of evolution of oviposition guilds in the Bruchidae (Coleoptera)

Three guilds of bruchid beetles oviposit on seeds at different times and in different ways, i. e., in these guilds some species only oviposit on fruits while on the plant (Guild A), other species only oviposit on seeds exposed in fruits while still on the plant (Guild B) and some only oviposit on seeds once they are exposed on the substrate (Guild C). It has been established that one plant species may be oviposited upon by all three guilds, some only by two guilds and some by only one guild. Before and after the inception of this concept many papers have been published that seem to establish that early oviposition behavior of bruchids was probably onto fruits where they burrowed through the fruit wall and fed on seeds (Guild A). Then, as evolution of the fruits developed for dispersal of seeds and possible escape from bruchid predation, bruchids developed to feed in seeds in various other ways (Guilds B and C). Our data show that about 78% of extant bruchids oviposit on fruits, and the other 22% with behavior of Guilds B and C. A review of these papers and new data on oviposition guilds and bruchid evolution are presented and discussed here.

Study of the combined radial post-feeding dispersion of the blowflies Chrysomya megacephala (Fabricius) and C. albiceps (Wiedemann) (Diptera, Calliphoridae)

Blowflies use discrete and ephemeral substrates to feed their larvae. After they run out of food, the larvae begin to disperse in order to find adequate places for pupation or additional food sources, a process named post-feeding larval dispersion. Some important aspects of this process were studied in a circular arena allowing the combined radial post-feeding dispersion from the center of the arena of C. albiceps and C. megacephala larvae. To determine the location of each pupa, the arena was divided in 72 identical sections starting from the center. The distance from the center, the depth and weight of each pupa were evaluated. Statistical tests were done to verify the relation between weight, depth and distance for pupation. From the total an average of 976 larvae released (488 for each species) were collected considering both experiments 456 C. megacephala pupae and 488 of C. albiceps. This demonstrates that C. albiceps probably preyed on 32 C. megacephala larvae during post-feeding dispersion. The study of this dispersion process can be used to estimate the postmortem interval (PMI) of human cadavers in legal medicine.