Within plant distribution of Anthonomus grandis (Coleoptera: Curculionidae) feeding and oviposition damages in cotton cultivars

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Does low-protein diet improve broiler performance under heat stress conditions?

Nutrition for broilers under high temperatures is extremely important for brazilian broiler chicken industry because the amounts of consumed nutrients and environmental temperature have great effects on bird performance and carcass quality. Among diet nutrients, protein has the highest heat increment; thus, during many years, diets with low protein level were recommended in order to reduce heat production in broiler chickens under heat stress. However, reports have shown that low-protein diets have negative effects on broiler performance when environmental temperature is high, because during heat stress, low food intake associated to a low diet protein induce amino acid deficiencies. Other studies have shown that broilers fed low-protein diets increase their energy requirement for maintenance with higher heat production. Thus, with the growth of broiler industry in tropical areas more challenges need to be faced by the farmers. So, both the ambient and nutritional conditions ought to be well managed to avoid negative effects on poultry production once they can affect the metabolism (body heat production under low temperature and body heat dissipation under high temperature) with consequence on poultry performance (meat and eggs).

Ticks' response to feeding on host immunized with glandular extracts of Rhipicephalus sanguineus females fed for 2, 4, and 6 days. I. Inactivity or early degeneration of salivary glands?

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cell Death in Salivary Glands of Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae) Females at Semi-engorged Feeding Stage

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of heat treatment on stainless steel orthodontic wires

This study evaluated the effect of heat treatment on CrNi stainless steel orthodontic archwires. Half of forty archwires of each thickness - 0.014 (0.35 mm), 0.016 (0.40 mm), 0.018 (0.45 mm) and 0.020 (0.50 mm) (totalling 160 archwires) - were subjected to heat treatment while the remainder were not. All of the archwires had their individual thickness measured in the anterior and posterior regions using AutoCad 2000 software before and after compressive and tensile strength testing. The data was statistically analysed utilising multivariance ANOVA at a 5% significance level. All archwires without heat treatment that were subjected to tensile strength testing presented with anterior opening, which was more accentuated in the 0.020 archwires. In the posterior region, the opening produced by the tensile force was more accentuated in the archwires without heat treatment. There was greater stability in the thermally treated archwires, especially those subjected to tensile strength testing, which indicates that the heat treatment of orthodontic archwires establishes a favourable and indispensable condition to preserve the intercanine width.

Evaluating feeding as unconditioned stimulus for conditioning of an endocrine effect in Nile tilapia

This study tested the adequacy of feeding as an unconditioned stimulus (US) to condition an endocrine response (plasma cortisol increase) in the cichlid fish Nile tilapia (Oreochromis niloticus). In a first study, conditioning was confirmed in grouped fish in the only experiment using single-held Nile tilapia. In this test a conditioned stimulus (CS - aeration off) was associated with a stressor (air emersion for 2 min - US). We then assessed whether several events of paired CS-US resulted in a conditioned endocrine response (CR), in this case an increase in plasma cortisol after presentation of the CS only. Before testing feeding as US, the postprandial or social holding condition for feeding effects on cortisol levels was tested. Nile tilapia showed increased cortisol after feeding associated to social context (grouped fish), but not to food only (single-held fish). In a third study, feeding was tested as US in an experiment similar to the first study but an increase in feeding-induced cortisol could not be conditioned. The absence of CR suggests that the stressor affects acquisition of this response, which may be a consequence of stimulus intensity or biological relevance. This study expands the recently reported Pavlovian conditioning paradigm for endocrine response in fish. (C) 2007 Elsevier B.V. All rights reserved.

Structural and cytochemical changes in the salivary glands of the Rhipicephalus (Boophilus) microplus (CANESTRINI, 1887) (Acari : Ixodidae) tick female during feeding

This study describes the morphology of salivary glands of Rhipicephalus (Boophilus) microplus female ticks at beginning of feeding (24-48 h of attachment) and semi-engorged (4-5 days of attachment) to verify the degenerative characteristics of these organs and the secretory phase in which the process begins. At the beginning of feeding, secretion granules had been observed only in the cytoplasm of cells b, c(1), c(2), c(4) (type II acinus) and d (type III acinus), as well as large nuclei with regular and preserved morphology. In the semi-engorged females the acini presented few normal cells, few partially preserved ones, and the remaining ones in several stages of degeneration, that is, with retraction and cytoplasmic vacuolization, and nuclei with chromatin in several stages of condensation, picnotic and/or in fragmentation. In type I acinus and in the excretory ducts of the studied glands, at both feeding stages, no degenerative characteristic was observed. In females of R. (B.) microplus, the salivary glands degenerate asynchronically and precociously when compared with those of others tick's species. (c) 2006 Elsevier B.V. All rights reserved.

Ultrastructure features of the midgut of the female adult Amblyomma cajennense ticks Fabricius, 1787 (Acari: Ixodidae) in several feeding stages and subjected to three infestations

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ontogenetic diet shifts of a Neotropical catfish, Pimelodus maculatus (Siluriformes, Pimelodidae): An ecomorphological approach

This study analyses the ontogenetic diet shifts of a Neotropical catfish, Pimelodus maculatus ( Siluriformes, Pimelodidae), from an ecomorphological standpoint. We collected 241 individuals in the Piracicaba River ( Brazil) and, in the laboratory, seven morphometric variables were recorded from each specimen: standard length (SL), body depth, head length, snout length, eye diameter, mouth height and mouth width. After standardizing these measurements ( as a proportion of SL), linear regressions were run to determine whether their growth was isometric or allometric in relation to SL. The diet analysis shows that the main food item for fish in the smaller size classes is aquatic insects, while the largest individuals feed mainly on other fish. As the great majority of the morphometric variables analyzed showed isometric growth as a function of SL - which means that these fish do not change their shape significantly during their lives - the ontogenetic diet shifts may be seen as a consequence of the absolute size increment of their mouth gape, which allows individuals to maximize their energetic gain by ingesting larger prey with a higher caloric content.

Diet and feeding of fish from Grande River, located below the Volta Grande Reservoir, MG-SP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Acerola's pectin methylesterase: studies of heat inactivation

The effect of temperature on the activity of acerola's pectin methylesterase (PME) was studied to determine its heat-inactivation. The acerola's pectin methylesterase (PME; EC: 3.1.1.11) is very stable at 50 degrees C (10% loss of activity in 100 min) and needed 110 min for its inactivation at 98 degrees C. These values are much higher than the ones required for inactivation of the citrus PME, that has been reported as being equal to 1 min at 90 degrees C. Heat-inactivation of PME was shown to be nonlinear, suggesting the presence of fractions of PME with differing heat-stabilities. The times to inactive the enzyme at 98, 102 and 106 degrees C were 110, 10 and 2.17 min, respectively. The Z value (the rise in temperature necessary to observe a ten times faster heat-inactivation) was 4.71 degrees C. (C) 2000 Elsevier B.V. Ltd. All rights reserved.

Thermal diffusivity analysis of doped poly(methyl-methacrylate) with electron donor and acceptor molecules

A computer-assisted method for analysing photoacoustic spectra has been developed in the Windows(TM) environment with the use of an easy graphical interface, the computer simulation was carried out with the aim of using the entire expression of the Rosencwaig-Gersho theory, thus permitting multiple applications. The simulation was applied to a system that mimics the electron transfer process in which the concentration of octaethylporphin donor molecules was constant whereas the concentration of duroquinone and 2,3-dichloro-5,6-dicyano-1, l-benzoquinone acceptor molecules varied. The increment of the acceptor concentration influenced the photoacoustic amplitude and phase signals. In the phase signal a significant shift to smaller values was observed, denoting a faster heat generation. The analysis of the photoacoustic signal enabled the determination of the thermal diffusivity, the result obtained through the simulation was about (7 +/- 1) x 10(-7) m(2) s(-1) indicating that changes in the photoacoustic phase signals were due to the electron transfer process rather than changes in the thermal properties of the sample.

Built to Bite: Feeding Kinematics, Bite Forces, and Head Shape of a Specialized Durophagous Lizard, Dracaena Guianensis (Teiidae)

Most lizards feed on a variety of food items that may differ dramatically in their physical and behavioral characteristics. Several lizard families are known to feed upon hard-shelled prey (durophagy). Yet, specializations toward true molluscivory have been documented for only a few species. As snails are hard and brittle food items, it has been suggested that a specialized cranial morphology, high bite forces, and an adapted feeding strategy are important for such lizards. Here we compare head and skull morphology, bite forces, and feeding kinematics of a snail-crushing teiid lizard (Dracaena guianensis) with those in a closely related omnivorous species (Tupinambis merianae). Our data show that juvenile D. guianensis differ from T. merianae in having bigger heads and greater bite forces. Adults, however, do not differ in bite force. A comparison of feeding kinematics in adult Dracaena and Tupinambis revealed that Dracaena typically use more transport cycles, yet are more agile in manipulating snails. During transport, the tongue plays an important role in manipulating and expelling shell fragments before swallowing. Although Dracaena is slow, these animals are very effective in crushing and processing hard-shelled prey. J. Exp. Zool. 317A:371381, 2012. (c) 2012 Wiley Periodicals, Inc.

Experimental analysis of heat recoveries with heat pipes operating in low inclination angle

Heat recovery devices are important in the optimization of thermal systems, since they can be used to reduce thermal losses to the environment. The use of heat pipes in these types of equipment can provide heat recoveries of higher efficiency, since both fluid flows are external and there are less contamination risks between the hot and cold fluids. The objective of this work is to study a heat recovery unit constructed with heat pipes and mainly, to analyze the influence of the inclination of the heat pipes on the performance of the equipment. For this analysis, a heat recovery unit was constructed which possesses 48 finned heat pipes in triangular geometry, the evaporator and condenser being of the same length. This unit was tested in an air-air system simulating a heat recovery process in which heat was supplied to the hot fluid by electrical resistances. The results have shown that there exists an inclination at which the system has a better performance, but for higher inclinations there is no significant increase of the efficiency of the system. This paper also presents the influence of inclination of heat pipes on effectiveness and NTU parameters which are important in heat exchanger design.

Heat treatment and inactivation of trypsin-chymotrypsin inhibitors and lectins from beans (Phaseolus vulgaris L.)

This work investigates some factors affecting the inactivation of common bean trypsin inhibitor and phytohemagglutin. Trypsin inhibitor activity was totally stable to heat treatment (30 min, 97C) in the total protein extract, albumin or globulin fraction. Heat treatment of the whole beans easily inactivated the inhibitor. Heat resistance of trypsin inhibitor was intermediate in the bean flour which received the same heat treatment. Independent of sample, the inhibitor was very stable to heat treatment at neutral and acidic pH and labile under strong alkaline conditions. Heating for 30 min in boiling water at pH 12 resulted in complete inactivation of the trypsin inhibitor. Autoclaving (121C) soaked whole beans and flour for 5 min inactivated 55% of the trypsin inhibitor activity in the soaked flour and 75% in the whole beans. After autoclaving 20 min, inactivation of trypsin inhibitor was about 65% in the flour and 80% in the whole beans. The phytohemagglutinin (lectin) activity was totally destroyed in the autoclaved beans after 5 min and in the flour after 15 min.