Deoxynivalenol: Mechanisms of action and its effects on various terrestrial and aquatic species.

Deoxynivalenol, a type B trichothecene mycotoxin produced by Fusarium species of fungi, is a ubiquitious contaminant of cereal grains worldwide. Chronic, low dose consumption of feeds contaminated with DON is associated with a wide range of symptoms in terrestrial and aquatic species including decreased feed intake and feed refusal, reduced weight gain, and altered nutritional efficiency. Acute, high dose exposure to DON may be associated with more severe symptoms such as vomiting, diarrhea, intestinal inflammation and gastrointestinal hemorrhage.

Development of a microplate method for the determination of hepatic UDP-glucuronosyltransferase activity in rainbow trout (Oncorhynchus mykiss) and Nile tilapia (Oreochromis niloticus).

Hepatic glucuronidation represents an important phase II biotransformation reaction in both mammals and fish. The kinetic characteristics of uridine 5'-diphosphate (UDP) glucuronosyltransferases (UDPGTs) in rainbow trout liver microsomes were examined using p-nitrophenol (p-NP) as an aglycone and UDP-glucuronic acid (UDPGA) as a glucuronyl donor according to an existing protocol. The kinetic data obtained with varying concentrations of p-NP best fit the Hill equation and UDPGT activity was successfully induced following an i.

Apparent Digestibility of Macronutrients and Fatty Acids from Microalgae ( sp.) Fed to Rainbow Trout (): A Potential Candidate for Fish Oil Substitution.

Aquaculture feed formulation has recently turned its focus to reduce the reliance on marine-derived resources and utilise alternative feedstuffs, as an approach to improve the environmental sustainability of the aquaculture sector. The fish oil market is highly volatile, and availability of this commodity is continuously decreasing for use in aquaculture. Currently, a growing number of commercial efforts producing microalgae are providing omega 3-rich oil for sustainable aquaculture feed.

Global metabolic responses of the lenok (Brachymystax lenok) to thermal stress.

High temperature is a powerful stressor for fish living in natural and artificial environments, especially for cold water species. Understanding the impact of thermal stress on physiological processes of fish is crucial for better cultivation and fisheries management. However, the metabolic mechanism of cold water fish to thermal stress is still not completely clear.

Size, growth, and density data for shallow-water sea urchins from Mexico to the Aleutian Islands, Alaska, 1956-2016.

Size, growth, and density have been studied for North American Pacific coast sea urchins Strongylocentrotus purpuratus, S. droebachiensis, S. polyacanthus, Mesocentrotus (Strongylocentrotus) franciscanus, Lytechinus pictus, Centrostephanus coronatus, and Arbacia stellata by various workers at diverse sites and for varying lengths of time from 1956 to present.

Mathematical descriptions of indeterminate growth.

Two models were derived in an effort to better describe the indeterminate nature of growth exhibited by ectotherms. The models are characterized by their non-sigmoidal shape and are based on three assumptions: quantity of growth machinery works at a rate dependent on feed intake; the relationship between growth rate and intake level follows the law of diminishing returns; and growth is irreversible. The Michaelis-Menten and Mitscherlich equations are used in their formulation.

Effects of Wheat Naturally Contaminated with Fusarium Mycotoxins on Growth Performance and Selected Health Indices of Red Tilapia (Oreochromis niloticus × O. mossambicus).

An 8-week feeding trial was conducted to examine effects of wheat naturally contaminated with Fusarium mycotoxins (deoxynivalenol, DON 41 mg·kg(-1)) on growth performance and selected health indices of red tilapia (Oreochromis niloticus × O. mossambicus; initial weight = 4.3 g/fish).

Dietary fatty acid composition and the homeostatic regulation of mitochondrial phospholipid classes in red muscle of rainbow trout (Oncorhynchus mykiss).

Although dietary lipid quality markedly affects fatty acid (FA) composition of mitochondrial membranes from rainbow trout red muscle (Oncorhynchus mykiss), mitochondrial processes are relatively unchanged. As certain classes of phospholipids interact more intimately with membrane proteins than others, we examined whether specific phospholipid classes from these muscle mitochondria were more affected by dietary FA composition than others. To test this hypothesis, we fed trout with two diets differing only in their FA composition: Diet 1 had higher levels of 18:1n-9 and 18:2n-6 than Diet 2, while 22:6n-3 and 22:5n-6 were virtually absent from Diet 1 and high in Diet 2.

Nutrient deposition partitioning and priorities between body compartments in two size classes of rainbow trout in response to feed restriction.

Adaptations in growth dynamics in fish, i.e. how fish prioritise tissue accretion between organs, remains poorly understood.

The actions of in ovo cortisol on egg fertility, embryo development and the expression of growth-related genes in rainbow trout embryos, and the growth performance of juveniles.

Rainbow trout (Oncorhynchus mykiss) oocytes were incubated for 3 hr in ovarian fluid alone (CC), or cortisol-enriched ovarian fluid [100 or 1,000 ng ml(-1) (CL and CH, respectively)], after which they were fertilized; the growth and development of the embryos reared from these oocytes was monitored until first feed, and the juveniles were monitored for 9 months. The hatching rates of the CH group were significantly reduced, but the overall survival as measured at 40-week post-fertilization was similar in the three treatment groups. In addition, significant apparently biphasic changes relative to the CC group were found in the expression of some key growth-related genes in the CL and CH treatment groups, particularly IGF-1, IGF-2, GH1, GH2, GH receptors, and thyroid hormone receptors (TRα and TRβ).

A mechanistic model of nutritional control of protein synthesis in animal tissues.

Regulation of mRNA translation has been held responsible for effects of diet, age, alcohol, hormones, hibernation, disease and hypoxia on protein synthesis in animal tissues. Dietary effects are due to concentrations of amino acids and insulin in circulation that affect activities of two key translational regulators, eukaryotic initiation factor 2 (F2) and eukaryotic initiation factor 4E binding protein 1 (Bp). To construct a platform for prediction of global protein synthesis to nutritional stimuli, a dynamic, mechanistic model of translational control in whole tissues was developed.

Feeding aquaculture in an era of finite resources.

Aquaculture's pressure on forage fisheries remains hotly contested. This article reviews trends in fishmeal and fish oil use in industrial aquafeeds, showing reduced inclusion rates but greater total use associated with increased aquaculture production and demand for fish high in long-chain omega-3 oils. The ratio of wild fisheries inputs to farmed fish output has fallen to 0.

Effects of dietary fatty acid composition on the regulation of carnitine palmitoyltransferase (CPT) I in rainbow trout (Oncorhynchus mykiss).

Dietary fatty acid composition, particularly polyunsaturated fatty acids, can affect both genetic and non-genetic regulatory mechanisms of carnitine palmitoyltransferase (CPT) I, the main regulatory enzyme of mitochondrial fatty acid oxidation. We aimed to determine how these regulatory mechanisms were affected by changes in the fatty acid composition of the diet in fish. Specifically, we fed rainbow trout (Oncorhynchus mykiss) either a high polyunsaturated fatty acid (PUFA) diet, a high saturated fatty acid (SFA) diet or a mixed fatty acid control (CTL) diet for 8 weeks to determine if modifications of the dietary fatty acids would affect 1) the genetic expression of CPT I and its transcription factor peroxisome proliferator activated receptor (PPAR), 2) the mitochondrial membrane composition and if these modifications would affect CPT I sensitivity to malonyl-CoA, and 3) levels of malonyl-CoA in the tissues.

Determination of phosphorus fractions in animal protein ingredients.

Phosphorus (P) is present in different chemical compounds in animal feeds, and the solubility and digestibility of these different compounds are known to differ significantly. Animal protein ingredients generally have a high P content and are major contributors to total P of feeds for fish and other domestic animals. Estimation of different P compounds in these ingredients could help to improve the accuracy of estimates of digestible P contents of feeds.

Evidence that soyasaponin Bb retards disease progression in a murine model of polycystic kidney disease.

Background: We reported a lessened cyst growth in the pcy mouse model of polycystic kidney disease (PKD) when mice were fed a soy protein isolate (SPI)-based diet and hypothesized that the soyasaponins may be associated with this therapeutic effect. The effects of feeding a saponin-enriched alcohol extract (SEAE) from SPI, an isoflavone- and saponin-enriched soy supplement (Novasoy 400), or a 99.5% pure soyasaponin Bb powder on cyst growth are reported here.