Comparison of 3 different reinforcements of learning in dogs (Canis familiaris)

Effective dog training involves reinforcement of the dog's correct actions in response to specific cues given by the trainer. Food is usually selected as the primary reinforcer (reward), although this selection does not necessarily account for the learning preferences of individual dogs. We evaluated the relationship between reward and learning efficiency. Fifteen dogs were allocated to 3 different reward groups (food, stroking, and praise) and trained by an identical process. The food reward was the only one that shortened the time taken for the response to the command to be completed. However, this difference occurred only in the early training stages and not later in the training process.     

Morphological analysis on comparison of organic and chemical fertilizers on grain quality of rice at different planting densities

ABSTRACT

Effects of organic (Italian ryegrass and Bokashi) and chemical fertilizer on growth, yield, and grain quality of rice (Oryza sativa L.) were compared under different planting densities in 2013/2014 and 2014/2015. Italian ryegrass was incorporated into the soil as green manure. Bokashi (a mixture of organic materials) was applied as basal dressing. To measure yield and its components, 30 hills were chosen for each treatment. Rice grains were harvested from each treatment to assess the grain quality and to evaluate accumulation structures using a scanning electron microscope. Bokashi treatment increased panicle number per hill, ripened grain percentage, panicle number per m², and grain yield compared to no fertilizer treatment at normal planting density. Chemical fertilizer treatment increased plant length at high planting density. Italian ryegrass and Bokashi treatments promoted the taste point (taste score as reference) by reduction of amylose and protein contents at normal planting density in contrast to chemical fertilizer. 1000-grain weight, panicle number per m², and grain yield were higher at high planting density than at normal planting density. However, high planting density decreased panicle number per hill and spikelet number per panicle. It also enhanced the amylose content of rice grain. Scanning electron microscopic observation revealed that chemical fertilizer treatment marked up protein bodies and their traces on amyloplasts. However, Bokashi treatment produced large amyloplasts, which included many starch granules. These results show that Italian ryegrass and Bokashi can offset reductions of chemical fertilizer and can lead to sufficient starch accumulation structures in rice grains.     

Evaluation of the Subchronic Toxicity of Dietary Administered Equisetum arvense in F344 Rats

Equisetum arvense, commonly known as the field horsetail, has potential as a new functional food ingredient. However, little information is available on its side effects, and the general toxicity of Equisetum arvense has yet to be examined in detail. In the present study, we evaluated the influence of administration in diet at doses of 0, 0.3, 1 and 3% for 13 weeks in male and female F344 rats. No toxicity was detected with reference to clinical signs, body weight, urinalysis, hematology and serum biochemistry data and organ weights. Microscopic examination revealed no histopathological lesions associated with treatment. In conclusion, the no-observed-adverse-effect level (NOAEL) for Equisetum arvense was determined to be greater than 3% in both sexes of F344 rat (males and females: >1.79 g/kg BW/day and >1.85 g/kg BW/day, respectively) under the conditions of the present study.     

Protocol: a simple gel-free method for SNP genotyping using allele-specific primers in rice and other plant species

Background  

Genotype analysis using multiple single nucleotide polymorphisms (SNPs) is a useful but labor-intensive or high-cost procedure in plant research. Here we describe an alternative genotyping method that is suited to multi-sample or multi-locus SNP genotyping and does not require electrophoresis or specialized equipment.     

Perivertebral B-Cell Lymphoma in a Queensland Koala (Phascolarctos cinereus adustus) with Paralytic Symptoms in the Hind Limbs

A male Queensland koala (Phascolarctos cinereus adustus) at Kanazawa Zoological Gardens (Kanagawa, Japan) exhibited paralytic symptoms in the hind limbs. Computed tomography and magnetic resonance imaging revealed a mass on the left ventral side of the 11th to 13th thoracic vertebrae, and the presence of myelitis or edema in the spinal cord. The koala was under anesthesia during the examination and suddenly developed ventricular fibrillation and died. Necropsy revealed a firm flat ovoid hemorrhagic mass on the vertebrae. Following a microscopic examination including immunohistochemistry, the perivertebral mass was diagnosed as B cell lymphoma. Therefore, neoplastic cell infiltration into the spinal cord may cause paralytic symptoms in the hind limbs.     

Molecular mechanism of fertilization in the pig

At fertilization, the sperm triggers resumption from the arrest, extrusion of the second polar body and pronuclear formation, the events of which are collectively acknowledged as ‘oocyte activation’. In all species up to date, oocyte activation requires a fertilization‐associated increase in the intracellular concentration of calcium. Especially in mammals, the signal of intracellular calcium rise at fertilization consists of periodical rises, which are also referred to as calcium oscillations. Our recent results suggest that these calcium oscillations have an important role in not only oocyte activation but also development of mammals. Pigs are animals of great agricultural value and ones in which assisted reproductive techniques, including somatic cell nuclear transfer, to produce gene‐modified pigs. Although reconstructed embryos require artificial activation stimuli which mimic fertilization‐associated increase of intracellular calcium in the oocytes, it has been known that the developmental ability of the oocytes after artificial activation is low and the regimen seems to be required for improvement. Recently we focused on two molecules, phospholipase C zeta and inositol 1,4,5‐triphosphate receptor which have important roles in regulation of calcium oscillations during fertilization in mammals, including pigs. In this review, we will discuss the present status and future perspective of molecular mechanisms during fertilization in pigs.     

Influence of temperature and feeding regimes on growth and notochord deformity in reared <Emphasis Type="Italic">Anguilla japonica</Emphasis> leptocephali

The high mortality rate of reared Japanese eel Anguilla japonica larvae is largely due to lower growth rate and the higher rate of deformed larvae. To establish an effective rearing protocol for this species, we examined the effects of water temperature and feeding regimes on their growth and notochord kyphosis. Larvae at 165 days post hatching were reared for 28 days at mean temperatures of 24, 25 and 27 °C, and were fed 4 or 6 times per day. Larval growth rate was significantly higher in larvae reared at 24–25 °C and fed 6 times per day. However, growth rate was significantly reduced at 27 °C, suggesting a shortage of metabolic energy due to an elevated cost of the higher basal metabolic rate at higher temperatures and low nutritional performance of currently used artificial diet. Notochord kyphosis was promoted by elevated water temperature, and two-way ANOVA showed that water temperature and feeding frequency had combined effects on the deformity. These findings suggest the importance of concurrently manipulating both environmental and nutritional factors to produce healthy eel larvae in captivity.     

Cacao polyphenol extract suppresses transformation of an aryl hydrocarbon receptor in C57BL/6 mice

Dioxins enter the body through the diet and cause various toxicological effects through transformation of an aryl hydrocarbon receptor (AhR). Plant extracts and phytochemicals including flavonoids are reported to suppress this transformation. This paper investigates the suppression by a cacao polyphenol extract (CPE) of AhR transformation in vivo. The CPE was administered orally to C57BL/6 mice at 100 mg/kg of body weight, followed 1 h later by 3-methylcholanthrene (MC), an AhR agonist, injected intraperitoneally at 10 mg/kg of body weight. CPE suppressed the MC-induced transformation to the control level by inhibiting the formation of a heterodimer between AhR and an aryl hydrocarbon receptor nuclear translocator in the liver at 3 h postadministration. It also suppressed MC-induced cytochrome P4501A1 expression and NAD(P)H:quinone-oxidoreductase activity, whereas it increased glutathione S-transferase activity at 25 h. CPE constituents and their metabolites might contribute, at least in part, to the suppression of AhR transformation. The results indicate that the intake of CPE suppressed the toxicological effects of dioxins in the body.