SEM studies on acanthocephalan parasite, Echinorhynchus veli infecting the fish Synaptura orientalis (Bl & Sch, 1801).

Echinorhynchus veli (George and Nadakal, 1978), an acanthocephalid worm infesting the estuarine flat fish, Synaptura orientalis, was collected from the Veli lake, Kerala. The parasite was recovered from the intestine of the host fish. The detailed surface morphology was studied with the help of scanning electron microscope. The study revealed a cylindrical, medially swollen proboscis with a flat apex, backward directed hooks, each with smooth surface, broad base, pointed tip and an epidermal elevation at the point of insertion. A pair of sensory pits was seen at the base of the proboscis. The neck was well developed with densely packed epidermal micropores. Paired sensory pits were seen at the base of the neck and a collar between it and the trunk. The epidermis of the trunk has microtriches and micropores. The female genital pore was circular, and terminal in an elevated orifice. In male, the copulatory bursa was directed ventrally, with well-defined rim and several sensory papillae.

Modification of aftertaste with a menthol mouthwash reduces food wanting, liking, and ad libitum intake of potato crisps.

This research investigated the effect of modifying the aftertaste of potato crisps on (1) temporal sensory perception and (2) appetite using three mouthwash conditions (no mouthwash, a water mouthwash, and a menthol mouthwash). For the sensory study, 17 screened female subjects were trained on the Temporal Dominance of Sensations (TDS) methodology. Subjects undertook TDS to monitor all sensory attributes during the mastication of a 2 g crisp until swallowing (at 20s), then conducted the mouthwash, and then continued the TDS task to monitor aftertaste until 90s. For the appetite study, 36 subjects (18 male, 18 female) completed 100 mm Visual Analogue Scales (VAS) for desire, liking, hunger, and thirst, followed by an ad libitum eating task. For the VAS scales testing, subjects chewed and swallowed a 2 g crisp, and then immediately conducted the mouthwash before completing the VAS scales. For the ad libitum task, subjects were given 12 min to consume as many crisps as they desired on a plate (up to 50 g). Every three minutes they were required to conduct a mouthwash. TDS results showed that in comparison with no mouthwash, the water mouthwash significantly reduced aftertaste attributes such as savoury, salty, and fatty mouthcoating, and the menthol mouthwash significantly increased aftertaste attributes of cooling, minty, and tingly. The water mouthwash did not influence desire and liking of crisps, or hunger and thirst. The water mouthwash did not influence ad libitum intake of the crisps over a 12 min period. The menthol mouthwash significantly reduced desire and liking of the crisps, as well as hunger and thirst. Furthermore, the menthol mouthwash significantly reduced ad libitum crisp intake by 29% over the 12 min period.

The role of oral processing in dynamic sensory perception.

Food oral processing is not only important for the ingestion and digestion of food, but also plays an important role in the perception of texture and flavor. This overall sensory perception is dynamic and occurs during all stages of oral processing. However, the relationships between oral operations and sensory perception are not yet fully understood. This article reviews recent progress and research findings on oral food processing, with a focus on the dynamic character of sensory perception of solid foods. The reviewed studies are discussed in terms of both physiology and food properties, and cover first bite, mastication, and swallowing. Little is known about the dynamics of texture and flavor perception during mastication and the importance on overall perception. Novel approaches use time intensity and temporal dominance techniques, and these will be valuable tools for future research on the dynamics of texture and flavor perception.

Dinurus ivanosi sp. nov. (Digenea: Hemiuridae) from the stomach of dolphin fish, Coryphaena hippurus, caught off the Kerala Coast, India.

A new species of stomach fluke, Dinurus ivanosi (sp. nov.), was recovered from the dolphin fish, Coryphaena hippurus, off the Kerala Coast, India. It is similar to other Dinurus species in the plicated prosoma, trilobed seminal vesicle and seven vitellaria, but differs from them in the length of the pharynx, unequal lobes of the seminal vesicle and unequal size of the testes. The most important diagnostic features of the new species are the general shape and proportions of the body, the position of the oral sucker, elongated pharynx, small distal lobe of the seminal vesicle, and larger anterior testis, smaller egg size, short and slender vitellaria and the limited extent of the vitelline field.

Synthetic DNA-based genetic markers reveal intra- and inter-species DNA sequence variability in the Bubalus bubalis and related genomes.

A series of synthetic oligonucleotide probes were developed as markers for genetic analysis and molecular systematics of Bubalus bubalis and other eutherian mammals. A very high level of heterozygosity (approximately 95%) was observed in the bubaline genome, with an overall band-sharing probability of 2.08 x 10(-11) using (TGG)6 and Hinf I probe-enzyme combination. Breed affiliation studies on different buffalo breeds, viz. Toda, Surti, Mehsana, and Murrah, revealed that the semiwild Toda breed belonged to a distinct group. The desired genotypes in each successive generation in an actual breeding program were also identified by employing a DNA fingerprinting approach using these markers. Estimation of genetic distances by calculating the mean allelic frequencies at (CA)n, (TGG)n, and (GGAT)n repeat loci between buffalo and other related animals such as horse (order Perisodactyla), rabbits (order Lagomorpha, (pigs, cattle, goat, and sheep (order Artiodactyla) revealed that with respect to the genetic distance coefficient (GDC), goat (caprine) was closer to buffalo (GDC = 0.0005) than sheep (ovine) (GDC = 0.0007). The genetic distance between horse and buffalo was calculated to be 0.4085, indicating that compared to other animals, horse was distantly related to buffalo. The understanding of overall allelic variations and breed affiliation of the bubaline genome will contribute to the propagation and conservation of the desired germ plasm and better management of this species.

Analysis of VNTR loci in fish genomes using synthetic oligodeoxyribonucleotide probes.

A set of synthetic oligodeoxyribonucleotide (oligo) probes, OAT18, OMS1 and OAT24 carrying the (TGG)6, (GGAT)4 and (GACA)6 repeat motifs, respectively, was used to analyze the variable number tandem repeat (VNTR) loci in the genomes of Oncorhyncus mykiss (rainbow trout; family Salmonidae), Oreochromis mossambicus and Oreochromis niloticus (both tilapia belonging to family Cichlidae). Of all the oligos and enzymes (AluI, MboI, HaeIII and HinfI) used, the OAT18/HaeIII combination was found to be most informative for detecting DNA fingerprinting in rainbow trout, while the OMS1/MboI combination gave the most informative pattern for the Or. niloticus genome. In the rainbow trout genome, all three repeat loci were hypervariable, revealing varying degrees of polymorphism as compared to tilapia genomes. Startlingly, the OAT24 probe did not cross-hybridize with Or. mossambicus and lamprey salmon (Lampertra japonica) although GACA repeats have been reported to be evolutionarily conserved in all eukaryotes studied thus far. Cluster analysis with respect to GGAT repeat loci revealed that Or. niloticus diverged from Or. mossambicus before the separation of On. mykiss, suggesting the relatively recent evolution of these loci in rainbow trout, compared to the tilapia genomes. These highly informative probes will find application in various genetic studies of fishes.