the potential of marine actinobacteria particularly streptomyces as a single cell protein (scp) feed for the growth of ornamental fish, xiphophorus helleri has been investigated. the streptomyces strains used as scp were isolated from the marine sponges, namely callyspongia diffusa , mycale mytilorum , tedania anhelans and dysidea fragilis . six scp feeds were prepared and their effects were co...

This work investigated the relationship between water characteristics and infestation of protozoan parasites, Icthyophthirius multifiliis and Trichodina sp., in swordtails (Xiphophorus helleri) and platy (Xiphophorus maculates) collected in an ornamental fish farm in São Paulo, Brazil. Fish were monthly collected from ponds and tanks for one year. The prevalence rates in fish from tanks and pon...

The effects of dietary supplementation of commercial human probiotic, Lactobacil and antibiotic, oxytetracycline on the growth, survival, disease resistance and content of intestinal microflora in two ornamental fishes, viz., goldfish, Carassius auratus and swordtail, Xiphophorus helleri were studied. The total wet weight gain, food conversion ratio and specific growth rate of C. auratus did no...

The potential of Streptomyces as a probiotic feed for the growth of ornamental fish Xiphophorus helleri has been investigated. The Streptomyces strains used as probiotics were isolated from the marine sponges, namely Callyspongia diffusa, Mycale mytilorum, Tedania anhelans and Dysidea fragilis. Seven probiotic feeds were prepared and their effects were compared with those of control diet contai...

Fish that are colored in nature often acquire faded coloration under intensive culture conditions. Experiments adding top-coated algae to the diets of ornamental fish have resulted in color enhancement. Freshwater red velvet swordtails Xiphophorus helleri, rainbowfish Pseudomugil furcatus, and topaz cichlids Cichlasoma myrnae became significantly more intensely colored when fed a diet containin...

To determine the nutritional requirment for iron in fish growth, the effect of daily addition of supplemental ferrous sulfate on the growth of Xiphophorus helleri and Xiphophorus maculatus (the swordtail and the platyfish) was measured by determination of weight gain and hematocrit levels. Both variables increased as a result of the added iron. The effectiveness of the treatment diminished as s...

Six commonly freshwater ornamental fish, namely Poecilia rediculata (guppy); Poecilia sphenops (black molly); Cichlosoma sp. (Cichlidae); Xiphophorus maculatus (platy); Carassius auratus (goldfish) and Symphisodon discus (discus) were examined for parasites during a four years study (19982002) in Turkey. The parasites species found included: Ichthyobodo sp., Ichthyophthirius multifiliis, Chilod...

The expression of the c-src gene in embryonic and adult tissue of the teleost fish Xiphophorus helleri was analyzed by in-situ hybridization. The highly conserved fish c-src gene was found to be expressed at high levels in midterm embryos, where c-src mRNA was localized in developing neurons of the sensory layer of the differentiating retina and in the developing brain. In adult tissues the exp...

Fish of the genus Xiphophorus are polymorphic for black pigmentation patterns. Certain intra- or interspecific hybrids exhibit enhanced expression of these patterns, leading in many cases to malignant melanoma. Because no recombination was ever observed between the pattern information and the genetic predisposition to develop melanoma after hybridization, a "tumor gene" (Tu) was postulated that...