Intraspecific diversity of <Emphasis Type="Italic">Undaria pinnatifida</Emphasis> (Harvey) Suringar (Laminariales,Phaeophyta) from Japan,China and Korea,based on the <Emphasis Type="Italic">cox1</Emphasis> gene and ITS2 sequences

As a trial to develop a method of authenticating the place of origin of circulated Undaria pinnatifida products, we investigated their intraspecific genetic diversity using the mitochondrial cytochrome c oxidase subunit 1 gene (cox1) and the internal transcribed spacer 2 (ITS2) region of the nuclear ribosomal DNA (rDNA) sequence. Four dried U. pinnatifida products labeled with their origins (one from Japan, one from China and two from Korea), natural plants collected from three locations (two from Japan and one from China), and cultivated plants collected from two locations (one from Japan and one from China) were used in the present study. The amplified fragments of cox1 were 664 bp in length, and the aligned sequences were highly homologous. Among the nine sequences, no insertions or deletions were found and six substitution positions were detected, and they were classified into five haplotypes. In contrast, multiple highly variable regions were found in ITS2, and some of them carried a restriction site for Mbo II. Polymerase chain reaction-restriction fragment length polymorphism analysis showed different restricted profiles among the tested samples. The availability of molecular markers for authenticating food products of U. pinnatifida is discussed.     

Meat and bone meal replacement in diets for juvenile gibel carp (Carassius auratus gibelio): effects on growth performance, phosphorus and nitrogen loading

A 11‐week growth trial was conducted in a flow‐through system with juvenile gibel carp Carassius auratus gibelio to evaluate the effects of gradual replacement of fish meal (FM) by meat and bone meal (MBM) on growth performance, phosphorus (P) and nitrogen (N) loading. Six isonitrogenous (crude protein: 410 g kg^?1) and isoenergetic (gross energy: 18 kJ g^?1) diets were formulated. FM was used as the control protein. In the other five diets, 20, 40, 60, 80 and 100% FM protein was substituted with MBM₂₀, MBM₄₀, MBM₆₀, MBM₈₀, MBM₁₀₀, respectively. Total P content in the diets ranged from 16.0 to 28.3 g kg^?1 and the available P was 5.0–6.6 g kg^?1. The results showed that the best growth was achieved with fish fed on the control diet and MBM₂₀. Final body weight, weight gain, feed efficiency, protein retention efficiency and energy retention efficiency decreased with increased dietary MBM. No significant differences were found in the feeding rate and hepatosomatic index between the groups. Apparent digestibility coefficient (ADC) of dry matter, protein and P decreased with increase in dietary MBM, while there were no significant differences in the ADC of energy. P and N retention decreased linearly while P and N loading increased linearly with the increased dietary MBM levels. No significant differences were observed in the activity of alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase, as well as pyruvate kinase in liver or in serum. Total superoxide dismutase activity in MBM₂₀ was significantly higher than that of MBM₁₀₀.