Essential fatty acid requirement of the Chinese prawn, Penaeus chinensis

Effect of dietary linolenic acid/linoleic acid ratio on growth performance, hepatic fatty acid profiles and intermediary metabolism of juvenile yellow catfish Pelteobagrus fulvidraco

“…Poor WG and high FCR related to excess addition of LNA were also reported in other studies (Merican and Shim, 1997;Glencross et al, 2002;Smith et al, 2004). The interaction between dietary n−3 and n−6 FAs had considerable impact on the growth performance in yellow catfish, which supported the importance of the n−3 and n−6 FA balance in the diet (Yu and Sinnhuber, 1979;Xu et al, 1993Xu et al, , 1994Glencross et al, 2002). Such importance has been attributed to the effect of the FA balance on endogenous FA elongation and desaturation, in particular on competitive inhibition by LNA on LA for the Δ6 and Δ5 desaturase enzyme systems (Henderson and Tocher, 1987;Garg et al, 1988).…”

“…Under the n−3 to n−6 ratios of 1.48 to 2.45, dietary LA and LNA concentrations were approximately 1-1.1% and 1.3-2%, respectively. Similarly, Xu et al (1994) reported that the requirement level for LNA was between 0.7 and 1% in Penaeus chinensis. Kanazawa et al (1979) reported that the optimal dietary level of LNA for 9.90 ± 0.36c 9.40 ± 0.30b 8.83 ± 0.32a 8.47 ± 0.25a 8.47 ± 0.21a 8.57 ± 0.21a C20:2 1.03 ± 0.12b 0.93 ± 0.12ab 0.73 ± 0.06a 0.73 ± 0.06a 0.87 ± 0.31ab 0.83 ± 0.06ab C20:4 1.57 ± 0.35b 1.27 ± 0.21b 0.77 ± 0.12a 0.63 ± 0.06a 0.63 ± 0.06a 0.60 ± 0.10a n−6…”

“…Several researchers have examined interactive effects between EFAs by the addition of two or more EFAs to dietary lipid (Xu et al, 1993(Xu et al, , 1994Glencross and Smith, 1999), including the relationship between dietary n−3 and n−6 fatty acids (FAs). These studies indicated that the optimal ratio of dietary n−3 and n−6 FAs was very important to FA metabolism and lipid nutrition in aquatic species (Xu et al, 1993;Glencross et al, 2002).…”

Lipid composition and vitamin content of wild female Litopenaeus vannamei in different stages of sexual maturation

“…made on the FA requirements of Fen. chinensis juveniles Xu et al, 1993Xu et al, , 1994 The observed concentrations of vitamin C, a water-soluble component, in the ovaries Ž of immature, maturing and mature ovaries were high ranging from 351.6 to 461.2 mg y1 . kg .…”

“…recognized for many years Harrison, 1990 , and several studies with shrimp broodstock have noticed a good relationship with dietary n y 3 HUFA content and better egg and Ž . larval quality Xu et al, 1994;Cahu et al, 1995;Wouters et al, 1999 .…”