Effects of some dietary crude plant extracts on the growth and gonadal maturity of Nile tilapia (Oreochromis niloticus) and their resistance to Streptococcus agalactiae infection

Abstract

A 90-day feeding trial was conducted on the growth performance, feeding efficacy, body indices, various hematological and plasma biochemical parameters, and histopathological examination of the gonads from male and female Nile tilapia fingerlings when fed different crude plant extracts from Cinnamomum camphora, Euphorbia hirta, Azadirachta indica, or Carica papaya at 2 g kg(-1) compared to a control diet. This was followed by a 14-day challenge to Streptococcus agalactiae. All treatments were triplicated, and each treatment consisted of 30 fish. Results showed that C. papaya extracts were the most effective at delaying gonadal maturation to both male and female tilapia, as well as significantly increasing (P < 0.05) growth performance compared to the control treatment. Similarly, dietary C. camphora and E. hirta extracts also significantly improved growth, while no significant growth effect was detected between the A. indica and control treatments (P > 0.05). Further, crude body lipid was lower in the C. camphora, E. hirta and C. papaya treatments, but was only significantly lower for the E. hirta treatment compared to the control. Meanwhile, none of the hematological or biochemical parameters were significantly affected, although plasma ALT was significantly lower for tilapia fed A. indica compared to the control. After the 14-day bacterial challenge, tilapia fed C. camphora supplementation had significantly higher survival, compared to the control, but was not significantly higher than the other supplemented diets. Results indicate that dietary C. papaya extract can significantly promote growth and delay gonadal maturation to both male and female tilapia, while C. camphora was the most effective prophylactic to S. agalactiae and may be a cost-effective and eco-friendly alternative to antibiotics.

Effect of Garcinia kola seeds supplemented diet on growth performance and gonadal development of Oreochromis niloticus juveniles breed in ponds

“…Tropical forests contain many tree species that have supplied edible fruits for centuries. It has been previously reported in many research works that different plant additives can enhance growth in some fish species such as Oreochromis niloticus (Kareem et al 2016, Hassan et al 2018. Results from the present study indicate that there was an increase in the growth of the fish fed with different rate of dietary supplementation with G. kola seed.…”

Effect of dietary Aloe vera polysaccharides supplementation on growth performance, feed utilization, hemato-biochemical parameters, and survival at low pH in African catfish (Clarias gariepinus) fingerlings

“…The wider variety of medicinal herbs may justify their broad-spectrum medicinal properties that may act against a wide range of pathogens (Harikrishnan et al 2011). Crude extracts from Camellia sinensis (Abdel-Tawwab et al 2010), Carum carvi (Ahmad and Abdel-Tawwab 2011), Cinnamomum camphora, Euphorbia hirta, Azadirachta indica, and Carica papaya (Kareem et al 2016), Cynodon dactylon, Aegle marmelos, Withania somnifera, and Zingiber officinale extracts (Immanuel et al 2009) improved growth performances of Oreochromis niloticus juveniles when they were administered through diets, respectively. Similar findings were reported for Clarias gariepinus when their diet was dietary supplemented with Allium sativum peels (Thanikachalam et al 2010) and or Agaricus bisporus (Harikrishnan et al 2018), respectively.…”

Gonad maturation and spawning of cobia, Rachycentron canadum (Linnaeus, 1766) off the Dungun coast, Malaysia

“…Use of the gonadosomatic index (GSI) as an indicator of the reproductive condition of fish is well known and can be easily conducted with a high amount of samples (Zeyl, Love, & Higgs, ). Histological analysis is known to be a more accurate tool to ascertain the reproductive status of animals (Kareem, Abdelhadi, Christianus, Karim, & Romano, ), but is often cost and time prohibitive on the same scale as GSI measurements. Nevertheless, histology can be particularly useful when determining whether fish are synchronous or asynchronous spawners.…”

“…Histological analysis is known to be a more accurate tool to ascertain the reproductive status of animals (Kareem, Abdelhadi, Christianus, Karim, & Romano, 2016), but is often cost and time prohibitive on the same scale as GSI measurements. Nevertheless, histology can be particularly useful when determining whether fish are synchronous or asynchronous spawners.…”