Menthol and 1,8‐cineole as new anaesthetics in common carp,Cyprinus carpio (Linnaeus, 1758)

This study describes anaesthetic efficacy of menthol and 1,8‐cineole in common carp, Cyprinus carpio, in comparison with eugenol. Common carp fingerlings were exposed to eugenol: 5, 10, 15, 25, 35, 50, 75, 100, 150 and 200 ppm; menthol: 5, 10, 15, 25, 50, 100, 200, 300, 400, 500 and 600 ppm; 1,8‐cineole: 100, 150, 200, 300, 400, 500, 600, 700 and 800 ppm. Induction time and recovery time were recorded. Results showed that menthol and 1,8‐cineole anesthetized the fish at higher concentrations compared to eugenol. The fish exposed to menthol showed common fish behavioural responses to anaesthesia, similar to eugenol. But, 1,8‐cineole‐exposed fish showed tail‐up swimming, which was not observed before. Also, 1,8‐cineole failed to completely cease muscle tone. Exposure to 200 ppm eugenol and 600 ppm menthol resulted in 40% and 20% mortality, respectively. Induction time was exponentially dependent on anesthetic concentrations. Recovery time was linearly correlated to eugenol and menthol, but not 1,8‐cineole concentrations. Recovery time was exponentially dependent on induction time in the fish anesthetized with eugenol and menthol, but not 1,8‐cineole. Menthol and 1,8‐cineole are recommended for carp anaesthesia. Menthol is capable to anesthetize common carp within 1–3 min at 118–512 ppm. Common carp anesthetized with 108–133 ppm menthol recovers within 5 min. 1,8‐cineole failed to anesthetize common carp within less than 150 s at 300–800 ppm concentrations. However, it anesthetizes carp within 3 min at 595 ppm concentration. Also, 1,8‐cineole is not recommended for fish surgery. Both menthol and 1,8‐cineole were less efficacious than eugenol.     

Effects of foliar spray of nano-particles of FeSO4 on the growth and ion content of sunflower under saline condition

This study investigated the effects of foliar spray of normal and nano-particles of iron sulfate (FeSO₄) on the response of sunflower cultivars to salinity. Treatments included five cultivars (Alstar, Olsion, Yourflor, Hysun36 and Hysun33), two salinity levels (0 and 100 mM sodium chloride (NaCl)), and three levels of fertilizer application. Fertilizer treatments were the foliar application of normal and nano-particles of FeSO₄. Foliar application of FeSO₄ in either form increased leaf area, shoot dry weight, net carbon dioxide (CO₂) assimilation rate (A), sub-stomatal CO₂ concentration (Ci), chlorophyll content, Fv/Fm and iron (Fe) content and decreased sodium (Na) content in leaves. The extent of increase in chlorophyll a content by foliar spray of FeSO₄ nano-particles was significantly greater than normal form. The results showed that the FeSO₄ nano-particles increased biomass production of sunflower plants greater in comparison with normal form, although no significant difference was found between two forms.     

Anaesthetic efficacy and biochemical effects of 1,8‐cineole in rainbow trout (Oncorhynchus mykiss,Walbaum, 1792)

The aim of the present study was to investigate the anaesthetic efficacy and biochemical effects of 1,8‐cineole (cineole) in rainbow trout (Oncorhynchus mykiss). The fish were exposed to 200, 300, 400, 500, 600 and 800 μl/L cineole and time of induction of anaesthesia and recovery from anaesthesia were recorded. Thereafter, the fish haematological and biochemical responses to anaesthesia with different concentrations of cineole were studies. Moreover, the haematological and biochemical response of fish anaesthetized for 300 s with either cineole (283 μl/L) or eugenol (25 μl/L) were compared. Cineole at the concentrations of 200–800 μl/L induced stages 2, 3 and 4 anaesthesia within 109‐29.3, 226‐59 and 418‐117 s respectively. Increase in anaesthesia induction time led to higher stress responses and enzymes’ activity characterized by elevation in red blood cell (RBC), white blood cell (WBC), blood haematocrit and haemoglobin, and plasma cortisol, glucose and lactate levels, and aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase and creatine phosphokinase (CPK) activities. However, cineole concentrations had no significant effects on plasma alanine aminotransferase (ALT) activity and ions levels. Comparison of cineole with eugenol showed that cineole showed less change in blood RBC and plasma AST, ALP, CPK, cortisol and glucose levels compared to eugenol. In conclusion, cineole is efficient to anaesthetize trout at concentrations of 200–800 μl/L. Increase in cineole concentration shortens anaesthesia induction time, stress response and probably tissue damage. The concentrations of 600–800 μl/L cineol is recommended for rapid sampling as it causes the least stress and enzymatic responses. The present results suggest that cineole causes slightly lower side effects in trout compared to eugenol.     

Enriched Artemia with L-lysine and DL-methionine on growth performance,stress resistance,and fatty acid profile of Litopenaeus vannamei postlarvae

A 15-day study was conducted to evaluate the effect of enrichment of Artemia metanauplii with four different emulsions, including: (A) Easy-DHA Selco; (B) Easy-DHA Selco + L-lysine (4 g/L); (C) Easy-DHA Selco + DL-methionine (4 g/L); and (D) Easy-DHA Selco + L-lysine (2 g/L) + DL-methionine (2 g/L) on growth and stress resistance of white leg shrimp Litopenaeus vannamei larvae (from Mysis I to postlarvae12). It is noticed that shrimp PL in group B had the highest wet (36.1 ± 3.1 mg) and dry (1116.7 ± 60.0 µg) weights as well as stress resistance to fresh water (64.0 ± 5.5%).     

Anaemia and plasma lipid profile in common carp (Cyprinus carpio) exposed to ambient copper sulphate and nano‐scale copper oxide

The objective of this study was to determine the effects of copper sulphate (CS) and copper oxide nanoparticles (NCuO) on haematological characteristics and plasma lipid profile in Cyprinus carpio. Fish were exposed to CS (0.25 mg L^?1 Cu) and NCuO [0.25 (LNP) and 25 mg L^?1 (HNP) Cu] for 14 days. CS and LNP treatments showed hypochromic anaemia after 3 and 7 days, and macrocytosis and haemolytic anaemia after 14 days. HNP treatment showed hypochromic anaemia and polycythemia after 3 days, and macrocytosis and hypochromic anaemia after 7 days and haemolytic hypochromic anaemia after 14 days. All copper‐exposed fish showed leukopenia at all times, except for HNP after 7 days and CS after 3 days. CS treatment at all times, and NCuO treatments after 14 days showed elevated plasma bilirubin. CS (3rd and 7th days) and HNP (3rd day) treatments had significantly higher plasma triglyceride compared to the control. Significant increases in plasma cholesterol and lipoprotein levels were observed after 3 and 14 days in CS, and after 14 days in LNP treatment; whereas HNP treatment had significantly higher high density lipoprotein (HDL) and very low‐density lipoprotein (VLDL) levels after 3 days, and cholesterol, HDL and low‐density lipoprotein (LDL) after 14 days. In conclusion, CS and NCuO induce anaemia probably due to iron metabolism disorder and RBC destruction in carp. CS and NCuO (at high concentration) alter plasma lipid profile, which may be due to stress‐induced lipolysis and hepatobiliary damages. At similar concentrations, copper nanoparticles are less toxic to carp than copper ions.     

Serum biochemical and non-specific immune responses of rainbow trout (<Emphasis Type="Italic">Oncorhynchus mykiss</Emphasis>) to dietary nucleotide and chronic stress

The aim of the present study was to investigate whether supplementary nucleotide “Optimun” mitigates the adverse effects of chronic overcrowding in Oncorhynchus mykiss. Two experimental diets [control and nucleotide-supplemented (0.2 %)] and two rearing densities (10 and 30 kg m^?3) were combined to have four experimental treatments. The fish were reared for 45 days under different densities using different diets. At the end of the trial, FCR of the fish in higher density was significantly higher than those of the lower density. Nucleotide had no significant effects on growth performance and survival rate. Supplemented nucleotide significantly increased blood hematocrit, whereas it decreased serum total protein, total immunoglobulin (Ig) and creatinine. Overcrowding significantly increased serum glucose and total protein level and decreased serum lysozyme activity, but supplemented nucleotide produced no improvement in these items. No significant effect of overcrowding and dietary nucleotide was observed on serum cortisol. Supplemented nucleotide significantly increased serum urea under low stocking density. Overall, the results showed that 0.2 % “Optimun” had no positive effects on rainbow trout and also caused some immunological and metabolic problems. These findings are not in accordance with those obtained in the same species, with same nucleotide source and level, but acute stress; thus, further studies are encouraged on this topic.     

The role of glutamatergic and GABAergic systems on serotonin- induced feeding behavior in chicken

It has been reported that serotonin can modulate glutamate and GABA release in central nervous system (CNS). The present study was designed to examine the role of glutamatergic and GABAergic systems on serotonin- induced feeding behavior in chickens. In Experiment 1 intracerebroventricular (ICV) injection of MK- 801(NMDA receptor antagonist, 15 nmol) performed followed by serotonin (10 μg). In experiments 2, 3, 4, 5, 6 and 7 prior to serotonin injection, chickens received CNQX (AMPA/kainate receptor antagonist, 390 nmol), AIDA (mGluR1 antagonist, 2 nmol), LY341495 (mGluR2 antagonist, 150 nmol), UBP1112 (mGluR3 antagonist, 2 nmol), picrotoxin (GABA A receptor antagonist, 0.5 μg), CGP54626 (GABAB receptor antagonist, 20 ng) respectively. Cumulative food intake was determined at 3 h post injection. The results of this study showed that the hypophagic effect of serotonin was significantly attenuated by pretreatment with MK- 801 and CNQX (p?<?0.05) but AIDA, LY341495 and UBP1112 had no effect (p?>?0.05). Also, the inhibitory effect of serotonin on food intake was amplified by picrotoxin (p?<?0.05) while CGP54626 had no effect (p?>?0.05). These results suggest that serotonin as a modulator probably interacts with glutamatergic (via NMDA and AMPA/Kainate receptors) and GABAergic (via GABAA receptor) systems on feeding behavior in chicken.     

Intracerebroventricular injection of ghrelin produces hypophagia through central serotonergic mechanisms in chicken

It has been stated that central injection of ghrelin is acting as an anorexigenic peptide in chicken. Ghrelin activity was studied through some neuronal pathways. The present study was designed in 4 experiments to examine the hypophagic response of ghrelin through the central serotonergic system in chicken. The guide cannula was surgically implanted in the right lateral ventricle of the chickens. In experiment 1, intacerebroventricular injection with PCPA (1.5 mg) performed followed by ghrelin (0.6 nmol). In experiments 2, 3 and 4 prior to ghrelin injection, chickens received fluoxetine (10 μg), 8-OH-DPAT (15.25 nmol), SB242084 (1.5 μg) respectively via guide cannula intacerebroventricularly. Cumulative food intake was determined at 3 h post injection. The results of this study showed that flouxetine pretreatment significantly amplified ghrelin hypophagia in chicken (p?<?0.05). The hypophagic effect of ghrelin was attenuated by pretreatment with PCPA and SB242084 (p?<?0.05) but 8-OH-DPAT had no effect. These results suggest that hypophagic effect of ghrelin probably is mediated by serotonergic mechanisms via 5-HT_2C receptor.     

Effects of neonatal diarrhea and other conditions on subsequent productive and reproductive performance of heifer calves

Diarrhea is one of the most frequent diseases of neonatal calves in dairy herds. The aim of this study was to evaluate the effects of neonatal diarrhea and other conditions on subsequent first lactation milk production and reproductive performance of heifer calves up to the first calving. Seven hundred heifer calves (350 with and 350 without the history of diarrhea in first month of life) were monitored from birth until a year after calving. For each heifer, birth season, birth weight, ease of birth and occurrence of diseases from birth to the end of first lactation were recorded as independent variables. Interval from birth to first service, interval from birth to conception, interval from birth to first calving and 305-days milk yield in the first lactation were recorded as dependent variables. Effects of explanatory variables on productive and reproductive indices were evaluated by survival analysis and general linear model. Heifers with the history of diarrhea during the first month of their lives showed lower daily hazard of conception [Hazard ratio: 0.85 (95%CI: 0.73–0.99)] and calving [Hazard ratio: 0.84 (95%CI: 0.72–0.98)] than those of healthy heifers. Subsequent reproductive performance of heifer calves was also associated with birth season and ease of birth. Further, heifer calves born with birth weight of below 35 kg produced an average of 518 and 506 l less milk in their first lactation compared to calves with a birth weight 40–45 (p = 0.013) and greater than 45 kg (P = 0.033), respectively. These findings showed that occurrence of neonatal diarrhea and other neonatal parameters are associated with harmful effects on subsequent production and reproductive performance.