Effects of different salinities on amino acid profile in Artemia franciscana

The effects of different salinity levels, including 10–15, 30–35, 70–75, 110–115 and 150–155 ppt, were evaluated on survival and the body amino acids (BAA) of Artemia franciscana. The results were expressed as total essential (TE), non‐essential (NE) and total amino acids (TAA); also, the ratio of the TE to NE (ENAA) on days 3 and 13 of the culture is reported. The study of changes in Artemia BAA showed that with the increase in the water salinity, the TE, NE and TAA increased significantly on days 3 and 13 of the culture. However, the highest ratio of ENAA was observed in the 110 gL^?1 salinity treatment on day 3 (1.067 ± 1.25). Regarding the effects of different salinity treatments on the survival rate of Artemia, it was observed that, generally, an increase in the water salinity would reduce the survival rate of this species. This reduction was observed on day 3 of culture in the salinity treatments above 120 (66.66 ± 1.68%) and below 30 gL^?1 (89.66 ± 0.34%) and on day 13 of culture in the salinity treatments below 30 (11.86 ± 0.13%) and above 70 gL^?1. Basically, it can be concluded that A. franciscana culture at a salinity of 110 gL^?1 can lead to the biological enrichment of Artemia in terms of amino acid profile.     

Factors that influence the level of weed seed predation: A review

Herbicides applied alone have failed to reduce weed populations in agricultural ecosystems. The use of this management strategy has followed other problems such as damage to ecosystems and organisms that live in it. Herbicide resistance in weeds has also occurred more quickly based on the application of herbicides. Today, most scientists are looking for new integrated weed management programs in agricultural ecosystems. Biological control is one of the most effective ways of weed management. In this way, living organisms are used to reduce and control weed species in arable lands. Weed seed predators, including predispersal and postdispersal predators as biological control agents, can be primary factors of weed seed mortality in agricultural ecosystems. This review has discussed factors influencing seed predator populations, activity, and granivory. Knowledge of the interrelations between factors and seed predators can contribute to designing future strategies that augment weed seed predator activity and enhance weed seed consumption as a component of an integrated weed management system.     

Nitrate nitrogen in the soil profile and drainage water as influenced by manure and mineral fertilizer application in a Barley–Carrot production system

Nitrate-N (NO₃ ^?-N) is a ubiquitous pollutant in both surface and groundwater in many agro-ecosystems. This has elicited a concerted effort to identify management strategies that mitigate NO₃ ^?–N pollution, without compromising crop yield. This study was conducted on a field site located at the Bio-Environmental Engineering Centre (BEEC) in Truro, NS, Canada during 1999 and 2000. The site has been used since 1997 to investigate the relative effect of inorganic versus organic fertilizer (liquid hog manure; LHM) applied at rates (70 kg N ha^?1) on NO₃ ^?-N leaching from a carrot rotation system. NO₃ ^?-N concentrations were monitored in both the soil profile and in tile drainage effluents from eight treatment plots. The LHM treatment elicited significantly (P < 0.01) higher soil NO₃ ^?-N concentrations than inorganic fertilizer (IF) in June and October during 1999, but not 2000. The sampling date and soil depth were significant in most cases. Annual flow weighted averages (FWA) of NO₃ ^?-N in drainage water were generally greater for plots receiving LHM (15.4 and 10.5 mg L^?1 for 1999 and 2000, respectively), when compared to IF (8.9 and 6.0 mg L^?1 for 1999 and 2000, respectively), but the difference was significant (P < 0.05) only in 1999. Maximum NO₃ ^?-N concentrations in drainage water were similar for both treatments, while the LHM treatment had a significantly higher percentage of samples that were > 10 mg L^?1. The total NO₃ ^?-N load was greater for the LHM treatment when compared to the IF treatment in 1999. Barley and carrot yields were unaffected by treatment applications.     

Effect of Sire-Associated Factors on Secondary Sex Ratio of Offspring in Equine

The objective of the present study was to evaluate the effect of breed of stallion and individual stallion on secondary sex ratio (SSR; the proportion of male foals at birth). Data associated with the sex of foals and the sire, as well as the breed and age of sire were retrieved from the database of the Equestrian Federation of the Islamic Republic of Iran. In total, data consisted of 4,491 birth records from 92 stallions. Stallions were from three breeds of Arabian, Thoroughbred, and Akhal-Teke. Data were analyzed using univariable and multivariable logistic regression. Proportion of colts was 63.0% (427/678), 46.1% (1,545/3,355), and 53.9% (247/458) in Arabian, Thoroughbred, and Akhal-Teke stallions, respectively. In Arabian stallions, SSR was skewed toward males (P < .0001; odds ratio, 1.701), whereas in Thoroughbred stallions, it was skewed toward females (P = .001; odds ratio, 0.853). Secondary sex ratio was not skewed in Akhal-Teke stallions (P > .05). Secondary sex ratio in Thoroughbred stallions was lower than that in Arabian (P < .0001; adjusted odds ratio, 1.983) and Akhal-Teke (P = .010; adjusted odds ratio, 1.527) stallions, but SSR did not differ between Arabian and Akhal-Teke stallions (P > .05). There was the effect of individual stallion on SSR in Arabian and Thoroughbred breeds (P < .0001) but not in Akhal-Teke breed (P > .05). In conclusion, the present study showed the effect of breed of stallion and stallion itself on sex ratio of foals.     

Low Concentration of Anti-Müllerian Hormone in Mares with Delayed Uterine Clearance

Luteal dysfunction has been observed in mares with defective uterine clearance. Association of low ovarian reserve with luteal dysfunction and abnormal endometrial thickness has been reported in bovine. Anti-Müllerian hormone (AMH) has been indicated as a marker for ovarian reserve in bovine and originates primarily from the ovary in equine. The present study evaluated serum AMH concentration in mares with delayed uterine clearance versus that in mares without delayed uterine clearance. Of 49 mares assigned to the study, 12 and 37 mares were diagnosed with and without delayed uterine clearance, respectively. Delayed uterine clearance was determined based on history and the observation of intrauterine fluid in ultrasonographic examination 24 hours after natural breeding. Serum AMH concentration was measured during estrus. Concentration of AMH was lower in mares with delayed uterine clearance (0.4 ± 0.1 ng/mL) than in those without delayed uterine clearance (1.1 ± 0.1 ng/mL). In conclusion, the present study indicated possible associations between ovary-lined mechanisms and uterine clearance failure in mares.     

Wood anatomical changes due to uptake of cadmium and lead from contaminated soils in Acer velutinum seedlings

We investigated wood anatomical changes due to uptake and accumulation of cadmium and lead from contaminated soils in Acer velutinum Boiss seedlings. Two-year old seedlings were exposed for 180 days to soil concentrations with varying cadmium and lead concentrations. We measured three wood anatomical traits, average vessel area(μm2), vessel number per square millimetre, and vessel lumen area percentage (%). For assessing the cadmium and lead accumulation, we measured the concentrations in the soil, leaf, stem, and root. Average vessel area and vessel lumen area percentage were similar (p>0.05) incontrol and treated seedlings. Vessel number per square millimetre showed a decreasing trend from pith to bark in control and treated seedlings, and the trend was more pronounced in treated seedlings. We conclude that vessel number per square millimetre in A. velutinum is influenced by soil contamination. A. velutinum Boiss is not a suitable species for remediation of soils contaminated by cadmium and lead but it can beused as an indicator of the soil lead contamination, because lead concentrations in seedlings increased with increasing amount of lead in the soil.     

Improvement of reproductive indices,lysozyme activity,and disease resistance in live‐bearing ornamental fish,Poecilia latipinna using Artemia supplementation with treated yeast cell,Saccharomyces cerevisiae

In the present study, the effects of Artemia supplemented with 2‐β‐mercapto‐ethanol (β‐ME) treated yeast cell, Saccharomyces cerevisiae, on growth and reproductive performance, lysozyme activity, and disease resistance to Aeromonas hydrophila of freshwater ornamental species, Poecilia latipinna, were investigated. Within 60 days, molly fish were fed with three treatments including commercial food (T1), un‐supplemented Artemia (T2), and Artemia supplemented with β‐ME‐treated yeast cell (at concentration of 4 × 10⁷ CFU/L of water) (T3). After the feeding period, the fish were exposed to 100 μl of a suspension (1.1 × 10⁷ cells/ml) of A. hydrophila (BCCM5/LMG3279) and the cumulative mortality rates were recorded for 12 days. No significant difference was found between survival rate and growth performance of P. latipinna except for weight gain that was higher in fish fed through Artemia supplemented with β‐ME‐treated yeast cell compared to control group. Fecundity rate was significantly improved in fish fed using T3 with the maximum amount of 49.5 ± 2.29 per female (p < 0.05). Besides, lysozyme activity was significantly increased in group 3 (p < 0.05). Moreover, lowest fish mortality was significantly observed in this treatment (p < 0.05). In addition, the number of colonies formed by yeast cell in T3 (634 × 10³ CFU/g intestine) showed significant difference with other treatments (p < 0.05). In sum, Artemia enriched with β‐ME‐treated yeast improved reproductive indices, immune responses, and resistance against A. hydrophila of P. latipinna.     

Growth and survival of winter flounder (Pseudopleuronectes americanus) larvae reared on different photoperiod regimes from hatch to metamorphosis

The aim of this study was to determine the effect of photoperiod on growth and survival of winter flounder, Pseudopleuronectes americanus, from hatch until metamorphosis. Sixteen 100 L upwelling tanks were stocked with larvae at an initial stocking density of 20 larvae/L. Larvae in eight tanks were provided with continuous light (24 hr light/0 hr dark), while those in the remaining eight tanks were grown under a photoperiod of 14 hr light/10 hr dark. Tanks were sampled for larval standard lengh from 6 to 28 days post‐hatch, and the number of live larvae, live metamorphosed and dead metamorphosed fish were recorded at the termination of the experiment (starting 46 dph). Results indicated that larvae provided with continuous light were larger than those sampled from 14 hr light/10 hr dark treatment. No effect of photoperiod on the number of non‐metamorphosed fish recovered at the end of the experiment was detected. On the contrary, over three times as many fish survived and reached metamorphosis under continuous light. An ANCOVA model showed a significant interaction between light and age. Both regressions were significant and provided the following growth equations: SL_{24 hr light/0 hr dark} = 0.101 × age + 2.55 (r² = 0.96) and SL_{14 hr light/10 hr dark} = 0.094 × age +2.45 (r² = 0.97). Using 6.36 ± 0.059 mm SL as the mean size at metamorphosis, larvae experiencing continuous and 14 hr light/10 hr dark photoperiods would reach metamorphosis in 38 and 42 days respectively.     

Comparison of intranasal and intramuscular ketamine‐midazolam combination in cats

ObjectiveThe aim of the present study was to compare intranasal (INS) and intramuscular (IM) routes of administration of a ketamine-midazolam combination in cats.Study designRandomized block design.AnimalsTwelve healthy mixed breed cats (six males and six females).MethodsThe drug combination was ketamine (14 mg kg⁻¹) and midazolam (0.5 mg kg⁻¹). In the IM group, drugs were injected into quadratus femoris muscle; in the INS. group, the combination dropped equally into the two nostrils. Pulse and respiratory rates, peripheral haemoglobin oxygen saturation (SpO₂) and rectal temperature were monitored before and at intervals after drug administration. Time to onset and duration of sedation and, during recovery to head up, sternal recumbency and recovery were recorded.ResultsThere were no significant differences between the groups in any time measured except for recovery to sternal recumbency, where time was lower in the INS than in the IM (p = 0.034). Respiratory rate was greater in the INS than in the IM group (p = 0.029), but there was no difference between groups in other physiological parameters. In both groups SpO₂ was low before and fell further during sedation.ConclusionsThe results substantiated that INS ketamine-midazolam can produce effective sedation in cats.Clinical relevanceIntranasal (INS) administration of ketamine-midazolam is atraumatic, and its use may avoid the pain of injection of ketamine combinations when this drug is used to induce sedation in cats.