The use of sugar beet pulp in pig diet to control skatole analysed by HPLC quantification method

This study aimed to determine the efficacy of a finishing diet added with sugar beet pulp to reduce backfat skatole of entire male pigs, using the optimised high-performance liquid chromatographic (HPLC) method. The study comprised 72 males Pietrain (Large White × Landrace), divided into two groups of 36 animals each. Pigs in group A (treatment) were fed a supplemented formula (addition of 10 % beet pulp). while animals in group B (control) received a commercial feed, both for a period of 14 days before slaughter. The isocratic HPLC method achieved the chromatographic separation of indolic compounds in approximately 3 min. Skatole was significantly lower ( p = 0.002) in group A, showing that beet root supplementation reduced skatole levels in pig fat. In addition, the optimised HPLC method was reliable, less time-consuming, and showed a resolution suitable for small amounts of skatole.(AU)

Is a short concentrate-finishing period in lambs raised on alfalfa pasture effective at reducing fat indoles contents and lightening meat colour?

Pasture-feeding in lambs has been associated with dark-coloured meat and high meat contents of volatile indoles (skatole and indole), which may be responsible for sensory defects. The risk of off-flavours is even higher when lambs graze alfalfa, because it is particularly rich in rapidly degradable proteins. Here, we investigated whether a short concentrate stall-finishing period in lambs that previously grazed alfalfa influences meat sensory quality traits. We compared three feeding treatments, using three groups of 10 male Romane lambs: grazing alfalfa (A), stall-feeding with concentrate and straw (S), and stall-finishing with concentrate and straw for 21 days after previously grazing alfalfa (AS). During stall-feeding, the concentrate was given at a level adjusted to achieve a similar growth pattern in all treatment groups, and the length of the trough was sufficient for all lambs to have access to the feeds at the same time. Lamb live weight and age at slaughter, and carcass conformation and fatness were similar for all treatment groups. Perirenal fat skatole content was lower in AS and S lambs than in A lambs (P < 0.001 and P < 0.05, respectively), and not significantly different between AS and S lambs. Perirenal fat indole and dorsal fat skatole concentrations were lower in AS lambs than in A lambs (P < 0.05 and P < 0.005, respectively), the other pairwise comparisons being not significant. There was no treatment effect on dorsal fat indole content. Longissimus et lumborum muscle colour coordinates differed between pasture-fed and stall-fed lambs, with a lower lightness (P < 0.005) and greater redness and hue angle (P < 0.001 and P < 0.01, respectively) in pasture-fed lambs, but muscle colour coordinates did not differ between A and AS lambs. A 21-d concentrate-based stall-finishing period in lambs previously raised on alfalfa pasture therefore markedly reduced fat indoles concentrations compared to lambs grazed on alfalfa until slaughter but did not change meat colour.

Applying an association weight matrix in weighted genomic prediction of boar taint compounds.

Biological information regarding markers and gene association may be used to attribute different weights for single nucleotide polymorphism (SNP) in genome-wide selection. Therefore, we aimed to evaluate the predictive ability and the bias of genomic prediction using models that allow SNP weighting in the genomic relationship matrix (G) building, with and without incorporating biological information to obtain the weights. Firstly, we performed a genome-wide association studies (GWAS) in data set containing single- (SL) or a multi-line (ML) pig population for androstenone, skatole and indole levels. Secondly, 1%, 2%, 5%, 10%, 30% and 50% of the markers explaining the highest proportions of the genetic variance for each trait were selected to build gene networks through the association weight matrix (AWM) approach. The number of edges in the network was computed and used to derive weights for G (AWM-WssGBLUP). The single-step GBLUP (ssGBLUP) and weighted ssGBLUP (WssGBLUP) were used as standard scenarios. All scenarios presented predictive abilities different from zero; however, the great overlap in their confidences interval suggests no differences among scenarios. Most of scenarios of based on AWM provide overestimations for skatole in both SL and ML populations. On the other hand, the skatole and indole prediction were no biased in the ssGBLUP (S1) in both SL and ML populations. Most of scenarios based on AWM provide no biased predictions for indole in both SL and ML populations. In summary, using biological information through AWM matrix and gene networks to derive weights for genomic prediction resulted in no increase in predictive ability for boar taint compounds. In addition, this approach increased the number of analyses steps. Thus, we can conclude that ssGBLUP is most appropriate for the analysis of boar taint compounds in comparison with the weighted strategies used in the present work.

An unsettling explanation for the failure of skatole-baited ovitraps to capture Culex mosquitoes.

Culex mosquitoes are primarily found in temperate and tropical regions worldwide where they play a crucial role as main vectors of filarial worms and arboviruses. In Recife, a northeast city in Brazil, high densities of Culex quinquefasciatus are often found in association with human populated areas. In marked contrast to another part of the city, field tests conducted in the neighborhood of Sítio dos Pintos showed that trapping of mosquitoes in skatole-baited ovitraps did not differ significantly from captures in control (water) traps. Thus, classical and molecular taxonomic approaches were used to analyze the Culex species circulating in Sítio dos Pintos. Results obtained from both approaches agreed on the cocirculation of Culex quinquefasciatus and Culex nigripalpus in three different areas of this neighborhood. What was initially considered as an unexpected failure of this lure turned out to be a more unsettling problem, that is, the first report in Recife of Culex nigripalpus, a vector of Venezuelan equine encephalitis virus and West Nile virus. Unplanned urbanization processes close to remnants of the Atlantic forest, such as observed in Sítio dos Pintos, may have contributed to the introduction of Cx. nigripalpus in urban areas.

Influence of fresh alfalfa supplementation on fat skatole and indole concentration and chop odour and flavour in lambs grazing a cocksfoot pasture.

We investigated the influence of the level of fresh alfalfa supplementation on fat skatole and indole concentration and chop sensory attributes in grazing lambs. Four groups of nine male Romane lambs grazing a cocksfoot pasture were supplemented with various levels of alfalfa for at least 60days before slaughter. Perirenal fat skatole concentration was higher for lambs that consumed alfalfa than for those that consumed only cocksfoot. The intensity of 'animal' odour in the lean part of the chop and of 'animal' flavour in both the lean and fat parts of the chop, evaluated by a trained sensory panel, increased from the lowest level of alfalfa supplementation onwards and did not increase further with increasing levels of alfalfa supplementation. The outcome of this study therefore suggests that these sensory attributes may reach a plateau when perirenal fat skatole concentration is in the range 0.16-0.24µg/g of liquid fat.

Development of a HPLC/MS/MS methodology for determining 3-O-methyldopa in human plasma and its application in a bioequivalence study

A simple, sensitive and specific HPLC/MS/MS methodology was developed and it was validated for determining 3-O-methyldopa, the major metabolite of dopamine, in human plasma. The separation was achieved on Atlantis T3 C18 analytical column (5 μm; 150 x 4.6 mm i.d.) using a mobile phase consisted of a solution of water and methanol (85:15, v/v) and containing formic acid 0.05 %. The extraction from the analyte and the internal standard sample was performed using a simple protein plasma precipitation with perchloric acid. The detection was conducted on a triple quadrupole tandem mass spectrometer with a positive multiple reaction monitoring mode (MRM). The monitored fragmentation transitions were m/z212.0  m/z 166.0 for 3-O-methyldopa and m/z 227.10  m/z 181.0 for carbidopa (internal standard).The calibration curves were linear in the range of 50–4000 ng/mL for 3-O-methyldopa. The methodology presented a good precision and accuracy in accordance to the criteria for biomedical analysis. And it was successfully applied to the bioequivalence study of two formulations levodopa + benserazide (200 + 50mg) in plasma samples from healthy human volunteers, following the ANVISA guidelines...

Comparative pathologic and stereologic study of respiratory system in mice following administration of 3-methyl indole dissolved in propylene glycol and cremophor EL and LD50 determination

Background: 3-Methyl indole (Skatole, 3-MI) is produced by microfloral fermentation of tryptophan in rumen and production of that has relation with the onset of respiratory problems in cattle. The aim of this study was to compare complications of 3-MI dissolved in two solvents, Cremophor and Propylene Glycol on BALB/c mice by histopathologic and stereologic studies. Materials, Methods & Results: Female Balb/C mice 56 days of age (23 - 27 g) were divided into 13 groups of eight and had access to food and water ad libitum. Mice were housed in plastic cages (4 per cage) with wire bar lids on bedding of sawdust in an air-conditioned room with 12 h light: dark cycles. After a 7-day acclimation period, for 5 groups, Mice were injected with 400, 500, 600, 700 and 800 mg/kg from solution of 3-MI in propylene glycol and similarly for 5 other groups with Cremophor. As well as 2 groups were injected with Propylene glycol and Cremophor with the dosage that is necessary for solving the highest dose of 3-MI. One group received normal saline with the volume equal with Cremophor (drug vehicle) group. Briefly, 125 mg of 3-MI was dissolved per mL of sterile filtered Propylene glycol and 30 mg of 3-MI was dissolved per mL of sterile filtered Cremophor. Once injected intra peritoneally, mice were monitored 3-4 h for external reaction signs from the injection. LD50 was determined 610.16 mg/kg 3-Methylindole and 687.5 mg/kg 3-Methylindole dissolved in Propylene glycol and Cremophor respectively with linear regression. Increase in respiration rate, tachypnea and shallow respiration was observed in clinical examination. In necropsy, alveolar and bronchial hyperemia was significant in lungs. Some superficial wounds were observed in upper respiratory airways. Trachea and Hungarian airways were severely hyperemic. There were some debris’s in airways canals. We couldn’t find any lesion in other organs. Histopathology showed noticeable alveolar edema and emphysema, type I pneumocytes necrosis, Slight endothelial lesions, rare degeneration of type II pneumocytes and raised nutrophil infiltration around vessels were observed in higher dosages of both groups. Moderate interstitial edema, hyperemia and increase of alveolar macrophages were observed too. Increase of lymphocytes was noticed after the dose 600 mg/kg moderately on a dose dependent manner. There was a Hyaline membrane in the wall of air sacs. Endothelial capillary damage in Cremophor dissolved 3-MI groups were slightly lower. Although damage to the vessels was not that much progressed in both groups. Stereologic study of type II pneumocytes showed a significant increase in the percentage of them in alveoli of treatment groups in a dose dependent manner compare to control and drug vehicle groups. At the highest dose (800 mg/kg) the group with Propylene glycol as solvent had significant difference with Cremophor dissolved 3-Methyl indole group and epithelialization was more severe in that. Bronchiole injuries raised in a dose dependent manner in both treatment groups. Discussion: The results of this research indicate that intraperitoneal infusion of 3-MI dissolved in Propylene glycol and Cremophor cause noticeable changes in the respiratory systems of mice. Effects of 3-MI in Propylene glycol is more severe than 3-MI dissolved in Cremophor but type of the lesions is not different. Bronchiolar lesions were moderate compare to the effects of 3-MI in some other animals. Severity of vascular lesions in Propylene glycol dissolved 3-MI was greater than groups that received the Cremophor dissolved 3-MI. Although the vascular injuries were not that much noticeable at all.

Comparative pathologic and stereologic study of respiratory system in mice following administration of 3-methyl indole dissolved in propylene glycol and cremophor EL and LD50 determination

Background: 3-Methyl indole (Skatole, 3-MI) is produced by microfloral fermentation of tryptophan in rumen and production of that has relation with the onset of respiratory problems in cattle. The aim of this study was to compare complications of 3-MI dissolved in two solvents, Cremophor and Propylene Glycol on BALB/c mice by histopathologic and stereologic studies. Materials, Methods & Results: Female Balb/C mice 56 days of age (23 - 27 g) were divided into 13 groups of eight and had access to food and water ad libitum. Mice were housed in plastic cages (4 per cage) with wire bar lids on bedding of sawdust in an air-conditioned room with 12 h light: dark cycles. After a 7-day acclimation period, for 5 groups, Mice were injected with 400, 500, 600, 700 and 800 mg/kg from solution of 3-MI in propylene glycol and similarly for 5 other groups with Cremophor. As well as 2 groups were injected with Propylene glycol and Cremophor with the dosage that is necessary for solving the highest dose of 3-MI. One group received normal saline with the volume equal with Cremophor (drug vehicle) group. Briefly, 125 mg of 3-MI was dissolved per mL of sterile filtered Propylene glycol and 30 mg of 3-MI was dissolved per mL of sterile filtered Cremophor. Once injected intra peritoneally, mice were monitored 3-4 h for external reaction signs from the injection. LD50 was determined 610.16 mg/kg 3-Methylindole and 687.5 mg/kg 3-Methylindole dissolved in Propylene glycol and Cremophor respectively with linear regression. Increase in respiration rate, tachypnea and shallow respiration was observed in clinical examination. In necropsy, alveolar and bronchial hyperemia was significant in lungs. Some superficial wounds were observed in upper respiratory airways. Trachea and Hungarian airways were severely hyperemic. There were some debriss in airways canals. We couldnt find any lesion in other organs. Histopathology showed noticeable alveolar edema and emphysema, type I pneumocytes necrosis, Slight endothelial lesions, rare degeneration of type II pneumocytes and raised nutrophil infiltration around vessels were observed in higher dosages of both groups. Moderate interstitial edema, hyperemia and increase of alveolar macrophages were observed too. Increase of lymphocytes was noticed after the dose 600 mg/kg moderately on a dose dependent manner. There was a Hyaline membrane in the wall of air sacs. Endothelial capillary damage in Cremophor dissolved 3-MI groups were slightly lower. Although damage to the vessels was not that much progressed in both groups. Stereologic study of type II pneumocytes showed a significant increase in the percentage of them in alveoli of treatment groups in a dose dependent manner compare to control and drug vehicle groups. At the highest dose (800 mg/kg) the group with Propylene glycol as solvent had significant difference with Cremophor dissolved 3-Methyl indole group and epithelialization was more severe in that. Bronchiole injuries raised in a dose dependent manner in both treatment groups. Discussion: The results of this research indicate that intraperitoneal infusion of 3-MI dissolved in Propylene glycol and Cremophor cause noticeable changes in the respiratory systems of mice. Effects of 3-MI in Propylene glycol is more severe than 3-MI dissolved in Cremophor but type of the lesions is not different. Bronchiolar lesions were moderate compare to the effects of 3-MI in some other animals. Severity of vascular lesions in Propylene glycol dissolved 3-MI was greater than groups that received the Cremophor dissolved 3-MI. Although the vascular injuries were not that much noticeable at all.(AU)

Culex mosquitoes (Diptera: Culicidae) egg laying in traps loaded with Bacillus thuringiensis variety israelensis and baited with skatole.

The Southern house mosquito, Culex quinquefasciatus, is an important human health pest as a vector of several pathogens, including agents of lymphatic filariasis and arboviruses like West Nile virus. We conducted preliminary experiments in Recife, Brazil, to explore applications of Culex oviposition attractants in combination with Bacillus thuringiensis variety israelensis (Bti) in an attract-and-kill approach. Simple, cost-effective oviposition traps, BR-OVT, loaded with Bti and baited with or without attractant, were deployed in 10 homes for 30 d in 2 consecutive yr. Significantly higher numbers of egg rafts were deposited in traps baited with skatole or infusion than the control water traps. In the first year, 2006, significantly higher numbers of eggs were deposited in infusion-baited traps, particularly in the first 15 d of the experiment, than in skatole traps, but in the following year no significant difference was observed between synthetic and natural attractants. The tests strongly demonstrate that skatole or infusion can be used to enhance the number of egg rafts deposited on Bti-treated oviposition traps.

Phase II in vitro metabolism of 3-methylindole metabolites in porcine liver.

1. The Phase II in vitro metabolism of 3-methylindole (3MI) metabolites was investigated in pigs to determine the possible relationship between 3MI Phase II metabolism and 3MI accumulation in fat. Sulphation and glucuronidation of five of the seven major metabolites found to be produced by porcine microsomes was investigated using porcine cytosol and microsomes, respectively. The possible formation of glutathione conjugates was also investigated using microsomally activated 3MI intermediate(s). 2. No sulphation or glucuronidation was observed for metabolites 3-hydroxy-3-methyloxindole, 3-methyloxindole, indole-3-carbinol or 2-aminoacetophenone; however, 5-hydroxy-3-methylindole (5-OH-3MI) was conjugated with both sulphate and glucuronic acid. 3. The enzyme responsible for sulphation of 5-OH-3MI was identified as the thermostable form of phenol-sulphotransferase (TS-PST) based on its susceptibility to TS-PST inhibitors and the correlation between sulphation of 5-OH-3MI and sulphation of the prototype substrate p-nitrophenol (r = 0.94, p < 0.001). 4. A 3MI-glutathione adduct was identified in microsomal incubations containing 3MI and glutathione. 5. Sulphation of 5-OH-3MI was high in pigs with low levels of 3MI in fat. No relationship was observed between 3MI levels in fat and either glutathione transferase or glucuronidation activities in liver.