Bioaccumulation of lead in different organs of Ctenopharyngodon Idella (grass fish) and Tor putitora (Mahseer) fish / Bioacumulação de chumbo em diferentes órgãos de peixes Ctenopharyngodon idella (carpa-capim) e Tor putitora (Mahseer)

Bioaccumulation of toxic heavy metals in the human body can give rise to adverse health effects, the severity of which depends upon their dosage and duration of exposure. In this study, yearlings of two different species of edible fish, i.e., Tor putitora (Mahseer) and Ctenopharyngodon Idella (grass carp), were exposed to different concentrations of lead nitrate in a controlled environment of aquarium for three different lengths of duration (14, 28, and 60 days). The bioaccumulation of lead in different organs, including gills, skin, muscles, liver, intestine, and swim bladder of the fish, was assessed using atomic absorption spectrometry. Generally, the highest lead concentration was observed in the gills and lowest in the muscles for both species at each experimental dosage and duration. In 14-days exposure, the relative pattern of bioaccumulation in different organs was observed as gill > liver > skin > intestine > swim bladder > muscle for both fish species. Similarly, the pattern of bioaccumulation observed in 28-days exposure was as: gill > liver > intestine > skin > swim bladder > muscle in both species. Whereas, pattern in 60-days exposure was observed as gill > liver > intestine > swim bladder > muscle > skin. The data shows that grass carp had stored higher concentrations of lead than Mahseer, which may be attributed to the fact that they are omnivorous. Furthermore, the lowest bioaccumulation was recorded in the muscles until the 56th day of the exposure, after which the concentration steadily increased in the muscles. The observed pattern highlights the importance of exposure's duration to lead; chronic exposure could result in its bioaccumulation at toxic concentrations in the muscles, which is particularly of concern because the fish muscles are heavily consumed as food worldwide.

A bioacumulação de metais pesados tóxicos no corpo humano pode causar efeitos adversos à saúde, cuja gravidade depende de sua dosagem e duração da exposição. Neste estudo, filhotes de duas espécies diferentes de peixes comestíveis, ou seja, Tor putitora (Mahseer) e Ctenopharyngodon idella (carpa-capim), foram expostos a diferentes concentrações de nitrato de chumbo em um ambiente controlado de aquário por três diferentes períodos de duração (14, 28 e 60 dias). A bioacumulação de chumbo em diferentes órgãos, incluindo brânquias, pele, músculos, fígado, intestino e bexiga natatória dos peixes, foi avaliada por espectrometria de absorção atômica. Geralmente, a maior concentração de chumbo foi observada nas brânquias e a menor nos músculos para ambas as espécies em cada dosagem e duração experimental. Na exposição de 14 dias, o padrão relativo de bioacumulação em diferentes órgãos foi observado como brânquia > fígado > pele > intestino > bexiga natatória > músculo para ambas as espécies de peixes. Da mesma forma, o padrão de bioacumulação observado em 28 dias de exposição foi: brânquia > fígado > intestino > pele > bexiga natatória > músculo em ambas as espécies. Já o padrão de exposição de 60 dias foi observado como brânquia > fígado > intestino > bexiga natatória > músculo > pele. Os dados mostram que a carpa-capim armazenou maiores concentrações de chumbo do que a Mahseer, o que pode ser atribuído ao fato de serem onívoras. Além disso, a menor bioacumulação foi registrada nos músculos até o 56º dia de exposição, após o que a concentração aumentou de forma constante nos músculos. O padrão observado destaca a importância da duração da exposição ao chumbo; a exposição crônica pode resultar em sua bioacumulação em concentrações tóxicas nos músculos, o que é particularmente preocupante porque os músculos dos peixes são muito consumidos como alimento em todo o mundo.

Survey and population dynamics of land snails at Sharkia Governorate, Egypt / Levantamento e dinâmica populacional de caracóis terrestres na província de Sharkia, Egito

Land snails are a destructive agricultural pest in economic crops, but the populations for that pest are highly influenced by temperature and humidity, therefore climatic changes affected their behavior, distribution and population dynamics, for these reasons researchers should follow up on the changes in their behavior, distribution, and population dynamics. In this study, a survey study was conducted to define land snail species existing at Sharkia Governorate, Egypt, from January 2019 to March 2022 in horticultural, vegetable, and field crops and study the population dynamics for the dominant land snail species. Results showed that there are six species of land snails, these species were, Monacha cartusiana, Succinea putris, Eobania vermiculata, Theba pisana, Helicella vestalis, and Cochlicella acuta. The population dynamics of two prevalent land snail species (M. cartusiana and S. putris), were conducted during two successive growing seasons, the Egyptian clover harbored the highest number of M. cartusiana followed by wheat, while the onion was the lowest one during the study period. In the same trends, the land snail S. putris recorded the highest numbers during the growing season of the Egyptian clover crop. Finally, it is concluded that the land snail M. cartusiana considered the first grade of infestation existed everywhere at Sharkia Governorate, and the population density of the land snail is increase gradually after winter till reach the maximum density in spring.

Os caracóis terrestres são pragas agrícolas destrutivas em cultivos econômicos, todavia, as populações dessa praga são altamente influenciadas pela temperatura e umidade, portanto as mudanças climáticas afetam seu comportamento, distribuição e dinâmica populacional, e, por essas razões, os pesquisadores devem acompanhar as mudanças em seu comportamento, distribuição e dinâmica populacional. O presente trabalho foi realizado para definir as espécies de caracóis terrestres existentes na província de Sharkia, no Egito, de janeiro de 2019 a março de 2022 em culturas hortícolas, vegetais e de campo, e estudar a dinâmica populacional das espécies dominantes de caracóis terrestres. Os resultados mostraram que existem seis espécies de caracóis terrestres, essas espécies foram Monacha cartusiana, Succinea putris, Eobania vermiculata, Theba pisana, Helicella vestalis e Cochlicella acuta. A dinâmica populacional de duas espécies predominantes de caracóis terrestres (M. cartusiana e S. putris), foi conduzida durante duas safras sucessivas, o trevo egípcio abrigou o maior número de M. cartusiana seguido pelo trigo, enquanto a cebola foi o menor durante o período de estudo. Seguindo as mesmas tendências, o caracol terrestre S. putris registrou os números mais altos durante a estação de crescimento da cultura do trevo egípcio. Finalmente, conclui-se que o caracol terrestre M. cartusiana, considerado o primeiro grau de infestação, está presente em toda a província de Sharkia, e a densidade populacional do caracol terrestre aumenta gradualmente após o inverno até atingir a densidade máxima na primavera.

Effects of replacement of dietary fish oil with plant oil on growth performance and fatty acid composition of spinefoot rabbitfish, Siganus rivulatus

A 95-day feeding study was carried out to evaluate the impact of complete replacement of fish oil by plant oils in the growth performance, feed consumption fatty acid and body composition of juvenile rabbitfish, Siganus rivulatus. There were four treatments i.e., A (fish oil diet), (linseed oil diet), C (soybean meal oil diet) and D (sunflower oil diet). The experimental trial was conducted in twelve 1.5-m3 fiber glass tanks (n=3). Spinefoot rabbitfish juveniles had an average initial weight of 0.948 g ± 0.124 g and they were stocked at 50 fish per tank. Fish fed diet A showed significantly better growth rate, final body weight, and total body weight than fish fed on the other diets. Moreover, the best FCR was observed for diet A followed by diet C and diets B and D had the worst FCR. Fish body composition for crude protein, dry matter, ashes and gross energy at the end of the trial had not differed between the treatments. The highest polyunsaturated fatty acids (PUFA) was found in fish fed diet A followed in decreasing order by diets D, B, and C. Fish oil is a better dietary lipid source for Spinefoot rabbitfish juveniles, Siganus rivulatus, than plant oils. Among plant oils, soybean oil was better than linseed oil and sunflower oil as the main dietary fat source.

Um estudo de alimentação de 95 dias foi realizado para avaliar o impacto da substituição completa de óleo de peixe por óleos vegetais no desempenho de crescimento, composição corporal e consumo de ração de juvenis de coelho, Siganus rivulatus. Houve quatro tratamentos, ou seja, A (dieta de óleo de peixe), (dieta de óleo de linhaça), C (dieta de óleo de farelo de soja) e D (dieta de óleo de girassol). O ensaio experimental foi conduzido em doze tanques de fibra de vidro de 1,5 m3 (n=3). Os juvenis de peixe-coelho-de-espinho apresentaram peso inicial médio de 0,948 g ± 0,124 g e foram estocados com 50 peixes por tanque. Os peixes alimentados com a dieta A apresentaram taxa de crescimento, peso corporal final e peso corporal total significativamente melhores do que os peixes alimentados com as outras dietas. Além disso, a melhor CAA foi observada para a dieta A seguida da dieta C e as dietas B e D tiveram a pior CA. A composição corporal dos peixes para proteína bruta, matéria seca, cinzas e energia bruta ao final do experimento não diferiu entre os tratamentos. O maior teor de ácidos graxos poliinsaturados (PUFA) foi encontrado nos peixes alimentados com a dieta A seguido em ordem decrescente pelas dietas D, B e C. O óleo de peixe é uma melhor fonte de lipídios dietéticos para juvenis de peixe-coelho, Siganus rivulatus, do que os óleos vegetais. Entre os óleos vegetais, o óleo de soja foi melhor que o óleo de linhaça e o óleo de girassol como principal fonte de gordura da dieta.

Survey and population dynamics of land snails at Sharkia Governorate, Egypt.

Land snails are a destructive agricultural pest in economic crops, but the populations for that pest are highly influenced by temperature and humidity, therefore climatic changes affected their behavior, distribution and population dynamics, for these reasons researchers should follow up on the changes in their behavior, distribution, and population dynamics. In this study, a survey study was conducted to define land snail species existing at Sharkia Governorate, Egypt, from January 2019 to March 2022 in horticultural, vegetable, and field crops and study the population dynamics for the dominant land snail species. Results showed that there are six species of land snails, these species were, Monacha cartusiana, Succinea putris, Eobania vermiculata, Theba pisana, Helicella vestalis, and Cochlicella acuta. The population dynamics of two prevalent land snail species (M. cartusiana and S. putris), were conducted during two successive growing seasons, the Egyptian clover harbored the highest number of M. cartusiana followed by wheat, while the onion was the lowest one during the study period. In the same trends, the land snail S. putris recorded the highest numbers during the growing season of the Egyptian clover crop. Finally, it is concluded that the land snail M. cartusiana considered the first grade of infestation existed everywhere at Sharkia Governorate, and the population density of the land snail is increase gradually after winter till reach the maximum density in spring.

Effects of replacement of dietary fish oil with plant oil on growth performance and fatty acid composition of spinefoot rabbitfish, Siganus rivulatus.

A 95-day feeding study was carried out to evaluate the impact of complete replacement of fish oil by plant oils in the growth performance, feed consumption fatty acid and body composition of juvenile rabbitfish, Siganus rivulatus. There were four treatments i.e., A (fish oil diet), (linseed oil diet), C (soybean meal oil diet) and D (sunflower oil diet). The experimental trial was conducted in twelve 1.5-m3 fiber glass tanks (n=3). Spinefoot rabbitfish juveniles had an average initial weight of 0.948 g ± 0.124 g and they were stocked at 50 fish per tank. Fish fed diet A showed significantly better growth rate, final body weight, and total body weight than fish fed on the other diets. Moreover, the best FCR was observed for diet A followed by diet C and diets B and D had the worst FCR. Fish body composition for crude protein, dry matter, ashes and gross energy at the end of the trial had not differed between the treatments. The highest polyunsaturated fatty acids (PUFA) was found in fish fed diet A followed in decreasing order by diets D, B, and C. Fish oil is a better dietary lipid source for Spinefoot rabbitfish juveniles, Siganus rivulatus, than plant oils. Among plant oils, soybean oil was better than linseed oil and sunflower oil as the main dietary fat source.

Bioaccumulation of lead in different organs of Ctenopharyngodon Idella (grass fish) and Tor putitora (Mahseer) fish.

Bioaccumulation of toxic heavy metals in the human body can give rise to adverse health effects, the severity of which depends upon their dosage and duration of exposure. In this study, yearlings of two different species of edible fish, i.e., Tor putitora (Mahseer) and Ctenopharyngodon Idella (grass carp), were exposed to different concentrations of lead nitrate in a controlled environment of aquarium for three different lengths of duration (14, 28, and 60 days). The bioaccumulation of lead in different organs, including gills, skin, muscles, liver, intestine, and swim bladder of the fish, was assessed using atomic absorption spectrometry. Generally, the highest lead concentration was observed in the gills and lowest in the muscles for both species at each experimental dosage and duration. In 14-days exposure, the relative pattern of bioaccumulation in different organs was observed as gill > liver > skin > intestine > swim bladder > muscle for both fish species. Similarly, the pattern of bioaccumulation observed in 28-days exposure was as: gill > liver > intestine > skin > swim bladder > muscle in both species. Whereas, pattern in 60-days exposure was observed as gill > liver > intestine > swim bladder > muscle > skin. The data shows that grass carp had stored higher concentrations of lead than Mahseer, which may be attributed to the fact that they are omnivorous. Furthermore, the lowest bioaccumulation was recorded in the muscles until the 56th day of the exposure, after which the concentration steadily increased in the muscles. The observed pattern highlights the importance of exposure's duration to lead; chronic exposure could result in its bioaccumulation at toxic concentrations in the muscles, which is particularly of concern because the fish muscles are heavily consumed as food worldwide.

Examining the impacts of 12 weeks of low to moderate-intensity aerobic exercise on depression status in patients with systolic congestive heart failure - A randomized controlled study.

OBJECTIVES: Psychiatric depression disorder is common in patients with systolic congestive heart failure (HF), and both conditions share underlying pathophysiological mechanisms. The incidence rate of depression disorder has clearly increased with the increase in HF manifestations in recent decades. Depression disorder is considered an independent predisposing factor for hospitalization, disturbed functional performance, and high rates of morbidity and mortality in HF patients. This randomized controlled study was designed to examine the impacts of low- to moderate-intensity aerobic exercise training on depression status in patients with systolic congestive HF. METHODS: A total of 46 systolic congestive HF patients with depression (40-60 years of age) were randomized to receive twelve weeks of mild- to moderate-intensity aerobic exercise plus standard medical treatment (exercise group) or standard medical treatment without any exercise intervention (control group). Depression status was examined using the validated Patient Health Questionnaire-9 (PHQ9) pre- and post-intervention at the end of the study program. RESULTS: No significant differences were observed between the exercise and control groups in demographic data or clinical characteristics (p>0.05). Both study groups showed a significant reduction in depression status at the end of the 12-week intervention (p<0.05). The comparison between the mean values of the depression scores showed significant differences between the two groups after 6 and 12 weeks of the intervention, indicating a greater reduction in depression scores in the exercise group than in the control group (p<0.05). CONCLUSIONS: Twelve weeks of a low- to moderate-intensity aerobic exercise program was safe and effective for reducing depression severity in patients with systolic congestive HF. Low- to moderate-intensity aerobic training should be recommended for cardiac patients, particularly those with HF-related depression.

Examining the impacts of 12 weeks of low to moderate-intensity aerobic exercise on depression status in patients with systolic congestive heart failure - A randomized controlled study

OBJECTIVES: Psychiatric depression disorder is common in patients with systolic congestive heart failure (HF), and both conditions share underlying pathophysiological mechanisms. The incidence rate of depression disorder has clearly increased with the increase in HF manifestations in recent decades. Depression disorder is considered an independent predisposing factor for hospitalization, disturbed functional performance, and high rates of morbidity and mortality in HF patients. This randomized controlled study was designed to examine the impacts of low- to moderate-intensity aerobic exercise training on depression status in patients with systolic congestive HF. METHODS: A total of 46 systolic congestive HF patients with depression (40-60 years of age) were randomized to receive twelve weeks of mild- to moderate-intensity aerobic exercise plus standard medical treatment (exercise group) or standard medical treatment without any exercise intervention (control group). Depression status was examined using the validated Patient Health Questionnaire-9 (PHQ9) pre- and post-intervention at the end of the study program. RESULTS: No significant differences were observed between the exercise and control groups in demographic data or clinical characteristics (p>0.05). Both study groups showed a significant reduction in depression status at the end of the 12-week intervention (p<0.05). The comparison between the mean values of the depression scores showed significant differences between the two groups after 6 and 12 weeks of the intervention, indicating a greater reduction in depression scores in the exercise group than in the control group (p<0.05). CONCLUSIONS: Twelve weeks of a low- to moderate-intensity aerobic exercise program was safe and effective for reducing depression severity in patients with systolic congestive HF. Low- to moderate-intensity aerobic training should be recommended for cardiac patients, particularly those with HF-related depression.

Isolation and identification of main mastitis pathogens in Mexico / Isolação e identificação dos micróbios patogênicos principais da mastite em México

The present work is a large epidemiological study aiming to detect the prevalence of subclinical mastitis and to investigate the major udder pathogens in Jalisco State, western Mexico. For this purpose, 2205 dairy cows, representing 33 Mexican dairy herds, were involved. Of 2205 cows, 752 mastitic animals were diagnosed and only 2,979 milk samples could be obtained for further investigation. All 2979 milk samples were subjected to California Mastitis Test (CMT) to differentiate clinical cases from subclinical ones where 1996 samples (67 %) reacted positively. Of these, 1087 samples (54.5%) came from cows suffering from clinical cases of mastitis. Bacteriological identification of the causative agents revealed the presence of a major group of pathogens including the Coagulase negative staphylococci (CNS), S.aureus, S.agalactiae, Corynebacterium spp. and Coliform bacteria which were detected in 464 (15.6%), 175 (5.9%), 200 (6.8%), 417 (14%) and 123 (4.1%) of the 2927 investigated quarters, 295 (15.4%), 118 (15.7%), 111 (14.8%), 227 (30.2%) and 109 (14.5%) of the 752 examined cows and in 33 (100%), 22 (66.7%), 19 (57.6%), 30 (90.1%) and 27 (81.8%) of the 33 herds involved, respectively. Other pathogens could be detected in the investigated milk samples such as S. dysgalactiae (0.4%), S.uberis (0.37%), Bacillus spp. (1%), Nocardia spp. (0.6%) und Candida spp. (0.1%). Meanwhile, others were present in a negligible ratio; including the Aerococcus viridans, and Enterococcus spp., Lactococcus lactis, S. bovis.

O trabalho atual é um estudo epidemiológico que objetiva detectar a predominância da mastite subclínica e investigar os micróbios patogênicos principais do úbere no México ocidental. Com esta finalidade, foram utilizadas 2205 vacas leiteiras, representando 33 rebanhos de leiteiras mexicanas. Além dessas 2205 vacas, 752 animais com mastite foram diagnosticados, considerando-se que somente 2979 amostras do leite poderiam ser obtidas para a posterior investigação. Todas as 2979 amostras do leite foram submetidas ao teste da mastite de Califórnia (CMT) para diferenciar casos clínicos dos subclínicos, visto que 1996 amostras (67%) reagiram positivamente. Além dessas, 1087 amostras (54.5%) vieram das vacas que sofrem de casos clínicos de mastite. A identificação bacteriológica dos agentes causais revelou a presença dos Staphylococcus negativos para coagulase (CNS), S. aureus, S. agalactiae, outros spp. Streptococcal, Corynebacterium spp., e as bactérias de coliformes foram detectadas em 464 (15.6%), 175 (5.9%), 200 (6.8%), 109 (3.9%), 417 (14%) e em 123 (4.1%) dos 2927 quartos investigados; em 295 (15.4%), 118 (15.7%), 111 (14.8%), 95 (12.6%), 227 (30.2%) e em 109 (14.5%) das 752 vacas examinadas e, finalmente, em 33 (100%), 22 (66.7%), 19 (57.6%), 30 (90.1%), 30 (90.1%) e em 27 (81.8%) dos 33 rebanhos envolvidos, respectivamente.

Isolation and identification of main mastitis pathogens in Mexico / Isolação e identificação dos micróbios patogênicos principais da mastite em México

The present work is a large epidemiological study aiming to detect the prevalence of subclinical mastitis and to investigate the major udder pathogens in Jalisco State, western Mexico. For this purpose, 2205 dairy cows, representing 33 Mexican dairy herds, were involved. Of 2205 cows, 752 mastitic animals were diagnosed and only 2,979 milk samples could be obtained for further investigation. All 2979 milk samples were subjected to California Mastitis Test (CMT) to differentiate clinical cases from subclinical ones where 1996 samples (67 %) reacted positively. Of these, 1087 samples (54.5%) came from cows suffering from clinical cases of mastitis. Bacteriological identification of the causative agents revealed the presence of a major group of pathogens including the Coagulase negative staphylococci (CNS), S.aureus, S.agalactiae, Corynebacterium spp. and Coliform bacteria which were detected in 464 (15.6%), 175 (5.9%), 200 (6.8%), 417 (14%) and 123 (4.1%) of the 2927 investigated quarters, 295 (15.4%), 118 (15.7%), 111 (14.8%), 227 (30.2%) and 109 (14.5%) of the 752 examined cows and in 33 (100%), 22 (66.7%), 19 (57.6%), 30 (90.1%) and 27 (81.8%) of the 33 herds involved, respectively. Other pathogens could be detected in the investigated milk samples such as S. dysgalactiae (0.4%), S.uberis (0.37%), Bacillus spp. (1%), Nocardia spp. (0.6%) und Candida spp. (0.1%). Meanwhile, others were present in a negligible ratio; including the Aerococcus viridans, and Enterococcus spp., Lactococcus lactis, S. bovis.(AU)

O trabalho atual é um estudo epidemiológico que objetiva detectar a predominância da mastite subclínica e investigar os micróbios patogênicos principais do úbere no México ocidental. Com esta finalidade, foram utilizadas 2205 vacas leiteiras, representando 33 rebanhos de leiteiras mexicanas. Além dessas 2205 vacas, 752 animais com mastite foram diagnosticados, considerando-se que somente 2979 amostras do leite poderiam ser obtidas para a posterior investigação. Todas as 2979 amostras do leite foram submetidas ao teste da mastite de Califórnia (CMT) para diferenciar casos clínicos dos subclínicos, visto que 1996 amostras (67%) reagiram positivamente. Além dessas, 1087 amostras (54.5%) vieram das vacas que sofrem de casos clínicos de mastite. A identificação bacteriológica dos agentes causais revelou a presença dos Staphylococcus negativos para coagulase (CNS), S. aureus, S. agalactiae, outros spp. Streptococcal, Corynebacterium spp., e as bactérias de coliformes foram detectadas em 464 (15.6%), 175 (5.9%), 200 (6.8%), 109 (3.9%), 417 (14%) e em 123 (4.1%) dos 2927 quartos investigados; em 295 (15.4%), 118 (15.7%), 111 (14.8%), 95 (12.6%), 227 (30.2%) e em 109 (14.5%) das 752 vacas examinadas e, finalmente, em 33 (100%), 22 (66.7%), 19 (57.6%), 30 (90.1%), 30 (90.1%) e em 27 (81.8%) dos 33 rebanhos envolvidos, respectivamente.(AU)

Some optimal culture conditions for production of cyclosporin a by Fusarium roseum

A suitable chemically defined culture medium was selected and some optimal conditions for the production of the highly immunosuppressive compound, cyclosporin A (Cyc A) are reported. Medium of the following composition was favorable for the production of Cyc A by Fusarium roseum: glucose, 30; NaNO3, 2; KH2PO4, 1; MgSO4.7H2O, 0.5 and KCL, 0.5 (g/l). Maximum productivity of Cyc A was achieved at pH 6.0 when 50 ml of the fermentation medium/250 ml flask, inoculated with five fungal agar discs (6 mm, diameter) of 7-days old F. roseum culture after incubation at 30 ºC at 120 rpm for 7 days.

Some optimal culture conditions for production of cyclosporin a by Fusarium roseum.

A suitable chemically defined culture medium was selected and some optimal conditions for the production of the highly immunosuppressive compound, cyclosporin A (Cyc A) are reported. Medium of the following composition was favorable for the production of Cyc A by Fusarium roseum: glucose, 30; NaNO3, 2; KH2PO4, 1; MgSO4.7H2O, 0.5 and KCL, 0.5 (g/l). Maximum productivity of Cyc A was achieved at pH 6.0 when 50 ml of the fermentation medium/250 ml flask, inoculated with five fungal agar discs (6 mm, diameter) of 7-days old F. roseum culture after incubation at 30 ºC at 120 rpm for 7 days.

Pheromone disruption of Argentine ant trail integrity.

Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m(2)) to 1- and 4-m(2) plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected.

Genotyping of Staphylococcus aureus isolated from humans, bovine subclinical mastitis and food samples in Argentina.

The aim of the present study was to characterize genotypically 45 Staphylococcus aureus strains isolated from humans, bovine subclinical mastitis and food samples in Argentina by rep-PCR and PCR amplification of virulence genes. Resistances to various antibiotics could be observed for the human S. aureus, less pronounced for the bovine strains, but not for the eight S. aureus isolated from food samples. The strains could be classified genotypically by rep-PCR and by amplification of the genes encoding protein A, coagulase, clumping factor, the collagen adhesin domains A and B, capsular polysaccharide 5 and 8, the accessory gene regulator agr classes I to III, and the S. aureus gene regulator sae. rep-PCR analyses and the different gene patterns revealed that the strains could be divided into seven groups mostly matching with the origin of the isolates. The present study describes genotypic variations of S. aureus strains isolated from different origins in Argentina. The study provides a valuable insight into molecular specificities of this important pathogen.