Evaluación de la carga de bacterias heterótrofas y vibrios en un sistema de cultivo integrado camarón-molusco-macroalga

The load of heterotrophic bacteria and Vibrio spp. were evaluated in an integrated culture system of Litopenaeus vannamei Boone 1931, Mytella guyanensis Lamarck 1819 y Gracilaria vermiculophylla (Ohmi)Papenfuss, lasting for 45 days. The concentrations of heterotrophic bacteria were statistically similar at the beginning and at the end of the integrated culture and non-integrated culture (control), within a rangefrom 106 to 107 CFU/mL; however, at the end, the total counts of vibrios in non-integrated culture were significantly higher than in an integrated culture, up to 8.8×104 UFC/mL. The integrated culture systems showed the capability to maintain load low levels of heterotrophic bacteria without detriment of the shrimp survival, reducing additionally the load of Vibrio spp.Se evaluó la carga de bacterias heterótrofas y Vibrio spp. en un cultivo integrado con Litopenaeus vannamei Boone 1931, Mytella guyanensis Lamarck 1819 y Gracilaria vermiculophylla (Ohmi) Papenfuss, llevado a cabo durante 45 días. La concentración de bacterias heterótrofas fue estadísticamente similar al inicio y final de los cultivos integrados y no integrados (control); con un intervalo de 106 a 107 UFC/mL. Sin embargo, las cuentas totales de Vibrio spp. fueron significativamente más altas en los cultivos no integrados, al final de los mismos con 8.8×104 UFC/mL. Los sistemas de cultivo integrados presentaron lacapacidad de mantener niveles bajos de carga bacteriana heterótrofa sin detrimento en la supervivencia de L. vannamei, además de reducir los niveles de vibrio

Budget and discharges of nutrients to the Gulf of California of a semi-intensive shrimp farm (NW Mexico)

A previous study conducted in 1998 assessed yearly nutrient discharge by the Sinaloa and Sonora shrimp farms to the coastal areas of the Gulf of California (1,509.4 and 438.7 tons of N and P corresponding to 2.1 and 1.05% of the total nutrient discharges to the Gulf along those two states coastlines). However, that estimate did not take into account other nutrient sources, nor the high daily water exchanges of the farms of Sonora, that are likely to increase the calculated amount of nutrients discharged. The evaluation of the nutrient budget of one semi-intensive shrimp farm of Sonora, including the nutrient sources not measured in other studies, showed that during one production cycle this farm discharged 547 kg N·ha-1 and 73 kg P·ha-1, with respective net exports of 122 kg N·ha-1 and 14 kg P·ha-1. Based on the results of this study, the recalculated totals for Sinaloa and Sonora, including rivers, agricultural runoff, and urban wastewater were 77,007.7 and 38,108.3 tons of N and P, and those of shrimp farms 3,556 tons of N and 620.7 tons of P (4.8 and 1.6%). The total discharges of 2003 may be estimated at 78,798.2 and 38,874.1 tons of N and P. In view of its high groth rate, the contributions of shrimp culture would be 10.1% and 3.3%

SUSTITUCIÓN PARCIAL DE HARINA DE SARDINA CON Moringa oleifera EN ALIMENTOS BALANCEADOS PARA JUVENILES DE TILAPIA (Oreochromismossambicus x Oreochromisniloticus) CULTIVADA EN AGUA DE MAR

El incremento en la demanda de pescado para consumo humano ha ocasionado que los cultivos se intensifiquen y la demanda de alimentos balanceados para acuicultura se incremente. La moringa (Moringa oleifera) representa una alternativa como ingrediente para sustituir parcialmente la harina de pescado en alimentos balanceados para tilapia, debido a su contenido de proteína y carbohidratos, pero no ha sido evaluado para tilapia cultivada en agua de mar. En el presente trabajo se muestran los resultados de la inclusión de harina de moringa en el crecimiento de tilapia (O. mossambicus x O. niloticus) cultivada en agua de mar y su digestibilidad in vivo. En el alimento balanceado, se incluyó harina de hoja de M. oleifera, sustituyendo 0, 10, 20 y 30 % de la proteína de la harina de sardina, los resultados sugieren que este ingrediente puede sustituir hasta en un 20% a la proteína de la harina de sardina, sin afectar el crecimiento de la tilapia. La digestibilidad de la proteína de la harina de moringa fue de 89 %. Se concluye que la harina de moringa puede ser incluida en el alimento sustituyendo parcialmente a la harina de sardina sin afectar el crecimiento de juveniles de tilapia roja

Physicochemical properties of cowpea (Vigna unguiculata L. Walp.) meals and their apparent digestibility in white shrimp (Litopenaeus vannamei Boone).

The effect of different feed processing methods on the physicochemical properties, and apparent digestibility of cowpea (Vigna unguiculata) meals as ingredients in diets for white shrimp ( Litopenaeus vannamei ) was investigated. Five experimental cowpea meals were prepared: whole raw (WRC), dehulled (DC), cooked (CC), germinated (GC) and extruded (EXC). The physicochemical properties of the meals were evaluated using differential scanning calorimetry. The meals were included at 15 % in diets for L. vannamei (15.4 g) to determine firmness of pellets and in vivo digestibility of nutrients by using chromic oxide as inert marker. Six diets were evaluated: a control diet, and five diets containing the different cowpea meals. Transition enthalpy significantly decreased after thermal treatment, from 6.1 J/g in WRC to 1.4 J/g in CC, and disappeared in EXC. Firmness of pellets varied from 1.1 N in the EXC diet to 2.8 N in the WRC diet. A significant negative correlation between transition enthalpy and carbohydrate digestibility was found. Dry matter, protein, carbohydrate and lipid digestibility of cowpea meals significantly increased after germinating, cooking or extruding. It is concluded that germinated, cooked and extruded cowpea meals are highly digestible for shrimp and that enthalpy of transition is negatively correlated with the digestibility of carbohydrates

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For schoolaged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

Effect of commercial probiotics addition in a biofloc shrimp farm during the nursery phase in zero water exchange

In biofloc technology systems (BFT) the bacterial community plays the most important role at recycling the organic matter and metabolizing the toxic nitrogenous compounds. The aim of this study was to evaluate the effect of two groups of commercial probiotics on the abundance of viable heterotrophic bacteria (VHB), ammonia oxidizing bacteria (AOB) and Vibrio-like (VLB), nitrogenous compounds and productive parameters of whiteleg shrimp Litopenaeus vannamei in a commercial farm. The study was developed during nursery phase in zero water exchange. Two groups of probiotics (PB1 and PB2) and one control (PBN; no probiotic) were evaluated in three replics. Shrimp postlarvae (7.3 mg) were stocked in ponds (70 m3) at densities of 500 in./m2. Commercial probiotics (Efinol PT-Lab. Robles and Epicin ponds-Epicin hatcheries) were incubated for 36 h in bioreactors (1 m3) and supplied every 3 d in PB1 and PB2 treatments. Basic variables of water quality, nitrogenous compounds and bacterial groups were monitored. At the beginning of the experiment, the abundance of VHB was lower in the PBN treatment, but as the bioassay progressed, the densities were similar to PB1 and PB2. In general VLB showed similar tendency to VHB, but significant difference were determined among treatments. The AOB abundance was similar in all treatments. Nitrogenous compounds and productive parameters of shrimp did not show significant differences between treatments. In the PBN ponds the zero water exchange could have promoted benefical bacteria of the natural biota. The addition of probiotics did not improve the water quality nor productive response of L. vannamei. Keywords: Ammonia oxidizing bacteria, Biofloc, Heterotrophic bacteria, Shrimp nursery, Probiotics, Vibrio-like bacteri