Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Caries is a common, chronic and complex multifactorial disease that affects tooth structure, with devastating effects on health and quality of life. In this context, the aim of this paper is to describe early childhood caries, its diagnosis and treatment. The etiology is usually related to habits and lifestyles. These include frequent consumption of sugary foods, fermentable carbohydrates, lack of breastfeeding and/or poor oral hygiene. Genetic factors have an influence on the development of dental caries, as well as access to dental services or situations where immunocompetence is affected. Management of early childhood caries should be oriented toward prevention through the elimination of lifestyles and habits; after onset, measures should be taken to stop counteract the disease process and prevent or slow the progression of carious lesions toward cavitation and tooth destruction. Non-invasive or minimally invasive treatment approaches are preferable as they require fewer resources and represent less trauma to the infant.

Abstract Objective:  To evaluate the plant development of Genipa americana L. and Heliconia stricta Huber associated as an agroforestry system, and their effects on soil fertility. Design/methodology/approach: A completely randomized experimental design with three replications per treatment was used. Genipa plantations were established in july 2019 and Heliconias in september 2020. Soil samples and analyzes were carried out based on the methodologies specified in NOM-021-RECNAT-2000 (SEMARNAT, 2002). Monthly measurements of height, stem diameter, number of leaves, photosynthetic rate was made for Heliconias and Genipa, as well as number of branches and canopy cover for the latter. Means were compared by Tukey's test at a 5% confidence level. Results: The contents of organic material (OM), Phosphorus (P) and Manganese (Mn) in the soil did present significant differences due to the effect of the treatments cultivated alone and/or associated, while the contents of Nitrógeno (N), Potasio (K), Calcio (Ca), Magnesio (Mg), Zinc (Zn) and Cobre (Cu) did not. The behavior and development of the Genipa was the same in the treatments, while the Heliconias did present variations. Study limitations/implications: It is recommended to continue the study. Findings/Conclusions: The treatments cultivated alone and/or associated improved the (OM) contents in the soil. The Genipa is not affected by the effect of the treatments evaluated, while the Heliconias are.

Objective: Conceptually analyze the potential use of water that the technification of gravity irrigation allows to save and generate alternatives of use according to the extrapolation of volumes, both in the same agricultural sector, or outside it. Design/methodology/approach: The Technified Gravity Irrigation Program (RIGRAT) will be evaluated. By measuring the volumes of irrigation used in the Irrigation Districts (DR) 075 Rio Fuerte, 076 Valle del Carrizo and 063 Guasave, Sinaloa, during the 2015-2018 agricultural cycles. The measured and statistical data are integrated for the analysis of volumes saved by the program and its national statistical projection. Results: In 6,114.5 ha under technification of the RIGRAT program in DR 075, the volume saved was 2,401.02 thousand m3 (2.4 hm3). The volume of water saved on that surface represents 10% of the water used by the industrial sector of Sinaloa. It is inferred that the modernization of the DR075 Rio Fuerte in the planted area of 289,780 ha, would imply a saving of 40% of the water that can be used in urban areas of Sinaloa. In the same agricultural sector, it would be possible to save a volume of 187 thousand m3, which means 6.4% of the water used by the irrigation district at plot level. Limitations on study/implications: Current regulations do not allow the transfer of water volume in its different uses, with the aim of optimizing the value of water. Findings/conclusions: With actions implemented in the RIGRAT program, it represents that achieving water savings at the farm level would have a great impact, since agriculture is the main consumer of water and there could be volumes saved to be used in other sectors.  

Objective: To determine the causal agent of powdery mildew in husk tomato and watermelon, as well as its morphological and molecular characterization. Design/methodology/approach: In Iguala, Guerrero, in 2018, leaves with powdery mildew symptoms from husk tomato (Physalis ixocarpa) and watermelon (Citrullus lanatus) were collected. From two isolates (Phyxa1 and Phyxa2) of husk tomato and two of watermelon (Citrus1 and Citrus2), the morphological characterization was carried out by assembling morphological structures and visualizing them under an optical microscope. For molecular characterization, the ITS region was amplified with the use of primers ITS1 and ITS4, PCR was performed and the products obtained were sequenced in the company Macrogen®. A phylogenetic analysis was performed with the resulting sequences and they were compared with other sequences available in GenBank. Results: It was determined that there is morphological and genetic variability between isolates from husk tomato and watermelon. The largest sizes of conidiophores and conidia were from Phyxa1 and Phyxa2 isolates, the smallest sizes were recorded in Citrus1 and Citrus2. The isolates presented a tendency to group according to the host, the Phyxa1 and Phyxa2 isolates were associated with Solanacea isolates, while the Citrus1 and Citrus2 isolates were grouped with isolates of the Cucurbitaceae family. Findings/conclusions: Podosphaera xanthii was shown to be the agent associated with powdery mildew in husk tomato and watermelon. Morphological and genetic variability of P. xanthii was determined, which was associated with the host of origin.

Objective: To evaluate the soil cover with corn-neem biomass for the management of Spodoptera frugiperda, in corn, hybrid INIAP H601, in Pechiche, Los Ríos, Ecuador. Design/methodology/approach: Two treatments were evaluated: one with corn-neem soil cover at 2.0 tn.ha-1 before sowing plus two foliar applications at 10 and 20 days after sowing, and a control without coverage in a completely randomized design, the variables evaluated were the percentage of corn plants with damage between grades one and three, and between grades four and five at 30 days after planting, the Leaf Area Index (LAI) and agricultural yield. Results: Under field conditions, it was shown that in both treatments no significant differences were found in the damages with degrees between one and three with 69.0% of affectation, and yes for the damages with degrees between four and five with 31.0 % in the control and 15.0% in coverage, also with higher IAF and yield as dry grain. There was a linear but inverse relationship between affected plants with grades between 4 and 5 with respect to LAI and yield. Limitations/implications: The availability of neem tree biomass may be a limitation if this technology is to be applied to larger land areas. Findings/conclusions: It was concluded that soil cover with maize-neem plus a foliar application decreased the incidence of Spodoptera frugiperda and increased LAI and agricultural yield.

Objective: To evaluate the reproductive and seminal characteristics of Pelibuey rams infected with Mycobacterium avium subsp. paratuberculosis in the subclinical phase. Design/methodology/approach: In order to determine whether paratuberculosis (PTB) affects the reproductive variables and seminal quality in Pelibuey rams naturally infected with Mycobacterium avium subsp. paratuberculosis (MAP) in the subclinical phase, weekly evaluations were conducted, over a period of two months, of the variables live weight, scrotal circumference, ejaculation latency and seminal characteristics: volume, pH, masal motility and progressive individual motility, concentration, live spermatozoids and dead spermatozoids, in five rams infected by MAP and a further five uninfected rams, of average weight and age 53.58 kg (± 3.26) and 2.91 years (± 0.59), respectively. Results: PTB was not found to affect the reproductive and seminal variables evaluated. Limitations of the study/implications: It would have been convenient to carry out the evaluation of the seminal characteristics for a longer time, however, the sampling was stopped in order to ensure the animal welfare of the rams as far as possible, since they began to show signs of PTB. Findings/Conclusions: The Pelibuey rams diagnosed with PTB in subclinical phase did not present any effect on the reproductive and seminal characteristics. Meanwhile, reproductive management can be carried out with PTB-infected Pelibuey lambs in a subclinical phase.

Objective: To evaluate the effect of reducing the synchronized luteum phase and of applying eCG on reproductive response variables and hormone profile in primiparous and multiparous ewes. Design/methodology/approach: The experimental design was completely randomized with a 2 x 2 x 2 factorial array. Eight-one ewes were divided by their reproductive activity: primiparous (n=38) and multiparous (n=43). The percentage of presentation of estrus and pregnancy were analyzed with a c2 test. The estrus onset and duration for an analysis of variance and the Tukey test of comparison of means. The P4 concentration was performed using the PROC MIXED procedure, which included fixed effects of the treatment and day and the interaction of the two. Results: The response in estrus presentation was not different between treatments, however; the onset and duration of estrus were affected by physiological state and the synchronized luteum phase. P4 concentrations in serum were higher in primiparous ewes than in multiparous ewes. There were no differences in pregnancy rate or prolificity by principal effects. Limitations on study/implications: The estrus onset and duration varied by effects of the reproductive physiological status and the duration of the synchronized luteum phase (6 and 12 d), Therefore, it must be taken into account when artificial insemination is performed at a fixed time. Findings/conclusions: The combination of cronolone sponges with 100 IU eCG during short (6 d) are effective for the synchronization of estrous. The P4 concentrations in serum were higher in primiparous ewes, but this was not determinant for increasing gestation and prolificity in treated ewes.

The objective was to estimate production costs and profitability of maize silage and stubble maize as a feeding strategy for cattle in dry seasons in the southern region of the State of Mexico. 30 semi-structured surveys with non-probabilistic sampling were applied during the spring/summer 2020 cycle. Socioeconomic variables, profitability threshold and the benefit/cost ratio were analyzed. The production units were characterized as small, the average age of producers did not exceed 45 years and nine years dedicated to production. The average production of corn silage and stubble corn was 28 and 7.20 tons with a cost of 1.278.40 and 3.587.23 pesos per ton. The benefit/cost ratio in silage and stubble corn was 0.46 and 0.16. It is concluded that both activities were profitable with a predominance of corn silage.  

Objective: To describe some considerations about the nutritional and antimetanogenic potential of four tropical leguminous plants present in Campeche, Mexico: Bauhinia divaricata, Dalbergia glabra, Piscidia piscipula and Caesalpinia vesicaria, in domestic ruminants. Design/methodology/approach: The information was obtained from databases and repositories available on the internet, as well as from official websites of national and international organizations. Results: Although there is vast information of several leguminous species, data still is limited for B. divaricata, D. glabra, P. piscipula and C. vesicaria, despite they are consumed by domestic ruminants. The few available studies report that these species have between 11 and 18% of crude protein (PC) and the presence of some secondary metabolites; however, there is no information regarding their antimetanogenic potential and animal productivity. Limitations of the study/implications: This study provides an overview of the nutritional and antimethanogenic potential of four species of tropical leguminous plants in domestic ruminants in Campeche. Findings/conclusions: B. divaricata, D. glabra, P. piscipula and C. vesicaria are leguminous plans that grow in the Yucatan Peninsula, are found in grazing areas and consumed by domestic ruminants; however, there are few reports that determine the nutritional value of their edible components and none that evaluate their effect on animal productivity and their ability to decrease rumen production of methane (CH4).

Our objective was to determine the cause of the low response in the exclusive use of prostaglandin in synchronization programs in cows under tropical grazing compared to the use of progesterone (CIDR). Thirty-five cows with the presence of CL were randomly distributed: first group (GPG; n=23), synchronized with two doses of PGF2α (25 mg, Dinoprost®), with an interval of 12 days. The second group (GCIDR; n=12) synchronized with an intravaginal device (1.9 g progesterone), 2 mg estradiol benzoate and 50 mg progesterone), at day 7 a dose of PGF2α (pm) was administered and at day 8 the CIDR (am) was withdrawn. CL regression, luteolitic failure, progesterone concentration and CL size were determined. The data were subjected to normality test, then to Mann-Whitney U test or independent t student test and chi square. Finding that only 82.6% (19/23) of GPG cows at the second dose of prostaglandins have functional CL (<1 ng/ml of progesterone). Obtaining only in 43.5% of the cows a regression of the CL in the GPG, vs. 91.7% in GCIDR (P=0.0001). In addition, GPG cows showed luteolytic failure of 39.1% and asynchrony of 17.4%. It is concluded, a low efficiency of prostaglandins on the synchrony and regression of CL (luteolitic failure) in cows fed under tropical grazing, attributed to the low efficiency in synchronization programs.