A Polyherbal Mixture with Nutraceutical Properties for Ruminants: A Meta-Analysis and Review of BioCholine Powder.

BioCholine Powder is a polyherbal feed additive composed of Achyrantes aspera, Trachyspermum ammi, Azadirachta indica, and Citrullus colocynthis. The objective of this study was to analyze published results that support the hypothesis that the polyherbal product BioCholine Powder has rumen bypass choline metabolites through a meta-analysis and effect size analysis (ES). Using Scopus, Web of Science, ScienceDirect, PubMed, and university dissertation databases, a systematic search was conducted for experiments published in scientific documents that evaluated the effects of BioCholine supplementation on the variables of interest. The analyzed data were extracted from twenty-one publications (fifteen scientific articles, three abstracts, and three graduate dissertations available in institutional libraries). The studies included lamb growing-finishing, lactating ewes and goats, calves, and dairy cows. The effects of BioCholine were analyzed using random effects statistical models to compare the weighted mean difference (WMD) between BioCholine-supplemented ruminants and controls (no BioCholine). Heterogeneity was explored, and three subgroup analyses were performed for doses [(4 (or 5 g/d), 8 (10 g/d)], supplementation in gestating and lactating ewes (pre- and postpartum supplementation), and blood metabolites by species and physiological state (lactating goats, calves, lambs, ewes). Supplementation with BioCholine in sheep increased the average daily lamb gain (p < 0.05), final body weight (p < 0.01), and daily milk yield (p < 0.05) without effects on intake or feed conversion. Milk yield was improved in small ruminants with BioCholine prepartum supplementation (p < 0.10). BioCholine supplementation decreased blood urea (p < 0.01) and increased levels of the liver enzymes alanine transaminase (ALT; p < 0.10) and albumin (p < 0.001). BioCholine doses over 8 g/d increased blood glucose, albumin (p < 0.10), cholesterol, total protein, and globulin (p < 0.05). The ES values of BioCholine in retained energy over the control in growing lambs were +7.15% NEm (p < 0.10) and +9.25% NEg (p < 0.10). In conclusion, adding BioCholine Powder to domestic ruminants' diets improves productive performance, blood metabolite indicators of protein metabolism, and liver health, showing its nutraceutical properties where phosphatidylcholine prevails as an alternative that can meet the choline requirements in ruminants.

Meta-analysis of flavonoids use into beef and dairy cattle diet: Performance, antioxidant status, ruminal fermentation, meat quality, and milk composition.

The objective of this study was to evaluate the effects of dietary supplementation with flavonoids (FLAs) on animal performance, diet digestibility, antioxidant status in blood serum, rumen parameters, meat quality, and milk composition in beef and dairy cattle through a meta-analysis. Thirty-six peer-reviewed publications were included in the data set. The weighted mean differences (WMD) between the FLAs treatments and the control treatment were used to assess the effect size. Dietary supplementation with FLAs decreased feed conversion ratio (WMD = -0.340 kg/kg; p = 0.050) and increased (p < 0.05) dry matter intake (WMD = 0.191 kg/d), dry matter digestibility (WMD = 15.283 g/kg of DM), and daily weight gain (WMD = 0.061 kg/d). In blood serum, FLAs supplementation decreased the serum concentration of malondialdehyde (WMD = -0.779 nmol/mL; p < 0.001) and increased (p < 0.01) the serum concentration of superoxide dismutase (WMD = 8.516 U/mL), glutathione peroxidase (WMD = 12.400 U/mL) and total antioxidant capacity (WMD = 0.771 U/mL). A higher ruminal propionate concentration (WMD = 0.926 mol/100 mol; p = 008) was observed in response to FLAs supplementation. In meat, the dietary inclusion of FLAs decreased (p < 0.05) shear force (WMD = -1.018 kgf/cm2), malondialdehyde content (WMD = -0.080 mg/kg of meat), and yellowness (WMD = -0.460). Supplementation with FLAs decreased milk somatic cell count (WMD = -0.251 × 103 cells/mL; p < 0.001) and increased (p < 0.01) milk production (WMD = 1.348 kg/d), milk protein content (WMD = 0.080/100 g) and milk fat content (WMD = 0.142/100 g). In conclusion, dietary supplementation with FLAs improves animal performance and nutrient digestibility in cattle. In addition, FLAs improve the antioxidant status in blood serum and the quality of meat and milk.

Effect of the Supplementation Using an Herbal Mixture as a Choline Source during Early Gestation in Rambouillet Ewes.

Previous research indicates that adequate choline nutrition during late gestation improves fetal development. However, there is a lack of studies describing choline's role during early gestation. Thus, the current study hypothesizes that an herbal mixture as a source of choline (Biocholine) positively affects offspring development from ewes supplemented during early gestation. Therefore, the objectives were to evaluate the impact of biocholine on the programming of the offspring early in life through the evaluation of dams and newborn performance. Twenty-eight four-year-old Rambouillet ewes were assigned randomly to two treatments: non-supplementation and 4 gd-1 of biocholine during the early gestation. Compared with the dams without supplementation, the ewes supplemented using biocholine showed no increase in parameters such as birth and weaning weight (p > 0.05). Additionally, the milk yield and quality of colostrum and milk did not present statistical differences (p > 0.05). However, the placental membrane development was reduced in the ewes that received supplementation with biocholine; interestingly, those dams increased the weight of the newborns during the lambing period (p < 0.05). Finally, the current study proposes necessary elucidation of how placental size is programmed and if less placental development has potential benefits in the fetus's development.

Essential Oils as a Dietary Additive for Small Ruminants: A Meta-Analysis on Performance, Rumen Parameters, Serum Metabolites, and Product Quality.

There is an increasing pressure to identify natural feed additives that improve the productivity and health of livestock, without affecting the quality of derived products. The objective of this study was to evaluate the effects of dietary supplementation with essential oils (EOs) on productive performance, rumen parameters, serum metabolites, and quality of products (meat and milk) derived from small ruminants by means of a meta-analysis. Seventy-four peer-reviewed publications were included in the data set. Weighted mean differences (WMD) between the EOs treatments and the control treatment were used to assess the magnitude of effect. Dietary inclusion of EOs increased (p < 0.05) dry matter intake (WMD = 0.021 kg/d), dry matter digestibility (WMD = 14.11 g/kg of DM), daily weight gain (WMD = 0.008 kg/d), and feed conversion ratio (WMD = −0.111). The inclusion of EOs in small ruminants' diets decreased (p < 0.05) ruminal ammonia nitrogen concentration (WMD = −0.310 mg/dL), total protozoa (WMD = −1.426 × 105/mL), methanogens (WMD = −0.60 × 107/mL), and enteric methane emissions (WMD = −3.93 L/d) and increased ruminal propionate concentration (WMD = 0.726 mol/100 mol, p < 0.001). The serum urea concentration was lower (WMD = −0.688 mg/dL; p = 0.009), but serum catalase (WMD = 0.204 ng/mL), superoxide dismutase (WMD = 0.037 ng/mL), and total antioxidant capacity (WMD = 0.749 U/mL) were higher (p < 0.05) in response to EOs supplementation. In meat, EOs supplementation decreased (p < 0.05) the cooking loss (WMD = −0.617 g/100 g), malondialdehyde content (WMD = −0.029 mg/kg of meat), yellowness (WMD = −0.316), and total viable bacterial count (WMD = −0.780 CFU/g of meat). There was higher (p < 0.05) milk production (WMD = 0.113 kg/d), feed efficiency (WMD = 0.039 kg/kg), protein (WMD = 0.059 g/100 g), and lactose content in the milk (WMD = 0.100 g/100 g), as well as lower somatic cell counts in milk (WMD = −0.910 × 103 cells/mL) in response to EOs supplementation. In conclusion, dietary supplementation with EOs improves productive performance as well as meat and milk quality of small ruminants. In addition, EOs improve antioxidant status in blood serum and rumen fermentation and decrease environmental impact.

Application of an Electronic Nose and HS-SPME/GC-MS to Determine Volatile Organic Compounds in Fresh Mexican Cheese.

Electronic devices have been used to describe chemical compounds in the food industry. However, there are different models and manufacturers of these devices; thus, there has been little consistency in the type of compounds and methods used for identification. This work aimed to determine the applicability of electronic nose (e-nose) Cyroanose 320 to describe the differentiation of volatile organic compounds (VOCs) in fresh Mexican cheese (F-MC) formulated with milk from two different dairy cattle breeds. The VOCs were described using a device manufactured by Sensigent and Solid-Phase Micro-extraction (SPME) coupled to GC-MS as a complementary method. The multivariate principal components analysis (PCA) and the partial least squares discriminant analysis (PLS-DA) were used to describe the relationships of VOCs to electronic nose data, sensory data, and response levels. In addition, variable importance in projection (VIP) was performed to characterize the e-nose signals to the VOCs. The e-nose distinguishes F-MC prepared with milk from two dairy breeds. Sensor number 31 correlated with carboxylic acids most in F-MC from Jersey milk. The HS-SPME/GC-MS identified eighteen VOCs in F-MC made with Holstein milk, while only eleven VOCs were identified for F-MC made with Jersey milk. The more significant peaks in both chromatogram analyses were Propanoic acid, 2-methyl-, 1-(1,1-dimethylethyl)-2-methyl-1,3-propanediyl ester in cheese made from Holstein milk and Propanoic acid, 2-methyl-, 3-hydroxy-2,4,4-trimethylpentyl ester in Jersey milk cheese. Both compounds are considered essential carboxylic acids in the dairy industry. Thus, sensor 31 in the electronic nose Cyranose 320 increased its response by essential carboxylic acids identified by HS-SPME/GC-MS as a complementary method. The e-nose Cyranose 320 is potentially helpful for evaluating fresh Mexican cheese authentication independent of cows' milk samples from different breeds.

Effects of a Polyherbal Dietary Additive on Performance, Dietary Energetics, Carcass Traits, and Blood Metabolites of Finishing Lambs.

The objective of this study was to evaluate the effects of dietary supplementation of a polyherbal additive (PA) containing hydrolyzable tannins, flavonoids, and essential oils on productive performance, dietary energetics, carcass and meat characteristics, and blood metabolites of lambs in their finishing phase. Twenty-eight Pelibuey × Katahdin lambs (20.52 ± 0.88 kg body weight (BW)) were housed in individual pens and assigned to four treatments (n = 7) with different doses of PA: 0 (CON), 1 (PA1), 2 (PA2), and 3 (PA3) g of PA kg−1 of DM for 56 days. Compared to the CON, lambs in PA1 treatment had higher average daily gain (p = 0.03), higher dietary energy utilization (p = 0.01), greater backfat thickness (p = 0.02), greater Longissimus dorsi muscle area (p = 0.01), and better feed conversion ratio (p = 0.02). PA supplementation did not affect (p > 0.05) dry matter intake, carcass yield, biometric measures, and meat chemical composition. All hematological and most of the blood biochemical parameters were similar in lambs of all treatments (p > 0.05). However, compared to the CON, lambs assigned to the PA3 treatment had lower serum urea concentration (p = 0.05) and higher serum albumin concentration (p = 0.03). In conclusion, low doses of PA could be used as a growth promoter in finishing lambs without affecting dry matter intake, carcass yield, meat chemical composition, and health status of the lambs. However, more in vivo research is needed to better understand the impact of bioactive compounds from PA used on productivity, metabolism, and health status of finishing lambs.

Influence of a Polyherbal Choline Source in Dogs: Body Weight Changes, Blood Metabolites, and Gene Expression.

Choline chloride is used to provide choline in dog foods; however, in other domestic species, it has been replaced with a polyherbal containing phosphatidylcholine. A polyherbal containing Achyrantes aspera, Trachyspermum ammi, Citrullus colocynthis, Andrographis paniculata, and Azadirachta indica was evaluated in adult dogs through body weight changes, subcutaneous fat thickness, blood metabolites, and gene expression. Forty dogs (4.6 ± 1.6 years old) who were individually housed in concrete kennels were randomly assigned to the following treatments: unsupplemented diet (377 mg choline/kg), choline chloride (3850 mg/kg equivalent to 2000 mg choline/kg diet), and polyherbal (200, 400, and 800 mg/kg) for 60 days. Blood samples were collected on day 59 for biochemistry, biometry, and gene expression analysis through microarray assays. Intake, final body weight, and weight changes were similar for the two choline sources. Feed intake variation among dogs (p = 0.01) and dorsal fat (p = 0.03) showed a quadratic response to herbal choline. Dogs that received the polyherbal diet had reduced blood cholesterol levels (Quadratic, p = 0.02). The gene ontology analysis indicated that 15 biological processes were modified (p ≤ 0.05) with implications for preventing cardiovascular and metabolic diseases, cancer prevention, inflammatory and immune response, and behavior and cognitive process. According to these results that were observed in a 60 day trial, the polyherbal form could replace choline chloride in dog diets at a concentration of 400 mg/kg.

Growth Performance, Meat Quality and Antioxidant Status of Sheep Supplemented with Tannins: A Meta-Analysis.

The objective of this study was to evaluate the effects of dietary supplementation with tannins (TANs) on productive performance, carcass characteristics, meat quality, oxidative stability, and blood serum antioxidant capacity of sheep through a meta-analysis. Using Scopus, Web of Science, ScienceDirect, and PubMed databases, a systematic search was performed for studies published in scientific journals that investigated the effects of TANs supplementation on the variables of interest. Only studies with weaned or older sheep were included. The data analyzed were extracted from 53 peer-reviewed publications. The sheep included in the present study were between 2 and 6 months old, and between 12 and 31 kg of body weight. The effects of TANs were analyzed using random-effects statistical models to examine the standardized mean difference (SMD) between treatments with TANs and control (no TANs). Heterogeneity was explored by meta-regression and a subgroup analysis was performed for covariates that were significant. Supplementation with TANs did not affect dry matter intake, pH, color (L* and b*), Warner-Bratzler shear force, cooking loss and meat chemical composition (p > 0.05). Supplementation with TANs increased daily weight gain (SMD = 0.274, p < 0.05), total antioxidant capacity (SMD = 1.120, p < 0.001), glutathione peroxidase enzyme activity (SMD = 0.801, p < 0.001) and catalase (SMD = 0.848, p < 0.001), and decreased malondialdehyde (MDA) concentration in blood serum (SMD = -0.535, p < 0.05). Supplementation with TANs decreased feed conversion rate (SMD = -0.246, p < 0.05), and the concentration of MDA (SMD = -2.020, p < 0.001) and metmyoglobin (SMD = -0.482, p < 0.05) in meat. However, meat redness (SMD = 0.365), hot carcass yield (SMD = 0.234), cold carcass yield (SMD = 0.510), backfat thickness (SMD = 0.565) and the Longissimus dorsi muscle area (SMD = 0.413) increased in response to TANs supplementation (p < 0.05). In conclusion, the addition of tannins in sheep diets improves productive performance, antioxidant status in blood serum, oxidative stability of meat and some other characteristics related to meat and carcass quality.

Potential Effects of Delphinidin-3-O-Sambubioside and Cyanidin-3-O-Sambubioside of Hibiscus sabdariffa L. on Ruminant Meat and Milk Quality.

The objective was to review the potential effects of adding anthocyanin delphinidin-3-O-sambubioside (DOS) and cyanidin-3-O-sambubioside (COS) of HS in animal diets. One hundred and four scientific articles published before 2021 in clinics, pharmacology, nutrition, and animal production were included. The grains/concentrate, metabolic exigency, and caloric stress contribute to increasing the reactive oxygen species (ROS). COS and DOS have antioxidant, antibacterial, antiviral, and anthelmintic activities. In the rumen, anthocyanin might obtain interactions and/or synergisms with substrates, microorganisms, and enzymes which could affect the fiber degradability and decrease potential methane (CH4) emissions; since anthocyanin interferes with ruminal fatty acids biohydrogenation (BH), they can increase the n-3 and n-6 polyunsaturated fatty acids (PUFA), linoleic acid (LA), and conjugated linoleic acid (CLA) in milk and meat, as well as improving their quality. Anthocyanins reduce plasma oxidation and can be deposited in milk and meat, increasing antioxidant activities. Therefore, the reduction of the oxidation of fats and proteins improves shelf-life. Although studies in ruminants are required, COS and DOS act as inhibitors of the angiotensin-converting enzyme (ACEi) and rennin expression, regulating the homeostatic control and possibly the milk yield and body weight. By-products of HS contain polyphenols as calyces with positive effects on the average daily gain and fat meat quality.

Growth Performance, Carcass Characteristics, and Blood Metabolites of Lambs Supplemented with a Polyherbal Mixture.

The objective of this study was to determine the effects of the supplementation of a polyherbal mixture (HM) on the productive performance, carcass characteristics, meat quality, and the profile of blood metabolites of lambs fed a high-concentrate diet. Thirty-six male Pelibuey lambs (25.21 ± 0.96 kg BW) were housed in individual pens during a 56-day feeding period and were randomly assigned to four treatments: (1) Control (CON): Basal diet without HM; (2) HM1: CON + 1 g of HM kg-1 dry matter (DM); (3) HM2: CON + 2 g of HM kg-1 DM; and (4) HM3: CON + 3 g of HM kg-1 DM. Data were analyzed using the GLM (General Linear Model) procedure of statistical analysis system (SAS), and linear and quadratic effects were tested to evaluate the effects of the HM level. A quadratic increase was observed in the dry matter intake and in daily weight gain (p < 0.05) of lambs fed with HM2 and HM1, respectively. However, final body weight, body condition, carcass characteristics, and meat quality were similar among treatments (p > 0.05). It was observed a linear increase (p < 0.05) in the mean corpuscular hemoglobin concentration. Lymphocytes in blood from lambs supplemented with the HM1 diet increased and segmented neutrophils decreased compared to lambs receiving the CON treatment (p < 0.05). The concentration of uric acid in the blood had a linear increase (p < 0.05) and the serum creatinine level decreased (p < 0.05) as the HM dietary dose increased. In conclusion, dietary inclusion of 2 and 1 g of HM kg-1 of DM improves feed consumption and daily weight gain, respectively, without affecting carcass characteristics, meat quality, and health status on finishing lambs.

Supplemental Herbal Choline Increases 5-hmC DNA on Whole Blood from Pregnant Ewes and Offspring.

Herbal formulas during pregnancy have been used in developing countries. Despite that, the potential effects on the mother and offspring and whether those supplements elicit epigenetic modifications is still unknown. Therefore, our objectives were to determine the effects of supplemental herbal choline source (BCho) on the percentage of 5-hmC in whole blood from gestating ewes and their offspring, as well as determining the milk quality and growth of the offspring. Thirty-five gestating Rambouillet ewes were randomly assigned to five treatments: T1, supplementation of 4 g per day (gd-1) of BCho during the first third of gestation; T2, supplementation of 4 gd-1 of BCho during the second third of gestation; T3, supplementation of 4 gd-1 of BCho during the last third of gestation; T4, supplementation of 4 gd-1 of BCho throughout gestation; and T5, no BCho supplementation (control). For the 5-hmC DNA analysis, whole blood from ewes was sampled before pregnancy and at each third of gestation (50 days). Whole blood from lambs was sampled five weeks after birth. The evaluation of the nutritional programming effects was conducted through the percentages of 5-hmC in the lambs. Compared with other treatments, the whole blood from ewes supplemented during T1 and T4 had the greatest 5-hmC percentages (p < 0.05). However, only ewes fed BCho throughout gestation (T4) maintained the greatest percentages of 5-hmC (p < 0.05). The lamb growth performance indicated that the BCho maternal supplementation did not affect the nutritional programming. However, the lambs born from ewes supplemented during T2 had the greatest 5-hmC percentages (p < 0.05). Our data suggest that ewes supplemented during T4 with BCho increase and maintain the percentages of 5-hmC in whole blood, and the offspring born from ewes supplemented with BCho during T2 maintained the greatest percentages of 5-hmC 35 d after they were born.

Influence of a Polyherbal Mixture in Dairy Calves: Growth Performance and Gene Expression.

A polyherbal feed mixture containing (Achyrantes aspera, Trachyspermum ammi, Citrullus colocynthis, Andrographis paniculata, and Azadirachta indica) was evaluated in growing calves through blood chemistry, blood biometry, and gene expression during the pre-ruminant to weaning period. Forty Holstein calves (initial BW 45.6 ± 3.2 kg; 22.8 ± 0.9 days post birth) from a dairy farm were randomly assigned to the following treatments: 0, 3, 4, and 5 g/d of a polyherbal mixture, dosed in colloid gels with gelatin. Calves were housed in individual outdoor boxes with ad libitum access to a 21.5% CP calf starter and water and fed individually with a mixture of milk and a non-medicated milk replacer (22% CP). Blood samples were collected on day 59 for blood chemistry, blood biometry, and gene expression analysis in leukocyte through microarray assays. Immunoglobulins were quantified by enzyme-linked immunosorbent assay. The animals treated with the polyherbal mixture showed a quadratic effect on final body weight, daily weight gain, final hip height, and final thoracic girth. The best performance results were obtained with a treatment dose of 4 g/d. The serum IgG increased linearly with the treatment doses. Gene set enrichment analysis of upregulated genes revealed that the three biological processes with higher fold change were tight junction, mucin type O-Glycan biosynthesis, and intestinal immune network for IgA production. Also, these upregulated genes influenced arachidonic acid metabolism, and pantothenate and CoA biosynthesis. Gene ontology enrichment analysis indicated that the pathways enriched were PELP1 estrogen receptor interacting protein pathways, nuclear receptors in lipid metabolism and toxicity, tight junction, ECM-receptor interaction, thyroid hormone signaling pathways, vascular smooth muscle contraction, ribosome function, glutamatergic synapse pathway, focal adhesion, Hippo, calcium, and MAPK signaling pathways.

Effect of palmitic acid on the mitigation of milk fat depression syndrome caused by trans-10, cis-12-conjugated linoleic acid in grazing dairy cows.

The objective of the study was to evaluate the effect of adding protected palmitic acid (PA) to the ration of grazing dairy cows supplemented with protected conjugated linoleic acid (CLA) on milk production, chemical composition and fat profile. Six cows were used, 3/4 American Swiss × Zebu, under a rotational grazing system in a mixed sward with Cynodon plectostachyus, Brachiaria decumbens and Brachiaria brizantha. Furthermore, each cow received daily 4 kg concentrates and 8 kg sorghum silage, which made up the basal diet. The cows were distributed into three two-cow groups. Three treatments were randomly assigned to the groups, using a cross design: (1) control (basal diet), (2) basal diet + CLA (50 g/d) and (3) basal diet + CLA (50 g/d) + PA (412 g/d). The following variables were evaluated: forage intake, milk production, protein, fat and lactose concentration in milk, and milk fatty acid (FA) profile. There were no differences in forage intake between treatments; however, there were differences in milk production, protein, fat and lactose yield and fat concentration, which increased significantly in group CLA + PA when compared with group CLA. The concentration of FA synthesised de novo was lower when PA was included in the diet. Adding PA to the diet of grazing cows mitigates the milk fat decline caused by including trans-10, cis-12 CLA in the diet.

Nutraceutic effect of free condensed tannins of Lysiloma acapulcensis (Kunth) benth on parasite infection and performance of Pelibuey sheep.

Forty-five Pelibuey sheep were experimentally infested with nematodes to evaluate the effect of three free condensed tannin (FCT) levels of Lysiloma acapulcensis on fecal egg counts (FECs), packed cell volumes (PCV), ocular mucosa colors (OMC), average daily gain (ADG), and adult nematode count. Five treatments were used: 12.5, 25.0, and 37.5 mg of FCT kg-1 of body weight (BW); sterile water (control); and ivermectine (0.22 mg kg-1 of BW) as chemical group. The data were processed through repeated measurement analysis. Even though the three FCT doses decreased (P < 0.05) the FEC, the highest reduction was obtained with 37.5 mg kg-1 of BW. No differences were observed in PCV and OMC. Higher ADG (P < 0.05) was observed with 37.5 mg kg-1 of BW of FCT. The count of adult nematodes (females and males) in the higher dose of FCT was similar to chemical treatment. Dose of 37.5 mg kg-1 of BW decreased the parasite infection and improved the lamb performance. Therefore, this dose could be used as a nutraceutic product in sheep production.

Genetic variability and structure of an isolated population of Ambystoma altamirani, a mole salamander that lives in the mountains of one of the largest urban areas in the world.

Amphibians are globally threatened by habitat loss and fragmentation; species within the order Ambystoma are not the exception, as there are 18 species of mole salamanders in México, of which 16 are endemic and all species are under some national or international status of protection. The mole salamander, Ambystoma altamirani is a microendemic species, which is distributed in central México, within the trans-Mexican volcanic belt, and is one of the most threatened species due to habitat destruction and the introduction of exotic species. Nine microsatellite markers were used to determine the genetic structure, genetic variability, effective population size, presence of bottlenecks and inbreeding coefficient of one population of A. altamirani to generate information which might help to protect and conserve this threatened species. We found two genetic subpopulations with significant level of genetic structure (FST = 0.005) and high levels of genetic variability (Ho = 0.883; He = 0.621); we also found a small population size (Ne = 8.8), the presence of historical (M = 0.486) and recent bottlenecks under IAM and TPM models, with a low, but significant coefficient of inbreeding (FIS = -0.451). This information will help us to raise conservation strategies of this microendemic mole salamander species.

Genetic structure and diversity in an isolated population of an endemic mole salamander (Ambystoma rivulare Taylor, 1940) of central Mexico.

Human activities are affecting the distribution of species worldwide by causing fragmentation and isolation of populations. Isolation and fragmentation lead to populations with lower genetic variability and an increased chance of inbreeding and genetic drift, which results in a loss of biological fitness over time. Studies of the genetic structure of small and isolated populations are critically important for management and conservation decisions. Ambystoma rivulare is a micro-endemic Mexican mole salamander from central Mexico. It is found in the most ecologically disturbed region in Mexico, the Trans-Mexican Volcanic Belt. The goal of this study of the population genetics of the micro-endemic mole salamander was to provide information to be used as a basis for future research and conservation planning of this species and other species of the Ambystoma genus in Mexico. The structural analysis found two subpopulations, one for each river sampled, with no signs of admixture and very high levels of genetic differentiation. Medium to high levels of heterozygosity and few alleles and genotypes were observed. Evidence of an ancestral genetic bottleneck, low values of effective population size, small inbreeding coefficients, and low gene flow were also found.

Genetic diversity and genetic structure of an endemic Mexican Dusky Rattlesnake (Crotalus triseriatus) in a highly modified agricultural landscape: implications for conservation.

It is necessary to determine genetic diversity of fragmented populations in highly modified landscapes to understand how populations respond to land-use change. This information will help guide future conservation and management strategies. We conducted a population genetic study on an endemic Mexican Dusky Rattlesnake (Crotalus triseriatus) in a highly modified landscape near the Toluca metropolitan area, in order to provide crucial information for the conservation of this species. There was medium levels of genetic diversity, with a few alleles and genotypes. We identified three genetically differentiated clusters, likely as a result of different habitat cover type. We also found evidence of an ancestral genetic bottleneck and medium values of effective population size. Inbreeding coefficients were low and there was a moderate gene flow. Our results can be used as a basis for future research and C. triseriatus conservation efforts, particularly considering that the Trans-Mexican Volcanic Belt is heavily impacted by destructive land-use practices.

Prevalence and risk factors associated with Toxocara canis infection in children.

The objective of this study was to determine seroprevalence and identify risk factors associated with Toxocara canis infection. A clinical and epidemiological questionnaire and body mass index were used to assess the risk factors associated with human toxocariasis in 108 children with an age range of 2-16 years. Antibodies against Toxocara canis were detected using an ELISA test kit. Chi-square analysis and odds ratio (OR) were used to identify risk factors associated with Toxocara canis seropositivity. The prevalence of antibodies against Toxocara canis was greater (P = 0.02) in males than females (28.84% and 16.07%, resp.). Chi-square analysis and odds ratio revealed just one variable with P < 0.05, and OR > 1.0 was associated with seropositivity: the possession of dogs under one year old (OR = 1.78). Although not significant, the OR values suggest that other factors may be epidemiologically important for Toxocara presence such as not washing hands before meals, malnutrition, obesity, and use of public parks. Children in the age group >12 and <16 years old had higher seroprevalence to Toxocara canis (17.59%) than the >2 and <11 years old age group (4.62%). Toxocariosis infection needs to be prevented by pet deworming and hygienic measures after contact with dogs.

Spatial and temporal distribution of tuberculosis in the State of Mexico, Mexico.

Tuberculosis (TB) is one of the oldest human diseases that still affects large population groups. According to the World Health Organization (WHO), there were approximately 9.4 million new cases worldwide in the year 2010. In Mexico, there were 18,848 new cases of TB of all clinical variants in 2010. The identification of clusters in space-time is of great interest in epidemiological studies. The objective of this research was to identify the spatial and temporal distribution of TB during the period 2006-2010 in the State of Mexico, using geographic information system (GIS) and SCAN statistics program. Nine significant clusters (P < 0.05) were identified using spatial and space-time analysis. The conclusion is that TB in the State of Mexico is not randomly distributed but is concentrated in areas close to Mexico City.

Effect of ruminally protected methionine on body weight gain and growth of antlers in red deer (Cervus elaphus) in the humid tropics.

Sixteen male red deer (Cervus elaphus), with an initial weight of 93.83 ± 4.38 kg were used to study the effect of the dietary level of ruminally protected methionine (RPM) on growth, antler morphometry and serum metabolites. The deer were allowed to graze and were individually supplemented with concentrate to provide 0, 2.5, 3.5 or 4.5 g/day of RPM for 65 days. There was a quadratic effect on daily weight gain (0.163, 0.098, 0.147 and 0.172 kg/day; P < 0.005) and antler beam length (59.7, 63.6, 63.0 and 57.2 cm; P < 0.02) for RPM levels of 0 to 4.5 g/day, respectively. The brow tine length and the number of points were similar across all treatments. Serum glutamic pyruvate transaminase (SGPT) was reduced (quadratic effect; P < 0.02; 22.0, 29.6, 18.0 and 17.8 IU/l) to RPM levels of 0 to 4.5 g/day, respectively, whereas other metabolites (glucose, cholesterol, urea, creatinine, total protein and serum glutamic oxaloacetic transaminase [SGOT]) were unchanged. Increasing the RPM dose did not affect weight gain or antler growth. Methionine supplementation reduced the activity of SGPT.