Effect of limestone particle size and microbial phytase on phosphorus and calcium digestion kinetics along the gastrointestinal tract in laying hens.

1. This study assessed the effect of limestone particle size and microbial phytase incorporation on the fate of phosphorus (P) and calcium (Ca) along the gastrointestinal tract in 72 laying hens.2. Four experimental diets were formulated according to a 2 × 2 factorial arrangement to evaluate the effect of two coarse limestone (CL) inclusion. This included a mix (MIX) of 75% CL (2 - 4 mm) and 25% fine particles (FL, <0.5 mm) or 100% FL, in two different basal diets formulated without (MIX0 and FL0) or with 300 FTU of microbial phytase/kg (MIX300 and FL300).3. Contents of the crop, gizzard, duodenum, jejunum and ileum were collected to determine the mean retention time (MRT) of dry matter (DM), the recovery rate of Ca and P in each segment of the gastrointestinal tract and the apparent fractional digestibility coefficient (AD) of Ca and P in each intestinal segment.4. In hens fed FL, microbial phytase decreased the MRT of DM along the intestine (p < 0.05). In the crop and the gizzard, Ca recovery increased with MIX incorporation to a greater extent in hens fed without microbial phytase (p < 0.05). The mixed particle size incorporation decreased absorption kinetics of Ca in hens fed microbial phytase. The AD of P and the absorption kinetics of P were significantly decreased in hens receiving FL300, probably due to complex formation between Ca and phytic acid.5. This study showed that coarse limestone particles incorporation improved mineral utilisation along the digestive tract.

A physiologically based pharmacokinetic model for chickens exposed to feed supplemented with monensin during their lifetime.

We developed a flow-limited physiologically based pharmacokinetic model for residues of monensin in chickens and evaluated its predictive ability by comparing it with an external data set describing concentration decays after the end of treatment. One advantage of this model is that the values for most parameters (34 of 38) were taken directly from the literature or from field data (for growth and feed intake). Our model included growth (changes in body weight) to describe exposure throughout the life of the chicken. We carried out a local sensitivity analysis to evaluate the relative importance of model parameters on model outputs and revealed the predominant influence of 19 parameters (including three estimated ones): seven pharmacokinetic parameters, five physiological parameters and seven animal performance parameters. Our model estimated the relative bioavailability of monensin as feed additive at 3.9%, which is even lower than the absolute bioavailability in solution (29.91%). Our model can be used for extrapolations of farming conditions, such as monensin supplementation or building lighting programme (which may have a significant impact for short half-life molecules such as monensin). This validated PBPK model may also be useful for interspecies extrapolations or withdrawal period calculations for modified dosage regimens.

Buccal micronucleus cytome assay of populations under chronic heavy metal and other metal exposure along the Santiago River, Mexico.

The Santiago River is one of the most contaminated rivers in Mexico, with heavy metal levels above the allowed limits. Scientific evidence indicates that chronic heavy metal exposure leads to cytogenotoxic effects. The aims of this study were to evaluate the genotoxic and cytotoxic effects of such exposure in buccal mucosa cells by micronucleus (MN) assay and to identify other nuclear abnormalities (NAs), such as nuclear buds (NBUDs), binucleated cells (BNs), pyknotic nuclei (PNs), karyorrhexis (KX), karyolysis (KL), and abnormally condensed chromatin (CC). Assays were performed on samples from four populations located alongside the Santiago River that are under chronic exposure to heavy metals and other metals (HMMs), and the results were compared with those of a population without exposure to HMMs. The exposed group showed increased frequencies of NAs (KX, CC, and KL), which are associated with cytotoxic damage, and NBUDs, which are associated with genotoxic damage. Increased frequencies of NBUDs and CC were observed in subjects from El Salto/Juanacatlán, Ocotlán, and Paso de Guadalupe, and an increase in KX frequency was observed in subjects from El Salto/Juanacatlán. Significant differences in KL frequency were observed in subjects from La Barca, El Salto/Juanacatlán, Paso de Guadalupe, and Ocotlán. Predictors for increased development of MNs and NBUDs were high concentrations of Al, Zn, and Cu. In conclusion, chronic exposure to HMMs, especially Al, Cu, and Zn, in the studied population could be related to increased frequencies of NAs, such as NBUDs, KX, CC, and KL, in the buccal mucosa cells.

Increased micronuclei and nuclear abnormalities in buccal mucosa and oxidative damage in saliva from patients with chronic and aggressive periodontal diseases.

BACKGROUND AND OBJECTIVE: Periodontal disease is a chronic bacterial infection characterized by connective tissue breakdown and alveolar bone destruction because of inflammatory and immune response caused by periodontopathogens and long-term release of reactive oxygen species. A high number of reactive oxygen species result in periodontal tissue damage through multiple mechanisms such as lipid peroxidation, protein denaturation and DNA damage. The aim of this study was to evaluate DNA and oxidative damage in subjects with chronic or aggressive periodontitis and healthy controls. MATERIAL AND METHODS: Buccal mucosa cells and whole saliva were collected from 160 subjects, who were divided into three groups: subjects with chronic periodontitis (CP) (n = 58), subjects with aggressive periodontitis (AgP) (n = 42) and a control group (n = 60). DNA damage was determined by counting micronuclei (MN) and nuclear abnormalities (NAs) in exfoliated cells, including binucleated cells, cells with nuclear buds and karyolitic, karyorrhectic, condensed chromatin and pyknotic cells. The degree of oxidative stress was determined by quantifying 8-hydroxy-2'-deoxyguanosine (8-OHdG) in whole saliva. RESULTS: Subjects with CP or AgP presented significantly more ( p < 0.05) MN and NAs and higher levels of 8-OHdG ( p < 0.05) compared with the control group. CONCLUSION: Our results indicate that subjects with periodontitis (CP or AgP) exhibited an increase in the frequency of MN, NAs and 8-OHdG, which is directly related to DNA damage. In addition, a positive correlation exists between oxidative stress produced by periodontitis disease and MN.

Cross relationships between growth performance, growth composition and feed composition in broiler chickens, calculated from published data.

The study presented here used experimental data obtained from 42 articles to calculate the cross relationships between daily feed intake (DFI), feed composition (AMEn and CP), BW, daily weight gain (DG), mean age (A), and composition (FCG and PCG; fat and protein, respectively) of growth in broilers. All of the experiments selected were conducted at standard temperature and with ad libitum feeding. The articles in this database were published from 1980 to 2015, and represented a total of 12,277 broilers, 57 trials, and 384 basic treatments. Data ranged from 3 to 66, 0.077 to 3.322, 7.10 to 15.37, and 7.3 to 35.0 for A (d), mean BW (kg), AMEn (MJ/kg) and CP (%), respectively. Equations were established from regression calculations to calculate daily heat production as a function of BW, daily AME intake (MEI) as a function of BW, DG, FCG and PCG, PCG as a function of A and FCG, and FCG as a function of BW, protein efficiency (PE), AMEn, and CP. The combination of these equations expressing MEI, PCG, or FCG with equations expressing the definitions of PE, AME (from AMEn), and DFI (from MEI) constituted a system of 6 equations which could be used to determine DFI values from the values of AMEn, CP, A, BW, and DG. Using the values of AMEn, CP, A, BW, and DG from the database, the DFI values calculated with this system of equations showed a reasonable correlation with the DFI values measured (R2=0.880). This system of 6 equations yielded values for DFI, PE, PCG, and FCG that were in agreement with the classical effects produced by increased CP values, or by reduced fat deposition associated with genetic selection for leanness. This system of 6 equations might thus be considered an interesting framework for future nutritional modelling systems. Regressions predicting feed efficiency as a function of AMEn, CP, DG, and BW, or as a function of AMEn, FCG, DG, and BW showed R2 values of 0.767 and 0.747, respectively.

Association of SOD1 gene variants (50 bp Ins/Del, rs4817415, rs2070424, rs1041740, rs17880135) with plasma protein levels in vitiligo patients and their analysis in silico.

OBJECTIVE: Vitiligo is a common systemic, idiopathic autoimmune disease. The aim of this study was to analyze the frequency of variants of the superoxide dismutase 1 (SOD1) gene (50 bp Ins/Del, rs4817415, rs2070424, rs1041740, rs17880135) and circulating plasma protein levels through in-silico analysis. PATIENTS AND METHODS: Blood samples were collected from adult patients of both sexes with a clinical diagnosis of vitiligo. ELISA tests for SOD and analysis of gene variants by qPCR were compared to a disease-free reference group. RESULTS: The population analyzed was young people between 29 and 37 years old, with a higher percentage of women. The population was found in the Hardy-Weinberg equilibrium (HWE). The 50 bp Ins/Del, rs4817415, and rs2070424 variants showed no significant difference between groups (p > 0.05). Although, in the dominant model, the CT and CTTT genotypes of the rs1041740 and rs17880135 variants showed an association with susceptibility to vitiligo compared to the control. Plasma SOD levels showed significant differences between the groups, and when stratified according to the genotypes of each variant, there was a significant difference, except with the rs17880135 variant. The haplotypes InsCGTC and InsAGCC are shown to be risk factors for susceptibility to vitiligo. The in-silico analysis demonstrated that the rs4817415, rs2070424, rs1041740, and rs17880135 variants of the SOD1 gene participate in the modification of selected regulatory elements for differentiating the protein, transcription factors, and long non-coding RNA. CONCLUSIONS: Information regarding the pathogenesis of vitiligo helps recognize risk factors and identify the relationship of diagnostic markers of cell damage inherent to the disease. This will help improve aspects of prevention and the choice of treatment alternatives appropriate to each case.

Variants rs2758346, rs5746094, and rs2758331 of SOD2 gene: association study with breast cancer in a Mexican population and their analysis in silico.

OBJECTIVE: The aim of the study was to analyze the association between the superoxide dismutase 2 (SOD2) gene variants rs2758346, rs5746094, and rs2758331 and breast cancer (BC) in the Mexican population as well as to perform in silico assessments of the variants' potential impact. PATIENTS AND METHODS: We performed in silico analysis and analyzed 489 healthy women and 467 BC patients using TaqMan assays and Real-Time PCR. RESULTS: The TT genotype, the T allele of the rs2758346 variant, and the CC genotype of both rs5746094 and rs2758331 were identified as BC risk factors (p < 0.05). The TT and CTTT genotype of the rs2758346 variant stratified by the presence of ki-67 (> 20%), TCCC, and estrogen receptor (ER)-positive of the rs5746094 variant, and the CC and CT genotypes of rs2758331 stratified by menopause status and non-chemotherapy response were risk factors. The TTC and TTA haplotypes are risk factors for BC. In silico analysis revealed that the rs2758346, rs5746094, and rs2758331 variants could influence SOD2 gene regulation by transcription factors and circulating RNAs (circRNAs). CONCLUSIONS: The rs2758346, rs5746094, and rs2758331 variants of the SOD2 gene were associated with BC risk and could influence SOD2 regulation by transcription factors and circRNAs.

Effect of phytase and limestone particle size on mineral digestibility, performance, eggshell quality, and bone mineralization in laying hens.

The effect of microbial phytase and limestone particle size (LmPS) was assessed in Lohmann Tradition laying hens from 31 to 35 wk of age. Seventy-two hens were used in a completely randomized trial according to a 2 × 2 factorial arrangement with 2 levels of phytase/basal available P (aP); 0 FTU/kg with 0.30% aP or 300 FTU/kg with 0.15% aP, and 2 limestone particle sizes; fine particles (FL, <0.5 mm) or a mix (MIX) of 75% coarse limestone (CL, 2-4 mm) and 25% FL. Diets contained equivalent levels of Ca (3.5%), phytic P (PP; 0.18%), and aP (0.30%) considering the P equivalency of phytase. Thus, dietary treatments were FL0 and MIX0 without phytase, and FL300 and MIX300 with 300 FTU/kg phytase. Performance were recorded daily and eggshell quality (eggshell weight proportion, weight, thickness, and breaking strength) was measured weekly. At the end of the trial, bone parameters (tibia breaking strength, elasticity, and ash) and the apparent precaecal digestibility (APCD) of P and Ca were determined. No differences were observed between treatments in feed intake, FCR and bone parameters. Addition of MIX increased the eggshell proportion, weight and thickness in groups receiving no phytase (+6.5, +6.9, and +4.5%, respectively) while no effect was observed in groups receiving phytase (Phytase × LmPS, P < 0.05). In hens receiving FL, the APCD of P was lower in diets supplemented with phytase (-14 percentage points; Phytase × LmPS, P < 0.001). A higher phytate disappearance was observed in hens fed diets with phytase in combination with MIX (Phytase × LmPS, P = 0.005). Phytase and MIX together increased the APCD of Ca by 7.3 percentage points (Phytase × LmPS, P < 0.001). In conclusion, addition of CL could limit the formation of Ca-phytate complex thus improving the response of the birds to phytase compared to FL.

SOD1 gene variants rs4817415, rs2070424, and rs1041740 and their association with breast cancer risk.

OBJECTIVE: The aim of this investigation was to determine the frequency and association of the variants rs4817415, rs2070424, and rs1041740 of the SOD1 gene in healthy women and breast cancer (BC) patients. PATIENTS AND METHODS: Genomic DNA samples from 146 healthy women and 130 patients with BC were analyzed. RESULTS: GG genotype (OR 2.54, 95% CI 1.31-4.91, p = 0.0073) and the G allele (OR 1.37, 95% CI 1.09-1.73, p = 0.007) of the rs2070424 variant and CC genotype (OR 1.67, 95% CI 1.04-0.2.70, p = 0.0444) and allele C (OR 1.58, 95% CI 1.09-2.29, p = 0.0183) of the rs1041740 variant of SOD1 gene were associated as risk factors for BC susceptibility relative to the control group. Study groups comparison of the stratification by menopausal status showed an association of susceptibility to BC risk with carriers of the GG genotype (OR 2.9, 95% CI 1.11-7.81, p = 0.042) of the rs2070424 variant and with the premenopausal status of the study group and the TT (OR 2.89, 95% CI 1.73-4.85, p = 0.001) genotype of the rs1041740 variant. Furthermore, differences were observed in the patients with BC who were carriers of the CC genotype of the rs4817415 variant with elevated Ki-67 (≥ 20%) and who presented lymph node metastasis and stage III-IV BC (p<0.05). Two common haplotypes were identified in the study groups: CAC (protective factor), and CGC (risk factor) (p<0.05). CONCLUSIONS: The rs2070424 and rs1041740 variants of the SOD1 gene and the CGC haplotype were associated as risk susceptibility factors of BC in this sample analyzed.

Mutational spectrum of the iduronate-2-sulfatase gene in Mexican patients with Hunter syndrome.

OBJECTIVE: Hunter syndrome, or mucopolysaccharidosis type II (MPS II), is caused by deficiency of the lysosomal enzyme iduronate-2-sulfatase (IDS), which is responsible for degrading heparan and dermatan sulfate. The IDS gene is located on chromosome Xq28; pathological variants in this gene mostly consist of missense mutations and small and larger deletions, which produce different phenotypes. However, there is only one record in our population concerning the molecular mechanism of this disease; a genotype-phenotype description is not available. PATIENTS AND METHODS: There were included 24 unrelated male patients; clinical features were recorded at a database, fluorometric IDS enzyme activity testing was done for each individual, followed by Sanger sequencing to identify mutations. RESULTS: The mutational spectrum was found in 16 out of 24 Mexican patients with MPS II, and its range of phenotypes was described. The most frequent variants were of the missense type. The most affected exons were exon 3 (c.275T>G, c.284_287del, c.325T>C), exon 8 (c.1035G>C, c.550G>A), exon 9 (c.1403G>C, c.1229_1229del), and exon 7 (c.979A>C; this variant has not been previously reported). Exon 5 (c.438C>T, a non-pathogenic variant) was the least frequent. It was also found that the most severely affected patients were those with large deletions (2 out of 24) [rsaIDS: IDSP1 (P164)x0, FMR1, AFF2 (P164)x2] involving genes and pseudogenes. We found 2 patients with a synonymous mutation in exon 4. CONCLUSIONS: Our results confirmed reports in the literature, since the most frequent variants were reported in exons 3 and 8. However, this result varies from one previous report in our population, which mentions large deletions and rearrangements as the most frequent alterations, since complex rearrangements were not found. According to what has been previously found, the most severely affected patients are those in which a whole gene has been deleted.

Reducing environmental impacts of feed using multiobjective formulation: What benefits at the farm gate for pig and broiler production?

Feed production is the main contributor to several environmental impacts of livestock. To decrease environmental impacts of feed, those of feedstuffs should be considered during formulation. In particular, multiobjective feed formulation (MOF) can help reduce several environmental impacts simultaneously while keeping any increase in feed price moderate. The objective of this study was to assess environmental benefits of MOF at the farm gate for fattening pigs and broilers. For pigs, three feeding strategies were tested: classic 2-phase (2P), 2-phase with lower net energy content (2P-), and multiphase (MP). For broilers, two strategies were tested: classic 3-phase (3P) and 3-phase with higher digestible amino acid contents and lower metabolisable energy content (3P+). Diets were formulated using both least-cost formulation (LCF) and MOF, yielding six pig scenarios and four broiler scenarios. Environmental impacts at the farm gate were estimated using a modelling approach based on life cycle assessment. Indicators for six impact categories were then calculated: climate change (CC), cumulative non-renewable energy demand (CEDNR), acidification (AC), eutrophication (EU), land occupation (LO), and phosphorus demand (PD). As expected, MOF had lower farm-gate impacts than LCF (as much as -13%), but the degree of decrease varied by feeding strategy and impact. For pigs, MOF was equally effective in all strategies at reducing PD (-6 to -9%) and AC (-2%). In contrast, MOF was more effective in 2P and 2P- at decreasing CC (-5% to -7%), LO (-9% to -13%) and EU (-6% to -8%) than in MP (CC: -2%; LO: -4%; EU: -3%). The benefit of MOF was found greater in 2P (-7%) than in other pig strategies for CEDNR (-3 to +0%). For broilers, MOF was equally effective in both strategies tested at decreasing PD (-12%), AC (-2%), and EU (-4%). For CC and CEDNR, MOF was more effective in 3P (CC: -9%; CEDNR: -11%) than 3P+ (-6% for both impacts), but not for LO (+3% in 3P vs -1% in 3P+). These differences were due mainly to differences in animal performance (especially feed conversion ratio) among the strategies tested. Finally, in all scenarios, gross margin at the farm gate decreased with MOF comparatively to LCF (pigs: -3% to -11%); broilers: -7% to -11%). These results demonstrate the importance of comprehensive economic and environmental optimisation of feeding strategies by simultaneously considering feed impacts, animal performance, and manure management. To do so, further research is therefore required to develop new modelling tools.

Association between rs61764370, rs9266, and rs140080026 polymorphisms of the KRAS gene and breast cancer risk in a Mexican population.

OBJECTIVE: Polymorphisms of the KRAS gene have been shown to be associated with cancer. However, their association with breast cancer (BC) has been inconsistent. The purpose of this study was to determine the frequency with which the rs61764370, rs9266, and rs140080026 polymorphisms of the KRAS gene are associated with BC in patients of the Mexican population. PATIENTS AND METHODS: The rs61764370 A>C or T>G and rs140080026 A>G polymorphisms were determined by Polymerase Chain Reaction (PCR), and the rs9266 A>G polymorphism was determined by DNA sequencing of healthy Mexican subjects and BC patients. RESULTS: We observed that 78% of BC patients are overweight and/or obese, 57% have metastatic lymph nodes, 64% have luminal A/B cancer subtypes, and 61% have stage III-IV cancer. The rs61764370 polymorphism was associated with BC susceptibility when the BC patients and the control group were compared for the AC genotype (p = 0.020), AC vs. AA genotypes (heterozygous model: p = 0.016), AC/CC genotype (dominant model: p = 0.002), and the C allele (p = 0.007). The AC/CC genotype (p = 0.018; rs61764370) and AG/GG genotype (p = 0.005; rs9266) were associated with age in BC patients ≥50 years old. The AC/CC (rs61764370) and AG/GG (rs9266) genotypes were classified by molecular subtype, TNM stage, miscarriage, lymph node metastasis, ductal type, and Ki-67. These classifications were also associated with BC patients, indicating that these factors may significantly contribute to BC risk. The AAA (OR 0.65, 95% CI 0.43-0.98, p = 0.039) and CAA (OR 3.25, 95% CI 1.13-9.36, p = 0.021) haplotypes were also associated with BC susceptibility. In addition, 94 polymorphisms were identified on the 3'UTR of the KRAS gene GRCh 38/hg3 (25,209,490-25,209,122) in BC (n = 112) and control (n = 113) samples. However, 92 of these polymorphisms have only expressed the major allele (wild-type allele). CONCLUSIONS: The rs61764370 polymorphism in the KRAS gene was associated with BC susceptibility in the Mexican population. The dominant model of the rs61764370 and rs9266 polymorphisms (classified by molecular subtype, miscarriage, TNM stage, lymph node metastasis, and Ki-67) could significantly contribute to BC risk in patients ≥50 years. The CAA haplotype could significantly contribute to BC risk in the Mexican population analyzed.

Short cold exposures during incubation and postnatal cold temperature affect performance, breast meat quality, and welfare parameters in broiler chickens.

Cold stimulations during egg incubation were reported to limit the occurrence of ascites in broilers subjected to cold temperature after 14 d of age. However, data are lacking on the impacts of such strategy in case of cold temperature conditions at start. This study aimed to evaluate the effects of incubation and posthatch cold challenge on performance, breast muscle integrity, and meat processing quality in broiler chickens. Ross 308 eggs were incubated under control temperature (I0, 37.6°C) or subjected to 15°C during 30 min on day 18 and 19 of incubation (I1). Chicks from each group were reared in floor pens either at standard rearing temperature (T0), from 32°C at 0 d to 21°C at 21 d of age, or exposed to colder rearing temperature (T1), from 29°C at 0 to 21°C at 21 d of age. All birds were then kept at 21°C until slaughter (day 40), when body weights (BW), feed conversion ratio (FCR), breast muscle yield, meat processing quality, and the occurrences of meat defects, hock burns, and pododermatitis were recorded. No significant impact of incubation conditions on hatchability was observed. At day 40, BW was more under T1 than under T0 conditions, with T0 females (but not males) presenting more BW after I1 than after I0 conditions. In the whole period, T1 chickens presented lower FCR than T0 chickens and higher breast meat yields at day 40. The occurrence of white striping was more in I1T1 males than in all other groups, except for the I0T1 males. Hock burns were more frequent in I1T1 males than in all females and I0T0 males, whereas the occurrence of pododermatitis was lower in T0 males than in other groups. Despite some positive effects of I1 incubation on growth after starting under low ambient temperature, this study reveals the limits of such strategy concerning chicken health and welfare, demonstrating that early thermal environment is a major component of the quality and sustainability of chicken meat production.

The rs1008562, rs2234671, and rs3138060 polymorphisms of the CXCR1 gene are associated with breast cancer risk in a Mexican population.

OBJECTIVE: The rs1008562, rs2234671 and rs3138060 polymorphisms of the CXCR1 gene have been shown to be associated with many diseases, but in breast cancer (BC) their association has not been detected. The purpose of this study was to determine the frequency and association of the rs1008562, rs2234671 and rs3138060 polymorphisms of CXCR1 gene in BC patients in the Mexican population. PATIENTS AND METHODS: The CXCR1 polymorphisms were determined by Polymerase Chain Reaction (PCR) and real time-PCR in healthy Mexican subjects and BC patients. RESULTS: The prevalent patron in BC patients was observed, the majority were overweight and obesity (72%) with metastatic lymph nodes (48%), luminal A/B subtypes (63%), and advanced stages (60%). Triple negative breast cancer (TNBC) patients: they were younger (58%) than 43 years old, overweight (33%), obesity (42%), ductal type histological (98%), metastasis to lymph nodes (47%), advanced stages III-IV (61%) and metastasis (33%). The rs2234671 polymorphism was associated with BC susceptibility when BC patients and the control group were compared for the CC genotype (p=0.037), CG (heterozygous model: p=0.018), GC/CC (dominant model: p=0.004), and the C allele (p=0.001), as well as the GC/CC genotype with hormone replace therapy (HRT, p=0.016). The rs3138060 polymorphism was associated with BC susceptibility for CG/GG genotype (dominant model: p=0.032) and G allele (p=0.018). Although the association between the dominant model of rs1008562, rs2234671, rs3138060 polymorphisms and BC patients and control was evident for tobacco and alcohol consumption (p<0.05). The rs1008562, rs2234671, and rs3138060 polymorphisms of the CXCR1 gene classified by molecular subtype and stage were also associated with BC patients, indicating that these factors may significantly contribute to BC risk. The CCC (OR 1.75, 95% CI 1.03- 2.97, p=0.046), GGG (OR 3.73, 95% CI 1.61- 8.65, p=0.0018) haplotypes were also associated with BC susceptibility. CONCLUSIONS: Rs2234671 and rs3138060 polymorphisms in the CXCR1 gene were associated with BC susceptibility in the Mexican population. The dominant model of the rs1008562, rs2234671 and rs3138060 polymorphisms could significantly contribute to BC risk in tobacco and alcohol consumption, molecular subtype and stage. The rs1008562, rs2234671 and rs3138060 polymorphisms, and the haplotypes CCC and GGG could significantly contribute to BC risk in the Mexican population analyzed.

Chromosome instability in a patient with recurrent abortions.

Chromosomal aberrations are one of the recognized possible etiologic genetic causes of recurrent spontaneous abortions. Increased chromosome instability without constitutional chromosome abnormalities is uncommon in these couples. In this work we present a non consanguineous healthy couple with recurrent abortions without constitutional chromosome aberrations in which spontaneous and induced chromosome aberrations were observed in the female. Chromosome analysis was performed in the presence of different chromosome damage inductors such as gamma radiation, Uv light, and mitomycin-C. Alterations observed only in the female were: spontaneous and induced tetraradial chromosomes and increased chromosomal damage induced only by gamma radiation. Oral mucosa micronuclei were moderately increased in the female. Chromosome instability associated to abortion is proposed.

Review: Associations among goods, impacts and ecosystem services provided by livestock farming.

Livestock is a major driver in most rural landscapes and economics, but it also polarises debate over its environmental impacts, animal welfare and human health. Conversely, the various services that livestock farming systems provide to society are often overlooked and have rarely been quantified. The aim of analysing bundles of services is to chart the coexistence and interactions between the various services and impacts provided by livestock farming, and to identify sets of ecosystem services (ES) that appear together repeatedly across sites and through time. We review three types of approaches that analyse associations among impacts and services from local to global scales: (i) detecting ES associations at system or landscape scale, (ii) identifying and mapping bundles of ES and impacts and (iii) exploring potential drivers using prospective scenarios. At a local scale, farming practices interact with landscape heterogeneity in a multi-scale process to shape grassland biodiversity and ES. Production and various ES provided by grasslands to farmers, such as soil fertility, biological regulations and erosion control, benefit to some extent from the functional diversity of grassland species, and length of pasture phase in the crop rotation. Mapping ES from the landscape up to the EU-wide scale reveals a frequent trade-off between livestock production on one side and regulating and cultural services on the other. Maps allow the identification of target areas with higher ecological value or greater sensitivity to risks. Using two key factors (livestock density and the proportion of permanent grassland within utilised agricultural area), we identified six types of European livestock production areas characterised by contrasted bundles of services and impacts. Livestock management also appeared to be a key driver of bundles of services in prospective scenarios. These scenarios simulate a breakaway from current production, legislation (e.g. the use of food waste to fatten pigs) and consumption trends (e.g. halving animal protein consumption across Europe). Overall, strategies that combine a reduction of inputs, of the use of crops from arable land to feed livestock, of food waste and of meat consumption deliver a more sustainable food future. Livestock as part of this sustainable future requires further enhancement, quantification and communication of the services provided by livestock farming to society, which calls for the following: (i) a better targeting of public support, (ii) more precise quantification of bundles of services and (iii) better information to consumers and assessment of their willingness to pay for these services.

Reducing the CP content in broiler feeds: impact on animal performance, meat quality and nitrogen utilization.

Reducing the dietary CP content is an efficient way to limit nitrogen excretion in broilers but, as reported in the literature, it often reduces performance, probably because of an inadequate provision in amino acids (AA). The aim of this study was to investigate the effect of decreasing the CP content in the diet on animal performance, meat quality and nitrogen utilization in growing-finishing broilers using an optimized dietary AA profile based on the ideal protein concept. Two experiments (1 and 2) were performed using 1-day-old PM3 Ross male broilers (1520 and 912 for experiments 1 and 2, respectively) using the minimum AA:Lys ratios proposed by Mack et al. with modifications for Thr and Arg. The digestible Thr (dThr): dLys ratio was increased from 63% to 68% and the dArg:dLys ratio was decreased from 112% to 108%. In experiment 1, the reduction of dietary CP from 19% to 15% (five treatments) did not alter feed intake or BW, but the feed conversion ratio was increased for the 16% and 15% CP diets (+2.4% and +3.6%, respectively), while in experiment 2 (three treatments: 19%, 17.5% and 16% CP) there was no effect of dietary CP on performance. In both experiments, dietary CP content did not affect breast meat yield. However, abdominal fat content (expressed as a percentage of BW) was increased by the decrease in CP content (up to +0.5 and +0.2 percentage point, in experiments 1 and 2, respectively). In experiment 2, meat quality traits responded to dietary CP content with a higher ultimate pH and lower lightness and drip loss values for the low CP diets. Nitrogen retention efficiency increased when reducing CP content in both experiments (+3.5 points/CP percentage point). The main consequence of this higher efficiency was a decrease in nitrogen excretion (-2.5 g N/kg BW gain) and volatilization (expressed as a percentage of excretion: -5 points/CP percentage point). In conclusion, this study demonstrates that with an adapted AA profile, it is possible to reduce dietary CP content to at least 17% in growing-finishing male broilers, without altering animal performance and meat quality. Such a feeding strategy could therefore help improving the sustainability of broiler production as it is an efficient way to reduce environmental burden associated with nitrogen excretion.

Effect of low incubation temperature and low ambient temperature until 21 days of age on performance and body temperature in fast-growing chickens.

Thermal manipulation during embryogenesis was previously reported to decrease the occurrence of ascites and to potentially improve cold tolerance of broilers. The objective of our study was to explore the effects of the interaction of cold incubation temperatures and cool ambient temperatures until 21 d of age on performance and body temperature. Ross 308 eggs were incubated either under control conditions I0 (37.6°C) or with cyclic cold stimulations I1 (6 h/d at 36.6°C from d 10 to 18 of incubation) or with 2 cold stimulations I2 (30 min at 15°C) at d 18 and 19 of incubation. These treatments were followed by individual rearing and postnatal exposure to either standard rearing temperature T0 (from 33°C at hatching to 21°C at d 21) or continuously lower temperature T2 (from 28°C at hatching to 21°C at d 21) or exposure to cyclically lower temperature T1 (with circadian temperature oscillations). Treatments I1 and I2 did not significantly alter hatchability compared to control incubation (with 94.8, 95.1, and 92.3%, respectively), or hatching BW and overall chick quality. Hatching body temperature (Tb) was 0.5 and 0.3°C higher in I1 than in I0 and I2 groups, respectively (P = 0.007). A doubled occurrence of health problems was observed with T2 condition, regardless of incubation or sex. At d 3, BW was 2% lower with treatment I1 than with I0 and I2 and was 3% higher in T1 and T2 groups than in T0, but these effects disappeared with age. Group T2 presented a 5% higher feed intake than the control group T0 between 3 and 21 d of age (P = 0.025). Feed conversion ratio (FCR) was affected by experimental conditions (P < 0.001), with low FCR values obtained with I2 incubation in control or cyclically cold postnatal conditions. Maximal FCR values were observed in the continuously cold postnatal conditions, in males submitted to control incubation and in females submitted to I1 incubation, revealing sex-dependent effects of the treatments on performance.

Oral sildenafil citrate lacks genotoxicity and cytotoxicity in a primate model: Callithrix jacchus.

OBJECTIVE: To determine sildenafil citrate (SC) genotoxicity and cytotoxicity in the Callithrix jacchus. STUDY DESIGN: Fifteen organisms were assigned to one of three groups as follows: experimental (25 mg/kg of SC); negative control (glucose solution 5%); and positive control (3 mg/kg of cytocine arabinoside). Systemic hemodynamic changes were monitored in each animal before and after each treatment. A drop of blood was obtained before and after the treatment at 24-120 h. Smears were made and the frequency of micronucleated erythrocytes (MNE), micronucleated polychromatic erythrocytes (MNPCE) and polychromatic erythrocytes (PCE) was counted. RESULTS: No significant differences in MNE, MNPCE and PCE were found in the group that received sildenafil and negative control. A significant increase in genotoxicity and cytotoxicity was observed in the positive control group. No changes were observed in systemic hemodynamic changes. CONCLUSION: The macro-dose of SC lacks genotoxic, cytotoxic or systemic hemodynamic changes effects in this species.

Manipulation of dietary methionine+cysteine and threonine in broilers significantly decreases environmental nitrogen excretion.

The intensification of livestock have increased the emission of pollutants to the environment, leading to a growing interest in seeking strategies that minimise these emissions. Studies have shown that it is possible to manipulate diets by reducing CP levels and thus reducing nitrogen (N) excretion, without compromising performance. However, there is no knowledge of any study that has focused on reducing N excretion and relating this reduction to individual amino acids. This study investigated the effect of dietary methionine+cysteine (MC) and threonine (THR), the two most limiting amino acids for broiler production, on nitrogen excretion (NE) and nitrogen deposition (ND) and determined the efficiency of utilisation of both amino acids for protein deposition. Six trials were conducted to measure the NE and ND in broiler chickens during three rearing phases in response to dietary amino acid. The efficiency of utilisation of the amino acids was calculated by linear regression of body protein deposition and the amino acid intake. Despite the differences between sexes and phases, the efficiency of utilisation was the same, being 0.60 and 0.59 for MC and THR, respectively. The rate of NE behaved exponentially, increasing with amino acid intake, and can exceed 50% of N intake, being higher than ND. On average, for a reduction in intake of each unit of MC or THR (mg) there is a reduction of 0.5% of NE. Although this reduction seems low, considering that it corresponds to changes in one amino acid only, the impact on a large scale would be significant. Knowledge of how animals respond to NE and ND/protein deposition according to amino acid dietary content may represent new efforts towards reducing the impact on environment.