RESUMO
Fluazuron is a novel veterinary pour-on antitick formulation which can be applied simultaneously with bovine reproduction management strategies. Considering the economic importance of the livestock industry in many countries, it is important to know whether antiparasitics such as fluazuron may cause embryonic loss. The aim of this study was to evaluate the toxicological effect of fluazuron on bovine oocytes during in vitro maturation. The best fluazuron concentrations were determined in a preliminary experiment on Chinese hamster ovary (CHO)-K1 cells and further used to compare fluazuron toxicity in both study models. Results of the annexin V and alkaline single cell gel electrophoresis assays demonstrated that fluazuron caused cytotoxicity and genotoxicity in bovine cumulus cells at all the concentrations tested (50, 75 and 100 µg fluazuron/mL). The evaluation of cortical granules and mitochondria distribution showed that cytoplasmic maturation was not affected by fluazuron treatment. However, a decrease in metaphase II + polar body, degenerate oocytes as well as disorganized chromatin in polar body were observed at all concentrations tested. Whereas the fertilization process was not altered by 50 µg/mL fluazuron, the embryo development rate decreased significantly. No significant differences were observed in any of the oxidative stress parameters assessed. This study contributes to a better understanding of fluazuron in bovines, suggesting that the antiparasitic may affect bovine reproduction and might cause embryo loss.
Assuntos
Técnicas de Maturação in Vitro de Oócitos , Oócitos , Compostos de Fenilureia , Animais , Bovinos , Oócitos/efeitos dos fármacos , Compostos de Fenilureia/farmacologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Técnicas de Maturação in Vitro de Oócitos/métodos , Células CHO , Cricetulus , Antiparasitários/farmacologia , Antiparasitários/toxicidade , FemininoRESUMO
Zinc (Zn) plays essential roles in numerous cellular processes. However, there is limited understanding of Zn homeostasis within the bovine reproductive system. This study investigated the influence of estradiol (E2) and progesterone (P4) on Zn transporter expression and intracellular free Zn levels in bovine oviduct epithelial cells (BOEC). For this purpose, cells were harvested from slaughtered cows and cultured in vitro. Intracellular Zn concentrations were measured using FluoZin-3AM staining, while real-time polymerase chain reaction assessed Zn transporter gene expression and quantification. Overall, our results confirmed the gene expression of all the evaluated Zn transporters (ZIP6, ZIP8, ZIP14, ZnT3, ZnT7 and ZnT9), denoted and the active role of E2 and P4 in intracellular Zn regulation. Our findings suggest an interaction between Zn, E2 and P4.
Assuntos
Proteínas de Transporte , Progesterona , Zinco , Feminino , Bovinos , Animais , Progesterona/farmacologia , Progesterona/metabolismo , Zinco/farmacologia , Zinco/metabolismo , Oviductos/metabolismo , Células Epiteliais/metabolismo , Estrogênios/farmacologiaRESUMO
Follicular wave synchronization (FWS) before ovum pick-up (OPU) is one of the strategies used to improve the efficiency of in vitro embryo production (IVP). This study aimed to evaluate the effect of FWS on the total follicular number, cumulus-oocyte complex (COC) recovery, and in vitro embryo development in Angus cows (n = 33) subjected to OPU with 14-day intersession intervals. Additionally, it was also evaluated the presence of carryover effects given the short intersession interval used. The experiment was run as a 2-treatment (FWS vs. Control) x 2-period (1 vs. 2) crossover design. Animals in the FWS group received an intravaginal progesterone implant (1gr), estradiol benzoate (2 mg), and D-cloprostenol (150 µg) on day 0 and the OPU was performed on day 5. Control group animals did not receive any hormone treatment. The FWS increased the number of 6-10 mm follicles (P = 0.05), but it decreased the COC recovery rate (P < 0.01). The FWS did not affect the total or frozen embryo numbers (P = 0.49 and P = 0.17; respectively), but it increased the total blastocyst cell number (P < 0.01). A carryover effect was found on the total and < 6 mm follicles number (P = 0.10 and P < 0.01; respectively), and on the regular, atretic, viable, and total number of COC (P = 0.01, P = 0.08, P = 0.02 and P < 0.01; respectively). We concluded that the FWS increased the quality of embryos after OPU with 14-day intersession intervals in Angus cows and that this kind of OPU/IVP scheme enabled the existence of a carryover effect, especially on the follicle number and COC morphology.
Assuntos
Recuperação de Oócitos , Progesterona , Feminino , Bovinos , Animais , Progesterona/farmacologia , Recuperação de Oócitos/veterinária , Recuperação de Oócitos/métodos , Fertilização in vitro/veterinária , Fertilização in vitro/métodos , Folículo Ovariano , Oócitos , ÓvuloRESUMO
The aim of this experiment was to evaluate the effect of increasing dietary omega-3 (n-3) polyunsaturated fatty acid (PUFA) supplementation on plasma and follicular fluid resolvin D1 (RvD1) concentration and the mRNA expression of genes related to RvD1 production, inflammatory response, oxidative stress, hormone receptors and production, and free fatty acid receptors in the granulosa cells of ewes. Dorsetâ ×â Hampshire ewes (nâ =â 24) aged 2 to 4 yr and with an initial body weight (BW) of 84.08â ±â 13.18 kg were blocked by body condition score (BCS) and BW, and randomly assigned to 12 pens. Each pen within each block was randomly assigned to one of three treatments: 1) diet without fatty acid supplementation (control), 2) diet with 0.5% n-3 PUFA supplementation (PUFA0.5), and 3) diet with 1% n-3 PUFA supplementation (PUFA1). BW, BCS, and blood samples were obtained on day 1 and every 21 d for 3 mo. Ewes were then synchronized, superstimulated, and ovariectomized. Antral follicles were aspirated to evaluate RvD1 concentration in follicular fluid, and granulosa cells were used to determine mRNA abundance. Data were analyzed as a randomized complete block design using a mixed model (MIXED or GLIMMIX with log as a link function when data presented a nonnormal distribution). A polynomial effect of treatments was used to analyze RvD1 concentration and mRNA expression when there was no interaction. In addition, the correlation between plasma and follicular fluid RvD1 concentration was evaluated. We found no differences in BW (Pâ =â 0.28) and BCS (Pâ =â 0.29) between treatments. The concentration of RvD1 in plasma and follicular fluid linearly increased (Pâ =â 0.03) and tended to increase (Pâ =â 0.06) concomitantly to increasing PUFA supplementation. Plasma and follicular fluid RvD1 concentrations were positively correlated (râ =â 0.61; Pâ <â 0.01). The abundance of GPX1 and GPR32 mRNA tended to increase linearly with increasing PUFA supplementation (Pâ =â 0.06). In addition, PUFA supplementation linearly decreased and tended to decrease IL-1ß and COX-2 mRNA abundance (Pâ =â 0.01 and Pâ =â 0.06, respectively). In conclusion, the correlation between plasma and follicular fluid RvD1 concentration indicates a relationship between both compartments. Also, the decrease of IL-1ß and the increase of GPX1 mRNA abundance after PUFA supplementation could have beneficial effects on follicle development.
The aim of this experiment was to evaluate the effects of increasing dietary omega-3 (n-3) polyunsaturated fatty acid (PUFA) supplementation on plasma and follicular fluid resolvin D1 (RvD1) concentration, and the mRNA expression of genes related to RvD1 synthesis, inflammatory response, oxidative stress, reproductive hormone receptors and production, and free fatty acid receptors in ewes. Twenty-four ewes aged 2 to 4 yr were assigned to 12 pens and randomly allocated to one of three treatments: 1) diet without fatty acid supplementation (control), 2) diet with 0.5% n-3 PUFA (PUFA0.5), and 3) diet with 1% n-3 PUFA (PUFA1). Body weight (BW), body condition score (BCS), and blood samples were obtained on day 1 and every 21 d for 3 mo. Ewes were then synchronized, superstimulated, and ovariectomized. Antral follicles were aspirated to evaluate follicular fluid RvD1 concentration, and granulosa cells were used to analyze mRNA concentration. We found no differences in BW and BCS between treatments. Plasma and follicular fluid RvD1 concentration increased concomitantly to increasing dietary PUFA supplementation. There was a positive correlation between plasma and follicular fluid RvD1 concentrations. Omega-3 PUFA increased the mRNA abundance of genes associated with RvD1 synthesis and oxidative damage response. In addition, PUFA supplementation linearly decreased the mRNA abundance of genes associated with inflammatory response. In conclusion, the positive correlation between plasma and follicular fluid RvD1 concentrations demonstrates a relationship between both compartments. Also, changes in gene expression after PUFA supplementation may have a beneficial effect on the follicle and, in turn, on reproduction.
Assuntos
Suplementos Nutricionais , Ácidos Graxos Ômega-3 , Animais , Ovinos , Feminino , Líquido Folicular/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Graxos/farmacologia , Células da Granulosa/metabolismoRESUMO
In brief: The bovine high fecundity allele, Trio, results in the occurrence of multiple ovulations and is characterized by antral follicles that develop slower and acquire ovulatory capacity at smaller sizes. This study provides novel information on the effect of the Trio allele on early folliculogenesis. Abstract: The bovine high fecundity allele, Trio, causes overexpression in granulosa cells (GCs) of SMAD6, an inhibitor of BMP15-activated SMAD signalling. Furthermore, the Trio allele results in antral follicles that develop slower, acquire ovulatory capacity at smaller sizes, and have three-fold greater ovulation rate compared to half-sib non-carriers. The present study was designed to determine preantral follicle numbers and size in Trio carrier and non-carrier cattle testing the hypothesis that inhibition of SMAD signalling would alter preantral follicle activation and/or growth. Ovarian tissues from Trio carrier (n = 12) and non-carrier (n = 12) heifers were obtained by laparotomy after follicle wave synchronization. Follicle numbers and dimensions were determined for each stage of development (primordial, transitional, primary, and secondary) from paraffin-embedded sections. There were no differences in the number of primordial, transitional, or secondary follicles or in antral follicle count, circulating AMH, or ovarian volume between carriers and non-carriers. Trio carriers had ~2.5-fold greater (P < 0.01) number of primary follicles than non-carriers, and transitional and primary follicles were larger (~1.2-fold; P < 0.1) in Trio carriers. Oocyte volume of primordial and transitional follicles was not different between genotypes; however, oocytes were larger (P < 0.05) in primary (~1.3-fold) and secondary (~1.8-fold) follicles for Trio carriers. Granulosa cell numbers were not different (P > 0.3) between carriers and non-carriers, irrespective of the stage of development. These results suggest that, after primordial follicle activation, follicles in Trio carrier cattle have slower progression through the primary stage, hence the larger oocyte and greater number of primary follicles.
Assuntos
Células da Granulosa , Folículo Ovariano , Bovinos , Animais , Feminino , Alelos , Ovulação/genética , Oócitos , Fertilidade/genéticaRESUMO
Veterinary drugs are potential environmental pollutants that interfere with male reproductive function. Infertility has increased, and it is known that environmental toxins contribute to declining sperm parameters. Amitraz {N,N-[(methylamino) dimeth-ylidyne] di-2,4-xylidine} (AMZ) is a formamidine pesticide widely used as an insecticide and an acaricide. The aim of this study was to evaluate the toxicity of AMZ in bovine sperm. Three experiments using frozen-thawed bovine semen incubated with AMZ for 2 h were carried out. Negative and solvent (dimethyl sulfoxide) controls were run simultaneously with treatments. In experiment 1, the AMZ concentrations used were 10, 15 and 25 µg AMZ/ml and the sperm parameters evaluated were viability, mitochondrial activity, acrosomal status, functional membrane integrity and apoptosis. In experiments 2 and 3, 25 µg AMZ/ml was used to evaluate fertilizing capacity, embryo development and blastocyst DNA damage. In experiment 1, 25 µg AMZ/ml decreased sperm viability (P = 0.01), reduced mitochondrial activity (P = 0.03) and induced apoptosis (P < 0.01). Also, 15 and 25 µg AMZ/ml affected functional membrane integrity (P < 0.01). In experiment 2, AMZ did not alter sperm-zona binding (P = 0.40) and pronucleus formation (P = 0.36). In experiment 3, 25 µg AMZ/ml decreased the rate of embryo development (P < 0.01) and increased apoptosis (P = 0.03). These results suggest that AMZ induced alterations in bovine sperm, probably affecting male fertility at concentrations that could be present in the environment.
Assuntos
Análise do Sêmen , Preservação do Sêmen , Masculino , Animais , Bovinos , Análise do Sêmen/veterinária , Sêmen , Espermatozoides , Preservação do Sêmen/veterinária , Desenvolvimento Embrionário , Criopreservação/veterináriaRESUMO
In vitro embryo production has grown in recent decades due to its great potential for cattle production. However, the quality of in vitro-produced embryos is lower compared with those produced in vivo. The postfertilization culture environment has a major influence on bovine embryo quality. We hypothesize that the inclusion of the inclusion of alpha-lipoic acid (ALA) in the in vitro culture (IVC) medium during the first 24 h would have positive effects on embryo development in vitro and cryotolerance. The aims of this study were to evaluate the antioxidant effect of ALA in IVC medium for 24 h on bovine zygotes (21 h post in vitro fertilization, IVF), day 2 cleaved embryos (46 h post-IVF), and to assess embryo quality, developmental competence, and cryotolerance after vitrification. In all experiments, IVC medium was the Control, and 2.5 µM ALA was the treatment implemented. Viability and reactive oxygen species (ROS) levels in zygotes and day 2 embryos did not differ from the Control (P > 0.05). Supplementation with ALA increased total blastocyst and hatching rates (P < 0.05). It also improved embryo quality, evidenced by the increased blastocyst total cell number and the percentage of excellent-quality embryos observed (P < 0.05). In embryos cultured with ALA and then vitrified, ALA reduced intracellular ROS levels in warmed blastocysts (P < 0.05). In conclusion, ALA supplementation to IVC medium during 24 h is a new advantage in improving embryo quality for assisted bovine reproduction.
Assuntos
Criopreservação , Ácido Tióctico , Bovinos , Animais , Criopreservação/veterinária , Ácido Tióctico/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Técnicas de Cultura Embrionária/veterinária , Vitrificação , Fertilização in vitro/veterinária , Blastocisto , Desenvolvimento EmbrionárioRESUMO
The aim of this study was to evaluate the association between plasma copper (Cu) concentration and ovarian function during a fixed-time artificial insemination (FTAI) protocol and the effect of parenteral Cu administration (100 mg) at the start of such protocol (day 0) on area of preovulatory follicle (APF); area of corpus luteum (ACL), plasma estradiol (E2), and progesterone (P4) concentrations; CL blood flow (CLBF); and pregnancy rate in beef heifers and cows. In cows, plasma Cu concentration on days 0 and 7 correlated positively with APF. Copper administration increased plasma Cu concentration and decreased APF and plasma E2 concentration (day 9), without modifying ACL, plasma P4 concentration, and CLBF (day 16) in cows. Pregnancy rate was higher in Cu-supplemented cattle on day 41 after FTAI as compared with controls (58.76 and 45.28%, respectively). In conclusion, Cu administration at the beginning of the FTAI protocol increased pregnancy rate in beef heifers and cows, modifying APF and plasma E2 concentration in the latter.
Assuntos
Cobre , Sincronização do Estro , Animais , Bovinos , Cobre/farmacologia , Corpo Lúteo , Estradiol , Sincronização do Estro/métodos , Feminino , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Gravidez , Taxa de Gravidez , ProgesteronaRESUMO
Ghrelin is a gut hormone related to energy balance and reproductive functions. The aim of this study was to evaluate the effect of ghrelin antagonist D-Lys3-GHRP-6 (GA) as a potential agent that prevents ghrelin effects during bovine oocyte maturation on progesterone production, cumulus cell (CC) viability, CC DNA damage and embryo development and hatching rates. Ghrelin's potential to induce oxidative stress in cumulus-oocyte complexes (COC) was also evaluated. COCs were cultured for 24 hr in medium without supplementation (C) or supplemented with 60 pM ghrelin (Ghrelin60), Ghrelin60 + 20 pM GA (GA20), Ghrelin60 + 60 pM GA (GA60) or Ghrelin60 + 100 pM GA (GA100) for experiment I. For experiment II, C and Ghrelin60 treatments were used. Differences between C and Ghrelin60 and the linear or quadratic association between GAs on Ghrelin60 were evaluated. Results demonstrated that Ghrelin60 increased progesterone concentration, reduced CC viability, induced CC DNA damage and decreased blastocyst and hatching rate compared with C (p < .05). GA20, GA60 and GA100 had a linear effect on CC genetic damage index (p ≤ .05) and a quadratic effect on CC viability (p < .01). GA20 counteracted the low hatching rate produced by Ghrelin60. However, GAs did not counteract progesterone concentration and blastocyst rate (p ≥ .21). GRH60 did not differ from C in the oxidative status (p ≥ .19). Our study highlights that GA could prevent the negative effects of ghrelin during bovine IVM.
Assuntos
Células do Cúmulo/efeitos dos fármacos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oligopeptídeos/farmacologia , Oócitos/efeitos dos fármacos , Animais , Blastocisto/efeitos dos fármacos , Bovinos , Dano ao DNA , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Grelina/farmacologia , Técnicas de Maturação in Vitro de Oócitos/métodos , Estresse Oxidativo , Progesterona/metabolismoRESUMO
The aim of this study was to evaluate the genotoxic and cytotoxic effects of amitraz (AMZ) on the primary culture of bovine cumulus cells (CC) and oocyte nuclear maturation. Cytotoxicity was evaluated by assessing mitochondrial activity with the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Genotoxicity was estimated using the alkaline single cell gel electrophoresis (SCGE) assay. Apoptosis was detected with the Annexin V-affinity assay. The in vitro maturation test was performed in bovine oocytes. To understand AMZ action, glutathione content, superoxide dismutase enzyme activity, and lipid peroxidation were evaluated in CC. Results showed that AMZ lethal concentration (LC 5024h) for bovine CC was 32.55 µg/mL (MTT assay). A 25 µg/mL induced late apoptosis and necrotic cells (p < 0.05); however, DNA damage was decreased at the same concentration (SCGE assay; p < 0.05). A decrease in metaphase II was observed at 25 µg/mL, and degenerate oocytes were observed at 15 and 25 µg/mL (p < 0.05). None of the oxidative stress parameters evaluated showed significant differences. This study contributes to a better understanding of AMZ in this model, suggesting its potential cytotoxicity and impact on bovine reproduction.
Assuntos
Células do Cúmulo , Toluidinas , Animais , Bovinos , Dano ao DNA , Feminino , Oócitos , Toluidinas/toxicidadeRESUMO
In many species, alpha-lipoic acid (ALA) is essential for embryo development. There, therefore, was investigation of effects of ALA supplementation to culture media for in vitro development of cattle embryos. In Experiment I, there were assessments of embryo production and oxidative status of cattle embryos derived by in vitro maturation and fertilization (IVM/IVF)that were cultured until the blastocyst stage of development using different ALA concentrations (5, 25 and 100 µM), fetal bovine serum (FBS) and amino acids (aa) as well as 20 % oxygen (O2) in the culture atmosphere. In Experiment II, embryos were cultured without FBS, at different ALA concentrations (2.5, 5 and 7.5 µM) and in the presence or absence of aa when there was a 7 % O2 atmosphere. Embryo development rates and blastocyst quality were evaluated. With 20 % O2 concentration, treatment with 100 µM ALA resulted in lesser hatching rates and development to the blastocyst stage (P < 0.01), while with supplementation with 5 µM ALA there were lesser (P = 0.04) glutathione concentrations and greater protein contents of embryos (P < 0.01). Culturing in the 7 % O2 atmosphere, combined with supplementation with 2.5 µM ALA with FBS and aa resulted in a greater blastocyst cell number (P = 0.03) and lesser hatching rates (P = 0.04). Taken together, results indicate supplementation with the greater ALA concentrations resulted in impairment of embryo development, regardless of the O2 concentration imposed during the culture period, while the relatively lesser supplementation-concentrations with ALA led to improvements in embryo quality.
Assuntos
Blastocisto/efeitos dos fármacos , Bovinos/embriologia , Técnicas de Cultura Embrionária/veterinária , Ácido Tióctico/farmacologia , Animais , Técnicas de Cultura Embrionária/métodos , Transferência Embrionária/veterinária , Feminino , Peroxidação de LipídeosRESUMO
Selenium (Se) is an essential trace element with important functions in animals and whose deficiency is associated with reproductive failures. The aim of this study was to investigate the effect of Se concentrations during in vitro maturation (IVM) of Bos taurus oocyte within the reference ranges for Se status in cattle. For this purpose, Aberdeen Angus cumulus-oocyte complexes (COCs) were matured in IVM medium supplemented with 0, 10, 50, and 100 ng/mL Se (control, deficient, marginal, and adequate, respectively). The results demonstrated that marginal and adequate Se concentrations added during IVM increased viability and non-apoptotic cumulus cells (CC). Moreover, the addition of Se to culture media decreased malondialdehyde level in COC with all studied concentrations and increased total glutathione content in CC and oocytes with 10 ng/mL Se. On the other hand, total antioxidant capacity of COC, nuclear maturation, and the developmental capacity of oocytes were not modified by Se supplementation. However, 10 ng/mL Se increased hatching rate. In conclusion, supplementation with 10 ng/mL Se during in vitro maturation of Bos primigenius taurus oocytes should be considered to improve embryo quality.
Assuntos
Técnicas de Maturação in Vitro de Oócitos , Selenito de Sódio , Animais , Bovinos , Meios de Cultura , Células do Cúmulo , Feminino , Oócitos , Selenito de Sódio/farmacologiaRESUMO
The eicosapentaenoic acid (EPA) is an n-3 polyunsaturated fatty acid (PUFA) present in the lipid composition of bovine oocytes. Little is known about the importance of EPA in bovine oocyte maturation and embryo development in vitro. Although previous work suggest that n-3 PUFAs may inhibit oocyte maturation, the available data are inconsistent. In this study, we evaluated the effect of EPA (1, 10, 100 nM) during in vitro maturation (IVM) of bovine oocytes, alone and in combination with vitamin E (VE) or cysteamine (CYS). EPA treatment in IVM decreased oocyte lipid content and affected lipid droplets pattern (P < 0.05). EPA 100 nM reduced oocytes maturation rate (P < 0.05), without affecting cumulus expansion. At the concentrations tested, EPA did not modify embryo development. However, the addition of antioxidants during IVM reduced the levels of reactive oxygen species in the culture system by increasing intracellular glutathione content (P < 0.05). Besides, the combination of EPA with VE or CYS reduced the percentages of MI oocytes after 24 h of IVM (P < 0.05). EPA reduced oocyte lipid content without any detrimental for embryo development.
Assuntos
Ácido Eicosapentaenoico/farmacologia , Desenvolvimento Embrionário/efeitos dos fármacos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Lipídeos/química , Oócitos/efeitos dos fármacos , Animais , Antioxidantes , Bovinos , Cisteamina/administração & dosagem , Cisteamina/farmacologia , Eliminadores de Cistina/administração & dosagem , Eliminadores de Cistina/farmacologia , Ácido Eicosapentaenoico/administração & dosagem , Técnicas de Cultura Embrionária/veterinária , Oócitos/química , Vitamina E/administração & dosagem , Vitamina E/farmacologiaRESUMO
The objective of this study was to evaluate the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation to ewes during late gestation on finishing lamb liver and adipose tissue fatty acid (FA) profile and gene expression. Lambs born from ewes supplemented with Ca salts of EPA + DHA, or palm FA distillate (PFAD) high in palmitic and oleic acid at 0.39% DM during the last 50 d of gestation were used. Lambs were weaned at 61 d of age and adapted to a high concentrate diet for 1.5 mo. After adaptation, 74 lambs (28 pens) were blocked by sex and BW and used in a 2 × 2 factorial arrangement of treatments using the factors of dam supplementation (DS) and lamb supplementation (LS) of Ca salts of EPA + DHA or PFAD at 1.48% DM. Lambs were slaughtered after 42 d and liver and adipose tissue collected for FA and gene expression analysis. Liver concentrations of EPA and DHA were greater (P < 0.01) with LS of EPA + DHA vs. PFAD during the finishing period. In adipose tissue, a lamb × dam interaction was observed for EPA (P = 0.02) and DHA (P = 0.04); LS of EPA + DHA increased EPA and DHA, but the increase was greatest in lambs born from ewes supplemented with PFAD. No lamb × dam treatment interactions were observed for gene expression in liver tissue (P > 0.10). Hepatic mRNA abundance of hormone-sensitive lipase (HSL; P = 0.01) was greater in lambs born from EPA + DHA ewes vs. lambs from PFAD ewes. mRNA expression of stearoyl-CoA desaturase (P < 0.01), fatty acid synthase (P = 0.01), Δ5-desaturase (P < 0.01), and Δ6-desaturase (P < 0.01) were decreased in liver of EPA + DHA lambs. A significant lamb × dam diet interaction was observed for elongation of very long chain fatty acid 2 in adipose tissue (P = 0.01); lambs supplemented with the same FA as their dams had lower expression. Expression of HSL tended (P = 0.08) to be decreased in adipose of EPA + DHA lambs born from EPA + DHA ewes. The changes in mRNA expression suggest that lipogenesis decreased, and lipolysis increased in lamb liver with EPA + DHA vs. PFAD supplementation during the finishing period. In adipose tissue, changes suggest that lipogenesis decreased in lambs born from EPA + DHA supplemented dams and supplemented with EPA + DHA during the finishing period. In addition, these results suggest an interaction between supplementation of FA to dams during late gestation on lamb response of adipose tissue, but not liver, to FA supplementation during the finishing period.
Assuntos
Suplementos Nutricionais/análise , Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/farmacologia , Ácidos Graxos/farmacologia , Ovinos/fisiologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Ração Animal/análise , Animais , Cálcio/farmacologia , Dieta/veterinária , Ácido Eicosapentaenoico/análogos & derivados , Ácidos Graxos não Esterificados/metabolismo , Feminino , Lipogênese/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Parto/efeitos dos fármacos , Gravidez , Distribuição Aleatória , Ovinos/genética , DesmameRESUMO
We have developed a new method for the measurement of subcutaneous tumour volume which consists in taking photographs of mice in their home cages, to refine the standard method of measurement with calipers. We consider this new method to be non-aversive, as it may be more compatible with mice behavioural preferences and, therefore, improve their welfare. Photographs are captured when mice voluntarily go into an acrylic tube containing graph paper that is later used as a scale. Tumour volumes measured with the caliper and the non-aversive photographic method were compared to those obtained by water displacement volume and weight. Behavioural and physiological changes were evaluated to assess animal welfare. Significant differences were found between measurements obtained with the caliper and the non-aversive photographic method, v. the reference volume acquired by water displacement (P < 0.001). Nevertheless, there was good consistency for these measurements when tumours were measured repeatedly, with all Intra-Class Correlation Coefficients above 0.95. Mice on which the non-aversive photographic method was employed were significantly less reluctant to establish contact with the experimenter (P < 0.001) and behaved less anxiously in a modified-Novelty Suppressed Feeding test. Particularly, statistically significant differences were found in connection with the latency to eat an almond piece (P < 0.05), the frequency of grooming (P < 0.001) and the frequency of defecation (P < 0.001). Corticosterone concentration in faeces and blood glucose were determined and no significant changes were found. Therefore, we propose the non-aversive photographic method to measure subcutaneous tumours as a way to refine methodologies in the field of experimental oncology.
Assuntos
Camundongos Nus , Fotografação/métodos , Doenças dos Roedores/diagnóstico por imagem , Neoplasias de Tecidos Moles/diagnóstico por imagem , Carga Tumoral , Animais , Feminino , Masculino , Camundongos , Organismos Livres de Patógenos EspecíficosRESUMO
The objectives of this study were to evaluate the effect of feeding an enriched diet with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to finishing lambs born from ewes supplemented either with or without EPA and DHA during late gestation on productive performance, muscle fatty acid (FA), and hypothalamus mRNA concentration of metabolic genes and hormone receptors. Lambs born from dams fed during the last 50 d of gestation either with a control diet containing 0.39% Ca salts of palmitic fatty acid distillate (C) or Ca salts enriched with EPA and DHA (PFA) were used. After weaning lambs (n = 70) were blocked by weight (BW) and used in a 2 × 2 factorial into 2 finishing diets containing 1.5% of C or PFA. The 2 factors were the ewe diet and the finishing diet. Lambs (37.9 ± 0.4 kg) were weighed and blood sampled for glucose and NEFA measurements at days 1, 14, 28, and 42. Dry matter intake (DMI) was measured daily. At day 43, 14 females and 14 males were slaughtered, and hot carcass weight, body wall thickness, rib eye area, and FA composition of Longissumus thoracis muscle were evaluated. Female hypothalamuses were obtained and mRNA concentration of hormone receptors, neuropeptides, and their receptors was measured. Lambs born from PFA dams were heavier (P < 0.01). There was a time × finishing diet interaction for BW (P = 0.03), and lambs fed C had a greater BW. Lambs fed C had an increase in DMI (P < 0.01). There were no significant differences in plasma glucose and NEFA concentration (P > 0.1). Lambs born from PFA dams had a greater concentration of C22:0 (P < 0.03). Lambs fed C had higher concentrations of C18:1c15 (P < 0.01), C17:0 (P < 0.09), C18:0 (P < 0.09), and n6/n3 (P < 0.01). Lambs fed PFA had greater concentration (P < 0.05) of C16:1, C22:1, C20:5, C22:5, C22:6, total n3 FA, and total EPA and DHA. There was a significant dam × finishing diet interaction (P ≤ 0.08) on mRNA concentration for MCR3, CCK-R, Cort-R, and CART. Lambs, which had the same treatment as their dams, showed lower overall mRNA concentration than those with different treatments between them and their dams. Lambs born from PFA ewes had lower concentration of MCR4 mRNA (P = 0.09) than C. Agouti-related peptides mRNA concentration was lower in lambs fed PFA (P = 0.06) than C. In conclusion, changes on lamb performance, muscle fatty acid composition, and metabolic neuropeptides depend not only on the lamb diet, but also on the dam diet during late gestation.