RESUMO

Endometritis is the leading cause of mare subfertility. Most mares respond to standard therapy, but alternative therapies have been developed for mares failing to respond. This study aimed to investigate a commercially available, yet unassessed, product labeled as a uterine sanitizer to determine the in vitro antimicrobial activity against microorganisms associated with endometritis and its in vitro stability to dilute antibiotics. In experiment 1, the microdilution broth technique and antimicrobial effects were assessed against Escherichia sp, Staphylococcus sp., Klebsiella sp., Pseudomonas sp., and Candida sp. Percentage inhibition was calculated by comparing the optical density. The minimum inhibitory concentration (MIC) 100% was determined using the resazurin dye technique. MIC 50% and 90% were determined using a dose-response non-linear regression. In experiment 2, the uterine sanitizer was used to dilute commonly used antibiotics achieving a final volume of 90 mL at 5°C, 21°C, and 37°C. The pH was measured at 0, 1, 3, 6, and 24 h after dilution. The uterine sanitizer had inhibitory properties against all microorganisms; Escherichia sp. being the most susceptible, and Pseudomonas sp. the most resistant. The uterine sanitizer had an acidic pH=4; however, when combined with the antibiotics, the pH of the antibiotic remained unchanged with the different temperatures and did not precipitate. In conclusion, the uterine sanitizer showed antimicrobial effects against endometritis-causing microorganisms. The dilution of antibiotics in the uterine sanitizer was stable and this association could potentiate the antimicrobial effects. Uterine sanitizer's safety and clinical efficacy in vivo remain to be tested.

Assuntos

Antibacterianos , Bactérias , Endometrite , Doenças dos Cavalos , Testes de Sensibilidade Microbiana , Feminino , Animais , Endometrite/tratamento farmacológico , Endometrite/microbiologia , Endometrite/veterinária , Cavalos , Antibacterianos/farmacologia , Antibacterianos/química , Doenças dos Cavalos/tratamento farmacológico , Doenças dos Cavalos/microbiologia , Bactérias/efeitos dos fármacos , Estabilidade de Medicamentos

RESUMO

Persistent-breeding-induced endometritis (PBIE) is the leading cause of subfertility and poor reproductive efficiency in mares. Platelet-rich plasma (PRP) treatment has been shown to mitigate PBIE, reduce uterine infections, and improve fertility in mares. However, the proteome of PRP in mares, particularly those susceptible to PBIE, remains unknown. This study aimed to fill this knowledge gap by comparing the most abundant proteins present in PRP prepared from mares with histories of being susceptible or resistant to PBIE. The study involved twelve light-breed mares: seven susceptible and five resistant to PBIE. A complete blood count and physical examination were performed on each mare before blood drawing to ensure good health. The PRP was prepared following collection in a blood transfusion bag and double centrifugation. Platelet counts in the PRP were compared across the groups. The PRP was cryopreserved in liquid nitrogen until proteomics could be completed. Physical parameters and complete blood cell counts were within normal ranges. The platelet counts for resistant (561 ± 152 × 103) and susceptible mares (768 ± 395 × 103) differed (p < 0.05). One hundred and five proteins were detected in all mares, and four proteins were more abundant in resistant mares (p < 0.05). The proteins were apolipoprotein C-II, serpin family G member 1, protection of telomeres protein 1, and non-specific serine/threonine protein kinase. All these proteins are linked to the immune response. These results suggest that PRP prepared from mares resistant to PBIE may be more beneficial in mitigating PBIE in mares, offering a promising avenue for improving equine reproductive health. However, this remains to be determined with in vivo studies.

RESUMO

BACKGROUND: Artificial insemination with cooled-shipped semen is the primary method used in the equine breeding industry; yet, sperm quality and fertility can be suboptimal for some stallions when standard techniques are used. Therefore, there is a critical need to develop alternative approaches for these stallions. OBJECTIVE: To assess sperm quality parameters and fertility of cooled-stored stallion semen processed by SpermFilter® or centrifugation and resuspended in three extenders. STUDY DESIGN: Controlled and field study. METHODS: In Experiment 1, semen was collected from 21 stallions classified as having good ('Good-coolers', n = 8) or poor ('Bad-coolers', n = 13) semen cooling. The semen was extended at 30 million spermatozoa/mL in a skimmed milk-based (SM) diluent, and refrigerated for 24 h. Then, the cooled-stored semen was processed through SpermFilter® or centrifugation, and the resulting sperm pellets were resuspended in SM, SM containing pentoxifylline (SM-P), or an egg yolk-based (EY) extender. Unprocessed cooled-stored semen served as control. Sperm motility parameters, plasma membrane integrity (PMI), and mitochondrial membrane potential (HMMP) were assessed in cooled-semen pre- and post-processing. Experiment 2, cooled semen from 9 stallions classified as Bad-coolers was used to inseminate 18 embryo donor mares at 66 cycles (Unprocessed, n = 22; SpermFilter®/SM-P, n = 16; or SpermFilter®/EY, n = 28). Data were analysed with a mixed model and Tukey's as posthoc, and logistic regression. RESULTS: Processed semen resuspended in EY had superior sperm motility compared to unprocessed, SM and SM-P (p < 0.0001). Semen processed by SpermFilter® resuspended in SM-P was similar to EY (p > 0.05). Pellet resuspension with EY and SM-P improved the HMMP of Bad-cooler stallions (p = 0.0010). Semen processed by SpermFilter® had superior PMI to centrifuged semen (p < 0.0001). Mares inseminated with SpermFilter®/SM-P (50%, 8/16) or SpermFilter®/-EY (68%, 9/28) had higher pregnancy rates than mares bred with unprocessed semen (14%, 3/22) (p < 0.001). MAIN LIMITATIONS: Low number of mares in the fertility trial. CONCLUSION: Sperm quality and fertility of Bad-cooler stallions can be enhanced by SpermFilter® and pellet resuspension with either EY or SM-P.

Assuntos

Inseminação Artificial , Preservação do Sêmen , Animais , Cavalos/fisiologia , Masculino , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Inseminação Artificial/veterinária , Feminino , Espermatozoides/fisiologia , Análise do Sêmen/veterinária , Sêmen/fisiologia , Gravidez , Criopreservação/veterinária , Criopreservação/métodos , Motilidade dos Espermatozoides , Temperatura Baixa

RESUMO

Less invasive rumen sampling methods, such as oro-esophageal tubing, became widely popular for exploring the rumen microbiome and metabolome. However, it remains unclear if such methods represent well the rumen contents from the rumen cannula technique. Herein, we characterized the microbiome and metabolome in the rumen content collected by an oro-esophageal tube and by rumen cannula in ten multiparous lactating Holstein cows. The 16S rRNA gene was amplified and sequenced using the Illumina MiSeq platform. Untargeted metabolome was characterized using gas chromatography of a time-of-flight mass spectrometer. Bacteroidetes, Firmicutes, and Proteobacteria were the top three most abundant phyla representing ~ 90% of all samples. Although the pH of oro-esophageal samples was greater than rumen cannula, we found no difference in alpha and beta-diversity among their microbiomes. The overall metabolome of oro-esophageal samples was slightly different from rumen cannula samples yet more closely related to the rumen cannula content as a whole, including its fluid and particulate fractions. Enrichment pathway analysis revealed a few differences between sampling methods, such as when evaluating unsaturated fatty acid pathways in the rumen. The results of the current study suggest that oro-esophageal sampling can be a proxy to screen the 16S rRNA rumen microbiome compared to the rumen cannula technique. The variation introduced by the 16S rRNA methodology may be mitigated by oro-esophageal sampling and the possibility of increasing experimental units for a more consistent representation of the overall microbial population. Studies should consider an under or over-representation of metabolites and specific metabolic pathways depending on the sampling method.

Assuntos

Lactação , Microbiota , Animais , Feminino , Bovinos , RNA Ribossômico 16S/genética , Rúmen/microbiologia , Cânula , Metaboloma

RESUMO

Misoprostol, a synthetic PGE1, is becoming a common therapy for mares with suspected uterine tube obstruction. Recently, there have been concerns that uterine administration of misoprostol induces exacerbated uterine inflammation; however, this has not been critically evaluated. This study aimed to assess the inflammatory response and potential systemic reactions after uterine administration of misoprostol, either during prebreeding or immediately after postembryo flushing. Privately owned embryo donor mares (n = 11) were randomly assigned in a crossover design to receive misoprostol (3 mL +200 µg) or sham (3 mL of lactate Ringer's solution) infusions, bilaterally deposited via deep-horn, at least 72 hours prebreeding (experiment 1) or immediately after embryo flushing (experiment 2). Each mare had one cycle for misoprostol and sham in both experiments and a breeding cycle (no sham or misoprostol) between experiments. Uterine edema, fluid accumulation, and the number of uterine PMN were assessed before each infusion and then daily for 72 hours. Uterine lavage was performed the day after each infusion across groups and experiments. Ovulation was hastened with a GnRH agonist and confirmed at 24 hour-intervals. Mares were bred with semen from one of six stallions per owner's choice. Embryo flushing was performed 8 to 9 days postovulation. In either experiment, misoprostol did not affect uterine edema or fluid accumulation (P > .05). However, both the sham and misoprostol infusions increased the number of PMN up to 48 hours postinfusion in both experiments. Embryo recoveries were similar between sham (45%, 5/11) and misoprostol cycles in experiments 1 (45%, 5/11; P > .05) and 2 (sham, 68%, 7/11; misoprostol, 45%, 5/11; P > .05). In conclusion, misoprostol did not induce exacerbated uterine inflammation in mares or systemic adverse reactions when infused prebreeding or immediately after embryo flushing.

Assuntos

Doenças dos Cavalos , Misoprostol , Doenças Uterinas , Alprostadil , Animais , Edema/veterinária , Feminino , Hormônio Liberador de Gonadotropina , Cavalos , Inflamação/induzido quimicamente , Inflamação/veterinária , Lactatos , Masculino , Misoprostol/efeitos adversos , Solução de Ringer , Doenças Uterinas/veterinária

RESUMO

Nocardioform placentitis is a pathologically unique form of placental disease first diagnosed in central Kentucky in the mid-80s. Since then, the occurrence of nocardioform placentitis in the region has varied over the years, from sporadic cases to outbreaks. The disease has been sporadically detected in other countries and has not been confirmed in South America. A 13-year-old multiparous Mangalarga delivered a healthy filly at 340d gestation. The mare passed the fetal membranes 33 minute after foaling. Gross examination of the fetal membranes identified two focal lesions on the chorionic surface consistent with focal mucoid placentitis. Histopathologic evaluation revealed hyperplasia and degeneration of the allantoic mesoderm, intense mononuclear inflammatory infiltrates with marked lymphocytes and plasma, and occasional macrophages and neutrophils in the microvilli. Necrotic debris and exudate were identified in the chorionic epithelium, with macrophages, plasma cells, and neutrophils confirming the diagnosis of focal mucoid placentitis. The exudate culture revealed white, firm, punctiform colonies of ∼1 mm diameter. Gram staining revealed bacilli with rounded ends and branching aspect typical of actinomycetes. PCR using primers for the 16S rRNA identified the genera of bacteria as Amycolatopsis. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis identified the isolate as Amycolatopsis lexingtonensis. In conclusion, we described the first confirmed case of nocardioform placentitis in South America. The present case was associated with the birth of a full-term healthy live foal; this result is consistent with Amycolatopsis spp and, in this case, was caused by A. lexingtonensis.

Assuntos

Doenças dos Cavalos , Doenças Placentárias , Amycolatopsis , Animais , Feminino , Doenças dos Cavalos/epidemiologia , Cavalos , Placenta/microbiologia , Doenças Placentárias/epidemiologia , Doenças Placentárias/veterinária , Gravidez , RNA Ribossômico 16S/genética

RESUMO

The objectives of this study were: (1) to assess uterine features and serum progesterone concentrations of acyclic mares synchronized and resynchronized with intravaginal progesterone release device (IPRD), and (2) to compare pregnancy rates and losses of cyclic and acyclic embryo recipient mares treated with different synchronization protocols. In Experiment 1, mares (n = 12) received estradiol for 3 days (E2-3d), and then 24 h after the last injection, an IPRD was inserted and kept in place for 9 days. Three days after IPRD removal, mares were treated with E2-3d, and then a new IPRD was inserted and maintained for three days. Serum progesterone concentrations were assessed 2, 6, and 12 h after insertion and removal of IPRD, and then daily from the insertion of the first IPRD to one day after removal of the second IPRD. Experiment 2 was conducted with embryo recipient mares randomly assigned to four groups: (1) Cyclic: mares (n = 75) had ovulation confirmed after receiving a single dose of histrelin when a periovulatory follicle was first detected, (2) LAP4: acyclic mares (n = 92) were treated with E2-3d and then administered a single dose of LAP4 24 h after the last estradiol injection, (3) IPRD: acyclic mares (n = 130) were treated with E2-3d and an IPRD for 4-8 days, and (4) RE-IPRD: acyclic mares (n = 32) were synchronized as in the IPRD group but not used for embryo transfer (ET), then 8 to 15 days later, the mares were resynchronized with E2-3d and an IPRD for 4-8 days. In vivo-produced Day-8 embryos were collected and transferred 4-8 days after ovulation or progesterone treatments. Mares in IPRD and RE-IPRD groups had the intravaginal device removed immediately before ET, and then a new IPRD was inserted right after ET. Pregnancy diagnosis was performed at 5, 30, and 60 days after ET. Once pregnancy was confirmed, mares in the three acyclic groups received weekly injections of LAP4 (1.5 g) until 120 days of pregnancy. Mares in IPRD and RE-IPRD groups had the device removed three days after the first pregnancy diagnosis. In Experiment 1, progesterone concentrations increased rapidly starting 2 h after insertion of IPRD (p < 0.05); then, concentrations plateaued well above pregnancy maintenance until removal on days 9 and 3, respectively. Progesterone concentrations were reduced to baseline 24 h after IPRD removal (p < 0.05). For experiment 2, there was no difference in pregnancy rates across groups (65-74%) or pregnancy losses by 60 days of gestation (7-12%) (p > 0.05). In conclusion, the IPRD used herein resulted in a rapid increase and a sharp decline in progesterone concentrations upon its insertion and removal, respectively. Finally, our results demonstrated that IPRD could be a compatible alternative to LAP4 to synchronize and resynchronize acyclic embryo recipient mares.

RESUMO

This study compared the postthaw semen parameters of stallions with high and low body condition score (BCS) and evaluated associations between body morphometric parameters and postthaw semen parameters. Twenty stallions were split into Low BCS (BCS<7, n = 11) and High BCS (BCS ≥7, n = 9) groups, and underwent a complete morphometric analysis (e.g., neck scores and circumference, crest neck height, body weight, and height), and subcutaneous body fat thickness (SFT) at the tail head, withers, shoulders, and retroperitoneal space. A fasted oral sugar test (OST) was conducted on all stallions. One ejaculate from each stallion was frozen with a commercial egg yolk-based extender. Postthaw sperm motility parameters, plasma membrane integrity, mitochondrial membrane potential, hydrogen peroxide and intracellular superoxide production, and lipid peroxidation were analyzed for all stallions. The circumference at 25% and 50% of the neck's length were larger for High-BCS stallions (P < .05). There were no differences between groups for the neck crest height (P > .05). Stallions with High BCS had greater SFT at the tail head than stallions with Low BCS (P < .05); however, there were no differences between groups in the SFT at the shoulders and withers (P > .05). All stallions had resting blood glucose below the cutoff for equine metabolic syndrome. There were no differences between groups for resting glucose concentrations or for a peak at 30 or 60 minutes after initiation of the OST (P > .05). There were no differences in sperm parameters between groups (P > .05). Collectively, the findings of the present study suggest that High BCS or Low BCS in the presence of normal OST do not explain post-thaw semen parameters.

Assuntos

Preservação do Sêmen , Sêmen , Tecido Adiposo , Animais , Criopreservação/veterinária , Cavalos , Masculino , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Açúcares

RESUMO

BACKGROUND: Neonatal sepsis is a leading cause of neonatal death during the first-week postfoaling. Despite recent advancements in the diagnosis and treatment of sepsis in the newborn foal, the non-specific clinical signs and subtle nature of this disease may result in delayed diagnosis until severe progression of the disease; thus, early detection of sepsis remains critical for a favourable outcome. This study aimed to identify early blood markers as predictive of sepsis on foals. METHODS: Thirty-five foals were allocated into three groups: healthy control foals (n=7) and foals born from mares with placentitis: septic foals (n=9) and non-septic foals (n=19). Blood samples were obtained immediately after foaling and at 12, 24 and 48 hours. All samples were assessed for glucose, lactate, triglycerides, total cholesterol, urea, creatinine, total solids, fibrinogen, gamma-glutamyl transferase (GGT), serum amyloid A (SAA) and alpha-fetoprotein (AFP) concentrations. RESULTS: At foaling, glucose and GGT concentrations were lower in septic foals (P<0.001). Of interest, SAA, AFP, creatinine and total cholesterol were higher in septic foals at parturition (P<0.05). At 12 hours, lactate, triglycerides and total cholesterol concentrations were higher in septic foals. When evaluated at 24 and 48 hours, higher concentrations of SAA and AFP were found in placentitis foals than in the control group. CONCLUSIONS: Total cholesterol and lactate appear to be suitable markers for sepsis during the first 24 hours postpartum. Septic foals displayed altered energy metabolisms as determined by increased triglycerides and cholesterol concentrations, hypoglycaemia at birth and reduced activity of the GGT and increased lactate and urea concentrations. Sepsis was associated with high concentrations of SAA and AFP.

Assuntos

Animais Recém-Nascidos/sangue , Biomarcadores/sangue , Doenças dos Cavalos/sangue , Sepse/veterinária , Animais , Estudos de Casos e Controles , Feminino , Cavalos , Parto , Doenças Placentárias/etiologia , Doenças Placentárias/veterinária , Gravidez , Sepse/sangue , Proteína Amiloide A Sérica/análise , alfa-Fetoproteínas/análise

RESUMO

This study aimed to evaluate steroid hormones in foals born from mares treated for ascending placentitis with different combinations of trimethoprim-sulfamethoxazole (TMS), flunixin meglumine (FM), long-acting altrenogest (ALT) and estradiol cypionate (ECP) for ten consecutive days, starting two days after experimental induction of placentitis with Streptococcus zooepidemicus. Fourty-six pregnant mares and respective foals were assigned as healthy group (Control, n = 8) or treated groups as follows: TMS+FM (n = 8), TMS+FM+ALT (n = 8), TMS+FM+ALT+ECP (n = 6), TMS+FM+ECP (n = 6) and no treatment (NO TREAT n = 10). At delivery, foals were classified as high-risk or low-risk based on clinical and hematologic findings, and survival rates were recorded during the first week of life for comparisons across groups. Cortisol, progesterone, 17αOHprogesterone, and pregnenolone concentrations were determined via immunoassays in 31 of the 46 foals immediately after foaling (0 h), at 12, 24, 48 h, and seven days post-partum (168h). At birth, serum cortisol concentrations were higher in Control and TMS+FM+ECP foals than in remaining groups (p < 0.05). Foals in TMS+FM+ALT and TMS+FM groups had higher 17αOHprogesterone concentrations at 24 h and 48 h, respectively (p < 0.05). Pregnenolone concentrations were higher in TMS+FM than TMS+FM+ALT+ECP foals at 7 days (p < 0.05). High-risk and non-surviving foals had decreased concentrations of cortisol at parturition, but increased concentrations of progesterone from 0 h to 48 h. Pregnenolone and 17αOHprogesterone concentrations were increased and pregnenolone after 12 h in high-risk and non-surviving foals (p < 0.05). In conclusion, adding ECP to the treatment of experimentally-induced placentitis appears to improve foal viability and endocrine response. Cortisol and progestogen profiles were abnormal in high-risk and non-surviving foals, and those treated with ALT or TMS+FM only.

Assuntos

Doenças dos Cavalos/microbiologia , Hidrocortisona/sangue , Doenças Placentárias/veterinária , Pregnenolona/sangue , Progesterona/sangue , Infecções Estreptocócicas/veterinária , 17-alfa-Hidroxiprogesterona/sangue , Animais , Animais Recém-Nascidos , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Clonixina/administração & dosagem , Clonixina/análogos & derivados , Clonixina/uso terapêutico , Anticoncepcionais Femininos/administração & dosagem , Anticoncepcionais Femininos/uso terapêutico , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Estradiol/uso terapêutico , Feminino , Cavalos , Doenças Placentárias/microbiologia , Gravidez , Progestinas/administração & dosagem , Progestinas/uso terapêutico , Distribuição Aleatória , Streptococcus equi , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/análogos & derivados , Acetato de Trembolona/uso terapêutico , Combinação Trimetoprima e Sulfametoxazol/administração & dosagem , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico

RESUMO

This study aimed to evaluate the antioxidant properties of coenzyme Q10 (CoQ10) during cryopreservation of semen obtained from stallions having good and bad semen freezing ability (GFA vs. BFA, respectively). Forty ejaculates (n = 20 stallions) were split into five centrifugation and five freezing extenders containing different concentrations of CoQ10 (0, 25, 50, 75 and 100 µmols/L). If CoQ10 was added to the centrifugation extender, the freezing extender had no CoQ10 added; similarly, if CoQ10 was added to the freezing extender, the centrifugation extender had no CoQ10. Semen cryopreserved on extenders containing no CoQ10 served as the control. After post-thaw total sperm motility (TM) assessments, the stallions were classified as GFA (i.e., decrease of ≤25% in TM, n = 7) or BFA (i.e., decrease of ≥40% in TM, n = 5). Stallions not fitting (n = 8) this enrollment criteria had samples discarded. After that, two straws for each extender were thawed at 37 °C for 30 s; one straw was immediately used for evaluation of sperm kinetics, plasma membrane integrity, non-capacitated spermatozoa, reactive oxygen species production, mitochondrial activity and lipid peroxidation. The second straw was kept at 37 °C for 30 min and subjected to the same assessments. Expectedly, sperm motility parameters were significantly lower for stallions with BFA. There were no effects of CoQ10 concentration or time for all parameters evaluated in the group with GFA when compared with the control extender (p > 0.05), except lipid peroxidation (p < 0.05). However, stallions with BFA had improved sperm parameters for samples processed with extenders containing CoQ10 (particularly 75 µmols/L) (p < 0.05), except for the reactive oxygen species production and mitochondrial potential (T0) in which there were no differences between the groups (p > 0.05). In summary, 75 µmols/L appears to be the optimal dose of Co-Q10, particularly, when added to the centrifugation extender.

Assuntos

Criopreservação/veterinária , Cavalos/fisiologia , Preservação do Sêmen/veterinária , Ubiquinona/análogos & derivados , Animais , Congelamento , Masculino , Ubiquinona/farmacologia

RESUMO

This study compared hormone treatments given to mares during anestrus, spring transition, and different stages of the estrous cycle, by assessing uterine features and pregnancy rates after embryo transfer (ET). Embryo recipient mares (n = 160) were equally arranged as follows: G1-spontaneous ovulation (control), G2-anestrus, G3-spring transition, G4-early estrus, G5-estrus, G6-diestrus, G7-early diestrus treated with a dose of dinoprost, and G8-early diestrus treated with two doses of dinoprost. At treatment initiation (Day-4), G2-7 were given dinoprost and estradiol-17ß, thereafter, estradiol-17ß was repeated on Days-3,-2, and -1. On Day0, mares received long-acting altrenogest. Then, each mare had one ET performed from Day + 3 to Day + 8 after altrenogest. Immediately before the ET, mares received a boost of altrenogest and had uterine features assessed. Pregnant mares on each of the checks (by 7, 30, 60, and 120d after ET) were maintained on weekly injections of LA-P4 until 120d. G8 received similar management, but dinoprost was repeated on Day-3. G1-G6 and G8 displayed uterine edema and satisfactory pregnancy rates ≥65%. Repeating dinoprost to G8 likely ensured proper luteolysis and response to estrogen as determined by higher uterine edema scores and pregnancy rates than G7 (p < .05). Our results were consistent with previous studies and other successful commercial ET programs (except G7), thus, demonstrating the usefulness of the hormone treatments described herein to synchronize embryo recipient mares with donor mares. Thus, we foresee that other groups may use the strategies described herein for the management of embryo recipient mares.

Assuntos

Dinoprosta/farmacologia , Transferência Embrionária/veterinária , Estradiol/farmacologia , Cavalos/fisiologia , Acetato de Trembolona/análogos & derivados , Anabolizantes/administração & dosagem , Anabolizantes/farmacologia , Animais , Dinoprosta/administração & dosagem , Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Estrogênios/farmacologia , Ciclo Estral , Sincronização do Estro , Feminino , Ocitócicos/administração & dosagem , Ocitócicos/farmacologia , Gravidez , Taxa de Gravidez , Progesterona/farmacologia , Progestinas/farmacologia , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/farmacologia

RESUMO

The world horse industry exerts an important role as a job and income generation source. Reproductive technologies arises as an important tool in the service of world equine growth. Artificial insemination (AI) is perhaps the biotechnology with greater impact on equine breeding; a stallion can leave hundreds of offsprings over his reproductive life if AI is efficiently used. In some countries, egg yolk is frequently used as part of equine seminal extenders. The egg yolk provides the spermatozoa "resistance factors'' when it is added. The protective fraction of the egg yolk probably is the low density lipoproteins (LDL). Several studies have reported successful results with the addition and replacement of egg yolk by LDL. There are many citations about the use of egg yolk in seminal extenders for stallion's cooled and frozen semen, and in the equine reproduction practice. The egg yolk dilutors are used with good fertility results. New research is needed for the better understanding of the protective effects of egg yolk and the LDL for stallion semen. The LDL would be a great solution for dilutors to artificial insemination in horse. This review discusses the use and the advantages of egg yolk and LDL as constituents of equine semen extenders.

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La industria equina ejerce un importante papel como fuente generadora de empleo y renta. Las biotecnologías de la reproducción constituyen una valiosa herramienta para la mejora mundial en la especie equina. Dentro de las técnicas se encuentra la inseminación artificial (IA), que probablemente es la biotecnología con mayor impacto en la equino-cultura, una vez que un garañón pueda producir centenas de productos de buena calidad a lo largo de su vida reproductiva. En algunos países la yema de huevo es utilizada como medio de dilución para semen equino, porque puede proporcionar a los espermatozoides "factores de resistencia". Los efectos protectores de este medio probablemente sean ejercidos por las lipoproteínas de baja densidad (LDL). Diversos estudios han relatado el suceso cuando substituyen yema de huevo por LDL. También existen trabajos orientados a la utilización de yema de huevo como constituyente del medio de dilución para semen de garañones conservados a temperaturas de refrigeración y congelación. Se requiere de nuevas investigaciones para entender los mecanismos protectores de la yema del huevo y las LDL para el semen del garañón. El objetivo de la presente revisión fue contextualizar sobre la utilización de la yema de huevo y las LDL como medio de dilución del semen equino, pudiéndose esta última, constituir en una gran solución como medio de dilución en la inseminación artificial de esta especie animal.

Assuntos

Gema de Ovo , Cavalos , Lipoproteínas LDL , Sêmen