RESUMEN
The objectives of the study were to determine (1) oestrous expression rate and (2) the effect of oestrous expression prior to progesterone-based Ovsynch protocol on pregnancy rate in Holstein cows. All cows (n = 917) were subjected to 7-day progesterone-based Ovsynch protocol. In this protocol, cows that expressed oestrus before (HEAT1) the scheduled second GnRH were inseminated 20 h later after the onset of oestrus without GnRH administration. Cows that expressed oestrus after the second GnRH administration (HEAT2) or did not express oestrus (NOHEAT) received fixed-timed AI. Oestrous expression was determined by using activity-rumination monitoring system and all cows were inseminated with sexed semen. Oestrous expression rate prior to FTAI was 40.5% and the majority (p < .01) of oestrous expression were in HEAT2 compared with HEAT1 in both primiparous (71.8 vs. 28.1%) and multiparous cows (69.5 vs. 30.5%). The mean interval from intravaginal device removal to the onset of oestrus was 47.4 ± 0.9 h and 62.9 ± 0.5 in HEAT1 and HEAT2, respectively. Primiparous cows (47.7%) had a higher (p < .01) expression rate compared with multiparous cows (37.2%). Overall pregnancy rate was 37.4% and there was two-way significant interaction between parity and oestrous expression on pregnancy rate (p < .01). Both primiparous (48.1 vs. 35.8%) and multiparous cows (47.4 vs. 28.4%) that expressed oestrus had greater (p < .01) pregnancy rate compared with cows that did not express oestrus. There was no difference in pregnancy rates of HEAT1 and HEAT2 in both primiparous (44.7 vs. 49.5%) and multiparous cows (47.2 vs. 47.6%). Pregnancy rate was not influenced (p = .21) by milk production (high or low) in both primiparous (47.6 vs. 48.6%) and multiparous (54.9 vs. 42.1%) cows that expressed oestrus, respectively. In conclusion, cows showing oestrus before or after second GnRH of the Ovsynch protocol had greater pregnancy rate than cows not showing oestrus.
Asunto(s)
Progesterona , Semen , Embarazo , Femenino , Bovinos , Animales , Progesterona/farmacología , Sincronización del Estro/métodos , Inseminación Artificial/veterinaria , Inseminación Artificial/métodos , Hormona Liberadora de Gonadotropina/farmacología , Dinoprost , LactanciaRESUMEN
The objective of the study was to evaluate the interval from onset of oestrus to time of artificial insemination (AI) to obtain the optimum pregnancy rate with sex-sorted semen in Holstein heifers. Heifers in oestrus were detected and inseminated only by using heat-rumination neck collar comprised electronic identification tag at the age of 13-14 months. Heifers (n = 283) were randomly assigned to one of three groups according to the timing of insemination at 12-16 hr (G1, n = 97), at 16.1-20 hr (G2, n = 94) and at 20.1-24 hr (G3, n = 92) after reaching the activity threshold. The mean duration of oestrus was 18.6 ± 0.1 hr, and mean peak activity was found at 7.5 ± 0.1 hr after activity threshold. The mean interval from activity threshold to ovulation was 29.4 ± 0.4 hr. The overall pregnancy per AI (P/AI) was 53.0% at 29-35 days and 50.9% at 60-66 days after AI. There was a significant reduction between G1 (13.8 ± 1.4 hr) and G3 (7.9 ± 1.4 hr) related to the intervals from AI to ovulation time. Sex-sorted semen resulted in significantly higher P/AI at 29-35 days when heifers inseminated in G3 (60.9%) after oestrus than those inseminated in G1 (49.5%) and G2 (48.9%). In terms of fertility, when the temperature-humidity index (THI) was below the threshold value (THI ≤65) at the time of AI, there was a tendency (≤65; 57.2% vs. > 65; 47.1%) for high pregnancy rate. There was no effect of sire on P/AI. In addition, the interaction of the technician with the time of AI was found significant, and three-way interaction of technician, sire and time of AI was tended to be significant on pregnancy rate. Thus, in addition to delaying the time of insemination (between 20.1 and 24 hr) after oestrous detection, THI and experienced technician were also found to be critical factors in increasing fertility with the use of sex-sorted semen in Holstein heifers.
Asunto(s)
Bovinos/fisiología , Inseminación Artificial/veterinaria , Índice de Embarazo , Animales , Estro , Femenino , Fertilidad , Respuesta al Choque Térmico , Inseminación Artificial/métodos , Masculino , Embarazo , Preselección del Sexo/veterinaria , Factores de Tiempo , TurquíaRESUMEN
Colostrum, an invaluable food produced by mammals during the postnatal period, contains important bioactive components. It is a valuable therapeutic substance that can be used to treat a variety of disorders, in addition to its primary function of providing passive immunity to newborns. Undoubtedly, a strong dedication to intense effort and demanding training schedules is necessary to succeed in today's sports environment. Peak physical fitness, strategic skill development, and mental toughness are highly valued in the environments in which athletes compete. However, the inherent difficulties brought about by athletes' intense schedules are matched with the demanding character of modern sports. The intensity of athletic activity frequently provides little time for sufficient relaxation, nutritional preparation, and overall recovery, which can contribute to mental and physical tiredness. Athletes need to develop all-encompassing strategies to overcome these obstacles. These strategies should prioritize self-care and recovery in addition to maximizing training efficiency. The bioactive components of colostrum bring forth various therapeutic effects against the challenges experienced by athletes; including diarrhea, upper respiratory tract infections, muscle injuries, intestinal disorders, etc. This review examined the different therapeutic effects of the bioactive components of colostrum on athletes, the effect of the use of colostrum as a whole on the performance of athletes, and the clinical research conducted in this field. While the majority of studies report positive effects of colostrum, further research is needed.
Asunto(s)
Atletas , Calostro , Suplementos Dietéticos , Calostro/inmunología , Humanos , Ensayos Clínicos como Asunto , Femenino , Rendimiento Atlético , AnimalesRESUMEN
Colostrum is the first milk produced post-partum by mammals and is compositionally distinct from mature milk. Bovine colostrum has a long history of consumption by humans, and there have been a number of studies investigating its potential for applications in human nutrition and health. Extensive characterization of the constituent fractions has identified a wealth of potentially bioactive molecules, their potential for shaping neonatal development, and the potential for their application beyond the neonatal period. Proteins, fats, glycans, minerals, and vitamins are abundant in colostrum, and advances in dairy processing technologies have enabled the advancement of bovine colostrum from relative limitations of a fresh and unprocessed food to a variety of potential applications. In these forms, clinical studies have examined bovine colostrum as having the substantial potential to improve human health. This review discusses the macro-and micronutrient composition of colostrum as well as describing well-characterized bioactives found in bovine colostrum and their potential for human health. Current gaps in knowledge are also identified and future directions are considered in order to elevate the potential for bovine colostrum as a component of a healthy diet for a variety of relevant human populations.
RESUMEN
Protein glycosylation is a diverse and common post-translational modification that has been associated with many important roles such as protein function, including protein folding, stability, enzymatic protection, and biological recognition. N-glycans attached to glycoproteins (such as lactoferrin, lactadherin, and immunoglobulins) cannot be digested by the host and reach the large intestine, where they are consumed by certain beneficial microbes. Therefore, they are considered next-generation prebiotic compounds that can selectively stimulate the gut microbiome's beneficial microorganisms. However, the isolation of these new classes of prebiotics requires novel enzymes. Here, we describe the recombinant production of novel glycosidases from different Bifidobacteria strains (isolated from infants, rabbits, chicken, and bumblebee) for improved N-glycan isolation from glycoproteins. The method presented in this study includes the following steps: molecular cloning of Bifidobacterial genes by an in vivo recombinational cloning strategy, control of transformation success, protein induction, and protein purification.
Asunto(s)
Bifidobacterium , Glicósido Hidrolasas , Animales , Glicoproteínas/metabolismo , Glicósido Hidrolasas/genética , Glicósido Hidrolasas/metabolismo , Glicosilación , Polisacáridos , ConejosRESUMEN
Colostrum is a complex biological fluid produced by mammals immediately after parturition. It meets all the nutritional requirements for neonates as a good source of macro- and micronutrients, bioactive peptides, and growth factors. Bovine colostrum is also a potential source of nutrition and bioactive because of its rich protein content that includes immunoglobulin G (IgG) and lactoferrin. However, the level of lactoferrin and IgG in bovine colostrum changes markedly during the lactation period. Therefore, monitoring the concentration of IgG and lactoferrin for the use of bovine colostrum as a protein source is an important question to study. Methods in this article describe how to determine protein content, as well as specific concentrations of lactoferrin and IgG. These methods include the following steps: Isolation of bovine colostrum proteins, Determination of protein concentration via Bicinchoninic acid assay (BCA), Visualization of proteins via SDS-PAGE, Determination of lactoferrin, and IgG concentration using an ELISA Assay.
Asunto(s)
Calostro , Lactancia , Animales , Bovinos , Calostro/química , Ensayo de Inmunoadsorción Enzimática , Femenino , Inmunoglobulina G , Mamíferos , EmbarazoRESUMEN
Colostrum contains all essential nutrients for the neonate during the first days of life, with impacts that continue far beyond these first days. Bovine colostrum has been used for human consumption due to the high concentrations of bioactive proteins, vitamins, minerals, growth factors, as well as free and conjugated oligosaccharides. Processes involved in the preparation of bovine colostrum for human consumption play a pivotal role in preserving and maintaining the activity of the bioactive molecules. As bovine colostrum is a multifunctional food that offers a myriad of benefits for human health, assessing the main processes used in preparing it with both advantages and disadvantages is a crucial point to discuss. We discuss major processes effects for colostrum production on the nutritional value, some advanced technologies to preserve processed bovine colostrum and the end-product forms consumed by humans whether as dairy products or dietary supplements.
RESUMEN
Recently we demonstrated that centrally administrated melittin, a phospholipase A(2) (PLA(2)) activator, caused pressor and bradycardic effect in the normotensive conscious rats. In the current study we aimed to determine the mediation of central cholinergic system in the pressor and bradycardic effect of centrally administrated melittin. Studies were performed in normotensive male Sprague-Dawley rats. 1.5, 3.0 or 6.0microg/5.0microl doses of melittin were injected intracerebroventricularly (i.c.v.). Melittin caused dose- and time-dependent increases in mean arterial pressure (MAP) and decrease in heart rate (HR). In order to test the mediation of central cholinergic system on the pressor and bradycardic effect of melittin, the rats were pretreated with mecamylamine (50microg; i.c.v.), cholinergic nonselective nicotinic receptor antagonist, atropine sulfate (10microg; i.c.v.), a cholinergic nonselective muscarinic receptor antagonist, hemicholinium-3 (20microg; i.c.v.), a high affinity neuronal choline uptake inhibitor, methyllycaconitine (10 and 25microg; i.c.v.) or alpha-bungarotoxin (10 and 25microg; i.c.v.), selective antagonists of alpha-7 subtype nicotinic acetylcholine receptors (alpha7nAChRs), 15min prior to melittin (3.0microg) injection. Pretreatment with mecamylamine, hemicholinium-3, methyllycaconitine or alpha-bungarotoxin partially attenuated the pressor and bradicardia effect of elicited by melittin in the normotensive conscious rats whereas pretreatment with atropine had no effect. In conclusion, i.c.v. administration of melittin increases MAP and decreases HR in conscious rats. The activation of central nicotinic cholinergic receptors, predominantly alpha7nAChRs, partially acts as a mediator in the pressor responses to i.c.v. injection of melittin in the normotensive conscious rats. Moreover, decreased uptake of choline to the cholinergic terminals may consider that melittin activates central choline and acetylcholine release, as well.
Asunto(s)
Presión Sanguínea/efectos de los fármacos , Bradicardia/inducido químicamente , Encéfalo/efectos de los fármacos , Fibras Colinérgicas/efectos de los fármacos , Meliteno/farmacología , Aconitina/análogos & derivados , Aconitina/farmacología , Animales , Atropina/farmacología , Presión Sanguínea/fisiología , Bradicardia/fisiopatología , Encéfalo/fisiología , Bungarotoxinas/farmacología , Colinérgicos/farmacología , Fibras Colinérgicas/fisiología , Estado de Conciencia , Interacciones Farmacológicas , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Hemicolinio 3/farmacología , Inyecciones Intraventriculares , Masculino , Mecamilamina/farmacología , Antagonistas Nicotínicos/farmacología , Parasimpatolíticos/farmacología , Fosfolipasas A/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
Erythropoietin (EPO) is a hematopoietic factor, which is produced primarily by the adult kidney in response to tissue hypoxia. There is strong evidence that EPO may also be synthesized in the brain and act as a neuroprotector or neuromodulator in the central nervous system. The present study investigated the effect of centrally administered EPO on cardiovascular and respiratory parameters in anaesthetized rats. The animals were anaesthetized with ketamine (70 mg/kg) and xylazine (10 mg/kg) mixture. EPO at doses of 0.06, 0.12, 0.25 and 0.50 IU/5 microl or 0.9% saline as a control were injected intracerebroventricularly and blood pressure, heart rate, respiratory rate, tidal volume and minute ventilation were recorded. Following the administration of EPO, there was a significant increase in blood pressure, heart and respiratory rates, tidal volume and minute ventilation which were time and dose dependant. In order to investigate whether these effects of centrally injected EPO was caused by the diffusion of the drug to the periphery, the highest dose EPO (0.5 IU) in the present study, was injected intravenously but intravenously injected EPO showed no significant effect in these parameters. In conclusion, our findings showed that centrally injected erythropoietin caused pressor and tachycardic response, an increase in respiratory frequency and volume in anaesthetized rats. Moreover intravenous injection of the highest dose of EPO used in the study caused no effect suggesting a central mechanism of action for the agent. Hence, one can hypothesize that erythropoietin may play a role in the central regulation of cardiovascular and respiratory system as a neuromodulator or neuromediator.
Asunto(s)
Presión Sanguínea/efectos de los fármacos , Eritropoyetina/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Neurotransmisores/farmacología , Mecánica Respiratoria/efectos de los fármacos , Anestesia , Animales , Sistema Nervioso Central/efectos de los fármacos , Eritropoyetina/fisiología , Femenino , Inyecciones Intravenosas , Inyecciones Intraventriculares , Neurotransmisores/fisiología , Ratas , Ratas Sprague-Dawley , Taquicardia/inducido químicamente , Volumen de Ventilación Pulmonar/efectos de los fármacosRESUMEN
The current study was designed to determine the cardiovascular effect of centrally administrated melittin, a phospholipase A2 (PLA2) activator, and the mediation of central thromboxane A2 (TXA2) and its receptors in normotensive conscious rats. Studies were performed in normotensive male Sprague Dawley rats injected intracerebroventricularly (i.c.v.) with melittin. Melittin (1.5, 3.0, 6.0 microg/5.0 microl; i.c.v.) caused dose- and time-dependent increases in mean arterial pressure (MAP) and decrease in heart rate (HR). Maximal effects were observed 5-10 min after 3.0 microg dose of melittin. In order to test the mediation of central TXA2 and its central receptors in the cardiovascular effect of melittin, the rats were pretreated with furegrelate (500.0 microg; i.c.v.), a TXA2 synthesis inhibitor, and SQ-29548 (8.0 microg; i.c.v.), a TXA2 receptor antagonist, 15 min prior to melittin (3.0 microg). Furegrelate or SQ-29548 partially inhibited the pressor effect and bradycardia elicited by melittin. In conclusion, our findings show that centrally administered melittin increases MAP and decreases HR in conscious rats. Moreover, according to our findings, central TXA2 and its receptors may in part mediate melittin-induced cardiovascular effects.