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1.
Eur Arch Otorhinolaryngol ; 279(12): 5905-5911, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35881191

RESUMEN

PURPOSE: The histological diagnosis after diagnostic thyroidectomy for indeterminate thyroid nodules is often non-malignant and some cancers detected are considered 'indolent'. The safety and effectiveness of conservative management in these patients are unclear. The aim of this study was to determine the safety of conservative management of indeterminate thyroid nodules and to explore association between clinical features and pathology in patients undergoing surgery. METHODS: This is a retrospective cohort study of patients presenting to a single centre over a 4-year period (2013-2016) with thyroid nodules that were considered indeterminate (thy3f in the UK RCPath classification) on cytology. Demographic data, ultrasound features, follow-up details (in those undergoing conservative management) and histology details (in those undergoing surgery) were collected. RESULTS: Of 164 patients that had Thy3f cytology, 34 were initially managed conservatively; however, 4 of these eventually had surgery (due to patient preference). No patient on conservative management had significant disease progression on ultrasound at a median (interquartile range) of 27 (16-40) months. Of the 134 patients that underwent surgery, 26 had thyroid malignancy. The BTA 'U' classification, gender and age (> 55) were not associated with malignancy in these nodules, but larger nodules (> 40 mm) were more likely to be malignant (p = 0.042). CONCLUSIONS: Conservative management of indeterminate (Thy3f or Bethesda stage IV) thyroid nodules is safe in the short term and may be indicated in selected cases after appropriate discussion of risks and benefits of surgery.


Asunto(s)
Neoplasias de la Tiroides , Nódulo Tiroideo , Humanos , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/cirugía , Estudios Retrospectivos , Tratamiento Conservador , Biopsia con Aguja Fina , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/cirugía
2.
IBRO Rep ; 8: 48-55, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32072069

RESUMEN

c-Jun N-terminal kinases (JNKs) are members of the mitogen-activated protein kinase (MAPK) family and are derived from three genes, Jnk1-3. These kinases are involved in cellular responses to homeostatic insults, such as inflammation and apoptosis. Furthermore, increased JNK expression and activation are associated with debilitating neurodegenerative diseases, including Alzheimer's and Parkinson's. We previously reported elevated levels of phosphorylated JNK (pJNK), indicative of JNK hyperactivation, in the CA1 hippocampus of chronically epileptic rats. We also showed that pharmacological inhibition of JNK activity reduced seizure frequency in a dose-dependent fashion (Tai TY et al., Neuroscience, 2017). Building on these observations, the objectives of this current study were to investigate the timeline of JNK activation during epileptogenesis, and to identify the JNK isoform(s) that undergo hyperactivation in the chronic epilepsy stage. Western blotting analysis of CA1 hippocampal homogenates showed JNK hyperactivation only during the chronic phase of epilepsy (6-9 weeks post-status epilepticus), and not in earlier stages of epileptogenesis (1 h, 1 day, and 1 week post-status epilepticus). After enrichment for pJNK by immunoprecipitation, we identified JNK2 as the only significantly hyperactivated JNK isoform, with expression of the 54 kDa pJNK2 variant elevated to a greater extent than the 46 kDa pJNK2 variant. Expression of the total amounts of both JNK2 variants (phosphorylated plus non-phosphorylated) was reduced in epilepsy, however, suggesting that activation of upstream phosphorylation pathways was responsible for JNK2 hyperactivation. Since our prior work demonstrated that pharmacological inhibition of JNK activation had an antiepileptic effect, JNK2 hyperactivation is therefore likely a pathological event that promotes seizure occurrences. This investigation provides evidence that JNK2 is selectively hyperactivated in epilepsy and thus may be a novel and selective antiepileptic target.

3.
Vet World ; 11(4): 542-548, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29805223

RESUMEN

AIM: This study aimed to evaluate the efficacy of Doublesynch and Estradoublesynch protocols on estrus induction, conception rates, plasma progesterone, protein, and cholesterol profile in anestrus Gir heifers. MATERIALS AND METHODS: In this study, 50 pubertal anestrus Gir heifers were selected from the field and farm conditions. The heifers were dewormed (injection ivermectin, 100 mg, s/c) and supplemented with minerals and vitamins (injection organic phosphorus 800 mg and injection Vitamin AD3E and Biotin 10 ml i/m) and multi-mineral bolus at 1 bolus daily for 7 days. The heifers were randomly divided into three groups: Doublesynch (n=20), Estradoublesynch (n=20), and control (n=10). The animals were monitored for estrus response, estrus interval, behavioral signs, and conception rates after induced/first, second, and third cycle post-treatment. Blood samples were obtained on day 0, day 9, day 12, and on day 12 post-artificial insemination (AI) for determination of plasma progesterone, protein, and cholesterol profile. RESULTS: The estrus response rate between Doublesynch and Estradoublesynch protocols was similar between treated heifers (85% and 95%). The interval from the second prostaglandin F2α (PGF2α) injection to estrus induction did not differ between the groups (63.87±4.19 vs. 58.27±3.83 h). The conception rates following induced estrus (20% vs. 30%), at the second cycle (23.07% vs. 16.66%), at the third cycle (22.22% vs. 30.00%), and the overall conception rate (45% and 55%) within 27.89±5.75 and 26.45±5.48 days were the same across the treatment groups. The mean plasma progesterone concentrations were significantly (p<0.01) higher on day 9 (second PGF2α injection) and day 12 post-AI compared to day 0 (first PGF2α injection) and the day of fixed-timed artificial insemination. The concentrations were also significantly (p<0.05) higher in conceived than non-conceived heifers on day 9 of treatment and day 12 post-AI in both the protocols. The mean plasma cholesterol concentrations were significantly higher during peak follicular and luteal phases compared to the initial anestrus phase in both the protocols. The values were also higher in non-conceived than conceived animals in both the protocols. The plasma protein profile was not influenced by the sampling days or conceived and non-conceived status. CONCLUSION: The results showed that both Doublesynch and Estradoublesynch protocols resulted in similar estrus induction and conception rates with modulation of plasma progesterone and cholesterol profile in anestrus Gir heifers.

4.
Vet World ; 10(3): 302-310, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28435192

RESUMEN

AIM: The aim of this study was to evaluate the influence of peripartum protein and minerals supplementation on plasma profile of steroid hormones, metabolites, and fertility in rural buffaloes. MATERIAL AND METHODS: A total of 85 advanced pregnant (~8 months) pluriparous buffaloes selected at farmers' doorstep in three tribal villages of Middle Gujarat were randomly divided into two groups, viz., control (n=45) and nutrients treatment (40). The buffaloes of treatment group (n=40), in addition to farmers feeding schedule/control, received daily 1.5 kg compound concentrate mixture (22% CP) and 50 g of chelated ASMM for 2 months each pre- and post-partum. Further, 15 buffaloes, each of control and treatment group, were injected parentrally (deep i/m) with 5 ml of micro-minerals (each ml containing Se, Zn, Cu and Mn at 5, 40, 15 and 10 mg, respectively), twice 2 months before and on the day of calving, keeping rest of the animals (control, n=30 and treatment, n=25) as controls. Blood sampling was done on days -60, -30, -15, 0, 15, 30, 45, and 60 peripartum for estimation of plasma progesterone and estradiol by standard RIA techniques and other metabolites using assay kits on biochemistry analyzer. The puerperal events and postpartum fertility were monitored through history and by fortnightly palpation per rectum till day 45 and then again at 120 days postpartum for both the groups and subgroups. RESULTS: The mean plasma progesterone concentrations in all groups declined significantly (p<0.05) from day 60 to day 15 prepartum, reached to the basal levels (<0.5 ng/ml) on the day of parturition, and subsequently, reduced nonsignificantly till day 15 postpartum and then showed a rising trend from day 30 to 60 postpartum with significantly higher values at day 45 and/or 60. The mean plasma estradiol values increased with approaching parturition and were at its peak on the day of calving (p<0.01). Thereafter, there was a rapid fall in the levels by day 15 and it remained low till day 45-60 postpartum. The blood glucose values showed an increasing trend with advancing gestation, reaching the highest on the day of calving, dropped significantly (p<0.01) within 15 days postpartum, and thereafter showed consistent values. The buffaloes supplemented with peripartum nutrients maintained significantly (p<0.05) higher blood glucose concentrations than the control during the peak lactation. The plasma protein levels varied significantly (p<0.05) between days within the group with the lowest values on the day of calving, as well as between groups with higher (p<0.05) values on day 30 and 60 postpartum in treated group. Micro-minerals injected did not reveal significant influence on steroid hormones, blood glucose, or plasma protein. The mean plasma total cholesterol was significantly lower (p<0.05) in treatment than the control group. The mean values in micro-minerals injected subgroup were higher than the non-injected control subgroup during postpartum phase. The mean plasma triglyceride values in the pregnant buffaloes under both the groups and subgroups gradually decreased as parturition approached with significantly lowest values on the day of calving. The values increased nonsignificantly by day 15 and then remained steady throughout postpartum period without influence of nutrient supplementation or micro-minerals injection. The incidence of retained fetal membranes (RFMs) was 5.00 and 13.33% in treatment and control groups, respectively, with placental expulsion time of 3.27±0.37 and 4.44±0.53 h (p>0.05). The micro-minerals injection appreciably reduced the incidence of RFMs and significantly (p<0.05) reduced the placental expulsion time over non-injected controls. In treatment group, the period for involution of uterus was significantly shorter (29.39±0.50 vs. 32.12±0.82 days, p<0.05), with early onset of first postpartum estrus (67.65±1.67 vs. 79.43±3.06 days, p<0.01), shorter service period (90.89±4.41 vs. 105.09±4.76 days, p<0.05) and higher conception rate (55.00 vs. 40.00%) than in control group. The micro-minerals injection apparently and/or significantly improved all these traits in both the groups. Thus, the postpartum reproductive performance was significantly improved in treated than control groups and subgroups. CONCLUSION: The results showed that nutrient supplementation in terms of high protein concentrate, ASMM and injection of sustained release micro-minerals (Se, Zn, Cu, and Mn) during transition period minutely altered the plasma steroid hormones and blood metabolites though it significantly improved the postpartum reproductive performance in buffaloes under field conditions.

5.
Vet World ; 8(11): 1310-6, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27047035

RESUMEN

AIM: To evaluate estrus induction response and fertility including plasma progesterone and biochemical profile following use of three standard hormonal protocols in anestrus crossbred cows. MATERIALS AND METHODS: The study was carried out on 40 true anestrus and 10 normal cyclic cows. 10 anestrus cows each were treated with standard intravaginal controlled internal drug release (CIDR) device, Ovsynch (GPG) protocol, and Norgestomet ear implant with fixed-time artificial insemination (FTAI). 10 anestrus cows were kept as untreated control while 10 cows exhibiting the first estrus within 90 days postpartum without any treatment served as normal cyclic control. Blood samples were obtained from treated cows on day 0, 7, 9 (AI) of treatment and day 21 post-AI, and from control groups on the day of AI and day 21 post-AI for estimation of plasma progesterone, protein, cholesterol, calcium, and inorganic phosphorus profile. RESULTS: The use of CIDR, Ovsynch, and Norgestomet ear implant protocols resulted in 100% estrus induction with conception rates at induced estrus of 60%, 50%, and 50%, and the overall of three cycles as 80%, 80%, and 70%. In untreated anestrus control (n=10), only three cows exhibited spontaneous estrus within 90 days of follow-up and conceived giving the first service and overall conception rates of 66.66% and 30.00%, respectively. In normal cyclic control (n=10), the conception rates at first and overall of three cycles were 50% and 80%. The overall mean plasma progesterone (P4) concentrations in anestrus cows studied on day 0 (initiation), 7 (prostaglandin injection and/or removal of implant), 9 (FTAI) of treatment and on day 21 post-AI revealed that the values on day 7 and 21 were significantly (p<0.01) higher than other two periods in all three groups. The concentrations were significantly (p<0.05) higher in conceived than non-conceived group on day 21 post-AI in CIDR (4.36±0.12 vs. 1.65±0.82 ng/ml) and Ovsynch (4.85±0.62 vs. 1.59±0.34 ng/ml), but not in Norgestomet ear implant (4.50±0.53 vs. 3.02±1.15 ng/ml) or normal cyclic group (5.39±0.67 vs. 3.13±0.37 ng/ml). The cholesterol and protein levels were significantly higher, but not the calcium and phosphorus, in normal cyclic control than in anestrus groups. The influence of treatment days and pregnancy status was not significant for any of the biochemical constituents in any of the groups. CONCLUSION: Ovsynch and/or CIDR synchronization protocol can be effectively used to improve fertility up to 80% in anestrus cows, as compared to 30% in anestrus control, combined with plasma progesterone to delineate the reproductive status before and after treatment.

6.
Vet World ; 8(2): 239-44, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27047080

RESUMEN

AIM: The aim was to compare commercially available soybean milk-based extenders, viz. Bioxcell(®) and Optixcell(®) (IMV, France) with standard Tris-citrate-fructose-egg yolk-glycerol (TFYG) extender for cryopreservation of buffalo semen. MATERIALS AND METHODS: Semen was collected twice a week in artificial vagina from six sexually mature, 4-6 years old, healthy breeding bulls of Surti buffalo breed. In all 48 qualifying ejaculates (8 per bull) having initial motility >70% were split into three equal aliquots and were diluted (at 34°C keeping 100×10(6) sperm ml(-1)) in TFYG, Bioxcell and Optixcell extenders. The French mini straws filled from each aliquot were gradually cooled to 4-5°C, equilibrated at 4°C for 4 h and frozen in liquid nitrogen 2 vapor using programmable biofreezer. Just before freezing (post-equilibration) and 24 h after frozen storage, the samples were evaluated for various sperm quality parameters using standard protocols. Frozen semen straws were thawed in a water bath at 37°C for 30 s. The post-thaw incubation survival (37°C for 1 h) was assessed through motility rating at 0, 30 and 60 min of incubation. RESULTS: The mean percentages of prefreeze sperms in TFYG, Bioxcell and Optixcell extenders in terms of progressive motility (69.48±0.37, 68.02±0.49, 70.94±0.38), viability (79.21±0.39, 77.38±0.48, 81.58±0.38), total abnormalities (7.90±0.14, 8.60±0.16, 7.08±0.15), intact acrosome (89.54± 0.18, 88.58±0.22, 90.52±0.21) and hypoosmotic swelling (HOS) reactivity (67.96±0.32, 65.65±0.42, 70.23±0.37) varied significantly (p<0.05) between extenders. Similar pattern of significant (p<0.05) variations between these extenders for post-thaw sperm progressive motility (47.71±0.79, 44.38±0.85, 49.90±0.90), viability (57.19±0.79, 53.85±0.84, 59.67±0.91), total abnormalities (12.33±0.17, 12.75±0.21, 11.27±0.18), intact acrosome (76.83±0.23, 75.90± 0.27, 78.50±0.25) and HOS reactivity (45.02±0.84, 42.31±0.82, 47.81±0.90) was also observed for TFYG, Bioxcell and Optixcell extenders. The recently launched improved soybean milk-based extender Optixcell excelled the older Bioxcell extender and even standard TFYG in respect of some of the sperm quality parameters. CONCLUSION: The advantages of soy lecithin-based bovine semen extenders over egg yolk regarding sanitary issues are unquestionable but still egg yolk-based semen extenders are widely used because of the cost factor and good in vivo fertility results.

7.
J Dairy Sci ; 95(5): 2381-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22541466

RESUMEN

Three experiments were conducted to determine the effect of endogenous progesterone (P4) on body temperature comparing lactating, pregnant with lactating, nonpregnant cows, and to study the effect of exogenous P4 administered via a controlled internal drug release (CIDR) insert on body temperature in lactating dairy cows. Body temperature was measured vaginally and rectally using temperature loggers and a digital thermometer, respectively. In experiment 1, 10 cyclic lactating cows (3 primiparous, 7 multiparous) and 10 lactating, pregnant cows (3 primiparous, 7 multiparous) were included. Vaginal temperatures and serum P4 concentrations were greater in pregnant cows (vaginal: 0.3±0.01°C; P4: 5.5±0.4 ng/mL) compared with nonpregnant cows. In experiment 2, estrous cycles of 14 postpartum healthy, cyclic, lactating cows (10 primiparous, 4 multiparous) were synchronized, and cows were assigned randomly to 1 of 2 treatments (CIDR-P4 or CIDR-blank). A temperature logger was inserted 1 d after ovulation using a P4-free CIDR (CIDR-blank) and a CIDR containing 1.38g of P4 (CIDR-P4) in the control (n=7) and the P4-treated group (n=7), respectively. On d 3 after P4 treatment, vaginal temperature was 0.3±0.03°C greater compared with that on d 1 and d 5. In experiment 3, 9 cyclic multiparous lactating cows were enrolled 1±1 d after confirmed ovulation and a temperature logger inserted. Two days later, a CIDR-P4 was inserted on top of the CIDR-blank. On d 5±1 and d 7±1, respectively, the CIDR-P4 and CIDR-blank with the temperature logger were removed. During the CIDR-P4 treatment (48h), vaginal temperature was 0.2±0.05°C and 0.1±0.05°C greater than during the pre- and post-treatment periods (48h), respectively. Serum P4 concentration peaked during CIDR-P4 treatment (2.2±0.8 ng/mL) and was greater than during the pre-treatment period (0.2±0.2 ng/mL) for 48h. An increase in vaginal temperature could be due to endogenous and exogenous P4. However, a correlation between serum P4 concentrations and body temperature did not exist. Further investigations are warranted to better understand the pathways of the thermogenic effect of P4 on body temperature.


Asunto(s)
Temperatura Corporal/efectos de los fármacos , Progesterona/farmacología , Animales , Temperatura Corporal/fisiología , Bovinos , Implantes de Medicamentos , Femenino , Lactancia/efectos de los fármacos , Lactancia/fisiología , Embarazo , Progesterona/administración & dosificación , Progesterona/sangre , Progesterona/fisiología
8.
Environ Monit Assess ; 184(11): 6507-12, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22083401

RESUMEN

Electromagnetic radiation emitted by cell phone towers is a form of environmental pollution and is a new health hazard, especially to children and patients. The present studies were taken to estimate the microwave/RF pollution by measuring radiation power densities near schools and hospitals of Chandigarh city in India. The cell phone radiations were measured using a handheld portable power density meter TES 593 and specific absorption rates were estimated from the measured values. These values of electromagnetic radiation in the environment were compared with the levels at which biological system of humans and animals starts getting affected. The values were also compared with the international exposure limits set by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The highest measured power density was 11.48 mW/m(2) which is 1,148% of the biological limit. The results indicated that the exposure levels in the city were below the ICNIRP limit, but much above the biological limit.


Asunto(s)
Radiación Electromagnética , Exposición a Riesgos Ambientales/estadística & datos numéricos , Dosis de Radiación , Contaminantes Radiactivos/análisis , Teléfono Celular/estadística & datos numéricos , Hospitales/estadística & datos numéricos , Humanos , India , Microondas , Monitoreo de Radiación , Instituciones Académicas/estadística & datos numéricos
9.
J Dairy Sci ; 94(5): 2368-73, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21524526

RESUMEN

The overall objective of this study was to study the influence of induced estrus on body temperature, comparing 5 distinct intervals around induced estrus and to determine the diurnal pattern from 4 ± 1 d before to 4 ± 1 d after induced estrus. Sixteen estrous cycles of 9 postpartum dairy cows were synchronized with 2 injections of PGF(2α), 10 d apart. After the second PGF(2α) injection on d 10, temperature loggers were inserted into the vaginal cavity for a 12 ± 1-d period. Two days later, a third dose of PGF(2α) was injected to induce estrus. After confirmation of a corpus luteum, loggers were removed on d 5 ± 1. Observation of estrus, rectal palpation, and ultrasound scanning to determine ovulation were carried out every 4 ± 1h, beginning at 12h after the third PGF(2α) injection. Blood samples from the vena coccygea mediana were collected twice daily from d 11 to 12 and every 4 ± 1h after the third PGF(2α) injection until ovulation. Vaginal temperature was recorded every 5 min and averaged to hourly means for the following 5 periods: 1) 48 h preceding the third PGF(2α) injection, 2) from the third PGF(2α) injection to first signs of estrus, 3) estrus to ovulation, 4) a 4-h interval in which ovulation occurred, and 5) a 96-h post-ovulation period. High body temperatures (39.0 ± 0.5 °C) and low progesterone (P4) concentrations (<0.5 ng/mL) were observed during estrus, whereas low body temperatures were observed from PGF(2α) injection to estrus (38.6 ± 0.3 °C) and around ovulation (38.5 ± 0.2 °C), respectively. An association between body temperature and serum P4 concentrations did not exist. However, P4 concentrations on d 11 and 12 were high (5.0 ± 1.5 ng/mL) and decreased (0.9 ± 0.2 ng/mL) after ovulation. Diurnal temperature rhythms were similar before and after estrus. Vaginal temperature before estrus (d 11 and 12) was slightly (0.1 °C) higher compared with the post-ovulation period.


Asunto(s)
Temperatura Corporal , Bovinos/fisiología , Sincronización del Estro/fisiología , Vagina/fisiología , Animales , Ritmo Circadiano/fisiología , Dinoprost/administración & dosificación , Sincronización del Estro/efectos de los fármacos , Femenino , Progesterona/sangre , Factores de Tiempo
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 69(4): 1178-82, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17706456

RESUMEN

The highly sensitive technique of spin-probe Electron Spin Resonance (ESR) has been used to study dynamics of carbon nanotubes. The ESR signals were recorded for the nitroxide free radical TEMPO in carbon nanotubes from 5 to 300 K. The onset of the fast dynamics of the probe molecule was indicated by appearance of a narrow triplet at 230 K. The ESR measurements were also done on TEMPO in methanol for the comparative studies in the same temperature range, and in the latter observations, no change in spectra was seen around 230 K. The results indicate the occurrence of a change in the dynamics of carbon nanotubes around this temperature.


Asunto(s)
Nanotubos de Carbono/química , Marcadores de Spin , Óxidos N-Cíclicos/química , Espectroscopía de Resonancia por Spin del Electrón , Metanol/química , Temperatura
11.
Theriogenology ; 38(3): 565-74, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16727159

RESUMEN

A total of 36 semen ejaculates, six from each of three Holstein-Friesian bulls and three Murrah buffalo bulls, were frozen in tris citric acid-fructose-egg-yolk-glycerol diluent after 1 hour of equilibration to study the effect of various cooling rates (15, 30, 60 and 120 minutes from 10 degrees to 5 degrees C vs a control sample cooled for 120 minutes from 28 degrees to 5 degrees C) and thawing temperatures (40 degrees C 60 seconds , 60 degrees C 15 seconds and 80 degrees C 5 seconds ) on prefreeze and post-thaw sperm motility. Sperm motility differed significantly (P < 0.01) between various cooling rates in both the Holstein-Friesian bull semen and the Murrah buffalo semen at prefreezing, immediately post-thawing, and after 1 hour of post-thaw incubation at 38 degrees C. Post-thaw sperm motility and survival at 38 degrees C were significantly (P<0.01) higher in Holstein-Friesian bulls at 60 degrees C and 80 degrees C than at 40 degrees C (39.79+/-2.46% and 38.15+/-2.18% Vs 35.16+/-2.19%, and 20.22+/-2.14% and 19.05+/-2.05% vs 14.83+/-1.64%, respectively). In Murrah buffalo bulls the recovery percentage and survival rate increased significantly (P<0.01) with the increase in temperature from 40 degrees C to 80 degrees C (41.72+/-2.45%, 47.45+/-2.09% and 51.61+/-2.06%; and 9.22+/-1.47%, 11.79+/-1.63% and 12.27+/-1.53%, respectively). Prefreeze motility did not differ between cattle and buffalo bulls (64.97+/-1.08% Vs 67.11+/-0.89%, respectively) but post-thaw motility was significantly (P<0.01) higher in the buffalo (46.93+/- 1.39% Vs 37.70+/-1.32%). While incubation survival was higher in the cattle (18.04+/-1.16% Vs 10.96+/-0.89%). A fast cooling rate was found to be detrimental for cattle spermatozoa, whereas the post-thaw buffalo sperm motility deteriorated very quickly at 38 degrees C. The influence of species-by-cooling rate interaction was significant (P<0.01) for post-thaw motility and survival rate, but the species-by-thawing or cooling-by-thawing interactions were not significant. These results suggest that a cooling rate of 2 hour either at 10 degrees C or 28 degrees C is essential for cattle semen. However, buffalo semen can be frozen successfully after 30 minutes of cooling at 10 degrees C. A thawing temperature of 60 degrees C yielded a higher sperm motility rate than 40 degrees C. Thus, our findings can be applied under tropical conditions for the successful freezing-thawing of bovine semen provided conception rates are not affected adversely.

12.
Theriogenology ; 34(5): 853-63, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16726888

RESUMEN

Forty-eight semen ejaculates from four Surti buffalo bulls were studied under split sample technique to establish the effects of initial semen quality and tris fructose yolk glycerol (TFYF), egg yolk citrate glycerol (EYCG) and lactose yolk glycerol (LYG) extenders on the freezability, fertility (based on 3412 AI) and extracellular release of spermatozoal enzymes pre and postfreezing. The overall mean activity of GOT, GPT, AKP, ACP and LDH enzymes in the postthaw seminal plasma increased significantly (P<0.01) above prefreeze levels, whereas sperm motility decreased. Freezability and the release of these enzymes were not influenced by the types of extenders used except for AKP release, which was significantly (P<0.01) lower in TFYG diluent. The pre and postfreeze sperm motility was significantly higher (P<0.01) and the leakage of GOT, AKP and ACP was lower in 36 semen samples with an initial motility above 70% than in the 12 samples in which initial motility was between 60 and 70%. The effects of interactions between motility groups, diluents and freezing periods were statistically nonsignificant for both freezability and leakage of all five enzymes. Fertility rate of frozen semen produced in TFYG diluent was significantly (P<0.05) higher (42.69%) than in the other diluents and was followed by that of EYCG (39.78%) and LYG (37.50%) with an overall mean of 40%. Sperm post-thaw motility had significantly (P<0.01) negative correlations with the release of enzymes: GOT (-0.948); GPT (-0.859); AKP (-0.673); ACP (-0.951) and LDH (-0.764). Fertility rates showed high negative correlations with the release of all five enzymes. Freezability was positively correlated with fertility (+0.405). Significant positive correlations were also observed for the release of GOT with that of GPT (+0.944); AKP (+0.574); ACP (+0.911) and LDH (+0.839): GPT with ACP (+0.795) and LDH (+0.870): and ACP with AKP (+0.725) and LDH (+0.577). These findings stressed the use of simple estimates of GOT and AKP leakage as markers for the assessment of freezability and fertility, and also the importance of initial good quality semen and the suitablity of extenders (TFYG) in the production of frozen buffalo bull semen for better fertility rates.

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