Određivanje optimalne koncentracije Minitube Equex paste za krioprezervaciju sjemena nerasta prema karakteristikama pokretljivosti sperme

Equex paste is a non-permeating cryoprotective agent (CPA) that improved post-thaw survival of spermatozoa during boar semen cryopreservation. However, Equex paste produced by Nova Chemical Sales Inc. (MA, USA) is not currently available. The aim of the present study was to determine the optimal concentration of Minitube Equex paste (Minitube, Tiefenbach, Germany) for boar semen cryopreservation in comparison with Nova Equex STM paste (control). Fifteen ejaculates from 12 mature boars were collected by the glove-hand method. Each ejaculate was aliquoted and cryopreserved in base freezing extender III as Tris-citrate egg yolk (TEY) extender plus 9.0% glycerol classified into four groups. Group I was the control and included only 1.5% Nova Equex STM paste. Groups II, III and IV were the experiment groups, and contained different concentrations of Minitube Equex paste (Group II: 1.5%; Group III: 1.7%; and Group IV: 1.9%) added to the freezing extender III. After freezing and thawing, sperm motility characteristics were evaluated by Sperm Class Analyzer® incubated at 37 °C for 0 (10 min), 1 and 2 h post-thawing. In Group IV after thawing at 0 h, rapid velocity and the velocity curved line were significantly higher than in Groups II and III (P < 0.05) but did not differ from Group I. Moreover, after thawing at 1 h, LIN (linearity) in Group IV was higher than in Group II (P < 0.05), but did not differ from the other groups. In conclusion, the most suitable concentration of Minitube Equex paste in the current protocol was 1.9% supplemented with 9.0% glycerol in TEY-based freezing extender III, based on the conformity between data from manual guides and the observed sperm motility characteristics results.Equex pasta je neprožimajuće kriozaštitno sredstvo (CPA) za koje je dobro poznato da poboljšava preživljavanje spermija nakon odmrzavanja tijekom krioprezervacije sjemena nerasta. Međutim, Equex pasta koju proizvodi tvrtka Nova Chemical Sales Inc. (MA, SAD) trenutno nije dostupna na tržištu. Cilj ove studije bio je odrediti optimalnu koncentraciju Minitube Equex paste (Minitube, Tiefenbach, Njemačka) za krioprezervaciju sjemena nerasta u usporedbi s Nova Equex STM pastom (kontrola). Prikupljeno je petnaest ejakulata 12 zrelih nerasta metodom manualne fiksacije penisa. Svaki ejakulat bio je raspodijeljen i krioprezerviran u osnovnom razrjeđivaču za duboko zamrzavanje III – razrjeđivač trinatrijev citrat s dodatkom žutanjka jajeta (TEY) plus 9,0 % glicerola, razvrstano u četiri skupine (tj. skupine I, II, III i IV). Skupina I: 1,5 % Nova Equex STM pasta (kontrola) i tri različite koncentracije Minitube Equex paste (Skupina II: 1,5 %; Skupina III: 1,7 %; i Skupina IV: 1,9 %) dodano je osnovnom razrjeđivaču za duboko zamrzavanje III. Nakon zamrzavanja i odmrzavanja, karakteristike pokretljivosti spermija procijenjene su pomoću analizatora sperme Sperm Class Analyzer® inkubirano na 37 °C, 0 (10 min), 1 i 2 h nakon odmrzavanja. U Skupini IV, 0 h nakon odmrzavanja, brzina i krivulja brzine bile su značajno više nego u Skupinama II i III (P < 0,05), ali se nisu razlikovale od Skupine I. Nadalje, 1 h nakon odmrzavanja, LIN (linearnost) u Skupini IV bila je veća nego u Skupini II (P < 0,05), ali se nije razlikovala od ostalih skupina. Zaključno, najprikladnija koncentracija Minitube Equex paste u ovom protokolu bila je 1,9 % uz dodatak 9,0 % glicerola u TEY razrjeđivaču za zamrzavanje III, zbog sukladnosti između podataka iz priručnika i zamijećenih rezultata karakteristika pokretljivosti spermija

Fertilization Rate and Number of Embryos on Day 2 after Intrauterine and Deep Intrauterine Insemination Using Frozen-Thawed Boar Semen in Multiparous Sows

The present study determines fertilization rate and number of embryos on Day 2 after intrauterine insemination (IUI) and deep intrauterine insemination (DIUI) using frozen-thawed (FT) boar semen in multiparous sows. Twelve crossbred Landrace × Yorkshire multiparous sows were included. The sows were inseminated at 24 h after oestrus detection and reinseminated every 12 h until ovulation took place. The inseminations were conducted using IUI with 2 × 109 FT sperm per dose (n = 6) and DIUI with 1 × 109 FT sperm per dose (n = 6). The sows were slaughtered at 45.1 ± 7.2 h after ovulation. Embryos and unfertilized oocytes were flushed from the oviducts. IUI yielded a better fertilization rate than DIUI (66.0% versus 31.0%, P < .001). The number of embryos was 13.5 ± 2.7 and 6.6 ± 3.2 embryos/sow in IUI and DIUI groups, respectively (P = .08). The proportion of sows having unilateral fertilization was higher in the DIUI (3/5) than the IUI group (1/6). In conclusion, IUI with at least 2 × 109 total number of FT boar spermatozoa is recommended

Usporedba razrijeđivača za duboko smrzavanje sjemena nerasta temeljenih na dodatku žutanjka jajeta i sojinog lecitina

This study investigated the effects of using egg yolk and/or lecithin combinations in semen extender on frozen-thawed boar sperm quality. A total of 19 ejaculates from 8 Duroc boars were included. Each ejaculate was aliquoted and cryopreserved in three different extenders containing only egg yolk (20.0%; group I), only lecithin (6.0%; group II) and a combination of egg yolk (10.0%) and lecithin (3.0%) (group III). Frozen-thawed sperm motility, motion characteristics, viability, acrosome integrity, membrane permeability and mitochondrial activity were evaluated using a computer assisted sperm analysis system, SYBR-14/ Ethidiumhomodimer-1, FITC-PNA, sHOST test and JC-1 staining. The frozen-thawed sperm motility in groups I and III did not differ significantly (P>0.05), though the combination of extenders was better than group II (P<0.05). Motion characteristics, including straight-line velocity (VSL), linearity (LIN) and wobble coefficient (WOB), were higher in groups I and III than in group II (P<0.05). Likewise, sperm viability, membrane permeability and mitochondrial activity were higher in groups I and III than in group II (P<0.05). In conclusion, the use of lecithin without egg yolk in cryopreserved boar semen extender impaired frozen- thawed sperm quality. Thus, using either 20.0% egg yolk or a combination of 10.0% egg yolk and 3.0% lecithin is recommended for cryopreserved boar semen extender.U ovom su radu istraživani učinci žutanjka jajeta i/ili lecitina u razjeđivačima sjemena na kakvoću smrznute-odmrznute sperme nerasta. Uključeno je ukupno 19 ejakulata od 8 nerasta pasmine Duroc. Svaki je ejakulat bio raspodijeljen i zamrznut u 3 različita razrijeđivača, koji su sadržavali dodatak žutanjka jajeta (20,0 %) (skupina I), lecitina (6,0 %) (skupina II) i kombinaciju žutanjka jajeta (10,0 %) i lecitin (3,0 %) (skupina III). Nakon odmrzavanja vrednovane su: pokretljivost spermija, karakteristike gibljivosti, vijabilnost, integritet akrosome, permeabilnost membrane spermija i aktivnost mitohondrija pomoću računalno podržanog sustava za analizu sperme (CASA), SYBR-14/ etidiumhomodimer-1, FITC-PNA, JC-1 bojenja i HOS testa. Po odmrzavanju, pokretljivost spermija u skupinama I i III nisu se značajno razlikovale (P>0,05), ali su oba razrijeđivača bili bolji od skupine II (P<0,05). Karakteristike gibljivosti, uključujući pravocrtnu brzinu (VSL), linearnost (LIN) i koeficijent kolebljivosti (WOB), bili su viši u skupinama I i III u odnosu na skupinu II (P<0,05). Isto tako, vijabilnost spermija, permeabilnost membrane i aktivnost mitohondrija bili su viši u skupinama I i III u odnosu na skupinu II (P<0,05). Zaključno, uporaba lecitina bez žutanjka jajeta u razrjeđivaču za krioprezervaciju sjemena nerasta pogoršala je kvalitete zamrznuto-odmrznutog sjemena. Stoga se preporučuje uporaba 20,0 % žutanjka jajeta ili kombinacije 10,0 % žutanjka jajeta i 3,0 % lecitina kao dodataka razrijeđivaču za duboko smrzavanje sjemena nerasta

Bacteriospermia and its antimicrobial resistance in relation to boar sperm quality during short-term storage with or without antibiotics in a tropical environment

BackgroundIn tropical environments, boar semen is prepared either from a boar on the same farm as the sow herd or collected in semen collection centers and then transported to other farms. Thus, the semen doses can be used for artificial insemination either immediately or preserved for 2-3 days. The present study investigated the bacteriospermia and its antimicrobial resistance in relation to boar sperm quality during short-term storage in semen extender with or without antibiotics in Thailand.M&MIn total, 20 Duroc ejaculates were collected. Each ejaculate was diluted in Beltsville Thawing Solution extender either with 0.25 g of gentamicin per liter (ANTIBIOTIC) or without gentamicin (NO-ANITIBIOTIC) to create semen doses containing 3,000 x 10(6) sperm/100 mL. These were stored at 17 degrees C for 4 days. Semen characteristics and total bacterial count (CFU per mL, log(10)) were measured after collection and during storage.ResultsSperm viability was decreased by 6.4% for every 1.0 log(10) increase in total bacterial count (p = 0.026) and Staphylococcus spp. were the most frequently isolated across ejaculates. Throughout the 4 days of storage, sperm motility, viability and acrosome integrity in the ANTIBIOTIC group were higher than those in the NO-ANTIBIOTIC group (p 0.05). On the last day of preservation, Globicatella sanguinis (57.2%), Delftia acidovorans (18.9%) and Micrococcus spp. (5.9%) remained as the top three most abundant contaminants in the semen with antibiotic.ConclusionOur findings contribute new insights toward reducing antibiotics as well as rational antibiotic use in the boar AI industry. The growth of bacteria was significantly greater only after 2 days of preservation in the semen without antibiotic. For semen doses diluted from highly viable ejaculates, it is possible to store for 2 days without any antibiotic supplementation. Moreover, bacterial counts increased at the end of storage in the presence of gentamycin, suggesting the loss of bacteriostatic properties of gentamicin to the growth of bacteria during storage

Optimal plate spacing for mixed convection from an array of vertical isothermal plates

International audienceNumerical simulations of mixed convection of air between vertical isothermal surfaces were conducted in order to determine the optimum spacing corresponding to the peak heat flux transferred from an array of isothermal, parallel plates cooled by mixed convection. Comparisons between approximate analytical solutions for natural and forced convection are first discussed. It is shown that the agreement is fairly good. From the computations carried out for aiding mixed convection by assuming a pressure drop at the outlet section rather than a constant flow rate, it is numerically predicted that the optimum spacing is smaller than those for pure natural or pure forced convection. This spacing is determined according to the pressure drop. As a sample, we considered an array of 10 cm -height, isothermal surfaces at temperature T-h = 340 K with air as the working fluid entering into the channels at T-0 = 300 K. The increases in heat flux corresponding to the optimal spacing are discussed for outlet pressure drops ranging from -0.1 Pa to -1 Pa. Such a range covers the entire laminar mixed convection regime for this specific application

Hybrid formulation and solution for transient conjugated conduction–external convection

This work presents a hybrid numerical–analytical solution for transient laminar forced convection over flat plates of non-negligible thickness, subjected to arbitrary time variations of applied wall heat flux at the fluid–solid interface. This conjugated conduction–convection problem is first reformulated through the employment of the coupled integral equations approach (CIEA) to simplify the heat conduction problem on the plate by averaging the related energy equation in the transversal direction. As a result, an improved lumped partial differential formulation for the transversally averaged wall temperature is obtained, while a third kind boundary condition is achieved for the fluid from the heat balance at the solid–fluid interface. From the available steady velocity distributions, a hybrid numerical–analytical solution based on the generalized integral transform technique (GITT), under its partial transformation mode, is then proposed, combined with the method of lines implemented in the Mathematica 5.2 routine NDSolve. The interface heat flux partitions and heat transfer coefficients are readily determined from the wall temperature distributions, as well as the temperature values at any desired point within the fluid. A few test cases for different materials and wall thicknesses are defined to allow for a physical interpretation of the wall participation effect in contrast with the simplified model without conjugation.Indisponível

Improvement of the frozen boar semen quality by docosahexaenoic acid (DHA) and L-cysteine supplementation

The aim of the present study was to investigate the effect of docosahexaenoic acid and L-cysteine supplementation on qualities of cryopreserved boar semen. A total of 30 ejaculates from 10 Yorkshire boars were included in the study. The semen was cryopreserved in lactose egg yolk base extender containing different concentrations of docosahexaenoic acid (fish oil) or/and L-cysteine : 0 mg and 0 mM (Control), 290 mg and 0 mM (Treatment I), 290 mg and 5 mM (Treatment II) and 290 mg and 10 mM (Treatment III). Post thawing semen qualities (sperm motility, motility patterns, sperm viability, acrosomal integrity, functional plasma membrane integrity and DNA damage) were assessed. The results show that sperm motility and sperm viability were significantly improved by supplementing of docosahexaenoic acid and/or L-cysteine, or their combination if compared to the control group (P &lt; 0.05). The improvement of sperm parameters after supplementation of docosahexaenoic acid or/and Lcysteine, or their combination was more pronounced in the poor freezability sperm rather than at the good one. In poor freezability sperm, the supplementation of docosahexaenoic acid and/or 10 mmol/l Lcysteine resulted with higher sperm motility (34.7 vs. 22.3%, P &lt; 0.001), sperm viability (45.0 vs. 28.1%, P &lt; 0.05) and acrosomal integrity (46.9 vs. 36.2%, P &lt; 0.05) if compared to the control. In conclusion, the supplementation of docosahexaenoic acid, alone or in combination with L-cysteine significantly enhanced the sperm motility, sperm viability and acrosomal integrity of boar sperm after cryopreservation

Postotak koncepcije nakon primjene Ovsynch protkola s točno određenim vremenom umjetnog osjemenjivanja s aplikacijom egzogenog progesterona u cikličnih mliječnih krava tijekom toplog i hladnog razdoblja godine

Progesterone plasma levels during the warm period of the year (summer) are more variable and this can induce a reduction in the fertility of dairy cows. Therefore, the aim of this study is to investigate the effect of the combined use of progesterone supplements with an Ovsynch and FTAI protocol on conception rates during the summer in cows. The data were compared with treatments carried out during the cold season (winter). In total, 120 cows underwent oestrus synchronization by using an Ovsynch and FTAI protocol. After this, one group of 60 cows received progesterone supplements and another group of 60 cows did not. In each group, 30 cows were treated during the summer and 30 cows were treated during the winter. All cows were pre-synchronized with PGF2α 25 days and 11 days before starting the Ovsynch protocol. The conception rate at days 30 and 40 post-insemination was not changed by the Ovsynch protocol being supplemented with progesterone. No interaction between progesterone supplementation and the season (winter or summer ) was observed (P=0.17). The results of the study indicate that in cyclic cows with a functional corpus luteum the supplementation of the Ovsynch- FTAI protocol with progesterone did not improve the conception rate during the warm or cold seasons.Koncentracije progesterona u plazmi u mliječnih krava tijekom toplog razdoblja godine (ljeto) više variraju što može prouzročiti njihovu smanjenu plodnost. Stoga je cilj ovoga rada bio istražiti učinak aplikacije egzogenog progesterona u ovsynch protokolu u kombinaciji s točno određenim vremenom umjetnog osjemenjivanja (TOVO) na postotak koncepcije u mliječnih krava tijekom ljetnog razdoblja. Podatci su bili uspoređeni s istom kombinacijom protokola tijekom hladnog razdoblja godine (zima). Ukupno je u 120 krava sinkroniziran estrus klasičnim ovsynch i TOVO protokolom. Nakon toga, u 60 krava je apliciran egzogeni progesteron, dok u ostalih 60 krava nije apliciran spomenuti pripravak. U svakoj je skupini 30 krava tretirano tijekom ljeta i 30 krava tijekom zimskog razdoblja. Sve su krave bile podvrgnute postupku presinkronizacije s PGF2α 25 dana i 11 dana prije početka ovsynch protokola. Aplikacija egzogenog progesterona u kombinaciji s ovsynch protokolom 30. i 40. dana nakon umjetnog osjemenjivanja nije utjecala na postotak koncepcije. Nije ustavljena značajna povezanost između dodatka egzogenog progesterona i godišnjeg doba (zima ili ljeto)(P=0.17). Rezultati ovog istraživanja pokazali su da aplikacijom egzogenog progesterona u kombinaciji s ovsynch-TOVUO protokolom nije poboljšao postotak koncepcije u krava s cikličnom aktivnosti jajnika (funkcionalno žuto tijelo) tijekom toplog ili hladnog dijela godine