| 1. |
- Al-Essawe, Essraa M, et al.
(författare)
-
Seminal plasma influences the fertilizing potential of cryopreserved stallion sperm
- 2018
-
Ingår i: Theriogenology. - : Elsevier BV. - 0093-691X .- 1879-3231. ; 115, s. 99-107
-
Tidskriftsartikel (refereegranskat)abstract
- Seminal plasma (SP) contains proteins that may influence cryosurvival and prevent capacitation-like changes due to freezing and thawing. The objective of this study was to investigate the effect of adding pooled SP from "good" (GF) or "bad" (BF) freezer stallions on sperm cells' fertilizing ability. "Good freezers" refers to stallions that usually produce ejaculates which can withstand cryopreservation, whilst "bad freezer" stallions produce ejaculates which cannot tolerate the freezing process. A heterologous zona binding assay with in vitro matured bovine oocytes was used to assess the binding ability of equine sperm cells as a possible alternative to artificial insemination trials. The effect of adding SP i) prior to cryopreservation; ii) after thawing of sperm cells selected by single layer centrifugation (SLC); iii) to capacitation medium, was evaluated. Adding SP from GE stallions prior to cryopreservation reduced the mean number of sperm cells bound to the zona pellucida (ZP) compared to control (P = 0.0003), SP-free sperm cells and group received SP from BF stallions (P < 0.0001 for both). After thawing SLC-selected sperm cells treated with 5% SP showed a decrease in binding ability compared with SP-free sperm cells (P < 0.0001). The binding affinity of sperm cells was higher in the group treated with SP from GF than with SP from BF stallions (P < 0.05). Prolonged exposure to SP impaired the ability of stallion sperm cells to undergo capacitation and bind to ZP, regardless of the source of SP (P < 0.0001). The response of equine sperm cells to SP is influenced by the ability of the sperm cells to withstand cryopreservation and is affected by the timing of exposure and the origin of SP. Customization of the protocol for individual stallions is recommended to optimize the effect. (C) 2018 Elsevier Inc. All rights reserved.
|
|
| 2. |
- Al-Makhzoomi, A., et al.
(författare)
-
Sperm morphology and fertility of progeny-tested AI dairy bulls in Sweden
- 2008
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 70:4, s. 682-691
-
Tidskriftsartikel (refereegranskat)abstract
- Use of bull semen with high levels of sperm abnormalities, reflecting genital dysfunction, is not recommended for artificial insemination (AI) since it would most likely lead to subfertility. Sperm quality, including sperm morphology, may deteriorate with increasing age of the bull thus becoming a source of concern when using older, progeny-tested AI bull sires. Although a relationship between sperm morphology and fertility after AI in progeny-tested bull sires has been reported, it is yet unclear which sperm abnormalities are most critical. This constituted the core aim of a 22-month long retrospective study in proven (aged 60-84 months at the start of the study) AI sires of the Swedish Red (SR, n = 8) and Swedish Holstein (SLB, n = 4) breeds where their semen (107 freezing batches in total, built by a single ejaculate (n = 3) or pooling two consecutive ejaculates (n = 104) collected at 1-3 months interval), were subjected to detailed morphological examinations on wet- and dry, stained smears. Attention was paid to between- and within-bull variations with regard to presence and level of sperm abnormalities. Sperm morphology differed significantly between sires and ejaculates, with 6/12 sires having ejaculates containing greater than 10% of morphologically deviating sperm head shapes, a commonly used threshold for young At bulls in Sweden. However, with the exception of pear-shaped or narrow-at-the-base anomalies, the mean values for individual defects were always within the limits expected for a normal bull sire, and were therefore considered acceptable. The percentage of morphologically normal spermatozoa was positively related to fertility, whose output differed significantly among bulls. Among sperm abnormalities, the proportion of morphologically deviating sperm head shapes were negatively correlated with fertility, pear-shaped sperm heads in particular. In conclusion, the relationship between sperm morphology and fertility after AI calls for frequent (2-3 months interval) detailed assessments of sperm morphology in AI stud bull sires. (c) 2008 Elsevier Inc. All rights reserved.
|
|
| 3. |
- Alminana, C, et al.
(författare)
-
Adjustments in IVF system for individual boars: Value of additives and time of sperm-oocyte co-incubation
- 2005
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 64:8, s. 1783-1796
-
Tidskriftsartikel (refereegranskat)abstract
- In vitro fertilization (IVF) in pigs is still considered sub-optimal, due to the variable occurrence of polyspermy, variability mainly related to sperm differences. The present study was conducted in an attempt to increase the efficiency of the in vitro production of porcine embryos by optimizing the in vitro fertilization (IVF) protocol for individual males, with regard to the composition of the fertilization medium (experiments 1 and 2) and the length of gamete co-incubation time (experiment 3). A total of 5943 COCs were in vitro matured (IVM) and inseminated with frozen-thawed spermatozoa froth 2 boars (A and B). Experiment 1 determined the effect of additives caffeine (2 mM), hyaluronic acid (HA; [0.5 mg/mL]) and adenosine (10 mu M), alone or in combination, to the IVF-medium during sperm-oocyte co-incubation. Experiment 2 tested the addition of various HA (0, 0.5, 1.0 and 1.5 mg/ml) and adenosine (0, 10, 20 and 40 mu M) concentrations in the fertilization medium; while experiment 3 investigated the effect of two periods of sperm-oocyte co-incubation (10 thin or 6h). In the case of 10 min sperm-oocyte co-incubation, oocytes with attaching spermatozoa were further cultured in IVF-medium containing no spermatozoa until the 6 h of insemination was completed. Presumptive zygotes were cultured in embryo culture medium for 1215 h to assess fertilization parameters. In experiment 1, only caffeine significantly influenced the outcome of fertilization, albeit being a clearly boar-dependent effect. In experiment 2, similar boar differences were seen for HA supplementation while presence of exogenous adenosine did not influence fertilization parameters in either boar. The results of experiment 3 demonstrated that a short co-incubation time significantly (P less than 0.001) increased penetration rate and mean number of spermatozoa per oocyte (74.9 +/- 3.9% versus 62.7 +/- 3.9% and 1.5 +/- 3.2 versus 1.3 +/- 3.5 for 10 min or 6 h, respectively), but reduced monospermy (P less than 0.001, 57.9 +/- 2.5% versus 70.0 +/- 2.8%) when boar A was used. However, such effects were not seen with boar B, in which sperm-oocyte co-incubation time did not affect the efficiency of fertilization. In view of the present results, a preliminary screening for each individual male is required to select optimal conditions for IVF. (c) 2005 Elsevier Inc. All rights reserved.
|
|
| 4. |
- Alvarez-Rodriguez, Manuel, et al.
(författare)
-
Effect of colloid (Androcoll-Bear, Percoll, and PureSperm) selection on the freezability of brown bear (Ursus arctos) sperm
- 2016
-
Ingår i: Theriogenology. - : ELSEVIER SCIENCE INC. - 0093-691X .- 1879-3231. ; 85:6, s. 1097-1105
-
Tidskriftsartikel (refereegranskat)abstract
- The development of a species-specific conservation protocol that involves artificial insemination with frozen semen needs to validate an effective methodology for freezing semen. Colloid centrifugation has been suggested and widely applied as an effective tool for selecting animal spermatozoa for artificial breeding. The objective of the present study was to compare different methods of centrifugation, single layer using Androcoll-Bear and Percoll and double layer using PureSperm 100 (in two different discontinuous gradients 40%-80% and 45%-90%), for the selection of fresh brown bear sperm samples. In the before freezing group, all selected samples showed a higher progressive motility and viability (except Percoll for motility 43.0 +/- 5.3 [P < 0.051); all colloids except PureSperm 45/90% rendered samples with fewer damaged acrosomes. In the after thawing group, all tested centrifugation colloids showed a good capacity to decrease the number of damaged acrosomes. Furthermore, PureSperm treatment (45/90%) resulted in an increase in apoptotic-like changes not only immediately after thawing but also after the incubation test, leading us to suggest that this gradient could induce some kind of deleterious effects on the sperm samples. On the other hand, PureSperm treatment (40/80%) yielded a quality preservation capacity similar to Androcoll-Bear in number of damaged acrosomes, different relative to the control (control, 5.3 +/- 0.6; PureSperm 80, 2.0 +/- 0.3; Androcoll, 2.1 +/- 0.9 [P < 0.051) but a decrease in the number of viable spermatozoa recovered after thawing relative to the control (control, 21.2 +/- 3.1; PureSperm 80, 13.7 +/- 2.7 [P < 0.051). In conclusion, Androcoll-Bear constitutes a useful tool for handling of brown bear ejaculates owing to its simple handling and procedure with a reliable sperm selection and freezability. This colloid yielded an improvement in several sperm parameters in brown bear frozen-thawed semen; the selected spermatozoa of fresh samples with this colloid showed a better resistance to freezing compared with the control sample not only for motility but also for viability. (C) 2016 Elsevier Inc. All rights reserved.
|
|
| 5. |
- Alvarez-Rodriguez, Manuel, et al.
(författare)
-
Exosomes in specific fractions of the boar ejaculate contain CD44: A marker for epididymosomes?
- 2019
-
Ingår i: Theriogenology. - : ELSEVIER SCIENCE INC. - 0093-691X .- 1879-3231. ; 140, s. 143-152
-
Tidskriftsartikel (refereegranskat)abstract
- Seminal plasma (SP) is a complex fluid containing proteins, peptides, enzymes, hormones as well as extracellular vesicles (EVs). The SP interacts with spermatozoa and the inner cell lining of the female genital tract, adsorbing proteins and exosomes that modulate sperm functions and female immune responsiveness. In the present study, boar sperm-free SP was studied using flow cytometry (FC) after membrane tetraspanins (CD9, CD63 and CD81) and membrane receptor CD44 marking of non-enriched (whole SP) or gradient fractions enriched through two-step discontinuous KBr-density-gradient ultracentrifugation, in whole ejaculate or in selected ejaculate fractions. The results, evaluated by transmission electron microscopy, confirmed the presence of exosomes in all fractions of the pig SP. Noteworthy, these pig SP-exosomes were CD44-bearing when analysed by FC, with bands detected by western blotting (WB) at the expected 85 kD size. The two-step discontinuous KBr-density-gradient ultracentrifugation enriched the population of exosomes in two specific gradient fractions, indicating exosomes (either prostasomes or epididymosomes) could be separated from low-density lipoprotein (LDL) but they co-sediment with the high-density lipoprotein (HDL)-bearing fraction. The findings pave for the selective isolation of exosomes in functional studies of their function when interacting with spermatozoa, the oocyte and/or the female genitalia, including hyaluronan-CD44 interplay. (C) 2019 Elsevier Inc. All rights reserved.
|
|
| 6. |
- Alvarez-Rodriguez, Manuel, et al.
(författare)
-
Quality of frozen-thawed semen in brown bear is not affected by timing of glycerol addition.
- 2011
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 75:8, s. 1561-1565
-
Tidskriftsartikel (refereegranskat)abstract
- We have tested several freezing protocols for brown bear semen, modifying the time when glycerol was added (before and after cooling to 5 °C). No differences were found among protocols, indicating a good tolerance of brown bear semen to glycerol. This finding indicates that freezing protocols for brown bear semen could be modified to fit practical solutions which would facilitate preparation of the seminal samples in the field with the addition of glycerol at ambient temperature.
|
|
| 7. |
- Alvarez-Rodríguez, Manuel, et al.
(författare)
-
The addition of heat shock protein HSPA8 to cryoprotective media improves the survival of brown bear (Ursus arctos) spermatozoa during chilling and after cryopreservation.
- 2013
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 79:3, s. 541-550
-
Tidskriftsartikel (refereegranskat)abstract
- The Cantabrian brown bear survives as a small remnant population in northern Spain and semen cryopreservation for future artificial insemination is one of the measures being implemented for conservation of this species. As part of this program we investigated the value of adding heat shock protein A8 (HSPA8) to media (N-[Tris(hydroxymethyl)methyl]-2-aminoethanesulfonic acid-TRIS-fructose with 20% egg yolk) used for chilling and cryopreserving the spermatozoa. Semen samples from eight brown bears were obtained by electroejaculation during the breeding season. In experiment 1, we tested three concentrations of HSPA8 (0.5, 1, and 5 μg/mL) to determine whether sperm motility (computer assisted sperm analysis system) and sperm survival could be improved during refrigeration (5 °C) up to 48 hours. Results showed that sperm viability (test with propidium iodide) was improved by the addition of 0.5 and 5 μg/mL HSPA8. In experiment 2, HSPA8 was added to the cryopreservation media (6% final glycerol concentration) before the freezing process. Though there were no differences in sperm viability immediately after thawing (analyses to 0 hours), plasma membrane permeability (test with YO-PRO-1) was significantly lower by the presence of HSPA8 (1 μg/mL) and acrosomal damage (test with peanut agglutinin-fluorescein isothiocyanate conjugate) was reduced by higher concentrations of HSPA8 (1 and 5 μg/mL) (analyses after thermal stress test incubating over 2 hours to 37 °C). In experiment 3, results of a simple progression test carried out through artificial mucus (hyaluronic acid 4 mg/mL) showed a significant decrease in the total number of sperm able to swim a distance of 0.5 to 2 cm through a capillary tube for all HSPA8-based extenders. Nevertheless, the distance traveled by the vanguard spermatozoa, which represent a highly motile subpopulation, was restored by the inclusion of 1 and 5 μg/mL HSPA8 in the cryopreservation media. Thus, the HSPA8 addition to extender improves the quality of brown bear (Ursus arctos) sperm during chilling (viability) and after cryopreservation (number of sperm with damaged acrosomes and "apoptotic-like" changes).
|
|
| 8. |
- Axner, Eva, et al.
(författare)
-
Collection of field reproductive data from carcasses of the female Eurasian lynx (Lynx lynx)
- 2013
-
Ingår i: Theriogenology. - : Elsevier BV. - 0093-691X .- 1879-3231. ; 80, s. 839-849
-
Tidskriftsartikel (refereegranskat)abstract
- Information about reproductive physiology in the Eurasian lynx (Lynx lynx) would generate knowledge that could be useful in the management of the Swedish lynx population based on the knowledge about their reproductive potential and population development. Age-related differences in ovulation and implantation rates would affect the reproductive output and the development of the population. The aims of this study were to evaluate a protocol for collection of reproductive data from carcasses by comparisons with published field data and to generate data about reproduction in the Swedish lynx. Reproductive organs from 120 females that were harvested between March 1 and April 9 from 2009 to 2011 were collected and evaluated macroscopically for placental scars. Females had their first estrus as yearlings but did not have their first litter until the next season. Pregnancy rates were lower in 2-year-old females than in females aged 3 to 7 years but did not differ significantly from females aged 8 to 13 years (54.5%, 95.6%, and 75.0%, respectively). CL from the present season were morphologically distinctly different from luteal bodies from previous cycles (LBPC). All females >= 3 years had macroscopically visible LBPC, whereas only 67% of 22 to 23 months old females had one to three LBPC and no females <1 year of age had LBPC. Females aged 34 to 35 months had up to eight LPBC, whereas the highest number of LBPC counted in females >= 3 years of age was 11. These data would be in agreement with only one estrus per season and LBPC from at least three previous reproductive seasons in older females. The number of LBPC was significantly correlated with the weight of the ovaries r(s) = 0.648, P < 0.001) and the age of the animals (r(s) = 0.572, P < 0.001). Uterine weight differed significantly with the stage of the reproductive cycle and was highest for mature females in the luteal phase of the cycle. The estrous period, defined as occurrence of ovarian follicles lasted from March 5 to April 1 in this material. In conclusion, this study confirms that useful information about lynx reproduction can be collected from reproductive organs retrieved after the death of the animals. Continuous monitoring of lynx reproductive organs would therefore make a valuable contribution to collection of field data, gathering information that can be useful for the management of lynx populations and potentially for the lynx as an indicator of environmental disturbances. (C) 2013 Elsevier Inc. All rights reserved.
|
|
| 9. |
- Axner, Eva, et al.
(författare)
-
Concentrations of anti-Müllerian hormone in the domestic cat. Relation with spay or neuter status and serum estradiol
- 2015
-
Ingår i: Theriogenology. - : Elsevier BV. - 0093-691X .- 1879-3231. ; 83, s. 817-821
-
Tidskriftsartikel (refereegranskat)abstract
- Female cats with unknown history can be diagnosed as spayed or intact with a GnRH-stimulation test or an LH test independent of the stage in the estrous cycle. However, although most females are correctly diagnosed with the LH test, the sensitivity and specificity are not 100%. The GnRH-stimulation test, although reliable, requires an injection of buserelin 2 hours before the blood sample is collected. Granulosa cells are the only cell type that produces anti-Mullerian hormone (AMH) in females, whereas Sertoli cells produce AMH in males. Anti-Mullerian hormone has been linked to spay status in dogs and cats and to ovarian and testicular pathology and fertility in different species. Our aim was to evaluate serum AMH concentrations in spayed female cats and in intact female cats of known age and reproductive stage (inactive ovaries or luteal phase). In addition, our aim was to compare serum AMH concentrations in intact and neutered male cats. We analyzed serum AMH concentrations in 15 spayed and 16 intact females and in 15 intact and 12 neutered male cats. Serum AMH was below the lowest standard point (<0.14 ng/mL) in all spayed females and neutered males, ranged between 1.3 and 19.0 ng/mL in the intact females and between 4.8 and 813 ng/mL in intact males. Thus, the AMH test had 100% sensitivity and specificity to diagnose the presence or absence of ovaries and testes in this study. In addition, in contrast to serum estradiol, serum AMH was not affected by buserelin stimulation (P = 0.459). Serum AMH was not correlated with serum estradiol before (r(s) = -0.188, P = 0.519) or after (r(s) = 0.335, P = 0.242) buserelin stimulation in the intact females. Four 6-month-old intact cats (two females and two males) had the highest AMH concentrations which in the females might represent a prepubertal peak previously described in other species and in males is likely due to high concentrations before puberty. In conclusion, we found that the AMH Gen II ELISA is reliable for diagnosing spay and neuter status of cats and that the domestic cat might be an interesting model for studies on AMH dynamics. (C) 2015 Elsevier Inc. All rights reserved.
|
|
| 10. |
- Axner, Eva, et al.
(författare)
-
Macroscopic and microscopic evaluation of Eurasian lynx (Lynx lynx) female tubular reproductive organs in relation to ovarian structures
- 2015
-
Ingår i: Theriogenology. - : Elsevier BV. - 0093-691X .- 1879-3231. ; 84, s. 710-715
-
Tidskriftsartikel (refereegranskat)abstract
- Although monitoring wild animals in the field is essential for estimations of population size and development, there are pitfalls associated with field monitoring. In addition, some detailed data about reproductive physiology can be difficult to obtain in wild live animals. Studying reproductive organs from the Eurasian lynx killed at hunting or found dead could be used as a valuable addition to other field data. We evaluated reproductive organs from 39 Eurasian lynx females (Lynx lynx) killed in Sweden during the hunting seasons in 2009, 2010, and 2011. According to notes on ovarian structures, the animals were categorized as being in one of four different reproductive stages: juvenile (n = 10), follicular stage (n = 8), luteal stage (n = 11), and anestrus (n = 10). Corpora lutea were classified as fresh CL from the present season or as luteal bodies from previous cycles. Microscopic evaluations were blindly coded while the outer measurements of the vagina and uterus were taken at the time of organ retrieval. The width of the endometrium, myometrium, outer width of the uterine horns, and the diameter of the vagina differed significantly with the reproductive stage (P < 0.001) and were largest in the follicular and luteal phases. The number of endometrial glands evaluated blindly coded on a subjective scale was significantly associated with the reproductive stage (P < 0.0001) and was significantly higher in the luteal phase than that in any other reproductive stages (P < 0.05). Cornification of the vaginal epithelium was only observed in females in the follicular stage or in females with signs of a recent ovulation. In conclusion, both macroscopic and histologic measurements are useful for a correct classification of the reproductive stage when evaluating reproductive organs in the Eurasian lynx killed during the hunting season. Routine evaluation of reproductive organs has a potential to be a useful additional tool to field studies of live lynx to monitor their reproduction. (C) 2015 Elsevier Inc. All rights reserved.
|
|
| 11. |
- Ballester, J., et al.
(författare)
-
Post-thaw viability of bull AI-doses with low-sperm numbers
- 2007
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 68:6, s. 934-943
-
Tidskriftsartikel (refereegranskat)abstract
- Use of AI-doses containing low-sperm numbers are increasingly been used to optimise use of elite bulls as well as to accommodate an eventual wider application of sex-sorted semen. Since spermatozoa might, however, suffer from high extension rates, thus compromising fertility, this study evaluated the post-thaw sperm quality of semen from commercial progeny-tested, high-ranked AI-sires whose semen was within acceptable limits of normality, frozen in a split-design to 15 (control, 15M) or 2 x 106 total spermatozoa (treatment, 2M) per straw. Assessment post-thaw included computer-evaluated sperm motility (CASA), membrane integrity (SYBR-14/PI), membrane stability (Annexin-V/Pl), acrosome integrity (Carboxy-SNARF-1/PI/ FITC-PSA), and chromatin integrity (AO of in situ acid-induced DNA denaturation). High extension did not affect the proportions of linearly motile spermatozoa, of membrane integrity or stability nor chromatin integrity, immediately post-thaw. However, high extension clearly affected linear sperm motility following incubation at 38 degrees C for 30 min, sperm viability when assessed by SNARF and, particularly, acrosome integrity of the otherwise viable spermatozoa. Individual sire variation was evident. Fertility was preliminarily evaluated for one of the less affected bulls in a blind field trial. A total of 109 dairy cows were randomly inseminated with 15M or 2M-straws without differences in pregnancy rate between them (47% versus 43%). This similarity in fertility rates, confirmed the in vitro methods used were appropriate for identifying cryosurvival and further suggested the site of sperm deposition was not crucial for the fertility of low-sperm AI-numbers for this particular sire. However, the inter-bull variation seen calls for caution when cryopreserving low concentrations of bull spermatozoa with conventional freezing protocols. (C) 2007 Elsevier Inc. All rights reserved.
|
|
| 12. |
- Barranco, Isabel, et al.
(författare)
-
Levels of activity of superoxide dismutase in seminal plasma do not predict fertility of pig AI-semen doses
- 2019
-
Ingår i: Theriogenology. - : ELSEVIER SCIENCE INC. - 0093-691X .- 1879-3231. ; 140, s. 18-24
-
Tidskriftsartikel (refereegranskat)abstract
- Superoxide dismutase (SOD) is a major antioxidant enzyme in boar seminal plasma (SP). This study evaluated how SP-SOD affected sperm attributes when semen of boars of various breeds, included in commercial artificial insemination (Al)-programs, was extended and liquid-stored at 17 degrees C for AI; as well as their in vivo fertility (farrowing rate and litter size of 10,952 AI-sows). SP-SOD-activity was assessed in 311 ejaculates (100 boars) while sperm motility (by CASA), viability and intracellular H2O2 generation in viable spermatozoa (by flow cytometry) were measured at 0 and 72 h of liquid storage. SP-SOD activity was not affected by breed but differed (P amp;lt; 0.001) between boars (n = 50), ranging from 1.16 +/- 0.11 to 7.02 +/- 0.75 IU/mL. Semen Al-doses (n =44) hierarchically grouped (P amp;lt; 0.001) with low SP-SOD activity showed lower (P amp;lt; 0.05) sperm motility and intracellular H2O2 at 72 h of liquid storage. Fertility did not differ between AI-boars (n = 39) hierarchically grouped (P amp;lt; 0.001) with high or low SP-SOD activity. In conclusion, SP-SOD activity is boar dependent and positively related with sperm functionality of liquid stored semen AI-doses. However, this positive effect is not reflected on in vivo fertility post-AI. (C) 2019 Elsevier Inc. All rights reserved.
|
|
| 13. |
- Bergström, Annika, et al.
(författare)
-
Hormonal concentrations in bitches with primary uterine inertia
- 2010
-
Ingår i: Theriogenology. - : Elsevier BV. - 0093-691X .- 1879-3231. ; 73, s. 1068-1075
-
Tidskriftsartikel (refereegranskat)abstract
- Normal labor is accompanied by sequential changes in blood concentrations of prostaglandin F2 alpha (measured as 15-ketodihydro-PGF2 alpha = PGFM). progesterone, estradiol, oxytocin, vasopressin, and of elevated cortisol levels The aim of this study was to investigate hormone concentrations in dogs diagnosed with primary uterine inertia before and during treatment by cesarian section. The hypothesis was the dogs would have abnormally low plasma concentrations in one or several of the hormones involved in parturition The study comprised seven bitches with total primary uterine inertia (dystocia group) treated with cesarian section and SIX healthy bitches (control group) subjected to planned cesarean section Blood samples were taken before anesthesia, before surgery started, on delivery of the first puppy and on delivery of the last puppy The progesterone PGFM ratio in plasma was higher in the dystocia group than in the control group. but the serum estradiol concentration did not differ between groups The plasma concentrations of oxytocin and vasopressin increased in both groups when the first puppies were delivered, but both hormones were more elevated in the control group than in the dystocia group on delivery of the last puppies The plasma cortisol concentration increased to the same level in both groups In conclusion, the ratio between progesterone and PGFM was higher and the oxytocin and vasopressin concentrations lower in the dystocia clogs than in the control dogs The findings indicate that these hormones are involved in the pathophysiology of total primary uterine inertia in bitches (C) 2010 Elsevier Inc. All rights reserved
|
|
| 14. |
- Bolarin, A, et al.
(författare)
-
Dissimilarities in sows ovarian status at the insemination time could explain differences in fertility between farms when frozen-thawed semen is used
- 2006
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 65:3, s. 669-680
-
Tidskriftsartikel (refereegranskat)abstract
- Deep intrauterine insemination (DUI) offers a suitable alternative for the commercial use of frozen-thawed boar semen. The present study evaluated how the ovarian status at DUIs of frozen-thawed spermatozoa. (1 x 10(9) spz/dose, two DUls, 30-31 and 36-37 h after detection of oestrus) in 179 sows would explain differences in fertility between two farms with similar, but not equal, reproductive management (experiment 1). A further experiment investigated whether an increase in sperm number per AI-dose (1 versus 2 x 10(9) spz/dose, two DUls, 30-31 and 36-37 h after detection of oestrus, on 228 sows) could minimize this effect (experiment 2). Ovaries were checked by transrectal ultrasonography at the time of DUI and sows were classified into three categories: F-: ovarian pre-ovulatory follicles were visible during two examinations; O-: ovulation visible during one examination; and C-sows: corpora hemorragica visible during the two examinations. Overall farrowing rates differed (P less than 0.01) between farms (70.1 versus 51.2%, farms A and B, respectively). Distribution of sows among ultrasonography categories also differed (P less than 0.05) between farms (17.5, 72.2 and 10.3% were classified as F, O- and C-sows in farm A, versus 40.2, 29.3 and 30.5% in farm B). Nevertheless, farrowing rates and litter sizes within categories did not vary between farms (P greater than 0.05). In addition, a two-fold increase in the number of spermatozoa per DUI improved (P less than 0.05) fertility in F- and C-sows, but not in O-sows. In conclusion, the interval DUI-to-ovulation provides a major explanation for fertility differences between farms when frozen-thawed spermatozoa are used. (c) 2005 Elsevier Inc. All rights reserved.
|
|
| 15. |
- Cajas, Yulia N., et al.
(författare)
-
Nobiletin as a novel agent to enhance porcine in vitro embryo development and quality
- 2024
-
Ingår i: Theriogenology. - : ELSEVIER SCIENCE INC. - 0093-691X .- 1879-3231. ; 223, s. 36-46
-
Tidskriftsartikel (refereegranskat)abstract
- In vitro embryo production (IVP) is of great importance to the porcine industry, as well as for basic research and biomedical applications. Despite the large efforts made in laboratories worldwide to address suboptimal culture conditions, porcine IVP remains inefficient. Nobiletin (Nob, 5,6,7,8,3 ' ,4 ' hexamethoxyflavone) supplementation to in vitro culture (IVC) medium, enhances in vitro embryo development in various species. However, its impact on the quality and developmental capacity of in vitro-produced pig embryos is yet to be established. This study evaluated the effects of different concentrations (2.5 and 5 mu M) of Nob during the early culture of in vitro -pro- duced pig embryos on embryo developmental competence, mitochondrial activity, lipid content, intracellular Reactive Oxygen Species (ROS) and Glutathione (GSH) content, Total Cell Number (TCN) per blastocyst, and expression of genes related to embryo development, quality and oxidative stress. Embryos cultured in medium without Nob supplementation and in medium supplemented with 0.01 % dimethyl sulfoxide (DMSO-vehicle for Nob) constituted the Control and DMSO groups, respectively. Embryo development rates were evaluated on Days 2, 6 and 7 of IVC. Additionally, a representative group of embryos was selected to assess mitochondrial activity, lipid, ROS and GSH content (on Days 2 and 6 of IVC), TCN assessment and gene expression analyses (on Day 6 of IVC). No significant differences were observed in any of the parameters evaluated on Day 2 of IVC. In contrast, embryos cultured under the presence of Nob 2.5 showed higher developmental rates on Days 6 and 7 of IVC. In addition, Day 6 embryos showed increased mitochondrial activity, with decreased levels of ROS and GSH in the Nob 2.5 group compared to the other groups. Both Nob 2.5 and Nob 5 embryos showed higher TCN compared to the Control and DMSO groups. Furthermore, Nob 2.5 and Nob 5 upregulated the expression of Superoxide dismutase type 1 (SOD1) and Glucose-6-phosphate dehydrogenase ( G6PDH) genes, which could help to counteract oxidative stress during IVC. In conclusion, the addition of Nob during the first 48 h of IVC increased porcine embryo development rates and enhanced their quality, including the upregulation of relevant genes that potentially improved the overall efficiency of the IVP system.
|
|
| 16. |
- Cambra, J. M., et al.
(författare)
-
The cytokine platelet factor 4 successfully replaces bovine serum albumin for the in vitro culture of porcine embryos
- 2020
-
Ingår i: Theriogenology. - : ELSEVIER SCIENCE INC. - 0093-691X .- 1879-3231. ; 148, s. 201-207
-
Tidskriftsartikel (refereegranskat)abstract
- The cytokine platelet factor 4 (PF4) enhances differentiation and cell viability of different stem cells lines in vitro. This study investigated whether PF4 addition to customary pig embryo semi-defined culture media can improve their developmental outcome (Experiment 1) and ultimately replace the need for bovine serum albumin (BSA, Experiment 2). Experiment 1 added PF4 (100-1000 ng/mL, 0 = control) to NCSU-23 with 0.4 mg/mL BSA culturing 3430 presumptive zygotes. Experiment 2 added PF4 (100 -1000 ng/mL, 0 = Control-PVA) to a BSA-free medium (NCSU-23 with 0.3 mg/mL PVA) culturing 3820 presumptive zygotes. Zygote culture in NCSU-23 with 0.4 mg/mL BSA was used as overall control. All groups of Experiment 1 displayed similar rates of day 2-cleavage (range: 65.0 +/- 10.9 to 70.0 +/- 5.8%); of day 7-blastocyst rates (range: 46.6 +/- 10.0 to 56.4 +/- 8.2%) and of total day 7-blastocyst efficiency (range: 32.3 +/- 8.3 to 37.2 +/- 7.3%). Addition of PF4 did not affect total cell numbers of day 7 blastocysts (range: 44.1 +/- 23.2 to 50.5 +/- 26.4). In Experiment 2, PF4 accelerated embryo development, increasing (P < 0.01) blastocyst yield compared to 0-PF4, and blastocyst formation by day 5 adding PF4 100-500 ng/mL (range: 29.9 +/- 7.8 to 31.8 +/- 5.5%; P < 0.05) compared with BSA-control (17.2 +/- 8.2%) and PF4 1000 ng/mL (15.5 +/- 7.9%); showing similar blastocyst rates (range: 42.0 +/- 11.5 to 49.3 +/- 10.0%), total efficiency (28.0 +/- 8.2 to 32.3 +/- 7.1%) total cell numbers (range: 42.6 +/- 19.3 to 45.7 +/- 23.9) as BSA-controls. In conclusion, although PF4 did not show additive improvement under usual semi-defined, BSA-supplemented embryo media, it successfully replaced BSA sustaining porcine blastocyst production in chemically defined conditions. (C) 2019 Elsevier Inc. All rights reserved.
|
|
| 17. |
- Chatdarong, Kaywalee, et al.
(författare)
-
The development of cat testicular sperm cryopreservation protocols: Effects of tissue fragments or sperm cell suspension
- 2016
-
Ingår i: Theriogenology. - : Elsevier BV. - 0093-691X .- 1879-3231. ; 85, s. 200-206
-
Tidskriftsartikel (refereegranskat)abstract
- In endangered animals that have been found dead or sterilized for medical reasons, testis isthe ultimate source of haploid DNA or sperm. Thus, preservation of testicular sperm maybe performed to rescue their genetics. The aim of this study was to evaluate protocols fortesticular sperm freezing: as tissue fragments or cell suspension in domestic cats as amodel. A pair of testes from each cat (n ¼ 9) were cut into eight equal pieces. Fourrandomly selected pieces were cryopreserved as: (1) tissue pieces using two-step freezing;(2) tissue pieces using a slow passive cooling device (CoolCell); (3) sperm suspension aftersingle-layer centrifugation (SLC) through colloids; and (4) sperm suspension without beingprocessed through SLC. A testicular piece from each cat served as fresh control. Testicularsperm membrane and DNA integrity were evaluated before, and after, the cryopreservationprocess. In addition, spermatogenic cell types (testicular sperm, spermatogonia, spermatocyte,and spermatid) present in the suspension samples were counted before andafter SLC. The results found that testicular sperm membrane integrity in the suspensionafter SLC process was higher than that in the fragment form neither using the two-step norCoolCell freezing, both before and after freezing (before freezing: 92.3 3.4 vs. 81 4.5and 80.0 7.0; after freezing: 84.5 4.6 vs. 71.2 12 and 76.2 4.6; P 0.05). Testicularsperm DNA integrity was, however, not different among groups. Furthermore, the samplesprocessed through the SLC had higher ration of sperm cells: other spermatogenic cells thanthose were not processed through the SLC (88.9 3.8 vs. 30 7.9; P 0.05). In summary,testicular sperm cryopreserved as a minced suspension is considered suitable in terms ofpreventing sperm membrane integrity, and SLC is considered a selection tool for enrichinghaploid sperm cells from castrated or postmortem cats.
|
|
| 18. |
- Cox, J.F., et al.
(författare)
-
Computer-assisted analysis of sperm motion in goats and its relationship with sperm migration in cervical mucus
- 2006
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 66:4, s. 860-867
-
Tidskriftsartikel (refereegranskat)abstract
- In vitro sperm migration in cervical mucus relates to sperm concentration at the utero-tubal junction and to in vivo fertilization performance in goats. The present study aimed to characterize, using Computer-Assisted Sperm Analysis (CASA), motility patterns depicted by buck sperm and their relation to the migration efficiency in homologous (goat) and heterologous (heifer) cervical mucus in vitro. Semen was collected from 23 sexually mature bucks from three breeds by artificial vagina and sperm were assessed for motility parameters with a Hobson Sperm analyzer following extension in Sperm Analysis Medium (SAM). To study the relationship between kinematics parameters and the ability of sperm to migrate in cervical mucus, in a first experiment, motility performance of buck sperm suspended in SAM was compared against seminal plasma. In a second experiment, kinematics parameters of sperm were characterized. In a third experiment, bucks with sperm that differed in specific motion parameters were compared for the ability of their sperm to migrate through goat and bovine cervical mucus collected at estrus. In a fourth experiment, ejaculates that were compared in their migration ability and were assessed simultaneously for their motility parameters. Overall, sperm suspended in SAM medium had better velocity and similar linearity and lateral head displacement than those suspended in seminal plasma; furthermore, caprine sperm swam relatively fast (relative to bovine and ovine sperm), following a very linear trajectory. Under the conditions used, velocity parameters, linearity and lateral head displacement seemed to be related to sperm migration efficiency in homologous mucus but not in bovine cervical mucus. (c) 2006 Elsevier Inc. All rights reserved.
|
|
| 19. |
- Cuello, C., et al.
(författare)
-
Vitrification of in vitro cultured porcine two-to-four cell embryos
- 2007
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 68:2, s. 258-264
-
Tidskriftsartikel (refereegranskat)abstract
- The objective of this experiment was to evaluate the effect of a 5-day period of in vitro culture of two-to-four cell porcine embryos up to the blastocyst stage on their ability to survive vitrification and warming. In order to increase the cooling rate, superfine open pulled straws and Vit-Master (R) technology were used for vitrification. Two-to-four cell embryos were collected from weaned sows (n = 11) on day 2 (DO = onset of estrus). Some embryos (N = 63) were vitrified within 3 It after collection, warmed and cultured for 120 h (Group V2). Additionally, 81 two-to-four cell embryos were cultured for 96 It in order to obtain blastocysts; these were then vitrified, warmed and cultured for 24 h (Group VB; N = 65). The remaining two-to-four cell embryos were used as controls and thus not vitrified (control embryos; N = 70) but were cultured in vitro for 120 h. The V2, VB and control embryos were evaluated for their developmental progression and morphology during culture. All embryos (V2, VB and controls) were fixed on the same day of development in order to assess the total number of blastomeres. The survival and blastocyst formation rates obtained from V2 embryos were very poor (9.6 +/- 0.7% and 3.2 +/- 0.5%, respectively). The survival and hatching rates of VB embryos (75.0 +/- 0.69% and 33.6 +/- 0.13%) were lower (p less than 0.001) than those obtained with control embryos (89.1 +/- 0.8% and 47.5 +/- 0.12%). Hatched VB embryos had a lower (p less than 0.01) total cell number than hatched control embryos (70.3 +/- 4.5 versus 90.6 +/- 3.2, respectively). There was no difference between expanded VB and control blastocysts. In conclusion, blastocysts derived from in vitro culture of two-to-four cell pig embryos could be successfully vitrified using SOPS straws and Vit-Master (R). (c) 2007 Elsevier Inc. All rights reserved.
|
|
| 20. |
- de Paz, Paulino, et al.
(författare)
-
The relationship between ram sperm head morphometry and fertility depends on the procedures of acquisition and analysis used.
- 2011
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 76:7, s. 1313-1325
-
Tidskriftsartikel (refereegranskat)abstract
- Sperm head morphometry is a parameter in the evaluation of semen that has been associated with fertility in two ways: comparing morphometric measures between predefined groups of fertility; or analyzing morphometric data by multivariate techniques to identify cell populations. We analyzed the morphometry of ram sperm head by three procedures and checked its relationship with male fertility. A Computer-Aided Sperm Morphometric Assessment procedure (CASMA), an image analysis software (NIS-Elements) in combination with an optical microscope (MO-NIS) and this image analysis software in combination with a scanning electron microscope (SEM-NIS) were used. Eight morphometric parameters were assessed: length, width, area, perimeter, ellipticity, form factor, elongation and regularity. We observed significant differences between the morphometric data of sperm head obtained with three study procedures. The CASMA procedure shows the highest values for all parameters and the SEM-NIS procedure the lowest. The analysis of a semen sample, when only the mean of morphometric parameters is used to describe the cell population, is too limited to interpret their fertilizing capacity. It is essential to analyze the complex structure of the samples by defining subpopulations by multivariate methods. With few exceptions, the means of each morphometric parameter differ between the three subpopulations analyzed in each procedure. Only the subpopulations obtained with the MO-NIS procedure showed a significant correlation with male fertility. In short, it is necessary to establish an instrumental standard for the analysis of sperm morphometry to obtain reliable results and we believe that the MO-NIS system presents these basic requirements.
|
|
| 21. |
- Einarsson, S., et al.
(författare)
-
Conference Lecture: Influence of stress on estrus, gametes and early embryo development in the sow
- 2008
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 70:8, s. 1197-1201
-
Tidskriftsartikel (refereegranskat)abstract
- Systems with loose-housed sows have become common. Regrouping, which is commonly done after weaning and may coincide with many important reproductive events, causes stressful situations with elevated blood cortisol concentrations. Depending on group size, approximately 2-7 d are required for a new group of sows to become relatively stable. In a series of studies, the social stress after regrouping was simulated with repeated adrenocorticortriphic hormone (ACTH) treatments for approximately 48 h. Sows were allocated into control and experimental groups, fitted with jugular catheters, and blood samples were collected every 2 or 4 h. Follicular development and ovulation were monitored by transrectal ultrasonography every 4 h. Simulated stress during proestrus prolonged estrus and disturbed the follicular growth and ovulation. Giving ACTH during estrus elevated concentrations of cortisol and progesterone, and chagned the intraluminal environment, including exaggerated amounts of mucus in the UTJ and isthmus. Although ACTH had no effect on the time of ovluation (relative to onset of standing estrus), or on embryo development, fewer oocytes/embryos were retrieved from the ACTH group than from the control group (51% vs. 81%, P less than 0.05), and there was a tendency towards faster embryo transportation to the uterus. Short-term fasting after ovulation had an unfavourable effect on sperm numbers in UTJ/isthmus, cleavage rate of fertlized ova, as well as ova transport through the isthmic part of the oviduct. Treatment with ACTH after ovulation redcued numbers of spermatozoa at the zona pellucida and retarded cleavage rate of fertilized ova. Therefore, the timing of stress seemed to be an important factor regarding effects on reproductive events. (C) 2008 Elsevier Inc. All rights reserved.
|
|
| 22. |
- Einarsson, Stig, et al.
(författare)
-
Occurrence of bacteria and polymorphonuclear leukocytes in fetal compartments at parturition; relationships with foal and mare health in the peripartum period
- 2015
-
Ingår i: Theriogenology. - : Elsevier BV. - 0093-691X .- 1879-3231. ; 84, s. 163-169
-
Tidskriftsartikel (refereegranskat)abstract
- This study investigated the relationship of the health of the newborn foal and (1) number of polymorphonuclear leukocytes (PMNLs) in the amniotic fluid, (2) bacteria present in the amniotic fluid and the venous umbilical blood, and (3) bacteria present in the uterus of the newly foaled mare. A further aim was to investigate relationships between the bacteriologic findings in the amniotic fluid, umbilical blood, and uterus postpartum. Samples were taken from 50 Standardbred trotter foaling mares from a well-managed stud in Sweden. Parturition was spontaneous in all cases. Length of pregnancy, parturition and postpartum complications, health status of the foal, the time between foaling and the expulsion of the placenta, and the number of postfoaling mares becoming pregnant after insemination were recorded. Amniotic fluid was collected when the amniotic vesicle was clearly visible; it was analyzed for bacteriology and occurrence of PMNLs. Umbilical blood was analyzed for the presence of bacteria and the concentration of serum amyloid A. The uterus of themarewas swabbed for bacteriology 6 to 17 hours postpartum. A blood samplewas taken from the foal before administering plasma. The foals were divided into two groups: group 1 required up to 2 hours to rise after birth (2 hours; 31 foals) and group 2 requiredmore than two hours (>2 hours; 19 foals). The length of gestation varied between 332 and 356 days; there was no significant difference in gestation length between the two foal groups. Partus and postpartum complications occurred in a significantly higher proportion of mares giving birth to group 2 foals than group 1 foals (P ¼ 0.02), although uterine culture postpartum and the subsequent pregnancy rate per season were not different between the groups. Compromised health status was significantly higher among foals belonging to group 2 than group 1 (P ¼ 0.001). Most of the amniotic samples contained 5% or less PMNLs. Only three samples contained more than 30% PMNLs; group 2 foals had the highest percentage of PMNLs. Bacterial growth was found in both amniotic fluid (57%) and umbilical blood (35%) in mares irrespective of whether their foals were healthy or compromised. Coagulase-negative staphylococci were the most frequent bacteria. There were no differences in bacterial occurrence in amniotic fluid or in umbilical blood between the two foal groups
|
|
| 23. |
- Einarsson, S., et al.
(författare)
-
Short- and long-term effects of immunization against gonadotropin-releasing hormone, using Improvac (TM), on sexual maturity, reproductive organs and sperm morphology in male pigs
- 2009
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 71:2, s. 302-310
-
Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to determine the short and long term effects of a gonadotropin-releasing hormone (GnRH) vaccine (Improvac (TM) Pfizer Ltd.), on sexual maturity, development of the reproductive organs, and the morphology of caudal epididymal spermatozoa in non-castrated male pigs. The pigs were slaughtered 4, 16 or 22 weeks after the second Improvac (TM) vaccination. A total of 80 crossbred non-castrated male pigs were included in this study comprising two experiments, a short-effect (Experiment 1) and a long-effect (Experiment 2). The first experiment included 56 pigs, 24 of them were maintained as controls and 32 were vaccinated twice, and slaughtered 4 weeks after the second vaccination. The second experiment included 24 pigs, 12 controls and 12 vaccinated twice, and slaughtered either 16 weeks (n = 6) or 22 weeks (n = 6) after the second vaccination. None of the immunized pigs was sexually mature at slaughter, i.e. 4, 16 or 22 weeks after second vaccination. Corresponding results of the control pigs showed that 50% had reached sexual maturity at the age corresponding to 4 weeks after the second vaccination. and 100% at slaughter 16, respectively, 22 weeks after vaccination. At 4, 16 and 22 weeks after second vaccination both testes weight and bulbourethral length were significantly reduced (p less than 0.001). The percentages of proximal droplets and abnormal heads were significantly lower in the control pigs than in the immunized pigs at slaughter 4 weeks after vaccination, whereas distal droplets were higher. For the other morphological parameters no significant differences were seen, but all mean values except for acrosome defects were numerically lower in the control pigs compared with the immunized pigs. For pigs slaughtered 16 or 22 weeks after vaccination, the vaccination effect was significant for percentages of proximal droplets, distal droplets, acrosome defects, acrosome abnormality and abnormal heads (p = 0.017-0.001). The immunization clearly disrupted the number and morphology of the interstitial Leydig cells, lasting throughout the study period (4-22 weeks after vaccination). Spermatogenesis was also clearly affected in the immunized pigs, to various degrees, from mild disruption (spermatocyte loss, decrease of the normal number of layers of germ cells) to severe loss of germ cells including tubuli with Sertoli cells-only (complete disappearance of germ cells), also covering the entire study period. The results indicated that the effect of immunization persisted for at least 22 weeks after the second vaccination. (c) 2009 Elsevier Inc. All rights reserved.
|
|
| 24. |
- Ekwall, Hans, et al.
(författare)
-
Cryo-scanning electron microscopy (Cryo-SEM) of boar semen frozen in medium-straws and MiniFlatPacks
- 2007
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 67:9, s. 1463-1472
-
Tidskriftsartikel (refereegranskat)abstract
- In this study we demonstrate, in the frozen state, the architecture of frozen boar spermatozoa collected from the sperm-rich fraction of ejaculates (n = 13) from four fertile boars packed and split-frozen in medium-straws (MS) and MiniFlatPacks (MFP), cross-sectioned in the frozen state and evaluated by image analysis on images obtained by use of cryo-scanning electron microscopy (Cryo-SEM). The tested hypothesis was that the degree of in situ dehydration and levels of homogeneity of boar semen either frozen in MSs or MFPs packages differ between them, with MFPs allowing for a more uniform dehydration of the spermatozoa and a higher cryosurvival, monitored by computer assisted sperm analysis (CASA) as proportion of linearly motile spermatozoa, compared to semen packaged and processed in MSs. The organization and relative surface of biological material (veins; e.g., frozen extender, bound water, solutes and spermatozoa) as well as free water (lakes) was measured as the degree of dehydration of the samples. The apparent organization of lakes and veins differed between packages, with the MFPs depicting larger lakes than the MSs. The sizes of the lakes in the latter appeared, moreover, highly asymmetrical depending on their position of the section. The relative surface of these lakes per section, respectively veins differed between packages (P less than 0.05), indicating a larger amount of free-water (lakes; 81.73 +/- 2.07% vs. 77.91 +/- 1.57%) in the MFPs and, consequently, thinner veins than in MSs. In conclusion, MFPs seem to allow for a more homogenous dehydration of the spermatozoa/frozen extender compared to MSs, which might account for their somewhat better sperm quality post-thaw. (C) 2007 Elsevier Inc. All rights reserved.
|
|
| 25. |
- Elwing, Bodil, et al.
(författare)
-
Effect of different freezing rates and thawing temperatures on cryosurvival of dromedary camel spermatozoa
- 2019
-
Ingår i: Theriogenology. - : Elsevier BV. - 0093-691X .- 1879-3231. ; 125, s. 43-48
-
Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to evaluate the effect of different freezing rates and thawing temperatures on the post-thaw quality of camel spermatozoa. Ten ejaculates from five male camels were frozen at five different freezing rates, achieved by placing the straws at specific heights above the surface of liquid nitrogen for different lengths of time (4 cm for 15 min; 1 cm for 15 min; 7 cm for 15 min; 7 cm for 5 min + 4 cm for 3 min; 4 cm for 5 min + 1 cm for 3 min) followed by storage in liquid nitrogen. Two thawing temperatures (37 degrees for 30 s and 60 degrees C for 10 s) were subsequently tested. Post-thawing, the samples were evaluated for total and progressive motility, kinematics, membrane and acrosome integrity, and membrane functionality (hypoosmotic swelling test) at zero and 1 h post thawing. Total and progressive motility were significantly higher for the fastest freezing rate (at 1 cm) at 0 h (p < 0.01 for both), as were VCL (p < 0.01), VSL (p < 0.05) and STR (p < 0.05). Freezing at 4 cm produced the lowest values of STR compared to other treatments (p < 0.05). At 1 h, no differences in total motility were observed between freezing at 4 cm and 1 cm, both being significantly better than freezing rate 7 cm + 4 cm (p < 0.01). For progressive motility and VSL, only freezing at 1 cm was superior to the 7 cm + 4 cm combination (p < 0.001 and p < 0.05 respectively). Membrane integrity at 1 h was higher for freezing at 7 cm than at 1 cm (p < 0.01). For thawing temperatures, total motility and progressive motility at 0 h and 1 h (p < 0.001), and acrosome integrity at 1 h (p < 0.01) were higher for 60 degrees C thawing temperature than 37 degrees C. The kinematics VCL (p < 0.001), VSL and STR (p < 0.01), and VAP (p < 0.05) showed higher values for 60 degrees C thawing temperature than 37 degrees C at 0 h. After 1 h, higher values for VSL, VCL and VAP (p < 0.05) were observed for 60 degrees C than for 37 degrees C. In conclusion, a fast freezing rate would probably be beneficial for camel semen, and thawing should be conducted at 60 degrees C. (C) 2018 Published by Elsevier Inc.
|
|
