| 1. |
|
|
| 2. |
- Abraham, Maria Celina, et al.
(författare)
-
Effect of sperm preparation on development of bovine blastocyst in vitro
- 2016
-
Ingår i: Zygote. - 0967-1994 .- 1469-8730. ; 24, s. 825-830
-
Tidskriftsartikel (refereegranskat)abstract
- colloids has been used to select normal sperm for assisted reproduction in several species. Animal models can sometimes be used as a preliminary step to investigate sperm preparation methods that are potentially of use for human fertility treatments. In this study bovine semen was prepared using three variants of the single-layer centrifugation sperm selection technique (Small, Mini, Mini-EP) with Bovicoll (Androcoll-B). Computer-assisted sperm motility analysis, the hypo-osmotic swelling test, and the sperm chromatin structure assay were performed on unselected (control) and SLC-selected sperm samples. Mini and Mini-EP gave the highest yield of motile spermatozoa, progressive motility and membrane integrity. In vitro fertilization trials were performed to investigate the fertilizing ability of the frozen-thawed bovine spermatozoa selected with Bovicoll. Mini-SLC (single-layer centrifugation) and swim-up (Control) were performed and cleavage rate and blastocyst rate did not differ significantly between groups. As there was a trend to an increased number of cells in blastocysts in the SLC group, the Mini-SLC method is at least as good as swim-up for selecting frozen-thawed bull spermatozoa for in vitro fertilization (IVF). This method could potentially be used to prepare human sperm for assisted reproduction.
|
|
| 3. |
- Abraham, Maria Celina, et al.
(författare)
-
Semen collection methods in alpacas
- 2017
-
Ingår i: Veterinary Record. - : Wiley. - 0042-4900 .- 2042-7670. ; 180, s. 613-614
-
Forskningsöversikt (refereegranskat)abstract
- South American camelids, particularly alpacas, are gaining in popularity outside their native lands. Reproductive biotechnologies, such as artificial insemination or embryo transfer with cryopreserved embryos, are more complicated in these species than many others due to differences in their reproductive physiology compared to the more commonly encountered domestic livestock. This article reviews the methods currently available for obtaining semen or spermatozoa from alpacas and describes some of the problems associated with handling the viscous seminal plasma characteristic of camelids. Possibilities and limitations of reproductive biotechnologies in this species are discussed, and future developments are outlined, especially some new techniques which are currently being developed for use with camel semen and may be transferable to alpacas.
|
|
| 4. |
|
|
| 5. |
- Abraham, Maria Celina, et al.
(författare)
-
Testicular length as an indicator of the onset of sperm production in alpacas under Swedish conditions
- 2016
-
Ingår i: Acta Veterinaria Scandinavica. - : Springer Science and Business Media LLC. - 0044-605X .- 1751-0147. ; 58
-
Tidskriftsartikel (refereegranskat)abstract
- Background The popularity of alpacas (Vicugna pacos) is increasing in Sweden as well as in other countries; however, knowledge about optimal management practices under Swedish conditions is still limited. The wide age range reported when the onset of puberty can occur, between 1 and 3years of age, makes management decisions difficult and may be influenced by the conditions under which the alpacas are kept. The aim of this study was to find out when Swedish alpacas can be expected to start producing sperm, by using testicular length and body condition score as a more precise indirect indicator than age. Results This study suggests that animals with a testicular length ≥3.8cm would be producing sperm; however, if it is crucial to know that there is no sperm production for management purposes, the threshold level for testicular length used to differentiate between sperm-producing and non-sperm producing animals should be ≤1.6cm instead. If only one variable is considered, testicular length appears to better than age alone to predict sperm production. Body condition score together with testicular length explains the individual onset of puberty and better guide management recommendations. Conclusions Using a combination of these parameters (testicular length, body condition score and age) as a tool for decision making for alpaca husbandry under Swedish conditions is suggested.
|
|
| 6. |
|
|
| 7. |
- Al-Essawe, Essraa M, et al.
(författare)
-
Addition of seminal plasma to thawed stallion spermatozoa did not repair cryoinjuries
- 2018
-
Ingår i: Animal Reproduction Science. - : Elsevier BV. - 0378-4320 .- 1873-2232. ; 196, s. 48-58
-
Tidskriftsartikel (refereegranskat)abstract
- Freezing and thawing processes induce structural and functional damage to sperm plasma membranes and internal organelles. Adding seminal plasma (SP) has been found to minimize or repair the cryoinjuries in some species. The objective of this study was to investigate whether adding SP from stallions of known freezability after thawing could repair cryoinjuries. Semen was collected from warmblood stallions (n = 8, three ejaculates/stallion) and processed by Single Layer Centrifugation (SLC) to remove SP prior to freezing. Pooled SP (5%) from bad freezer (BF) or good freezer (GF) stallions was added after thawing. Post-thaw sperm quality was assessed by flow cytometry in terms of chromatin integrity (ßI), membrane integrity, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and MitoSOX. Sperm kinematics were also assessed by computer-assisted sperm analysis. The ßI was lower in SLC control (C) than in BF or GF (P < 0.0001, P < 0.0003 respectively). The proportion of viable spermatozoa with intact cell membranes was higher in C than in SP treated groups (C vs. BF, P = 0.02; C vs GF, P = 0.05). There were fewer spermatozoa with low MMP and more with high MMP for C than GF (P = 0.006). The spermatozoa treated with SP from good freezers produced more ROS than when treated with SP from bad freezers (P = 0.007). Motility parameters were not affected by adding SP. In conclusion, adding SP after thawing does not have a beneficial effect on sperm quality, suggesting an inability to repair stallion sperm cryoinjuries, regardless of whether the SP originated from stallions semen, which has good or bad quality after thawing.
|
|
| 8. |
|
|
| 9. |
- Al-Essawe, Essraa M, et al.
(författare)
-
Extenders for alpaca epididymal spermatozoa: Comparison of INRA96 and andromed
- 2020
-
Ingår i: Animal Reproduction Science. - : Elsevier BV. - 0378-4320 .- 1873-2232. ; 223
-
Tidskriftsartikel (refereegranskat)abstract
- Artificial insemination would be a useful technique for alpaca breeders to use as an aid to breeding to increase fleece quality. The technique, however, is not well developed in alpacas, partly because of the viscous nature of their seminal plasma. Castration conducted for husbandry purposes can provide a source of epididymal spermatozoa to test semen extenders or handling regimens, thus circumventing the problem of the viscous ejaculate. In this experiment, two semen extenders (Andromed and INRA96) developed for other species (bovine and equine, respectively) were tested with alpaca spermatozoa derived from the cauda epididymis. Sperm total motility (mean ± SEM A: 29.1 ± 4.8 % compared with I: 35.4 ± 4.8 %; NS), membrane integrity (A: 58 ± 9% compared with I: 56 ± 9%; NS) and acrosome integrity (A: 65 ± 7% compared with I: 54 ± 7%; NS) were not different between the two extenders. Progressive motility with use of INRA96 was greater after incubating for 30 min than after incubating for 10 min (35 ± 4% vs. 12 ± 4%, respectively; P = 0.03). In conclusion, viable epididymal spermatozoa could be extracted from the castrated organs after overnight transport. There were no differences in sperm quality between the two extenders; therefore, it appears that either extender could be used for alpaca spermatozoa. These results could help in the development of a technique for artificial insemination in alpacas.
|
|
| 10. |
- Al-Essawe, Essraa M, et al.
(författare)
-
Improved cryosurvival of stallion spermatozoa after colloid centrifugation is independent of the addition of seminal plasma
- 2018
-
Ingår i: Cryobiology. - : Elsevier BV. - 0011-2240 .- 1090-2392. ; 81, s. 145-152
-
Tidskriftsartikel (refereegranskat)abstract
- Addition of seminal plasma (SP) prior to cryopreservation may influence stallion sperm cryosurvival. The objective of this study was to investigate the addition of pooled SP from "good" or "bad" freezer stallions to spermatozoa selected by single layer centrifugation (SLC) prior to cryopreservation on post-thaw sperm quality. Semen from 12 stallions was collected; 5 mL was frozen as control (C) and the remainder was processed by SLC to remove SP and was divided into three aliquots: i) SLC sample without SP (SLC); ii) SLC plus pooled SP from "good freezer" stallions (SLC-GF); iii) SLC plus pooled SP from "bad freezer" stallions (SLC-BF). After thawing, the following parameters were evaluated: chromatin integrity (DNA fragmentation index; ßI), mitochondria) membrane potential (MMP), membrane integrity (MI), reactive oxygen species (ROS) and sperm kinematics. The ßI was reduced (P < 0.0001) in SLC samples compared to controls. The SLC group showed a lower proportion of spermatozoa with low MMP and a higher proportion of spermatozoa with high MMP than other groups (P < 0.0001), and had lower hydrogen peroxide content than control. Sperm kinematics were not different. In conclusion, selection by SLC prior to cryopreservation improved post-thaw sperm quality; inclusion of SP from "good" and "bad" freezer stallions did not have an additional beneficial effect.
|
|
