19 research outputs found

    Practical applications of sperm selection techniques for improving reproductive efficiency

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    Several selection techniques are available for processing spermatozoa. Apart from sperm washing to remove seminal plasma, only "swim-up" and colloid centrifugation have been used to any extent to prepare spermatozoa for in vitro fertilization, and only colloid centrifugation has been used to prepare sperm samples for artificial insemination. Single-layer centrifugation (SLC) through a species-specific colloid has been shown to be effective in selecting spermatozoa with good motility, normal morphology and intact chromatin in a range of species. This method is less timeconsuming than swim-up, and has been scaled-up to allow whole ejaculates to be processed in a practical manner. The applications of SLC are as follows: to improve sperm quality in insemination doses or in samples for in vitro fertilization, to increase the shelf life of normal sperm doses, to remove pathogens (viruses, bacteria), to improve cryosurvival by removing dead and dying spermatozoa before freezing or after thawing, to select spermatozoa for intracytoplasmic sperm injection, and to aid conservation breeding

    Could a different management routine that strengthens the mother-offspring bond contribute to a more efficient organic piglet production?

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    In current Swedish organic piglet production full reproductive potential of the sows and growth potential of piglets are not achieved. The efficiency is held back by occurrence of lactational oestrus, low litter weight and large weight variation within litter. Therefore it is critical that these obstacles are reduced in a way that is easy to adapt in practice and does not contradict the ideas behind organic animal husbandry. This project aims to an improvement of the conditions needed to efficiently produce organic piglets in a batch wise manner. The batch wise breeding will reduce production costs and increase disease control. Our preliminary results indicate that the sow’s weaning to oestrus interval can be affected by the time spent in individual farrowing pen during the lactational period

    Practical applications of sperm selection techniques for improving reproductive efficiency

    No full text
    Several selection techniques are available for processing spermatozoa. Apart from sperm washing to remove seminal plasma, only "swim-up" and colloid centrifugation have been used to any extent to prepare spermatozoa for in vitro fertilization, and only colloid centrifugation has been used to prepare sperm samples for artificial insemination. Single-layer centrifugation (SLC) through a species-specific colloid has been shown to be effective in selecting spermatozoa with good motility, normal morphology and intact chromatin in a range of species. This method is less timeconsuming than swim-up, and has been scaled-up to allow whole ejaculates to be processed in a practical manner. The applications of SLC are as follows: to improve sperm quality in insemination doses or in samples for in vitro fertilization, to increase the shelf life of normal sperm doses, to remove pathogens (viruses, bacteria), to improve cryosurvival by removing dead and dying spermatozoa before freezing or after thawing, to select spermatozoa for intracytoplasmic sperm injection, and to aid conservation breeding

    Practical Applications of Sperm Selection Techniques as a Tool for Improving Reproductive Efficiency

    No full text
    Abstract Several selection techniques are available for processing spermatozoa. Apart from sperm washing to remove seminal plasma, only "swim-up" and colloid centrifugation have been used to any extent to prepare spermatozoa for in vitro fertilization, and only colloid centrifugation has been used to prepare sperm samples for artificial insemination. Single-layer centrifugation (SLC) through a species-specific colloid has been shown to be effective in selecting spermatozoa with good motility, normal morphology and intact chromatin in a range of species. This method is less timeconsuming than swim-up, and has been scaled-up to allow whole ejaculates to be processed in a practical manner. The applications of SLC are as follows: to improve sperm quality in insemination doses or in samples for in vitro fertilization, to increase the shelf life of normal sperm doses, to remove pathogens (viruses, bacteria), to improve cryosurvival by removing dead and dying spermatozoa before freezing or after thawing, to select spermatozoa for intracytoplasmic sperm injection, and to aid conservation breeding

    Effect of energy balance profiles on metabolic and reproductive response in Holstein and Swedish Red cows

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    This study examined the effect of two feeding levels during the antepartum and postpartum period on reproductive performance and blood metabolites (glucose, non-esterified fatty acids (NEFA), insulin) in primiparous Holstein and Swedish Red (SRB) cows, in order to identify possible differences in the way these breeds respond to negative energy balance after calving. A total of 44 cows (22 Holstein, 22 SRB) kept in a loose housing system were included in the study. The control group (HE, n = 23) was fed a diet for high-producing cows (target 35 kg/d energycorrected milk, ECM). A lower feeding intensity (LE, n = 21) was achieved by giving -50% concentrate to target 25 kg/d ECM. Diets were implemented 30 days before expected calving and the cows were monitored for 120 days postpartum. Milk yield and composition, dry matter intake (DMI), live body weight and body condition score (BCS) were assessed to calculate the weekly energy balance (residual feed intake). Blood sampling started before diet implementation and was repeated every 2 weeks until Day 60 postpartum and then once monthly until Day 120. Plasma was kept at −20 °C until analysis for glucose, insulin and NEFA concentrations. Mixed linear models were used to analyse data (SAS 9.3; PROC MIXED). Holstein cows had lower mean energy balance than SRB cows (−4.7 ± 1.4 and −0.9 ± 1.4 MJ, respectively; p = 0.05). SRB cows had higher (p<0.001) BCS (3.3 ± 0.1) than Holstein cows (2.7 ± 0.1) and also higher plasma glucose concentrations from Day -30 to Day 120 relative to parturition (4.1 ± 0.1 and 4.2 ± 0.1 log ; mg/100 ml, respectively; p < 0.05). Overall, breed or diet had no effect on NEFA blood plasma concentrations. However, plasma NEFA concentration levels tended to be higher (p = 0.09) in SRB cows than in Holsteins at Day -14 before calving, indicating higher mobilisation of lipid from adipose tissue already before calving. In contrast, Holstein cows had higher NEFA at Day 14 postpartum than SRB cows (p < 0.05). There were no significant effects of diet or breed on reproductive performance (% pregnant at first AI, days open). However, commencement of luteal activity within 21d postpartum was affected (p < 0.05) by the interaction of breed and diet. These results suggest that Holstein cows prioritise milk production to a larger extent than SRB cows, resulting in a less balanced metabolic profile
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