| 1. |
- Abraham, Maria Celina, et al.
(författare)
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Semen collection methods in alpacas
- 2017
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Ingår i: Veterinary Record. - : Wiley. - 0042-4900 .- 2042-7670. ; 180, s. 613-614
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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.
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| 2. |
- Abraham, Maria Celina, et al.
(författare)
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Testicular length as an indicator of the onset of sperm production in alpacas under Swedish conditions
- 2016
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Ingår i: Acta Veterinaria Scandinavica. - : Springer Science and Business Media LLC. - 0044-605X .- 1751-0147. ; 58
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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.
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| 3. |
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| 4. |
- Abrahmsén, Markus, et al.
(författare)
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Prevalence of subclinical mastitis in dairy farms in urban and peri-urban areas of Kampala, Uganda
- 2014
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Ingår i: Tropical Animal Health and Production. - : Springer Science and Business Media LLC. - 0049-4747 .- 1573-7438. ; 46, s. 99-105
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Tidskriftsartikel (refereegranskat)abstract
- It is widely recognized that subclinical mastitis (SCM) is an extensive problem in the dairy industry worldwide. It is of particular concern in developing countries. The aim of this study was to establish the prevalence of SCM in dairy cattle in the urban and peri-urban areas of Kampala, Uganda and to gain information about pathogens and antibiotic resistance patterns. The study was conducted as a field study in 18 smallholder dairy farms in peri-urban Kampala, Uganda. All cows at the farms were physically examined, and cows with signs of clinical mastitis were excluded. Cows (n = 195) were tested with California Mastitis Test (CMT), and udder quarters with CMT score a parts per thousand yen3 (scale 1-5) were milk sampled for bacteriological analysis. To allow further sub-analysis of the results, the stage of lactation, parity, milk production, production type, udder hygiene, and cow breed were recorded. Results indicate that 86.2 % (n = 168) of the tested cows had SCM in one or more quarters. The most common bacteriological outcome was infection with coagulase-negative staphylococci (54.7 %), followed by negative growth (24.9 %) and streptococci (16.2 %); all of which (n = 34) were sensitive to penicillin. Of the tested staphylococci (n = 17), the majority (58.9 %) were positive for penicillinase production. Factors with significant impact on the prevalence of SCM at cow level were the stage of lactation, parity, and production type. The results suggest that the prevalence of SCM in Uganda is substantially higher than reported in previous studies and in other comparable developing countries. This implies that SCM deserves more attention and that improvement in dairy cow husbandry in terms of hygiene and management is necessary.
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| 5. |
- Al-Essawe, Essraa M, et al.
(författare)
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Extenders for alpaca epididymal spermatozoa: Comparison of INRA96 and andromed
- 2020
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Ingår i: Animal Reproduction Science. - : Elsevier BV. - 0378-4320 .- 1873-2232. ; 223
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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.
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| 6. |
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| 7. |
- Andrée O´ Hara, Elisabeth, et al.
(författare)
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An observational study of the dry period length and its relation to milk yield, health, and fertility in two dairy cow breeds
- 2020
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Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 175
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Tidskriftsartikel (refereegranskat)abstract
- This study evaluated associations between dry period length (DPL) in dairy cows and energy-corrected milk (ECM) production, health, and fertility, using a dataset involving 78 577 lactations in cows of two breeds, Swedish Red (SR) and Swedish Holstein (SH). Herds with at least 20 cows and at least 20 % purebred SR and at least 20 % SH during the year 2015/2016 were included in the dataset. Cows were divided into parity groups 2 and 3 or older and DPL was classified into six 10-day groups (30-39 to 80-89 d). Associations between DPL and the outcome variables were assessed with linear and generalized linear mixed models. Production of ECM at the first three test milkings and the 305-d lactation was highest in the 50-59 d and 60-69 d DPL groups, and lowest in the 30-39 d and 80-89 d groups (p<0.001). Mastitis and somatic cell count (SCC) did not differ between DPL groups, except at the third test milking, where cows in the 40-49, 50-59, and 60-69 DPL groups had lower SCC (p<0.001) than cows in the 70-79 and 80-89 d groups. The odds ratio (OR) for retained placenta was 1.9 for cows with 30-39 d DPL relative to cows with 60-69 d DPL. Cows in DPL groups 40-49 d and 50-59 ha d the lowest odds of culling (OR=0.89 and 0.92). The OR for culling in cows with DPL 70-79 d and 80-89 was 1.2 and 1.4, respectively, relative to cows with 60-69 d DPL. The conception rate at first insemination did not among between DPL groups. The SR cows produced less ECM than the SH cows, but had lower SCC and lower OR for mastitis, retained placenta, puerperal paresis, and culling within 90 DIM. Although DPL <40 days or >80 days reduced milk production in early lactation and the 305-d lactation, the estimated additional milk production in the preceding lactation in cows with short DPL compensated for this reduction. A DPL of 40 days did not affect health and fertility in comparison with a conventional 60 d DPL, while a DPL of >70 d was unfavorable due to low milk production, increased risk of culling, and decreased fertility. The response to DPL was not affected by breed or parity.
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| 8. |
- Andrée O´ Hara, Elisabeth, et al.
(författare)
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Effects of dry period length on metabolic status, fertility, udder health, and colostrum production in 2 cow breeds
- 2019
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Ingår i: Journal of Dairy Science. - : American Dairy Science Association. - 0022-0302 .- 1525-3198. ; 102, s. 595-606
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Tidskriftsartikel (refereegranskat)abstract
- Shortening the dry period improves postpartum energy balance, which has potential positive effects on metabolic health. This concept has been mainly studied in Holstein cows. The aim of this study was to assess the effect of a short dry period of 4 wk, compared with a standard dry period of 8 wk, on the metabolic status, progesterone profiles, health, and colostrum quality of dairy cows of 2 breeds, Swedish Red (SR) and Swedish Holstein (SH), not treated with antibiotics at dry off. The IgG uptake in calves was also studied to reflect the colostrum quality when shortening the dry period. Cows of both SH and SR were blocked by breed and parity and then randomly allocated to a short dry period of 4 wk (4W, n = 43) or a conventional dry period of 8 wk (8W, n = 34). Blood samples were collected wk 8, 4, 2, 1 and 1, 2, 3, 4, 6, 9, and 12 relative to calving. Prepartum, cows with a 4-wk dry period had higher concentrations of nonesterified fatty acids and lower concentrations of insulin-like growth factor-1. and insulin than 8W cows. Postpartum, plasma concentration of nonesterified fatty acids was lower, whereas plasma insulin and insulin-like growth factor-1 tended to be higher for 4W cows than for 8W cows. Plasma concentration of beta-hydroxybutyrate did not differ between dry period lengths. Swedish Holstein cows with a 4W dry period responded with a lower concentration of insulin prepartum than SR and SH on an 8W dry period. The dry period length had no effect on the proportion of disturbed progesterone profiles; disturbed progesterone profiles occurred in 30% of the 4W cows and 47% of the 8W cows. In this trial, only 48.8% of the SR cows had a normal progesterone profile, which differed from the SH where 76.5% had a normal profile. Fertility-related diseases (endometritis, pyometra, anestrus, ovarian cyst) did not differ between the 2 dry period groups: 21% in the 8W group versus 12% in the 4W group, whereas mastitis tended to be more common: 26% of the 4W cows versus 9% of the 8W cows. A short dry period resulted in less colostrum but with a higher content of protein and somatic cell count. Calves were fed colostrum from their dam, and the IgG and total protein in plasma did not differ between calves to mothers with different a dry period length. Shortening the dry period could improve metabolic status in cows of both SH and SR breed postpartum, without compromising the colostrum quality. Health and progesterone profiles were not affected by the dry period length for SH or SR in this study.
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| 9. |
- Andrée O´ Hara, Elisabeth, et al.
(författare)
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Effects of dry period length on milk production and energy balance in two cow breeds
- 2018
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Ingår i: Animal. - 1751-7311 .- 1751-732X. ; 12, s. 508-514
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Tidskriftsartikel (refereegranskat)abstract
- Shortening the dry period (DP) has been proposed as a strategy to improve energy balance (EB) in cows in early lactation. This study evaluated the effects of shortening the DP on milk yield (MY), EB and residual feed intake (RFI) in two breeds; Swedish Red (SR) and Swedish Holstein (SH). Cows were blocked by breed and parity and then randomly assigned to one of two treatments; short DP of 4 weeks (4W, n = 43) or conventional DP of 8 weeks (8W, n = 34). Cows were kept and fed under the same conditions, except for the 4 weeks when the 4W group were still lactating prepartum and thus kept with the lactating cows. Milk yield and BW were recorded and body condition score (BCS) was rated from 10 weeks prepartum to 12 weeks postpartum. Dry matter intake (DMI) was recorded for lactating cows postpartum. Milk yield was reduced by 6.75 kg/day during the first 12 weeks postpartum ( P< 0.001) for the 4W cows compared with 8W cows, but there was no significant difference in total MY (3724 kg compared with 3684 kg, P = 0.7) when the milk produced prepartum was included. Protein content was higher in 4W cows (3.42%) than in 8W cows (3.27%) ( P<0.001) postpartum. In the 8W group, cows lost more BCS after calving ( P<0.05). Cows of SR breed had higher BCS than cows of SH breed (SR = 3.7, SH = 3.2, P< 0.001), but no differences in BW were found between breed and treatment. Energy balance was improved for cows in the 4W group ( P< 0.001), while feed efficiency, expressed as RFI, was reduced for 4W cows than for 8W cows (5.91 compared with −5.39, P<0.01). Shortening the DP resulted in improved EB postpartum with no difference between the breeds and no milk losses when including the milk produced prepartum.
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| 10. |
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