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C W Rogers - One of the best experts on this subject based on the ideXlab platform.
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the dynamics of energy supply and demand of Foaling mares managed at pasture a deterministic modelling approach
Animal Production Science, 2020Co-Authors: Y Y Chin, E K Gee, F Roca J Fraga, P J Back, C W RogersAbstract:Context. At pasture, the nutritional status of mares will change due to a dynamic association between their energy requirements and the energy supply. Change in the plane of nutrition can influence reproductive performance measures in the mares. To help optimise nutritional and operational management of mares on stud farms, the nutritional status of Thoroughbred broodmares and the factors influencing the energy supply and demand were investigated. Aims. To assess nutritional status of the Thoroughbred broodmare herds under ‘normal’ New Zealand commercial stud-farm conditions. Methods. The energy intake, energy requirement and energy balance during the last 3 months of pregnancy and the first 5 months of lactation were modelled for mares with an initial bodyweight of 450 kg, 500 kg, 550 kg and 600 kg, and foaled at 0, 15, 50, and 90 days after 1 September. Key results. For all Foaling dates and bodyweights, mares were in positive energy balance during the last 3 months of pregnancy (6.1–8.5%). Energy balance decreased as pregnancy progressed, followed by a large and acute energy deficit that was initiated soon after Foaling and continued during lactation. The energy deficit during lactation varied between –8.6% and –12.4%, depending on the Foaling date modelled. Mares Foaling later in the season (50–90 days after 1 September) had greater and longer (30–50 days) postpartum energy deficit than did mares that foaled earlier in the season, who recovered within 20 days postpartum. The modelled changes in the energy balance would be large enough to initiate mobilisation of the fat reserve (body condition), and could, therefore, explain the observation of delayed postpartum to conception interval observed with later-Foaling mares on commercial farms. Conclusions. There is a large and prolonged energy deficit soon after Foaling and throughout 150 days of lactation in Thoroughbred mares managed under New Zealand commercial grazing conditions. Foaling later in the season can cause a mismatch in energy supply and demand that would increase and prolong the energy deficit. Implications. These findings suggest a need for stud farms to actively manage the pasture supply and monitor the mare’s BWT and BCS changes in an attempt to optimise the mare’s nutritional status and reproductive performance.
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gestation length and occurrence of daytime Foaling of standardbred mares on two stud farms in new zealand
New Zealand Veterinary Journal, 2012Co-Authors: M Dicken, E K Gee, C W Rogers, I G MayhewAbstract:Abstract AIMS: To examine the gestation lengths and occurrence of daytime Foaling of Standardbred mares Foaling outdoors at stud farms in Southland, New Zealand (latitude 45˚S). METHODS: Data were collected prospectively at two commercial Standardbred stud farms (Farms A and B), during the 2008/9 and 2009/10 breeding seasons (October to February). For each Foaling, the identity of the mare, date and time of Foaling, gender of foal, time the mare passed the fetal membranes, time the foal stood, and Foaling problems including dystocias, were recorded. The effect of farm, season, gender of foal, month of artificial insemination (AI) or Foaling, age and parity of mare on gestation length, percentage of mares Foaling during daylight hours, and percentage of Foalings recorded as dystocia, were examined. RESULTS: A total of 614 Foaling records were obtained from 507 mares. For 594 Foalings with complete records, mean gestation length was 349 (SE 0.5) days. Mean gestation length was shorter for fillies (347.8 (SE...
Ben Colenbrander - One of the best experts on this subject based on the ideXlab platform.
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prediction of first season stallion fertility of 3 year old dutch warmbloods with prebreeding assessment of percentage of morphologically normal live sperm
Equine Veterinary Journal, 1999Co-Authors: J M Parlevliet, Ben ColenbranderAbstract:Summary In the selection procedure to acquire a breeding licence, 3-year-old Dutch Warmblood stallions have to undergo a breeding soundness test It is questioned whether this evaluation is predictive of the stallion's fertility results in the first breeding season. Therefore, semen parameters at the beginning of their first breeding season were evaluated and correlated to nonreturn at first cycle and Foaling rate of mares bred by stallions (n = 13). The total number of mares inseminated with chilled semen from those stallions was 1055. Semen parameters were recorded on 2 ejaculates, collected 1 h apart. Percentage progressive sperm motility, % morphologically normal from unstained spermatozoa (MNA), % sperm cells with abnormal acrosomes and the total number of spermatozoa were correlated with first cycle nonreturn rate and Foaling rate. Mean motility at evaluation was 72 ± 6%. Mean MNA was 62 ± 13%. Mean first cycle nonreturn rate and Foaling rate were 58 ± 15% and 69 ± 12%, respectively. A significantly positive correlation (P<0.05) was found between the MNA and first cycle nonreturn rates. Foaling rates were not significantly correlated with semen characteristics and first cycle nonreturn rates. In conclusion, the breeding soundness test is of predictive value for the breeding results in the breeding season following the test. First cycle nonreturn rates reflect fertilising capacity better than Foaling rates.
Terttu Katila - One of the best experts on this subject based on the ideXlab platform.
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A 15-year survey of reproductive efficiency of Standardbred and Finnhorse trotters in Finland - descriptive results
Acta Veterinaria Scandinavica, 2010Co-Authors: Terttu Katila, Tiina Reilas, Kaisa Nivola, Terttu Peltonen, Annamaija VirtalaAbstract:Background The major horse breeds in Finland are the Finnhorse (FH) and the American Standardbred (SB). The Foaling rates of the FH have consistently been lower than those of the SB. During the last years, a decreasing trend in Foaling rates of both breeds has been observed. The purpose of this study was to describe and compare the structure of these two mare populations for age, reproductive history and mating type. In addition, changes over the years were studied that could explain the decline in Foaling rates. Methods In Finland, the mating statistics and Foaling rates per stallion are published yearly by Suomen Hippos, which is the Finnish trotting and breeding association authorized by the EU. The studied material was the electronic breeding data of Suomen Hippos in 1991-2005 which contained 69 180 cases (one mare bred in one year with one stallion), 20 168 mares, 2 230 stallions and 5 397 stud managers. The effect of mare age and type, mating type and changes during the study period were examined separately for FH and SB using SAS 9.1 for descriptive statistical analyses (frequencies, percentages, means, standard deviations and confidence intervals). The outcome of the last mating per season (foal or not) was used in the calculation of the Foaling rates. Results The FH mares were on average one year older and belonged to the older age groups more often than the SB mares. Ageing decreased Foaling rates and even more in FH; the Foaling rates were the following: young FH 68.6 and SB 72.1%, middle-aged FH 66.1 and SB 71.9%, ageing FH 61.2 and SB 68.4%, and very old FH 52.8 and SB 61.8%. The foaled mares were more frequent in the SB (45%) than in the FH (37%), but the barren and rested mares were more common in the FH. Natural mating was more commonly practiced in the FH as compared to the SB. The Foaling rates decreased from 1991 to 2005 in SB from 75.1 to 65.9% and in FH from 66.5 to 60.8%. For both breeds, the proportion of young mares decreased and the proportion of very old mares increased over the years. Similarly, the proportion of foaled mares in both breeds decreased and the proportion of barren mares increased during the study period. In both breeds, insemination (AI) by transported cooled semen increased, diminishing the on-site AI in the SB and the natural mating in the FH. Conclusions The results of this study suggest that mare age and type and mating type all affect Foaling rates and that the structural differences in the mare populations can explain differences in the Foaling rates between the horse breeds and between the time periods.
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a 15 year survey of reproductive efficiency of standardbred and finnhorse trotters in finland descriptive results
Acta Veterinaria Scandinavica, 2010Co-Authors: Terttu Katila, Tiina Reilas, Kaisa Nivola, Terttu Peltonen, Annamaija VirtalaAbstract:Background The major horse breeds in Finland are the Finnhorse (FH) and the American Standardbred (SB). The Foaling rates of the FH have consistently been lower than those of the SB. During the last years, a decreasing trend in Foaling rates of both breeds has been observed. The purpose of this study was to describe and compare the structure of these two mare populations for age, reproductive history and mating type. In addition, changes over the years were studied that could explain the decline in Foaling rates.
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onset of luteal activity in Foaling and seasonally anoestrous mares treated with artificial light
Acta Veterinaria Scandinavica, 1991Co-Authors: Erkki Koskinen, Eeva Kurki, Terttu KatilaAbstract:Sixty-four mares (27 Foaling, 37 barren or maiden), mainly Finnhorses, were subjected to treatment with 14.5 h of light and 9.5 h of darkness, starting at the beginning of December. The onset of cycling in non-Foaling mares was estimated by weekly serum progesterone determinations. All of the non-Foaling mares cycled in the middle of March. They started to cycle on average in the middle of February, 11.1 weeks after the beginning of the trial. There were statistically significant differences in relation to breed (Finnhorses started to cycle 2 weeks later than warm blooded, p less than 0.02) and in relation to age (brood mares with mean age 10 years, started to cycle 10 days later than those 3 years old, p less than 0.03). However, there was no statistical significant relation to previous lactation, although lactating mares lactating up to the previous autumn started to cycle 7 days later than dry mares (p less than 0.15). Artificial insemination of 14 mares in the 2nd oestrus of the year, in March, resulted in 12 Foalings in the subsequent year (86%). The following winter, all pregnant mares (N = 27) were exposed to the same kind of light treatment, starting on 1st December. The 1st mare foaled at the end of January. The time from Foaling to 1st post partum ovulation was significantly longer (17.0 days) in Foalings taking place within 10 weeks from the beginning of the light treatment period, than in Foalings occurring after more than 10 weeks of lighting (12.1 days) (p less than 0.01).
E K Gee - One of the best experts on this subject based on the ideXlab platform.
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the dynamics of energy supply and demand of Foaling mares managed at pasture a deterministic modelling approach
Animal Production Science, 2020Co-Authors: Y Y Chin, E K Gee, F Roca J Fraga, P J Back, C W RogersAbstract:Context. At pasture, the nutritional status of mares will change due to a dynamic association between their energy requirements and the energy supply. Change in the plane of nutrition can influence reproductive performance measures in the mares. To help optimise nutritional and operational management of mares on stud farms, the nutritional status of Thoroughbred broodmares and the factors influencing the energy supply and demand were investigated. Aims. To assess nutritional status of the Thoroughbred broodmare herds under ‘normal’ New Zealand commercial stud-farm conditions. Methods. The energy intake, energy requirement and energy balance during the last 3 months of pregnancy and the first 5 months of lactation were modelled for mares with an initial bodyweight of 450 kg, 500 kg, 550 kg and 600 kg, and foaled at 0, 15, 50, and 90 days after 1 September. Key results. For all Foaling dates and bodyweights, mares were in positive energy balance during the last 3 months of pregnancy (6.1–8.5%). Energy balance decreased as pregnancy progressed, followed by a large and acute energy deficit that was initiated soon after Foaling and continued during lactation. The energy deficit during lactation varied between –8.6% and –12.4%, depending on the Foaling date modelled. Mares Foaling later in the season (50–90 days after 1 September) had greater and longer (30–50 days) postpartum energy deficit than did mares that foaled earlier in the season, who recovered within 20 days postpartum. The modelled changes in the energy balance would be large enough to initiate mobilisation of the fat reserve (body condition), and could, therefore, explain the observation of delayed postpartum to conception interval observed with later-Foaling mares on commercial farms. Conclusions. There is a large and prolonged energy deficit soon after Foaling and throughout 150 days of lactation in Thoroughbred mares managed under New Zealand commercial grazing conditions. Foaling later in the season can cause a mismatch in energy supply and demand that would increase and prolong the energy deficit. Implications. These findings suggest a need for stud farms to actively manage the pasture supply and monitor the mare’s BWT and BCS changes in an attempt to optimise the mare’s nutritional status and reproductive performance.
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gestation length and occurrence of daytime Foaling of standardbred mares on two stud farms in new zealand
New Zealand Veterinary Journal, 2012Co-Authors: M Dicken, E K Gee, C W Rogers, I G MayhewAbstract:Abstract AIMS: To examine the gestation lengths and occurrence of daytime Foaling of Standardbred mares Foaling outdoors at stud farms in Southland, New Zealand (latitude 45˚S). METHODS: Data were collected prospectively at two commercial Standardbred stud farms (Farms A and B), during the 2008/9 and 2009/10 breeding seasons (October to February). For each Foaling, the identity of the mare, date and time of Foaling, gender of foal, time the mare passed the fetal membranes, time the foal stood, and Foaling problems including dystocias, were recorded. The effect of farm, season, gender of foal, month of artificial insemination (AI) or Foaling, age and parity of mare on gestation length, percentage of mares Foaling during daylight hours, and percentage of Foalings recorded as dystocia, were examined. RESULTS: A total of 614 Foaling records were obtained from 507 mares. For 594 Foalings with complete records, mean gestation length was 349 (SE 0.5) days. Mean gestation length was shorter for fillies (347.8 (SE...
Dongxiao Zhang - One of the best experts on this subject based on the ideXlab platform.
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effects of solids retention time on the performance and microbial community structures in membrane bioreactors treating synthetic oil refinery wastewater
Chemical Engineering Journal, 2018Co-Authors: Yinhai Yang, Bin Yang, Xingwang Zhang, Yang Hou, Lecheng Lei, Dongxiao ZhangAbstract:Abstract The treatment of oil refinery wastewater has attracted a significant attention for containing hazardous pollutants and causing adverse impacts on the environment. Three submerged membrane bioreactors (MBRs) treating synthetic oil refinery wastewater containing aromatic hydrocarbons including toluene and anthracene were operated at the different solids retention times (SRT) (10, 30 and 60 days) to investigate pollutants removals and membrane fouling characteristics. Mycobacterium and Sphingomonas capable of degrading aromatic compounds found in MBRs may contribute to high removal efficiencies (>99%) of aromatic hydrocarbons at three SRTs. It is observed that nitrifying bacteria at short SRT of 10 days was in low abundance, and the resulting removal efficiency of NH 4 + -N was only 79%, which is much lower than those in MBRs at the SRTs of 30 and 60 days (>97%). Severe membrane fouling and the minimal membrane fouling was observed at the SRT of 10 and 30 days respectively. Additionally, the investigation of loosely bound extracellular polymeric substances (LB-EPS) content including the protein and polysaccharide induced by SRT indicated that high LB-EPS concentration at the SRT of 10 days caused severe membrane fouling. The relative abundances of the biofilm-forming bacteria Deinococcus and the bulking and foaming bacteria Caldilineaceae found in three MBRs correlated well with membrane fouling rate.