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S T Butler - One of the best experts on this subject based on the ideXlab platform.

  • expanding the dairy Herd in pasture based systems the role of sexed semen use in virgin heifers and lactating cows
    Journal of Dairy Science, 2013
    Co-Authors: I A Hutchinson, L Shalloo, S T Butler
    Abstract:

    A model was developed to examine the effects of sexed semen use in virgin heifers and lactating cows on replacement heifer numbers and rate of Herd expansion in a seasonal dairy production system. Five separate Herds were established according to the type of semen used: conventional frozen-thawed (Conv), sexed fresh semen used in lactating cows for the first 3 wk of the breeding season (SFre1), sexed frozen-thawed semen used in lactating cows for the first 3 wk of the breeding season (SFro1), sexed fresh semen used in lactating cows for the first 6 wk of the breeding season (SFre2), or sexed frozen-thawed semen used in lactating cows for the first 6 wk of the breeding season (SFro2). In the SFro1, SFre1, SFro2, and SFre2 Herds, sexed semen was used for the first and second artificial insemination in virgin heifers. Pregnancy rates achieved with sexed fresh and sexed frozen-thawed semen were assumed to be 94 and 75% of those achieved with conventional frozen-thawed semen, respectively. Initial Herd Size was 100 cows, which was maintained for the first 2 yr of the 15-yr simulation, after which all available replacement heifers were retained to facilitate Herd expansion. Two different scenarios of land availability were examined for each of the 5 Herds: land available allowed expansion to a maximum Herd Size of 150 cows (S1), or land available allowed expansion to a maximum Herd Size of 300 cows (S2). Once maximum Herd Size was reached, sexed semen use was discontinued and all excess heifer calves were sold at 1 mo old. All capital expenditure associated with expansion was financed with a 15-yr loan. Each of the 10 different options was evaluated in terms of annual farm profit, annual cash flow, and total discounted net profit. The use of fresh sexed semen generated more replacement heifers, leading to faster Herd expansion compared with frozen-thawed sexed semen and conventional frozen-thawed semen. Maximum Herd Size under S1 was reached in yr 5, 5, 4, 5, and 7 for the SFre1, SFro1, SFre2, SFro2, and Conv Herds, respectively. Under S2, maximum Herd Size was reached in yr 8, 10, 7, 9, and 14 for the SFre1, SFro1, SFre2, SFro2, and Conv Herds, respectively. Total discounted net profit under S1 for the SFre2 Herd was €4,130, €38,869, €47,231, and €52,089 greater compared with the SFre1, SFro1, Conv, and SFro2 Herds, respectively. Under S2, discounted net profit for the SFre2 Herd was €44,204, €255,524, €280,373, and €325,815 greater compared with the SFre1, SFro1, SFro2, and Conv Herds, respectively. The negative effects of the sexed frozen-thawed semen on Herd fertility reduced farm profitability and will prevent its widespread use in lactating cows.

  • expanding the dairy Herd in pasture based systems the role for sexed semen use on virgin heifers
    Journal of Dairy Science, 2013
    Co-Authors: I A Hutchinson, L Shalloo, S T Butler
    Abstract:

    A model was developed to examine the effects of sexed semen use on replacement heifer numbers and rate of Herd expansion in a seasonal dairy production system. Three separate Herds were established according to the type of semen used on virgin heifers: conventional frozen-thawed (Conv), sexed fresh (SFre), or sexed frozen-thawed (SFro). In the model, sexed semen was used for the first and second inseminations in heifers only. Pregnancy rates achieved with sexed fresh and sexed frozen-thawed semen were assumed to be 94% and 75% of those achieved with conventional frozen-thawed semen, respectively. Initial Herd Size was 100 cows, which was maintained for the first 2 yr of the 15-yr simulation, after which all available replacement heifers were retained to facilitate Herd expansion. Two different scenarios of land availability (S1 and S2) were examined for each of the 3 Herds using different semen types: land available allowed expansion to a maximum Herd Size of 150 cows (S1) or 300 cows (S2). Once maximum Herd Size was reached, sexed semen use was discontinued and all excess heifer calves were sold at 1 mo of age. All capital expenditure associated with expansion was financed with a 15-yr loan. Each of the different options was evaluated in terms of annual farm profit, annual cash flow, and total discounted net profit. The analysis was completed at a milk price of € 0.27/L, and sensitivity around milk price was carried out at € 0.22/L and € 0.32/L. The use of SFre generated more replacement heifers and thus faster Herd expansion compared with SFro and Conv semen. Maximum Herd Size was reached in yr 5, 6, and 7 under S1, and in yr 10, 12, and 14 under S2 for SFre, SFro, and Conv Herds, respectively. Total discounted net profit under S1 for the SFre Herd was € 19,929 greater than that of the SFro Herd and € 41,852 greater than that of the Conv Herd. Under S2, discounted net profit for the SFre Herd was € 138,587 greater than that of the SFro Herd and € 239,987 greater than that of the Conv Herd. All 3 Herds suffered negative cash flows for extended periods under both S1 and S2 at the lower milk price of € 0.22/L, although cash flows were most negative in the SFre Herd. The use of sexed semen, in particular fresh sexed semen, in dairy heifers facilitates faster and more profitable expansion compared with the use of conventional frozen-thawed semen. Financial pressures caused by low milk price were greatest when the rate of expansion was highest.

H W Barkema - One of the best experts on this subject based on the ideXlab platform.

  • environmental sample characteristics and Herd Size associated with decreased Herd level prevalence of mycobacterium avium ssp paratuberculosis
    Journal of Dairy Science, 2018
    Co-Authors: Caroline S Corbett, Ali S Naqvi, Jeroen De Buck, Uliana Kanevets, J P Kastelic, H W Barkema
    Abstract:

    Environmental sampling is an effective method for estimating regional dairy Herd-level prevalence of infection with Mycobacterium avium ssp. paratuberculosis (MAP). However, factors affecting prevalence estimates based on environmental samples are not known. The objective was to determine whether odds of environmental samples collected on farm changed culture status over 2 sampling times and if changes were specific for location and type of housing (freestall, tiestall, or loose housing), the sample collected (i.e., manure of lactating, dry, or sick cows; namely, cow group), and effects of Herd Size. In 2012-2013 [sampling 1 (S1)] and 2015-2017 [sampling 2 (S2)], 6 environmental samples were collected and cultured for MAP from all 167 (99%) and 160 (95%) farms, respectively, in the province of Saskatchewan, Canada. Only the 148 dairy farms sampled at both sampling periods were included in the analysis. A mixed effects logistic regression was used to determine whether differences between sampling periods were associated with Herd Size and sample characteristics (cow group contributing to environmental sample, type of housing, and location). In S1 and S2, 55 and 34%, respectively, of farms had at least 1 MAP-positive environmental sample. Correcting for sensitivity of environmental sampling, estimated true prevalence in S1 and S2 was 79 and 48%, respectively. Herds with >200 cows were more often MAP-positive than Herds with 200 cows more frequently stayed MAP-positive. No difference was observed in the odds of a sample being MAP-positive among housing types or location of sample collection in both sample periods. Of all farms sampled, 104 (70%) did not change status from S1 to S2. In conclusion, when Herd-level MAP prevalence decreased over the 3-yr interval, the change in prevalence differed among Herd Size categories and was larger in samples from dry cow areas. It was, however, not specific to other characteristics of environmental samples collected.

  • sampling location Herd Size and season influence mycobacterium avium ssp paratuberculosis environmental culture results
    Journal of Dairy Science, 2015
    Co-Authors: Robert Wolf, Jeroen De Buck, H W Barkema, Karin Orsel
    Abstract:

    Mycobacterium avium subspecies paratuberculosis (MAP), the etiologic agent of Johne's disease, a chronic progressive enteritis, is a common pathogen on dairy farms. Environmental sampling is frequently used to detect MAP-infected Herds, because it does not require sample collection from individual animals. The objectives were to determine (1) location-specific odds of MAP-positive environmental sampling results and whether season or Herd Size affect results; (2) whether season and Herd Size affect the odds of collection of samples from certain locations; and (3) whether sample-set composition affects the odds of a positive set. Herd veterinarians, producer organization staff, and University of Calgary staff collected 5,588 samples on dairy farms in Alberta and Saskatchewan. Samples from sick-cow and calving pens and samples from dry-cow housing had lower odds of testing MAP-positive than lactating cow-pen samples (odds ratio=0.3 and 0.4, respectively). Samples collected from bedding packs and manure piles were less frequently MAP-positive than those collected from alleyways and lagoons, whereas samples collected in spring and summer more often tested MAP-positive than those collected in winter. Sample sets collected in summer more often included samples from all locations than samples collected in winter; therefore, we inferred that collectors had difficulties accessing certain areas in winter. Substitution of sample locations with others had minor effect on the sensitivity of sample sets containing 6 samples. However, set composition had an effect on the sensitivity of sample sets containing only 2 samples. In that regard, whereas sets with 2 manure-storage-area samples detected 81% of farms with at least one positive environmental sample, sets with only dry, sick, or calving-pen samples detected only 59%. Environmental samples should be collected from areas where manure from numerous cows accumulates and can be well mixed (e.g., alleyways and manure lagoons). Collection of samples should be performed in spring or summer when locations are easier to access and samples have higher odds for testing MAP-positive.

I A Hutchinson - One of the best experts on this subject based on the ideXlab platform.

  • expanding the dairy Herd in pasture based systems the role of sexed semen use in virgin heifers and lactating cows
    Journal of Dairy Science, 2013
    Co-Authors: I A Hutchinson, L Shalloo, S T Butler
    Abstract:

    A model was developed to examine the effects of sexed semen use in virgin heifers and lactating cows on replacement heifer numbers and rate of Herd expansion in a seasonal dairy production system. Five separate Herds were established according to the type of semen used: conventional frozen-thawed (Conv), sexed fresh semen used in lactating cows for the first 3 wk of the breeding season (SFre1), sexed frozen-thawed semen used in lactating cows for the first 3 wk of the breeding season (SFro1), sexed fresh semen used in lactating cows for the first 6 wk of the breeding season (SFre2), or sexed frozen-thawed semen used in lactating cows for the first 6 wk of the breeding season (SFro2). In the SFro1, SFre1, SFro2, and SFre2 Herds, sexed semen was used for the first and second artificial insemination in virgin heifers. Pregnancy rates achieved with sexed fresh and sexed frozen-thawed semen were assumed to be 94 and 75% of those achieved with conventional frozen-thawed semen, respectively. Initial Herd Size was 100 cows, which was maintained for the first 2 yr of the 15-yr simulation, after which all available replacement heifers were retained to facilitate Herd expansion. Two different scenarios of land availability were examined for each of the 5 Herds: land available allowed expansion to a maximum Herd Size of 150 cows (S1), or land available allowed expansion to a maximum Herd Size of 300 cows (S2). Once maximum Herd Size was reached, sexed semen use was discontinued and all excess heifer calves were sold at 1 mo old. All capital expenditure associated with expansion was financed with a 15-yr loan. Each of the 10 different options was evaluated in terms of annual farm profit, annual cash flow, and total discounted net profit. The use of fresh sexed semen generated more replacement heifers, leading to faster Herd expansion compared with frozen-thawed sexed semen and conventional frozen-thawed semen. Maximum Herd Size under S1 was reached in yr 5, 5, 4, 5, and 7 for the SFre1, SFro1, SFre2, SFro2, and Conv Herds, respectively. Under S2, maximum Herd Size was reached in yr 8, 10, 7, 9, and 14 for the SFre1, SFro1, SFre2, SFro2, and Conv Herds, respectively. Total discounted net profit under S1 for the SFre2 Herd was €4,130, €38,869, €47,231, and €52,089 greater compared with the SFre1, SFro1, Conv, and SFro2 Herds, respectively. Under S2, discounted net profit for the SFre2 Herd was €44,204, €255,524, €280,373, and €325,815 greater compared with the SFre1, SFro1, SFro2, and Conv Herds, respectively. The negative effects of the sexed frozen-thawed semen on Herd fertility reduced farm profitability and will prevent its widespread use in lactating cows.

  • expanding the dairy Herd in pasture based systems the role for sexed semen use on virgin heifers
    Journal of Dairy Science, 2013
    Co-Authors: I A Hutchinson, L Shalloo, S T Butler
    Abstract:

    A model was developed to examine the effects of sexed semen use on replacement heifer numbers and rate of Herd expansion in a seasonal dairy production system. Three separate Herds were established according to the type of semen used on virgin heifers: conventional frozen-thawed (Conv), sexed fresh (SFre), or sexed frozen-thawed (SFro). In the model, sexed semen was used for the first and second inseminations in heifers only. Pregnancy rates achieved with sexed fresh and sexed frozen-thawed semen were assumed to be 94% and 75% of those achieved with conventional frozen-thawed semen, respectively. Initial Herd Size was 100 cows, which was maintained for the first 2 yr of the 15-yr simulation, after which all available replacement heifers were retained to facilitate Herd expansion. Two different scenarios of land availability (S1 and S2) were examined for each of the 3 Herds using different semen types: land available allowed expansion to a maximum Herd Size of 150 cows (S1) or 300 cows (S2). Once maximum Herd Size was reached, sexed semen use was discontinued and all excess heifer calves were sold at 1 mo of age. All capital expenditure associated with expansion was financed with a 15-yr loan. Each of the different options was evaluated in terms of annual farm profit, annual cash flow, and total discounted net profit. The analysis was completed at a milk price of € 0.27/L, and sensitivity around milk price was carried out at € 0.22/L and € 0.32/L. The use of SFre generated more replacement heifers and thus faster Herd expansion compared with SFro and Conv semen. Maximum Herd Size was reached in yr 5, 6, and 7 under S1, and in yr 10, 12, and 14 under S2 for SFre, SFro, and Conv Herds, respectively. Total discounted net profit under S1 for the SFre Herd was € 19,929 greater than that of the SFro Herd and € 41,852 greater than that of the Conv Herd. Under S2, discounted net profit for the SFre Herd was € 138,587 greater than that of the SFro Herd and € 239,987 greater than that of the Conv Herd. All 3 Herds suffered negative cash flows for extended periods under both S1 and S2 at the lower milk price of € 0.22/L, although cash flows were most negative in the SFre Herd. The use of sexed semen, in particular fresh sexed semen, in dairy heifers facilitates faster and more profitable expansion compared with the use of conventional frozen-thawed semen. Financial pressures caused by low milk price were greatest when the rate of expansion was highest.

Matthias Gauly - One of the best experts on this subject based on the ideXlab platform.

  • relationship between Herd Size and measures of animal welfare on dairy cattle farms with freestall housing in germany
    Journal of Dairy Science, 2018
    Co-Authors: Daniel Gieseke, Christian Lambertz, Matthias Gauly
    Abstract:

    ABSTRACT The objective of this study was to examine the association of Herd Size with animal welfare in dairy cattle Herds. Therefore, 80 conventional dairy cattle farms were classified by the number of cows into 4 Herd Size classes, C1 (

  • How can working time analysis contribute to the production efficiency of dairy farms in mountain regions?
    Taylor & Francis Group, 2018
    Co-Authors: Ioanna Poulopoulou, Martin Christian Nock, Silvia Steinmayer, Christian Lambertz, Matthias Gauly
    Abstract:

    The aim of the present study was to (1) estimate the labour input on loose and tie stall housing dairy farms in South Tyrol; (2) to develop a tool for the extension service available to propose strategies for improving labour productivity. The study performed on 102 dairy farms, half of them with tie and half with loose housing. Daily and non-daily working activities surveyed with a questionnaire. Nine tie stall and 10 loose housing farms were selected for on-site measurements to determine the working time of each activity and validate questionnaire data. Average Herd Size was 16.3 and 23.2 cows for tie stall and loose housing farms, respectively. Effects of housing type and Herd Size category on total and single working time were examined. In tie stalls and Herd Size 21 cows required 82 MPh/cow/year. Labour costs were estimated as 34.9 and 19.2 Euro cents per kg of milk for tie and loose housing, while milk production per working hour determined as 56.9 and 86.7 kg/MPh, respectively. The required MPh/cow/year decreased as the Herd Size increased. Efficient organisation of working time with an increase in Herd Size might improve production efficiency and sustainability of mountain dairy farming. However, it has to be taken into consideration that because of limited space and the fact that most farmers are only working part time on farm, the improvement of labour management is of higher importance

Ulf Emanuelson - One of the best experts on this subject based on the ideXlab platform.

  • Herd level risk factors associated with cow mortality in swedish dairy Herds
    Journal of Dairy Science, 2012
    Co-Authors: Karin Alvasen, Jansson M Mork, Hallen C Sandgren, Peter T Thomsen, Ulf Emanuelson
    Abstract:

    Abstract An increase in on-farm mortality (euthanasia and death) in dairy Herds has been reported in several countries in the last decade. This does not only imply possible problems with animal welfare, but it also causes economic losses to the farmer. The objective of this study was to evaluate time trends in on-farm dairy cow mortality in Sweden and identify potential Herd-level risk factors. Data were retrieved on all Swedish dairy Herds enrolled in the milk recording scheme between 2002 and 2010. Herds with a Herd Size of 40 dead or euthanized cows per 100 cow-years were excluded. Two different models were used: 1 multiple-year analysis, which included 6,898 Herds during the period 2002 to 2010 and 1 single-year analysis including 4,252 Herds for the year 2010, where other variables that were not present during the entire multiple year study were analyzed. The outcome variable was the number of euthanized and dead cows per year and season. A negative binomial regression model, adjusted for clustering within Herd, was applied to both models. Fixed effects in the multiple-year analysis were breed, calving interval, Herd Size, milk yield, region, season, pasture period, and year. The fixed effects in the single-year analysis were breed, calving interval, conventional versus organic farming, Herd Size, housing system, milk yield, region, and season. The results demonstrated that MR gradually increased from 5.1 to 6.6 events per 100 cow-years during the study period. Swedish MR are consequently on par with, or even greater than, MR among dairy Herds in other comparable countries. Higher mortality was associated with larger Herd Size, longer calving intervals, and Herds that had Swedish Holstein as the predominant breed. Lower mortality was observed in Herds with a higher Herd average milk yield, during the fall and winter, and in organically managed Herds. There were regional differences in mortality. An interaction between Herd Size and season was found in both models. Also, an interaction between housing system and milk yield was found in the single-year analysis. This first assessment of on-farm mortality in Swedish dairy Herds confirmed that the MR has increased over the last few years. The study also identified some Herd-level risk factors.