Selective dry cow therapy effect on milk yield and somatic cell count: A retrospective cohort study

Peer reviewe

Economic perspectives on blanket and selective dry cow therapy

Peer reviewe

Tuotos, hedelmällisyys, hoidot ja poistot tavanomaisissa ja luomulypsykarjoissa 1998 - 2002

Tämän tutkimuksen tavoitteina oli 1) määritellä lypsykarjojen tuotokseen ja hedelmällisyyden hallinnan tunnuslukuihin vaikuttavat karjatason muuttujat tavanomaisessa ja luomutuotannossa, 2) kuvailla lehmillä yleisimpien sairauksien hoitoprosentteja ja poistonsyitä, ja 3) vertailla eroja tuotantosuuntien välillä. Tutkimusaineistona käytettiin 1226 tavanomaisen ja 109 luomutilan karjantarkkailutietoja vuosilta 1998–2002. Aineistoa analysoitiin lineaaristen mixed-mallien avulla. Karjojen keskituotos kasvoi tarkastelujaksolla luomutuotannossa 6822:sta 7422:een, ja tavanomaisessa 7426:sta 8206 kiloon, ollen luomukarjoissa keskimäärin 688 kg alhaisempi. Keskituotoksesta muualle kuin meijeriin päätyi keskimäärin 9,3%. Poistettujen lehmien elinikäistuotos kasvoi luomutuotannossa keskimäärin 18 491:stä 19 849:ään ja tavanomaisessa 19 751:stä 22 073 kiloon. Luomutuotannossa se oli keskimäärin 2050kg tavanomaista alhaisempi.Lehmien poistoiässä tai poiston syissä ei ollut merkittäviä eroja tuotantosuuntien välillä. Erot hedelmällisyyden hallinnan tunnusluvuissa tuotantosuuntien välillä olivat merkityksettömiä. Luomukarjoissa kaikkien tarkasteltujen sairauksien hoitoprosentit olivat tavanomaisia alhaisempi

Dry cow therapy and early lactation udder health problems - Associations and risk factors

Mastitis remains the most expensive disease of dairy cows, and antibiotic dry cow therapy (DCT) at dry-off is an important part of mastitis control. Regardless of the infection status, blanket DCT is administered to all quarters of all cows, which is controversial due to the worldwide problem of antimicrobial resistance. Even though selective DCT of only infected cows is a more sustainable approach, choosing animals for treatment is not always straightforward. Our aim was to evaluate whether the herd-level DCT approach is associated with early lactation udder health problems, taking into account the cow characteristics. The information source was 2015?2017 Dairy Herd Improvement data with 7461 multiparous cows from 241 Finnish dairy herds. Information on the herd-level DCT approach was obtained from farmers? questionnaire responses in 2017, and the three different approaches were selective DCT, blanket DCT, and no DCT. The statistical tool for the data analysis was a generalized linear mixed model with a random herd effect for binary outcomes and a linear mixed model with a random herd effect for a continuous outcome. The two binary outcomes were the odds of having high milk somatic cell count (SCC ? 200 000 cells/mL) on the first test-day within 5?45 days in milk (DIM) and the odds of mastitis treatment in early lactation up to 45 DIM. The third outcome was the mean milk lnSCC (? 1000 cells/ mL) within 120 DIM. Selective DCT was the prevailing treatment practice in our data. Blanket DCT was associated with lower SCC after calving. Cows more likely to have high SCC after calving were older cows, cows with high average SCC during the previous lactation, and cows with high milk yield near dry-off. A mastitis treatment in the early lactation was more likely if, during the previous lactation, the cow had high average SCC, high peak milk production, or high milk yield near dry-off. Our findings indicate that DCT is still effective in mastitis control. Cows with high milk yield, especially near dry-off, and cows with persistently high SCC require attention when considering next lactation udder health.Mastitis remains the most expensive disease of dairy cows, and antibiotic dry cow therapy (DCT) at dry-off is an important part of mastitis control. Regardless of the infection status, blanket DCT is administered to all quarters of all cows, which is controversial due to the worldwide problem of antimicrobial resistance. Even though selective DCT of only infected cows is a more sustainable approach, choosing animals for treatment is not always straightforward. Our aim was to evaluate whether the herd-level DCT approach is associated with early lactation udder health problems, taking into account the cow characteristics. The information source was 2015?2017 Dairy Herd Improvement data with 7461 multiparous cows from 241 Finnish dairy herds. Information on the herd-level DCT approach was obtained from farmers? questionnaire responses in 2017, and the three different approaches were selective DCT, blanket DCT, and no DCT. The statistical tool for the data analysis was a generalized linear mixed model with a random herd effect for binary outcomes and a linear mixed model with a random herd effect for a continuous outcome. The two binary outcomes were the odds of having high milk somatic cell count (SCC ? 200 000 cells/mL) on the first test-day within 5?45 days in milk (DIM) and the odds of mastitis treatment in early lactation up to 45 DIM. The third outcome was the mean milk lnSCC (? 1000 cells/ mL) within 120 DIM. Selective DCT was the prevailing treatment practice in our data. Blanket DCT was associated with lower SCC after calving. Cows more likely to have high SCC after calving were older cows, cows with high average SCC during the previous lactation, and cows with high milk yield near dry-off. A mastitis treatment in the early lactation was more likely if, during the previous lactation, the cow had high average SCC, high peak milk production, or high milk yield near dry-off. Our findings indicate that DCT is still effective in mastitis control. Cows with high milk yield, especially near dry-off, and cows with persistently high SCC require attention when considering next lactation udder health.Peer reviewe

Antimicrobial susceptibility of staphylococci from bovine milk samples in routine microbiological mastitis analysis in Finland

The most frequent reason for antimicrobial use in dairy herds is mastitis and knowledge about mastitis-causing pathogens and their antimicrobial susceptibility should guide treatment decisions. The overall objective of this study was to assess antimicrobial resistance (AMR) of staphylococci in mastitic milk samples in Finland. MALDI-ToF MS identified a total of 504 Staphylococcus isolates (260 S. aureus and 244 non-aureus staphylococci, NAS) originating from bovine mastitic milk samples. Phenotypic susceptibility against cefoxitin, ceftiofur, enrofloxacin, gentamycin, oxacillin, penicillin, and tetracycline was evaluated by disk diffusion method and the presence of blaZ, mecA, and mecC genes investigated by PCR. Nitrocefin test assessed these isolates’ beta-lactamase production. The most common NAS species were S. simulans, S. epidermidis, S. chromogenes, and S. haemolyticus. In total, 26.6% of the isolates (18.5% of S. aureus and 35.2% of all NAS) carried the blaZ gene. Penicillin resistance, based on disk diffusion, was lower: 18.8% of all the isolates (9.3% of S. aureus and 28.9% of all NAS) were resistant. Based on the nitrocefin test, 21.5% of the isolates produced beta-lactamase (11.6% of S. aureus and 32.0% of all NAS). Between the Staphylococcus species, the proportion of penicillin-resistant isolates varied, being lowest in S. simulans and highest in S. epidermidis. Resistance to antimicrobials other than penicillin was rare. Of the eight NAS isolates carrying the mecA gene, six were S. epidermidis. One S. aureus isolate carried the mecC gene. Agreement beyond chance, assessed by kappa coefficient, between phenotypic and genotypic resistance tests, was moderate to substantial. Some phenotypically penicillin-susceptible staphylococci carried the blaZ gene but isolates without blaZ or mec genes rarely exhibited resistance, suggesting that the more reliable treatment choice may depend upon genotypic AMR testing. Our results support earlier findings that penicillin resistance is the only significant form of antimicrobial resistance among mastitis-causing staphylococci in Finland

Prototheca spp. naudan utaretulehduksen aiheuttajana : kirjallisuuskatsaus ja tapausselostus kolmesta karjaongelmasta

Lypsylehmien utaretulehdus heikentää eläinten hyvinvointia sekä tuotannon taloudellisuutta. Prototheca spp. -levät elävät kosteissa ympäristöissä ja kykenevät muodostamaan pinnoille biofilmejä. Prototekan aiheuttama utaretulehdus on harvinainen mutta yleistynyt viime vuosina. Useimmiten aiheuttajana on Prototheca bovis. Prototekan taudinaiheutus perustuu kudosinvaasioon. Tulehdus voi olla paikallinen, jolloin lehmällä ei ole yleisoireita, mutta maito voi muuttua vetiseksi tai utare turvonneeksi ja kovaksi. Toisinaan prototeka aiheuttaa akuutin kuumeisen utaretulehduksen. Useimmiten tulehdukset ovat lieviä tai kohtalaisia. Prototeka-utaretulehdukseen ei ole tehokasta hoitoa, joten vaihtoehdoiksi jäävät erilleen lypsy, infektoituneen neljänneksen umpeutus tai lehmän poisto. Ehkäisyssä on tärkeää huolehtia lypsyhygieniasta sekä ympäristön puhtaudesta. Osa prototeka-lajeista on zoonoottisia ja ne aiheuttavat tyypillisimmin ihmiselle iho-oireita. Kolmella suomalaisella lypsykarjatilalla prototeka-utaretulehdukset olivat muodostuneet karjaongelmaksi ja niille tehtiin ongelmanselvityskäynnit. Käynneillä otetuista ympäristönäytteistä löytyi PCR-menetelmällä Prototheca spp. useista kohteista. Tiloille annettiin toiminnan parannusehdotuksia. Kahdella tilalla prototekan aiheuttamat utaretulehdukset loppuivat ja yhdellä niiden määrä väheni.Peer reviewe

Antibiotic dry cow therapy, somatic cell count, and milk production : Retrospective analysis of the associations in dairy herd recording data using multilevel growth models

Antibiotic dry cow therapy (DCT) is an important part of most mastitis control programs. Updating DCT recommendations is an ongoing topic due to the global problem of antimicrobial resistance. Finland, along with other Nordic countries, has implemented selective DCT for decades. Our study analyzed Dairy Herd Improvement (DHI) information from 241 Finnish farmers who participated in a survey about their drying-off practices. The aim was to evaluate herd-level associations between milk somatic cell count (SCC), milk production, and various antimicrobial DCT approaches both cross-sectionally in 2016 and longitudinally in 2012 - 2016. The three DCT approaches in the study were selective, blanket, and no DCT use. An additional aim was to evaluate whether dynamic changes occurred in herd-average SCC and annual milk production over five years, and whether these potential changes differed between different DCT approaches. The method for the longitudinal analyses was growth modeling with random coefficient models. Differences in SCC and milk production between farms with different DCT approaches were minor. Regardless of the farm's DCT approach, annual milk production increased over the years, while average SCC was reasonably constant. The variability in SCC and milk production across all DCT groups was low between years, and most of the variability was between farms. Compared to other milking systems, farms with automatic milking system (AMS) had higher SCC, and in 2016 higher milk production. The results of this study suggest that it is possible to maintain low herd-average SCC and good milk production when using selective DCT and following the guidelines for prudent antimicrobial use. Average SCC and milk production varied across the herds, suggesting that advice on DCT practices should be herd-specific. The methodology of growth modeling using random coefficient models was applicable in analyzing longitudinal data, in which the time frame was relatively short and the number of herds was limited.Peer reviewe

Maailman halutuinta maitoa Suomesta - Lypsykarjatalouden tutkimuksen strategia 2018 - 2025

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The Impact of Overstocking and Negative Energy Balance on Quantitative Measurement of Non-typhoidal Salmonella in Periparturient Dairy Cattle

Stressful conditions in animal production facilities may exacerbate the fecal shedding and foodborne transmission of non-typhoidal Salmonella enterica subsp. enterica. Dairy cows are reservoirs of this zoonotic microorganism, and its prevalence has roughly doubled in the past decade on dairy farms in United States. Dairy cows are commonly overstocked at the feed bunk, and stressors placed on the animal prior to parturition may exacerbate Salmonella shedding. However, no studies have evaluated the impact of overstocking and metabolic stress on fecal concentrations of the pathogen. Therefore, we conducted a field trial with 120 multiparous dairy cows randomized into one of four treatment groups with different stocking densities at the feed bunk during the periparturient period as follows: US, understocked from -60 to -1 DRC; OS, overstocked from -60 to -1 DRC; USOS, understocked from -60 to -26 DRC/overstocked from -25 to -1 DRC; and OSUS, overstocked from -60 to -26 DRC/ understocked from -25 to -1 DRC. Fecal and blood samples were collected at four time points relative to calving. qPCR assays were used to quantify Salmonella invA gene and total bacterial community from fecal samples, and a subset of isolates recovered from fecal bacterial culture were characterized using pulsed field gel electrophoresis and serotyping. Serum non-esterified fatty acids (NEFA) were measured as a metabolic stress indicator using an immunoassay. Multivariable analyses were performed to test if changes in Salmonella concentrations were associated with stocking density, energy balance, or days relative to calving. From fecal isolates, three Salmonella serovars were identified, S. Cerro; Kentucky; Meleagridis. Concentrations of Salmonella increased as cows approached calving. Higher stocking densities at the feed bunk did not impact total bacterial community or NEFA; however, cows in the overstocked groups had higher Salmonella fecal concentrations. Further, cows with higher NEFA concentrations after calving had a higher likelihood of detection of Salmonella. Future farm interventions should aim to reduce environmental and metabolic stress during the periparturient period to decrease the dissemination of Salmonella to cattle, the environment, and humans.Peer reviewe