Vitamins and selenium in bulk tank milk of organic and conventional dairy farms

Vitamins in milk are important for the human consumer, the calf and the cow. They are also important for the dairy industry because some of them affect the risk for off-flavour. Studies indicate that milk from organic and conventional dairy farms may differ in these aspects. The aim of this study was therefore to investigate whether there are differences in the concentration of vitamins and selenium in milk between organic and conventional farms in Sweden. Bulk tank milk was sampled in 20 organic and 20 conventional dairy farms at three occasions during the indoor season. Concentrations of α-tocopherol, β-carotene and retinol were determined by HPLC and selenium by hydrid generation inductively coupled plasma atomic emission spectrometry. Herd characteristics were collected by questionnaires and from the official milk recording scheme. Multivariable linear mixed models were used to evaluate the associations between milk composition and type of farm, while adjusting for potential confounders and the repeated observations within farm. Average levels of α-tocopherol, β-carotene, retinol and selenium were 0.84 µg/ml, 0.18 µg/ml, 0.32 µg/ml and 13.6 µg/kg, respectively. There were no differences between organic and conventional farms in β-carotene, retinol or selenium concentration. Concentration of α-tocopherol was also similar, but was significantly lower in organic farms if differences in amount of roughage were accounted for in the statistical model

Health and reproduction in organic and conventional swedish dairy cows

This thesis compares indicators of animal health and reproduction in organically and conventionally managed dairy cows in Sweden. The first part of the thesis is based on data from a twelve-year longitudinal study of a research farm with parallel but separate organic and conventional management. The second part of the thesis is based on data from a field investigation performed by the author. The field investigation included 20 organically and 20 conventionally managed dairy herds in south-east Sweden. Udder health and reproductive performance were studied in both the research farm and in the field study, general health and length of productive life in the research farm only and early-lactation metabolic profiles in the field study only. Udder health was assessed by comparing somatic cell counts during first 150 days in milk, number of test-milking occasions with >200,000 cells/ml during first 150 days in milk and number of veterinary treated cases of mastitis. Reproductive performance was assessed by comparing calving interval, calving-to-first insemination and pregnancy success at first insemination. Body condition score and blood metabolites indicating negative energy balance such as non-esterified fatty acids, beta-hydroxybutyrate, glucose and insulin were measured. Multivariable, multilevel statistical models were consistently employed. Management type, breed, housing, parity, and milk yield were frequently used predictor variables in the different statistical models. The predictor variable of main interest, organic or conventional management, was forced to stay in all models. The conclusion is that under Swedish conditions, cows in organic and conventional dairy management differ only marginally considering mastitis, reproductive performance and metabolic profiles, implying that animal health in organic management is equally good as in conventional management in these specific fields

Assessing short-term economic consequences of cow-calf contact systems in dairy production using a stochastic partial budgeting approach

Introduction: While early separation of dairy calves after birth has been debated from an ethical and animal welfare lens, the economic evidence surrounding alternative cow-calf contact (CCC) systems is scarce.Methods: To address this knowledge gap, we assessed the economic consequences of CCC systems using data from the Agriwise database as well as parameters from published literature in a stochastic partial budget model. The implementation of CCC is very diverse between farms, so in our study we therefore selected a limited number of CCC systems to assess. The examined CCC systems were: (i) dam rearing with limited contact at milking (15 minutes twice a day for 115 days) with no manual milk feeding; (ii) dam rearing with 21-day full contact, after which calves are manually fed 8 kg of whole milk for 94 days; and (iii) mixed calf rearing with using both dams and foster cows with full contact; calves are initially kept with their dams and then moved to foster cows at 9 days of age.Results: We found that adoption of CCC systems was associated with decreases in contribution margins in the range of 1 to 5.4%, as compared to a rearing system where the calves were separated from their dams after one day and were manually fed 8 kg of milk for 12 weeks. These results illustrated that the costs associated with CCC systems may be fairly high under certain circumstances and may prohibit farmers from adopting this practice. Sensitivity analysis suggested that differences in milk sales, assumptions on changes in labor requirements, and changes in daily calf weight gain depending on CCC system were the main variables that governed the net impact on the contribution margins.Discussion: We did not include building costs in the analyses assuming that barn structures may not change in the short-term. The study focused only on short-term pecuniary associations between changes in CCC systems and contribution margins. To strengthen the economic decision-making around CCC systems, future research should consider non-monetary impacts of different CCC systems, as well as long-term economic impacts of these production strategies

Pågående svenskt projekt: Djurhälsa i ekologiska mjölkbesättningar

I doktorandprojektet ”Djurhälsa i ekologiska mjölkbesättningar” som drivs vid Institutionen för kliniska vetenskaper, Fakulteten för veterinärmedicin och husdjursvetenskap på SLU studeras effekterna av ekologisk drift på hälsa och fruktsamhet i några olika delstudier

Ekomjölk – djurhälsa i ekologiska mjölkbesättningar

Målsättningen med projektet är: • Ökad generell kunskap om hälsoläget i ekologiska besättningar med mjölkproduktion. • Att bedöma om den officiella sjukdomsregistreringen är ett användbart redskap för att följa upp djurhälsan i ekologiska besättningar. • Att studera om en ekologisk foderstat ökar risken för ämnesomsättnings- och fertilitetsstörningar hos mjölkkor. Projektets nuvarande status: Första besättningsbesöken inom delstudie I har genomförts och besök 2 planeras just nu, medan delstudie II och III kommer att initieras inom kort

Bovine respiratory syncytial virus and bovine coronavirus in Swedish organic and conventional dairy herds

Background: Infections with bovine respiratory syncytial virus (BRSV) and bovine coronavirus (BoCV) are endemic to the cattle populations in most countries, causing respiratory and/or enteric disease. It has been demonstrated that herds can remain free from these infections for several years also in high prevalence areas. Organically managed (OM) dairy herds have been shown to have lower seroprevalence of both viruses compared to conventionally managed (CM) herds. The objective of this study was to challenge the hypothesis of a lower occurrence of BRSV and BoCV in OM compared to CM dairy herds. In November 2011, May 2012 and May 2013 milk samples from four homebred primiparous cows were collected in 75 to 65 OM and 69 to 62 CM herds. The antibody status regarding BRSV and BoCV was analysed with commercial indirect ELISAs. Herds were classified as positive if at least one individual sample was positive. Results: The prevalence of positive herds ranged from 73.4% to 82.3% for BRSV and from 76.8% to 85.3% for BoCV among OM and CM herds, over the three sampling occasions. There was no statistically significant difference between OM and CM herds at any sampling occasion. The incidence risk of newly infected herds did not differ statistically between OM and CM herds at any sampling occasion, neither for BRSV nor for BoCV. The incidence of herds turning sero-negative between samplings corresponded to the incidence of newly infected. Bulk tank milk (BTM) samples were also sampled in the herds and analysed. Several herds were negative on individual samples but positive in BTM. Herd-level data on production, health and reproduction were retrieved from VÄXA Sweden and the study herds were representative of the source population. Conclusion: There was no difference in prevalence of or incidence risk for BRSV or BoCV between Swedish OM and CM herds. Because the incidence of herds becoming seropositive was balanced by herds becoming seronegative it should be possible to lower the prevalence of these two infections among Swedish dairy cattle herds if biosecurity is improved

Restrictive but not restricted: perspectives on antimicrobial use and antimicrobial resistance among Swedish dairy veterinarians

Background and aims In Europe, the antimicrobial use (AMU) for food-producing animals has decreased rapidly. However, studies indicate that a too strict policy, with too restrictive AMU, is potentially problematic for veterinarians because it threatens animal welfare and creates tensions between farmers and veterinarians. The AMU in Sweden is among the lowest in Europe, and regulation of AMU in farm animals is strict. The aim of our study was to explore how Swedish veterinarians describe the relations between (1) being restrictive with antibiotics due to the risk of AMR and (2) concerns for animal welfare and/or the veterinarian-client relationship. Methods Semi-structured interviews with 21 veterinarians, working with dairy cattle, were performed. The transcripts were analysed, and a number of dominant patterns which recurred in all, or most of, the interviews were identified. Result The interviewed veterinarians described AMR prevention and tackling the threat AMR poses towards public health, as central for their profession and as influencing their everyday practice and decisions on AMU. Importantly, veterinarians described accounting for AMR in everyday practice as fairly unproblematic, both in relation to animal welfare as well as in relation to farmers. The veterinarians generally perceived that they could treat animals with antibiotics when justified, and being restrictive with antibiotics was described as an expression of professional skill and not as challenging as animal welfare. Moreover, they stated that restrictive AMU seldom or never caused conflicts with farmers. Conclusion Strict AMU policy and restrictive AMU do not necessarily put veterinarians in a problematic position where they are caught between conflicting demands and risks

”The Swedish experience” – a summary on the Swedish efforts towards a low and prudent use of antibiotics in animal production

In 1986, Sweden, as the first country in the world banned all use of antibiotics as growth promoters in food animal production. Today Sweden has the third lowest sales of veterinary antimicrobial agents for food producing animals in Europe. In 2018, total sales of antibiotics for animal use in Sweden were 10 042 kg active substance as compared to 53.4 tonnes in 1984 (before the ban). The low use of antibiotics in animals and the comparatively favorable situation in Sweden with regards to antibiotic resistance are the results of decades of inter-sectorial collaboration and work on disease prevention and animal health. This review is a quick summary of the Swedish work towards a low and prudent use of antibiotics, including figures on antibiotic use in Swedish production animals and a discussion about important success factors as well as lessons learned

Trust, agreements, and occasional breakdowns: Veterinarians' perspectives on farmer-veterinarian relationships and use of antimicrobials for Swedish dairy cattle

Studies have shown that farmer-veterinarian relationships influence antimicrobial use (AMU) in livestock, though how they do so is unclear. On the one hand, research shows that well-established veterinarian-farmer relationships are positive for implementation of antibiotic stewardship and restrictive AMU. On the other hand, studies also show that farmer demands can increase antimicrobial prescribing and that prescribing antimicrobials can strengthen the veterinarian's relationship with farmer clients. In the present study, we focus on veterinarians' perspectives on the relationships between dairy cattle farmers and veterinarians in Sweden and explore what characterizes these relationships when restrictive AMU is described as unproblematic and when AMU becomes a matter of tension or conflict. The study draws on semistructured interviews with 21 veterinarians working with livestock in Sweden. Interviews were analyzed thematically. The study shows that from the perspectives of veterinarians, well-established veterinarian-farmer relationships generally facilitate restrictive AMU in 3 slightly different but related ways: (1) they create trust in the veterinarian and their prescribing decisions; (2) they create shared understanding concerning when antimicrobials are needed and not needed; and (3) they facilitate constructive discussions between veterinarians and farmers on AMU. To make the farmer feel listened to and to come to an agreement on AMU was described as central for the veterinarians. However, the veterinarians described agreements on restrictive AMU as sometimes requiring strategic work, such as discussions to motivate the farmer and leave the door open for antimicrobials later if needed. Such work takes time and energy and is easier within well-established relationships according to the veterinarians. We also identified examples where veterinarians explained that they occasionally make compromises with farmers concerning antimicrobials—compromises that, according to the veterinarians, facilitate the relationship with the farmer, which in turn facilities restrictive AMU in the longer term. The examples in our interviews where antimicrobials became a matter of tension and even conflict between veterinarians and farmers could, with a few exceptions, be traced to absence of well-established relationships. However, some veterinarians also described AMU as a matter of tension within well-established relationships, especially with older farmers who do not trust new treatment strategies. We also found a small number of examples where disagreements on antimicrobials made a relationship with specific farmers impossible. Thus, even though the interviewed veterinarians generally meant that their restrictive antimicrobial prescribing did not threaten the relationship with the farmer, our study also, to some extent, confirms research showing that restrictive AMU can harm the relationship with some clients who simply choose another, less restrictive, veterinarian. In summary, our study supports that decisions on AMU cannot be reduced to the individual prescriber's behavior, nor to a strict medical judgment. Antimicrobial use for dairy cattle needs to be understood as taking form in relationships in which both veterinarians and farmers are active parts