The effect of internal teat sealant products (Teatseal and Orbeseal) on intramammary infection, clinical mastitis, and somatic cell counts in lactating dairy cows: A meta-analysis

A systematic review and a series of meta-analyses were conducted to investigate the efficacy of selective dry cow antimicrobial treatment (SDCT) (in which only infected quarters/cows were treated with an antimicrobial) compared with blanket dry cow treatment (BDCT) (all quarters/all cows received an antimicrobial, regardless of their infection status). A full detailed protocol was published before initiating this review. Studies reporting on the (1) proportion of untreated quarters or cows when using SDCT, (2) intramammary infection (IMI) incidence risk over the dry period, (3) IMI elimination risk, (4) post-calving IMI prevalence, (5) early lactation clinical mastitis incidence, or (6) subsequent lactation milk yield and somatic cell counts were considered eligible. Thirteen articles representing 12 controlled trials, whether randomized or not, were available for analyses. SDCT reduced the use of antimicrobials at dry off by 66% (95% CI: 49–80). There was no difference in the elimination of existing IMI at dry off, between SDCT and BDCT. Meta-regression showed that the risk of IMI incidence during the dry period, IMI risk at calving, early lactation clinical mastitis risk, and early lactation milk yield and somatic cell counts did not differ between SDCT and BDCT as long as an internal teat sealant (65% bismuth subnitrate) was administered to untreated healthy quarters/cows at dry off. For trials not using internal teat sealants, SDCT resulted in higher risk than BDCT of acquiring a new IMI during the dry period and of harboring an IMI at calving. Lines of evidence strongly support that SDCT would reduce the use of antimicrobials at dry off, without any detrimental effect on udder health or milk production during the 1st months of the subsequent lactation, if, and only if, internal teat sealants are used for healthy, untreated quarters/cows.

Download Full-text

Evaluation of fully oxidized β-carotene as a feed ingredient to reduce bacterial infection and somatic cell counts in cows with subclinical mastitis

10.1101/2020.10.12.335463 ◽

2020 ◽

Cited By ~ 1

Author(s):

S McDougall

Keyword(s):

Treatment Group ◽

Somatic Cell ◽

Clinical Mastitis ◽

Control Group ◽

Cure Rate ◽

Bacteriological Cure ◽

Intramammary Infection ◽

Somatic Cell Counts ◽

Cell Counts ◽

Β Carotene

AbstractAimsTo assess the effect of oral supplementation with fully oxidised β-carotene (OxBC) on bacteriological cure, incidence of clinical mastitis, and somatic cell counts (SCC) in cows with subclinical intramammary infection.MethodsCows from four dairy herds were enrolled in early lactation if they had quarter-level SCC >200,000 cells/mL and they had a recognised bacterial intramammary pathogen in one or more quarters. They were randomly assigned to be individually fed from Day 0, for an average of 40 days, with 0.5 kg of a cereal-based supplementary feed that either contained 300 mg of OxBC (treatment; n=129 quarters) or did not (control; n=135 quarters). Quarter-milk samples were collected on Days 21 and 42 for microbiology and SCC assessment. Bacteriological cure was defined as having occurred when the bacteria present on Day 0 were not isolated from samples collected on Days 21 or 42. Clinical mastitis was diagnosed and recorded by herdowners up to Day 42.ResultsThe bacteriological cure rate was greater for quarters from cows in the treatment group (13.9 (95% CI=4.1–23.7)%) than for quarters from cows in the control group (6.9 (95% CI=4.8–9.1)%; p=0.02). The prevalence of quarters that were infected on Day 42 was less in cows in the treatment group (79.9 (95% CI=62.3-97.6)%) than the control group (88.2 (95% CI=78.4-97.9)%; p=0.009). The incidence of quarters diagnosed with clinical mastitis by Day 42 was lower in cows from the treatment group (1/129 (0.78 (95% CI=0.02-4.24)%) than in cows from the control group (6/135 (4.44 (95% CI=1.65-9.42)%; p=0.03). Mean quarter-level SCC did not differ between treatment groups (p=0.34).Conclusions and Clinical RelevanceFeeding 300 mg/cow/day of fully oxidised β-carotene resulted in a higher bacteriological cure rate, a lower prevalence of intramammary infection following 6 weeks of feeding, and a lower incidence of clinical mastitis compared to untreated controls. This offers a non-antimicrobial approach to reducing prevalence of intramammary infection in dairy cows.

Download Full-text