Accurate identification of mastitis-causing bacteria supports effective management and can be used to implement selective use of antimicrobials for treatment. The objectives of this study were to compare the results from a culture-based mastitis pathogen detection test kit ('VetoRapid', Vétoquinol) with standard laboratory culture and to evaluate the potential suitability of the test kit to inform a selective treatment programme. Overall 231 quarter milk samples from five UK dairy farms were collected. The sensitivity and specificity of the test kit for the identification of Escherichia coli, Staphylococcus aureus, coagulase-negative staphylococci, Streptococcus uberis and Enterococcus spp. ranged from 17 per cent to 84 per cent and 92 per cent to 98 per cent, respectively. In total, 23 of 68 clinical samples were assigned as meeting the requirement for antimicrobial treatment (Gram-positive organism cultured) according to standard culture results, with the test kit results having sensitivity and specificity of 91 per cent and 78 per cent, respectively. Several occurrences of misidentification are reported, including S. aureus being misidentified as coagulase-negative staphylococci and vice versa. The test kit provides rapid preliminary identification of five common causes of bovine mastitis under UK field conditions and is likely to be suitable for informing selective treatment of clinical mastitis caused by Gram-positive organisms.

No abstract

Mastitis, inflammation of the mammary gland, is often caused by intramammary infection with bacterial organisms. It impacts on dairy cattle welfare, production, udder health and longevity in the herd. Current detection methods for mammary inflammation and infection all have limitations, particularly for on-farm diagnosis of non-clinical mastitis after calving. Acute phase proteins have been suggested as alternative early indicators of the disease and can potentially be used as cow-side test with results in real time. In this study, milk haptoglobin concentrations were investigated over the first week postpartum to explore haptoglobin's potential as indicator of udder health in dairy heifers. Haptoglobin concentration was highest on day 3 of lactation, and was positively correlated with somatic cell count, a commonly used marker of inflammation (r=0.68). Haptoglobin level was also associated with bacteriological culture results, a key indicator of infection status, whereby median haptoglobin concentration on days 3 and 5 was higher in quarters that were infected at calving than quarters that were non infected at calving. Sensitivity and specificity of haptoglobin concentration as indicator of infection were low, both for lenient and strict culture-based definitions of intramammary infection (57 or 60% and 61 or 63%, respectively). Although haptoglobin was a poor biomarker for intramammary infection with coagulase negative staphylococci in heifers during the first week after calving, it may have value as an indicator of major pathogen infections, particularly in large scale dairy herds where pre-partum heifers are managed off-site.

The objective of this study was to identify the prognostic value for survival of blood parameters in the immediate post-caesarean surgery period in kids born from pregnancy toxaemia (PT) goats. This study involved 10 PT goats, in which a caesarean surgery was performed. Twenty-five kids were born after caesarean surgery of which 16 survived. A blood sample was collected from the jugular vein of the 10 goats and from the kids immediately after caesarean surgery (within 15 min). There were differences between the kids that survived and the kids that did not survive concerning the blood levels of pH (7.22 vs 7.00), base excess (− 9 vs − 18 mmol/L), pCO2 (46 vs 62 mmHg) and L-lactate (5.6 vs 16 mmol/L). Maternal ketoacidosis due to PT has a negative impact on the survival rate of the offspring. This appears to be associated to a metabolic acidosis of the offspring. However, the only blood parameter in which there was a strong association between the maternal and newborn kids was blood urea nitrogen (r = 0.97).

High-yielding dairy cows experience a negative energy balance and inflammatory status during the transition period. Fat supplementation increases diet energy density, and plasma n-3 polyunsaturated fatty acids (PUFA) have been proposed to improve immune function. This study tested the hypothesis that dietary supplementation with a rumen-protected and n-3 PUFA-enriched fat could ameliorate both the energetic deficit and immune status of postpartum high-yielding dairy cows, improving overall health and reproductive efficiency. At 11 d in milk (DIM), cows were randomly allocated to groups (1) n-3 PUFA (n = 29), supplemented with encapsulated linseed oil supplying additional up to 64 g/d (mean 25 ± 4 g/d) of α-linolenic acid (ALA), or (2) control (n = 31), supplemented with hydrogenated palm oil without ALA content. Fat supplements of the n-3 PUFA and control groups were available through an automated, off-parlor feeding system, and intake depended on the cow's feeding behavior. Plasma ALA concentrations were higher in n-3 PUFA than control cows, following a linear relation with supplement ingestion, resulting in a lower n-6/n-3 ratio in plasma. Metabolic parameters (body condition score and glucose and β-hydroxybutyric acid blood concentrations) were unaffected, but milk yield improved with increased intake of fat supplements. Plasma total adiponectin concentrations were negatively correlated with ingestion of n-3 PUFA-enriched fat supplement, following a linear relation with intake. Conception rate to first AI increased with higher intake of both fats, but a decrease of calving-to-conception interval occurred only in n-3 PUFA cows. Postpartum ovarian activity and endometrial inflammatory status at 45 DIM were unaffected. In conclusion, this study evinced a posi-tive linear relation between rumen-protected linseed fat intake and plasma n-3 PUFA concentrations, which modulated adiponectin expression and improved reproductive parameters.

No abstract

Heifer mastitis in early lactation impacts negatively on animal welfare, milk production and longevity. A major challenge for the prevention and control of mastitis in dairy heifers is to establish when intramammary infection occurs because pre-partum secretum sampling is risky. We evaluated a ventrodorsal projection to capture thermal images of the entire udder of primigravid and compared results against caudocranial projection, which is used in lactating cattle. Based on the analysis of 119 heifers and images taken at 2 months and 2 weeks pre-partum, a very strong positive correlation (r = 0.91 and r = 0.96, respectively) was shown between caudocranial and ventrodorsal projections of hind quarters. Quarter maximum gradient temperatures were consistently greater on ventrodorsal projection than on caudocranial projection, and less variable than minimum gradient temperatures. The collection of ventrodorsal images is a simple one-step method involving the imaging of the entire udder in a manner safe for both the cattle and handlers. Together, these results demonstrate that a single projection can be used to scan the entire udder of primigravid dairy heifers in commercial farm conditions, with the potential to implement this as a routine method for the early detection of intramammary infection based on udder surface temperature.

Oak toxicity in cattle results from ingestion of acorns, buds, leaves, sprouts, and saplings from several species of trees in the genus Quercus, all of which contain high concentrations of tannins. Consumption of acorns by ruminants, principally between late summer and early winter, is common in the south of Portugal, where there is a high prevalence of Quercus suber. Oak poisoning can lead to progressive damage to the kidneys and may result in renal failure and death. This study involved 17 beef cows that died of chronic oak poisoning related to ingestion of Quercus suber. The most relevant findings from necropsy examinations were abdominal fluid accumulation, atrophic/fibrotic kidneys, mesenteric and sub-mandibular edema, absence of body fat reserves and muscle atrophy, and weight loss. The most significant histopathologic finding was chronic interstitial nephritis. Elevated blood urea nitrogen, creatinine, and K+ values and reduced albumin values were found in 4 cows examined ante-mortem. Straight-bred Mertolengo cows appeared to be highly resistant to oak toxicity.