Dairy, Volume 7, Issue 1 (February 2026) – 3 articles

Although best known as a major parasite of sheep and goats, the blood-feeding abomasal nematode Haemonchus contortus can also infect cattle and buffaloes under the mixed-grazing Mediterranean conditions prevalent in Greece. The objectives of this study were as follows: (i) to determine the prevalence of H. contortus infections in dairy and beef cattle and buffaloes in Greece through an abattoir survey, (ii) to evaluate potential host- and farm-related risk factors including age, sex, management system, cattle productive orientation, and the co-existence of cattle and buffaloes on the occurrence of haemonchosis, and (iii) to assess the likelihood of detecting homozygous benzimidazole (BZ)-resistant H. contortus in large ruminant populations in relation to these determinants. A total of 213 abomasa (115, 55, and 43 from dairy, beef cattle, and buffaloes, respectively) were examined. A structured questionnaire provided additional animal- and farm-level information. Haemonchus-like helminths were collected and molecularly identified at the species level by amplifying a 321 bp fragment of the internal transcribed spacer 2 region of nuclear DNA. An allele-specific multiplex PCR, targeting codon 200 of the β-tubulin gene, was applied to detect BZ-resistant alleles. The prevalence of H. contortus infection was 21.2% in cattle and 69.8% in buffaloes. In cattle, multivariable analysis revealed that mixed-species farming (i.e., farms where cattle were the primary species and buffaloes were kept in smaller numbers), productive orientation, and slaughter age were significant predictors of increased H. contortus infection. Controversially, none of these factors were significantly associated with infection in buffaloes. Finally, multivariable modelling suggested that resistance patterns varied by host species, being more prevalent in intensively managed, older cattle, yet less common among older buffaloes and in herds where both species coexisted. Full article

Hyperketonemia (HYK), defined by blood beta-hydroxybutyrate (BHB) ≥ 1.2 mmol/L, is described as a significant risk factor for cows developing postpartum (pp) diseases and impaired reproductive performance. The goal of the present study was to observe metabolic challenges in transition cows and to identify systemic markers reflecting HYK associated with lessened reproductivity. Fifty-four Simmental cows were monitored, revealing approximately 30% prevalence of HYK at the early pp period on 7, 14, or 28 days in milk (DIM). We assessed the dry matter intake, rumination time (RT), serum liver activity index, non-esterified fatty acids (NEFAs), acute phase proteins, and uterine and oviductal health. Elevated NEFA and reduced RT 14 days antepartum were a good predictor for HYK at 7 DIM. Hyperketonemia at 14 DIM resulted in higher milk yield compared with controls. We could neither detect differences in uterine health nor in reproductive key performance parameters between hyperketonemic and control cows, whereby the proportion of polymorphonuclear neutrophils in oviductal epithelia was significantly lower in hyperketonemic cows 14 DIM. We conclude that elevated concentrations of BHB in HYK 7, 14, or 28 DIM indicated energy supply to support physiological metabolic adaptations and lactation and that, in the absence of excessive inflammation during the transition period, HYK was not a risk factor for impaired fertility. Full article

We evaluated the effects of rapeseed oil (RSO, rich in oleic, linoleic, and linolenic acids) and a commercial fat source (BOVI-LM, rich in palmitic and stearic acids) on the growth performance and blood biochemical parameters of dairy calves during the pre- and post-weaning phases. Eighteen crossbred bull calves were randomly allocated in a randomized complete block design to three dietary treatments (Control, RSO, and BOVI-LM) during the milk-replacer phase (Phase 1, days 0–28). Due to technical issues, BOVI-LM supplementation was discontinued in Phase 2 (starter-feed phase, days 35–77), leaving only Control (n = 12) and RSO (n = 6). Energy supply was calculated to support target average daily gains of 0.6 (Phase 1) and 1.0 kg (Phase 2). Body weight, clinical health, and blood samples for biochemical analysis were monitored throughout the trial. No treatment effect on body weight or blood biochemical parameters was detected (main effect of treatment: p ≥ 0.18 for all analytes). In contrast, phase and time effects were significant for most biochemical parameters (p < 0.05), reflecting the metabolic transition from a milk-based to a solid-feed diet. Aspartate aminotransferase activity increased over time (p < 0.001), whereas glucose concentrations decreased post-weaning (time × phase: p = 0.020). The treatment × phase interaction was non-significant for all variables (p ≥ 0.13), supporting the absence of detectable carry-over effects and justifying the pooling of former BOVI-LM calves into the Control group in Phase 2. Full article