Bianca Cornelia Lungu

Heat stress, indexed by the Temperature–Humidity Index (THI), can alter milk composition; we aimed to quantify the association between daily THI and milk fat (%) and lactose (%) in Romanian Simmental and Romanian Brown cows using routine test-day records. We conducted a retrospective, repeated-measures study of 20,564 test-day observations from 1,123 cows (2014 to 2024), linking each control to same-day THI (observed range ≈28.5–78.7). Linear mixed-effects models with a random intercept for cow included a THI×month interaction and adjustments for breed, parity, and a smooth term for days-in-milk; effects are reported per +10 THI. Results showed season-dependent responses. For fat, higher THI was associated with decreases in mid-summer and late winter (e.g., January −0.12, February −1.09, July −0.21, August −0.75 per +10 THI), but with increases across much of spring and autumn (e.g., March +0.21, April +0.19, May +0.47, September +0.78, October +0.08, November +1.14, December +0.12). For lactose, associations were predominantly negative year-round, with small exceptions (e.g., March +0.03; April ~0): decreases were observed in January −0.047, February −0.171, May −0.111, June −0.135, July −0.064, August −0.097, September −0.121, October −0.050, November −0.048, and December −0.095 per +10 THI. A pooled comparison confirmed concurrent reductions in both fat and lactose during warm months (June–August), whereas outside summer, fat generally increased with THI while lactose remained mildly negative. In conclusion, rising THI is linked to a summer depression of milk fat and modest, broadly negative shifts in lactose; month-specific interactions highlight the importance of modeling seasonal context when evaluating milk-quality resilience in these breeds.

Thermal stress significantly affects the metabolic efficiency and health of cattle, with cellular bioenergetics and mitochondrial function being key targets. The regulation of oxidative metabolism and thermotolerance is largely governed by specific ge-netic markers that reflect adaptive responses to heat exposure. This review discusses genes involved in mitochondrial respi-ration and stress response mechanisms, such as those encoding components of the electron transport chain (ND1–ND5, COX1–COX3, CYCS), heat shock proteins (HSP70, HSP90), and antioxidant enzymes (SOD1, NRF2, PGC-1α). Alterations in the expression of these genes provide valuable insights into mitochondrial efficiency and cellular adaptation to elevated temper-atures, reflecting the dynamic processes that allow cattle to cope with heat stress. Furthermore, disruptions in these path-ways may contribute to metabolic inefficiencies, negatively impacting overall health and productivity. Additionally, this re-view explores the potential of integrating transcriptomic, proteomic, and genomic data to identify molecular markers associ-ated with heat tolerance. Such approaches provide valuable insights into the mechanisms underlying thermal resilience, which can guide genetic selection strategies aimed at improving cattle health and productivity in extreme temperature condi-tions.

Somatic cell count (SCC) and differential somatic cell count (DSCC) are widely recognized as reliable indicators of udder health and inflammation in dairy cows. Recent advances in statistical modeling and biochemical analysis have enabled more refined predictions of these indicators using milk composition traits. The objective of this study was to investigate the associations between key milk biochemical parameters (fat, protein, casein, lactose, solids non-fat, total dry matter, pH, urea, acetone, and β-hydroxybutyrate-BHB) and udder health indicators, and to identify the most robust predictive model for SCC. A total of 272 milk samples were collected from cows under the Official Performance Recording Milk Production program in Arad County, Romania, and analyzed using the CombiFoss™ FT+ system. After outlier removal, 251 samples were retained for analysis. Data preprocessing included standardization and log-transformation of SCC to improve model assumptions. Statistical modeling involved stepwise regression with interaction terms, as well as Ridge and Lasso regularization techniques. The best results were obtained using the Lasso model for log (SCC), which achieved the highest predictive accuracy (R² = 0.655), selecting biologically relevant predictors such as protein, BHB, casein, lactose, and DSCC. The model's predictions aligned closely with measured values and confirmed known correlations, such as the negative association between lactose and SCC and the positive association of BHB and protein with SCC. Although the Lasso model for DSCC showed lower predictive power (R² = 0.175), it selected key predictors (protein, acetone, and BHB) similar to other models, underlining the complex physiological basis of DSCC. Ridge regression confirmed these trends, supporting the robustness of the selected variables. These findings emphasize the utility of regularized regression, particularly Lasso, in developing practical tools for early mastitis screening based on routinely collected milk composition data, with potential applications in herd health monitoring and decision-making on commercial dairy farms.

Milk urea nitrogen (MUN) is a critical biomarker for nitrogen efficiency in dairy systems, yet limited data exists for Eastern European dual-purpose breeds. This study evaluated MUN variation patterns in Romanian Brown and Romanian Simmental cattle to optimize nitrogen management and support EU environmental goals. We analyzed 4,311 test-day records from 544 cows (102 Romanian Brown, 442 Romanian Simmental) collected between 2020-2025 in year-round housed free-stall systems. Linear mixed models with REML estimation assessed effects of breed, season, lactation stage, parity, and their interactions on MUN concentration. Mean MUN was 10.93±5.50 mg/dl with significant seasonal variation (p 0.001), showing spring peaks (12.91 mg/dl) and winter lows (8.62 mg/dl) despite continuous indoor housing. A significant breed × season interaction (p 0.001) revealed differential responses: Romanian Brown exhibited greater seasonal amplitude (5.16 mg/dl range) versus Romanian Simmental (3.51 mg/dl). The model explained 33.9% of total variance with moderate repeatability (ICC=0.1145). Dual-purpose Romanian cattle show pronounced seasonal MUN patterns with breed-specific responses, indicating opportunities for targeted nutritional management and genetic selection to improve nitrogen efficiency while meeting environmental regulations.

Bovine mastitis is a prevalent and costly disease that has a significant impact on the welfare of dairy cows. The produc-tion losses resulting from clinical mastitis (CM) and subclinical mastitis (SCM) can be evaluated using somatic cell count (SCC). One commonly used parameter derived from SCC is the Linear Score (LS), which is a logarithmic conversion of SCC based on base 2. This study aims to explore whether the Linear Score of somatic cell count correlates with other milk components and if it can serve as a reliable predictor of "healthy" and "infected" cows in milk analysis reports. The study emphasizes the significant cor-relations and impact of mastitis (quantified by the Linear Score) on milk composition, including increases in fat (t = -3.794, p = 0.000), protein (t = -5.227, p = 0.000), and casein (t = -4.483, p = 0.000), as well as decreases in lactose (t = 8.762, p = 0.000). However, the study does not support associations between LS and non-fat dry matter (t = -1.583, p = 0.115) or ketone bodies (t = -1.602, p = 0.111). Additionally, the Linear Score approach highlights the importance of using SCC as a diagnostic tool for de-tecting mastitis, monitoring milk quality, and assessing the efficiency of treatment protocols.

Heat stress poses a significant challenge to dairy cattle by disrupting physiological homeostasis, reducing productivity, and altering nutrient metabolism. A central adaptive mechanism to HS involves enhanced proteolysis and mobilization of skeletal muscle, supplying amino acids for energy production via gluconeogenesis. This review synthesizes current findings on the effects of HS on intracellular, circulating, and milk amino acid profiles in dairy cows, with an emphasis on identifying potential biomarkers of thermal stress. Multiple studies demonstrate that heat stress modulates amino acid metabolism across tissues, with notable compartment-specific changes. Intracellular concentrations of certain amino acids such as proline, glutamine, and valine often increase under heat stress, while their systemic and milk levels tend to decline, suggesting increased cellular retention and utilization. Essential AAs like lysine, methionine, and isoleucine consistently decrease in blood and milk, reflecting compromised availability and altered mammary uptake. Moreover, heat stress impacts amino acids involved in immune modulation (e.g., threonine), nitrogen metabolism (e.g., arginine, citrulline, ornithine), and neurotransmitter biosynthesis (e.g., Triptophan, Tyrosine), underscoring their regulatory roles in stress adaptation. The differential response of amino acids across biological compartments highlights the complexity of their metabolic regulation under heat stress. Milk and blood amino acid profiling emerges as a promising tool for monitoring thermal stress, with lysine, glutamine, and proline among the most responsive candidates. Overall, the evidence underscores the value of targeted AA analysis for understanding and potentially mitigating the metabolic impacts of heat stress in dairy cattle.

This study investigates the impact of caponization on the growth, development, and behavior of broiler roosters. The results demonstrate that caponization leads to a significant increase in weight compared to the control group, particularly noticeable after week 4. Additionally, caponized roosters exhibited larger, redder combs, indicating sexual maturity, and showed less aggressive behavior. In contrast, the control group experienced slower growth, likely due to the influence of natural hormones. These findings suggest that caponization not only enhances growth but also positively influences the behavior and overall welfare of roosters, making it a promising approach for poultry management.

The evaluation of external pelvimetry measurements and the genetic factors influencing them is essential for improving morphological characteristics and reproductive performance in cattle. This study represents the first comprehensive analysis of the association between single nucleotide polymorphisms (SNPs) and external pelvimetry traits in Romanian Simmental cattle, a breed recognized for its distinctive pelvic morphology. The relationship between single-nucleotide polymorphisms (SNPs) and external pelvimetry traits—including croup height (CH), buttock height (BH), croup width (CW), rump angle (RA), and croup length (CL)—was examined in Simmental cows. From an initial set of 110 SNPs, 33 markers were retained after applying quality control filters, including a minor allele frequency (MAF) greater than 0.05 and Hardy–Weinberg equilibrium. These SNPs, located on multiple chromosomes, were identified within intronic, exonic, or regulatory regions of relevant genes such as CLSTN2, DPYD, FBXL7, FBXL13, SEMA6A, RUNX2, FSTL4, DST, DCBLD2, FRMD6, CAV2.3, ABL2, SH3BP4, RSBN1L,and SAMD12, suggesting that these genetic variants may influence the development and morphology of the pelvic bones. Statistical analysis revealed significant relationships between certain allele variants and croup measurements, highlighting that the presence of alternative alleles can modify their morphological traits. Notably, the G allele in CLSTN2 reduced croup height by 5.74 cm (p = 0.0227), while the T allele in RUNX2 decreased rump angle by 4.49° (p = 0.0119).

Eye disease in dogs is a common problem that can affect both the health and well-being of the animals. The aim of the study was to investigate the prevalence and incidence of the most common eye diseases in a large population of dogs from two stray dog centers in northwestern Romania over a two-year period.We conducted a retrospective observational study of 208 eye diseases in two dog shelters in northwestern Romania: the “Ham Ham” Association and the “Free Life” Association in Satu Mare County. The study spanned from January 2022 to December 2023. We collected data on eye disease status from a total of 2293 dogs. The dogs were categorized into three age groups: young dogs (under 2 years), adult dogs (2 to 7 years), and senior dogs (over 7 years). Additionally, the dogs were grouped by sterilization status and gender. The statistical analysis was performed using Pearson’s chi-squared test, Student’s t-test, and binary logistic regression. The prevalence of ocular diseases in this study was 9.07%, with 208 out of 2293 dogs diagnosed with eye problems. The most common ocular diseases observed were conjunctivitis (58/208 or 27.9%), eyelid issues (50/208 or 24%), cataracts (40/208 or 19.2%), glaucoma (13/208 or 6.3%), keratopathies (10/208 or 4.8%), traumatic eye injuries (10/208 or 4.8%), foreign bodies (7/208 or 3.4%), blepharitis (5/208 or 2.4%), proptosis (3/208 or 1.4%), progressive retinal atrophy ((3/208 or 1.4%), retinal detachment ((3/208 or 1.4%), and dry eye (2/208 or 1%). Among the three age groups, puppies and young dogs (under 2 years) were the most affected, with a punctual prevalence of 50.96% at the “Free Life” center and 65.51% at the “Ham Ham” center. Compared with older dogs, the younger dogs were 4.91 times more likely to develop conjunctivitis (OR = 4.91, p = 0.001), 9.38 times more likely to develop eyelid problems (OR = 9.38, p < 0.000), and 0.31 times less likely to develop cataracts (OR = 0.31, p = 0.019).Our epidemiological study found that eye diseases are common among shelter dogs, with incidence rates (new cases over a specific period) varying by age. The youngest and oldest dogs were the most affected, with the highest prevalence observed in the youngest group. The study also highlighted the significant impact of factors such as the shelter center (p < 0.000), age (p < 0.000), and sterilization status (p < 0.000) on the prevalence of eye disorders. These findings underscore the need for enhanced awareness about eye diseases and their risk factors to facilitate early diagnosis and treatment.

Staphylococcus aureus is recognized worldwide as one of the major agents of dairy cow intra-mammary infections and cause a wide variety of clinical diseases in humans. Staphylococcus aureus can be transferred during milking from milkers (especially from their hands that come into contact with the udder) to cows. The exchange of resistance genes is very effective during colonization or infection of host organisms. The aim of this study was to determine the prevalence of Staphylococcus aureus isolated from the nasal cavities of milkers. In this study were taken 30 samples from nostrils of milkers and 66.6% of them were confirmed as Staphylococcus aureus. For these isolates, 25 antibiotics were tested using the PBC29 panel and all isolates (100%) were found to be resistant to ampicillin and penicillin. Through the qPCR reaction, 6 resistance genes (blaZ, cfr, ermB, ermC, mecA, and tetK) were tested and 13 antibiotics were associated with them. For each gene it was calculated the penetrance (P%) and diagnostic odds ratio (DOR) to see if the phenotypic expression of resistance/susceptibility is also found in genes. In this study, overall penetrance was P%=52%, the penetrance had values between 22% (tetK) and 80% (blaZ) and DOR had superunitary values in mecA gene (DOR=1.21), cfr (DOR=1.53), ermB (DOR=2.54) and ermC (DOR= 5.44).This approach can enhance the understanding of plasmid-borne resistance and improve diagnostic accuracy, ultimately contributing to better management of antimicrobial resistance in veterinary settings.