Diagnostic challenge in veterinary pathology: Generalized alopecia in a Holstein dairy cow

This study evaluated the effects of pedigree and genomic inbreeding on survival in Danish Jersey (JER) and Danish Holstein (HOL) dairy cows. Survival probabilities and hazard risks (HR) were estimated using Kaplan-Meier analysis and Cox proportional hazards models, with genomic inbreeding quantified through varying lengths of runs of homozygosity (ROH). The results indicated that JER cows had survival probabilities 1.3 to 4 percentage points higher after first calving and throughout later life, along with HR 22 to 29 percentage points lower compared with HOL cows. Both genomic (Froh) and pedigree inbreeding coefficients increased HR by 1% for each 1% increase in inbreeding. Differences in Froh based on ROH lengths revealed that longer segments (>10 Mb) increased HR by 2 to 3 percentage points, whereas shorter segments (1-2 Mb) reduced HR by 5 to 7 percentage points. Survival probabilities increased with increasing breeding values. These findings underscore the importance of managing genomic inbreeding to reduce overall culling risks and increase cow survival. Avoiding close inbreeding (ROH >5 Mb) and incorporating genomic relationships into breeding programs can promote the sustainability of dairy systems.

Simple SummaryBlood has been widely collected and analyzed for diagnosing and monitoring diseases in human beings and animals. A range of plasma proteins and peptides were set as biomarkers for pathological and physiological status. Previous researchers have explored how humans, pigs, dogs, and horses adapt to hypoxia at high altitudes. Additionally, the mechanism of hypoxia adaptation in human, mice, and shrimp was studied by proteomics. However, information on the adaptation mechanism of Holstein cows introduced to high altitudes is limited. The present study was conducted to the adaptation mechanism of Holstein dairy cows to high-altitude hypoxia by miRNA microarray analysis and the isobaric tags for relative and absolute quantitation (iTRAQ) iTRAQ technology. Based on the obtained results, Holstein dairy cows transported to Nyingchi may adapt to the high-altitude hypoxia through regulation of inflammatory homeostasis by up-regulating the acute phase response (APR) APR and activation of the liver X receptor/retinoid X receptor (LXR/RXR)LXR/RXR and farnesoid X receptor/ retinoid X receptor (FXR/RXR) FXR/RXR pathways.Changes in the environment such as high-altitude hypoxia (HAH) high-altitude hypoxia can lead to adaptive changes in the blood system of mammals. However, there is limited information about the adaptation of Holstein dairy cows introduced to high-altitude areas. This study used 12 multiparous Holstein dairy cows (600 ± 55 kg, average three years old) exposed to HAH conditions in Nyingchi of Tibet (altitude 3000 m) and HAH-free conditions in Shenyang (altitude 50 m). The miRNA microarray analysis and iTRAQ proteomics approach (accepted as more suitable for accurate and comprehensive prediction of miRNA targets) were applied to explore the differences in the plasma proteomic and miRNA profiles in Holstein dairy cows. A total of 70 differential miRNAs (54 up-regulated, Fold change (FC) FC > 2, and 16 down-regulated, FC < 0.5) and 226 differential proteins (132 up-regulated, FC > 1.2, and 94 down-regulated, FC < 0.8) were found in the HAH-stressed group compared with the HAH-free group. Integrative analysis of proteomic and miRNA profiles demonstrated the biological processes associated with differential proteins were the immune response, complement activation, protein activation, and lipid transport. The integrative analysis of canonical pathways were most prominently associated with the APR signaling (z = 1.604), and LXR/RXR activation (z = 0.365), and FXR/RXR activation (z = 0.446) pathways. The current results indicated that Holstein dairy cows exposed to HAH could adapt to high-altitude hypoxia by up-regulating the APR, activating the LXR/RXR and FXE/RXR pathways.

The objective of this study was to explore single nucleotide polymorphisms (SNPs), gene expression and economic evaluation of parameters associated with mastitis susceptibility in Holstein and Brown Swiss dairy cows. Two hundred and forty Holstein and Brown Swiss dairy cows (120 cows of each breed) were used in this study. The investigated dairy cows in each breed were allocated into two equal-sized groups (60 cows each); mastitis tolerant and affected groups. PCR-DNA sequencing of SELL, ABCG2, SLC11A1, FEZL, SOD1, CAT, GPX1, and AhpC/TSA revealed nucleotide sequence variations in the form of SNPs associated with mastitis tolerance/susceptibility in investigated Holstein and Brown Swiss dairy cows. Levels of SELL, SLC11A1 and FEZL gene expression were significantly up-regulated in mastitic Holstein and Brown Swiss dairy cows than in tolerant ones. Meanwhile, ABCG2, SOD1, CAT, GPX1, and AhpC/TSA genes were significantly downregulated. Regarding the economic parameters, significant differences were recorded for net returns and a reduction in the percentage of net profit, as the higher values of net returns were recorded for tolerant dairy cows than mastitic ones in both breeds; moreover, the net profit was reduced by 39% and 27% in mastitic Holstein and Brown Swiss dairy cows, respectively, when compared to tolerant ones. The results herein confirmed the potential significance of investigated genes as candidates for mastitis tolerance/susceptibility in Holstein and Brown Swiss dairy cows. Mastitis also has detrimental impacts on economic efficiency in dairy farms.

A diverse of recommendation has been made for the structure and management of dairy cows, despite demanding research, the relationship between lactation number and various factors is yet to be established. The present study was aimed to investigate the covariance among lactation number, growth performance, calving interval, and milk production was considered to increase an efficiency of selection schemes and to manage more efficiently Holstein dairy cows that have been raised on small-scale family farms in Republic of Korea. For that purpose, the data were observed from 850 Holstein dairy cows, which a total of 3929 milking, since April 2016 - January 2017. We measured the body weight, height, age, calving interval, and milk production of the each dairy cow. Also, information about the date of lactation, calving interval, and milk production was recorded using an automatic milking system(AMS) with identification numbers. Milk production was calculated per udder quarter in the AMS. Our study results showed the increased average body weight(p>0.05) in 1, 2, 3, and 4th lactating dairy cows and afterwards, we noticed the tendency on the average body weight(p<0.05) per lactation progressed. There was no significant difference noticed on height measurement of dairy cows. From the processing data of 850 Holstein dairy cows, the lactation number 1 and 7 had a greater calving interval with significantly lowered milk production, and the lactation number 2, 3, 4, 5, and 6 had significantly lowered the calving interval(p<0.05) with a greater milk production. From our study results, we evidenced that there is a significant relationship between the lactation number, growth performance, calving interval, and milk yield, and the maximum production of milk occurring in the 3rd and 4th lactation dairy cows. The achieved results from this study can be used by the small-scale farmers to encourage the structure and management of growth performance, calving interval, and milk yield in Holstein dairy cows in Korea.

BackgroundRuminants and monogastric animals exhibit significant differences in gluconeogenic efficiency. In dairy cows, hepatic gluconeogenesis serves as the primary source of glucose. Metabolites modulate gluconeogenesis efficiency through allosteric regulation, redox state, and signal transduction pathways. However, the liver-enriched metabolites that regulate hepatic gluconeogenesis in dairy cows and their specific regulatory mechanisms remain incompletely characterized.ResultsSix Holstein dairy cows and six Duroc × (Landrace × Yorkshire) (DLY) crossbred pigs served as research subjects. Employing non-targeted and targeted metabolomics, we discovered that three bile acids—taurodeoxycholic acid (TDCA), taurocholic acid (TCA), and glycocholic acid (GCA)—were highly enriched in Holstein dairy cows’ livers. In bovine hepatocytes, individual or combined stimulation of these bile acids significantly upregulated the expression of gluconeogenesis genes (FBP1, PCK1 and G6PC) and enhanced glucose production. In fasting mice with induced gluconeogenesis, TDCA, TCA, and GCA increased fasting blood glucose levels, and pyruvate tolerance tests further revealed their capacity to enhance hepatic gluconeogenesis, enabling more efficient glucose synthesis from pyruvate. Mechanistically, these bile acids activated Takeda G protein-coupled receptor 5 (TGR5), elevated intracellular cAMP levels, and ultimately enhanced gluconeogenesis via the transcription factor cAMP-response element binding protein (CREB). Notably, a TGR5 inhibitor abrogated the stimulatory effects of TDCA, TCA, and GCA on hepatic gluconeogenesis in fasting mice.ConclusionTDCA, TCA, and GCA are key metabolites promoting hepatic gluconeogenesis in dairy cows, with TGR5 as the pivotal receptor and the cAMP/PKA/CREB pathway as the critical downstream mechanism.Supplementary InformationThe online version contains supplementary material available at 10.1186/s40104-025-01275-w.

Simple SummaryPaper mulberry (Broussonetia papyrifera; PM) is a type of roughage rich in bioactive substances, such as phenolics and flavonoids, which are beneficial for animal health. This study evaluated the apparent digestibility of PM silage in Holstein dairy cows and its effect on the milk production, antioxidant capacity, and fecal bacteria composition of the animals. The results showed that the PM silage had no significant influence on the milk yield, apparent digestibility, and fecal bacteria composition of dairy cows. However, diets with PM silage can enhance the antioxidant and immune capacity of dairy cows, mainly due to the bioactive substance in PM. Today, faced with a shortage of feedstuff resources in ruminants, PM can be a useful feed resource for ruminants. Simultaneously, with the ban on antibiotics, PM may become an important functional feed for protecting animal health.Paper mulberry (Broussonetia papyrifera; PM) is an excellent and extensive type of roughage in Asia. This study aimed to evaluate the effects of PM silage on the milk production, apparent digestibility, antioxidant capacity, and fecal bacteria composition in Holstein dairy cows. Forty-five lactating Holstein dairy cows with a similar milk yield and parity were selected and randomly assigned to three groups. The control group was fed a non-PM silage diet, and the PM-treated groups were fed 4.5 and 9.0% PM silage supplementary diets for 28 days. Then, treatment groups were fed diets containing 13.5 and 18.0% PM silage for the next 28 days, respectively. PM silage increased the milk urea nitrogen and decreased the somatic cell count (p < 0.05), but did not affect the dry matter intake, milk yield, apparent digestibility, and energy balance of dairy cows. PM silage can enhance the blood total antioxidant capacity, superoxide dismutase, and immune globulin content (p < 0.05). The PM silage significantly decreased the relative abundance of the genera Ruminococcaceae UCG-013 and Tyzzerella-4 (p < 0.05). In conclusion, PM silage enhanced the antioxidant capacity and immunity of dairy cows, but did not influence the milk yield, dry matter digestibility, and fecal bacteria composition.

The objective of this study was to determine whether adding phytoncide oil (PO) and soybean oil (SBO) to the dairy cow diet could increase milk conjugated linoleic acid (CLA) and depress methane (CH4) emissions in Holstein dairy cows. Rumen fermentation was conducted at four levels of SBO (0, 1, 2, and 4%, on DM basis) and two levels of PO (0 and 0.1%, on DM basis) with in vitro experiment. To evaluate blood parameters, fecal microbe population, milk yield and fatty acid compositions, and CH4 production, in vivo experiment was conducted using 38 Holstein dairy cows divided into two groups of control (fed TMR) and treatment (fed TMR with 0.1% PO and 2% SBO as DM basis). In the in vitro study (Experiment 1), PO or SBO did not affect rumen pH. However, SBO tended to decrease ruminal ammonia-N (p = 0.099). Additionally, PO or SBO significantly decreased total gas production (p = 0.041 and p = 0.034, respectively). Both PO and SBO significantly decreased CH4 production (p < 0.05). In addition, PO significantly increased both CLA isomers (c9, t11 and t10, c12 CLA) (p < 0.001). Collectively, 0.1% PO and 2% SBO were selected resulting in most effectively improved CLA and decreased CH4 production. In the in vivo study (Experiment 2), 0.1% PO with 2% SBO (PSO) did not affect complete blood count. However, it decreased blood urea nitrogen and magnesium levels in blood (p = 0.021 and p = 0.01, respectively). PSO treatment decreased pathogenic microbes (p < 0.05). It increased milk yield (p = 0.017) but decreased percentage of milk fat (p = 0.013) and MUN level (p < 0.01). In addition, PSO treatment increased both the concentration of CLA and PUFA in milk fat (p < 0.01). Finally, it decreased CH4 emissions from dairy cows. These results provide compelling evidence that a diet supplemented with PSO can simultaneously increase CLA concentration and decrease CH4 production with no influence on the amount of milk fat (kg/day) in Holstein dairy cows.

Simple SummaryNatural and processed fat supplements directly affect milk yield and composition in cows. Oilseed extrusion is a heat-treatment process used for seeds fed to ruminants to prevent rumen biohydrogenation of unsaturated fatty acids. This process increases postruminal fat absorption when compared with the effects of feeding whole oilseeds. Hence, we investigated the effects of feeding a mixture of extruded linseed and soybean on lactation performance, first service conception rate, and mastitis incidence in Holstein dairy cows. We found that supplementing dairy cow feed with a mixture of extruded linseed and soybean at a rate of 100 g/kg feed increased milk yield and both monounsaturated and polyunsaturated fatty acid content. However, incidences of clinical mastitis and first-service conception rates were not affected by extruded linseed and soybean supplementation.This study quantifies the effects of extruded linseed and soybean (ELS) dietary supplementation on milk yield, composition, and fatty acid profiles, as well as first-service conception rate in Holstein dairy cows. Seventy-eight open Holstein dairy cows were divided into two groups: (1) a control, which received a basal diet; and (2) a test group, which received a basal diet supplemented with the ELS (650 g/kg of extruded linseed and 150 g/kg of extruded soybean) at a rate of 100 g/kg. In the ELS group, milk yield per day and solid not fat (SNF) yield increased by 3.26% and 0.88%, respectively, in relation to the control. Percentage milk fat decreased significantly by 1.4% in the ELS group when compared with the control. The ELS supplement resulted in a decrease in saturated fatty acids (SFAs) and an increase in monounsaturated (MUFAs) and polyunsaturated fatty acids (PUFAs) in milk. In conclusion, the supplementation of dairy cow feed with 100 g/kg of ELS increases milk yield and milk unsaturated fatty acids (especially MUFAs and PUFAs). ELS supplementation also causes a decrease in percentage fat and SFA levels but does not affect the first-service conception rate or the incidence rate of mastitis.

Veterinary pathology is a critical field in veterinary medicine, necessary for the diagnosis of diseases in animals. However, it is faced with numerous challenges that impact the accuracy and efficiency of diagnoses. This manuscript explores into the multifaceted issues within this field, and emphasised on diagnostic challenges. Key areas of concern include the complexity of differentiating between similar pathological conditions, the limitations of current diagnostic tools and techniques, and the variability in the manifestation of diseases across different species. Furthermore, the manuscript highlights the shortage of specialised pathologists, which exacerbates diagnostic delays and errors. Advanced diagnostic technologies, such as molecular pathology and digital imaging, are explored for their potential to enhance diagnostic precision, yet their high cost and limited accessibility present significant barriers. The integration of artificial intelligence and machine learning in veterinary diagnostics is also discussed as a promising avenue to overcome some of these obstacles. Case studies illustrating common diagnostic pitfalls and their consequences on animal health are provided, underscoring the need for continuous education and training in this rapidly evolving field. In conclusion, there is need for a concerted effort to standardise diagnostic procedures and improve collaboration among veterinary pathologists, clinicians, and researchers. By addressing these challenges, the veterinary pathology community can improve diagnostic accuracy, ultimately enhancing animal health outcomes.

Simple SummaryThree follow-up experiments as one set were conducted to evaluate the feed nutritional value of noni (Morinda citrifolia) meal to be included in the diet of Holstein dairy cows. An in vitro study was conducted to explore the effect of noni meal on rumen fermentation characteristics. An in situ study was conducted to evaluate the rumen degradation characteristics of noni meal, using wheat bran as a control. Finally, an in vivo study was carried out to investigate the applicability of noni meal as a feed ingredient for Holstein dairy cows. The in vitro study showed that the addition of noni meal up to 7% at 24 and 48 h of incubation did not negatively affect rumen fermentation characteristics. The in situ study showed that the rumen degradable protein content of the noni meal was high. The in vivo study showed that 1.5% noni meal can be used as a feed ingredient for Holstein dairy cows to improve the C18:1 fatty acid concentration in the milk.In three consecutive studies, we evaluated the effects of noni (Morinda citrifolia) meal on rumen fermentation and degradation characteristics, production performance, physiological parameters, and milk fatty acid profile in Holstein dairy cows. In in vitro (first study) and in situ (second study) experiments, rumen fluids from two fistulated Holstein dairy cows were used. The concentration of noni meal added was 0 (control), 1, 3, 5, or 7% of the basal diet (DM basis). In the in situ experiment, wheat bran was used as a control. Triplicated bags were incubated for 0, 4, 8, 12, 24, 48, 72, or 96 h. In an in vivo experiment (third study), 38 Holstein cows (145 ± 87 days DIM; 1.8 ± 0.9 parity; 35.4 ± 6.3 kg/day milk yield) were equally assigned to the control and treatment groups (19 cows each). Basal feed and noni meal pellets (1.5% of total feed DM basis) were fed to the treatment group. The control group was also fed the basal feed and pellets containing 0% noni meal. There were no significant differences in in vitro dry matter digestibility, pH, total gas production (TGP), CH4, NH3-N, and volatile fatty acids (p > 0.05). In the in situ experiments, the crude protein (CP) rapidly soluble fraction ‘a’ (CP-a) was higher in noni meal than in wheat bran, and rumen degradable protein was also higher in noni meal than in wheat bran. In the in vivo experiments, when noni meal pellets were fed, there was no significant difference in milk yield and composition, but the triglyceride levels decreased (p < 0.05), the C18:1 fatty acid level increased (p < 0.05), and the C18:0 fatty acid level decreased (p < 0.05). Collectively, noni meal can be used as a feed ingredient up to 1.5% (total feed DM basis) in Holstein dairy cows and as feed supplementation to increase the C18:1 fatty acid level in milk.

Endometritis is one of the reproductive diseases that can cause disturbances of postpartum uterine health in cattle. Therefore, identification of resistant genotypes to endometritis is essential. The objective of this study was to evaluate the association between the single nucleotide polymorphism in the interleukin-8 receptor-α (CXCR1) gene and the possibility of endometritis in Holstein dairy cows. For this purpose, blood samples were collected from multiparous dairy cows with a history of clinical endometritis (n = 30), and normal, healthy cows as the control group (n = 10). Deoxyribonucleic acid (DNA) was isolated from a blood sample. To determine genotype, the polymerase chain reaction-restriction fragment length polymorphism technique (PCR-RFLP) was used. The results indicated the presence of a different proportion of polymorphisms (G &gt; C) in the CXCR1 gene in cows with clinical endometritis, compared to the control group. Statistical analyses showed that there is a significant correlation between the incidence of the disease and the CXCR1 genotype in nucleotide position 956. The incidence rate of clinical endometritis was associated with the CXCR1.956 genotype; cows with genotype GC had a higher incidence of clinical endometritis compared with cows with the GG genotype. Overall, the results showed that CXCR1 polymorphism could be a useful marker for identification of resistant genotypes to endometritis in Holstein dairy cows.

Insulin-like growth factor-I (IGF-I) is one of the most important metabolic factors that plays a critical role in cow fertility. Recently, point mutation of IGF-I gene at nucleotide position 512 (C/T transition) within the 5′-untranslated region (5'-UTR) has attracted the most attention. It has previously been demonstrated that there was an important relationship between this type of mutation and IGF-I concentration in dairy cows serum. Hence, we investigate the relationship between polymorphism within 512 of the 5'-UTR of IGF-I gene and some reproductive parameters in Iranian Holstein dairy cows. Blood samples were collected from 60 multiparous cows with a history of desirable fertility (SPC<2; n=25) and undesirable fertility (SPC 2; n=35) based on the previous lactation numbers. The results showed that higher percentage (65%) of cows with CC genotype had desirable fertility (SPC<2); while a lower percentage of cows with TC (33.3%) and TT genotypes (14.3%) had good fertility (P<0.05). Therefore, the CC genotype was associated (P<0.05) with desirable fertility. In addition, the IGF-I mutation had a significant effect on service per conception and days open in which cows with TT genotype and TC genotype had greater average of services per conception and days open compared to cows with the CC genotypes (P<0.05). It can be concluded that the C/T mutation within this region of IGF-I gene may influence the reproductive parameters in Holstein dairy cows. These data support the hypothesis that the mutation in this site might be considered as a genetic marker for reproductive performance in Holstein dairy cows.

Odd- and branched-chain fatty acids in milk fat from Holstein dairy cows are influenced by physiological factors

Staphylococcal mastitis (SM) is a frequent disease in the dairy cattle that is costly to treat. This study aimed to investigate the alterations in the levels of procalcitonin (PCT), neopterin (NPT), haptoglobin (HP), serum amyloid A (SAA), proinflammatory cytokines (IL-1β, IL-8, TNF-α, IF-γ) and oxidative stress (OS) biomarkers in Holstein dairy cows with SM under field conditions. In addition, we also evaluated the role of examined biomarkers in disease pathogenesis and their use as diagnostic biomarkers for the disease in dairy cows. Fifty-three dairy cows with SM, including those with infections caused by Staphylococcus aureus (n = 42) and methicillin resistant S. aureus (MRSA) (n = 11) were selected for this study. In addition, 20 healthy dairy cows were enrolled as a control group. Higher serum levels of PCT, NP, IL-1β, IL-8, TNF-α, IF-γ, HP and SAA and a state of OS was detected in SM group in comparison with the controls. Moreover, the levels of all examined biomarkers in mastitic cows with S. aureus when compared with those infected with MRSA was not significantly different. All examined biomarkers demonstrated a significant degree of discrimination between SM cows and healthy controls (the area under the curve (AUC) ranged from 83.6 for SAA to 100 for PCT). Our study showed that SM in dairy cows was associated with substantial changes in serum PCT, NPT, Acute phase proteins (APPs), proinflammatory cytokines, and OS levels. This study demonstrates that clinical examination in tandem with quantification of PCT, NPT, APPs and cytokines, OS biomarkers could be a useful assessment tool for SM in dairy cows.

This study examined the colostrum nutritive composition, immunoglobulin (Ig), and microbial community in Holstein and Jersey dairy cows according to the time after calving. The experiment used seven Holstein and three Jersey dairy cows. Colostrum was collected immediately after calf calving, 12, and 24 hours, and stored at −80°C until analysis. An analysis of the nutritive composition in colostrum was performed using LactoScop. The immune indicators were analyzed using an ELISA Kit, and the microbial community was assessed using a Macrogen Inc. The protein level was high in all colostrum samples from Holstein dairy cows compared with Jersey dairy cows, but there was no significant difference according to the time after calving. Immune index analysis revealed high IgG and IgA concentrations in the colostrum of Holstein cows immediately after calving and 12 and 24 hours after calving, but the differences were not significant. The microbial community at the genus level revealed Staphylococcus to be predominant at a high rate in the colostrum of Holstein dairy cows and Enterococcus in Jersey dairy cows 12 hours after calving. Pseudomonas was predominant at a high rate in the colostrum of Jersey lactating cows immediately and 12 hours after calving. Chryseobacterium was predominant at a high rate in Holstein dairy cows 12 and 24 hours after calving. In conclusion, these results are expected to be used as research data on the correlation between quality, immunity, and microbial community in the colostrum. In the future, beneficial microorganisms in the colostrum of domestic dairy cows can be used to improve the growth and immunity of Holstein and Jersey calves and assist in research related to postbiotics industrialization.