Levels of selected cytokines and acute–phase proteins in the serum of dairy cows with cystic ovarian disease and those in follicular and luteal phases of normal ovarian cycle

Cystic ovary disease (COD) alters structure and function of the bovine oviduct

Cystic ovary disease (COD) is a common cause of subfertility in dairy cattle. Therefore, the aim of this study was to provide novel concepts for cyst classification and to investigate the effects of COD on tubal microarchitecture, oviductal metabolic function, and the formation of the sperm reservoir. Bovine Fallopian tubes affected by follicular cysts, follicular cysts with luteinization and luteal cysts were investigated by a variety of microscopic and histological techniques and compared to control cows in metestrus and diestrus. We defined three types of cysts involved in COD, each of which had a characteristic wall thickness, inner wall appearance and cellular pattern within the cyst aspirate. Regarding the Fallopian tube, each cyst type was associated with a characteristic morphology, specifically the microarchitecture of the folds in ampulla, epithelial cell ratios, and ciliated/secretory cell size and form. Furthermore, each cyst type showed different patterns of tubal glycoprotein and acidic mucopolysaccharide synthesis, which was highly variable as compared to the controls. Our studies are the first to characterize the effects of COD on the Fallopian tube, which promotes the establishment of novel, cyst-specific therapeutic concepts in cattle and helps gain a holistic view of the causes of subfertility in cows with COD.

A simple, inexpensive and portable on-farm test for pregnancy diagnosis and ovary status in cows via chemical analysis of urine

Ovary dysfunction causes an aberrant endocrine surge at various reproductive cycle stages, negatively impacting fertility and economic profit. Optimizing dairy cow performance requires determining ovarian status and detecting early pregnancy. Still, little to no information is available about the diagnosis of the ovarian condition using urine chemical analysis at the field level in Bangladesh. This study aimed to develop a simple, inexpensive and portable on-farm technique for pregnancy diagnosis and ovary status determination in cows via chemical urine analysis. Fifty reproductively healthy cows were recruited from different donor farms. Prior to artificial insemination (AI), all selected cows were placed in a single ovsynch program. TAI (timed artificial insemination) was carried out. Urine was routinely collected from Day 0-55 days at estrus cycle stages for routine chemical analysis using barium chloride (BaCl2), followed by commercially available protein strip tests. The developed techniques for pregnancy and ovary status diagnosis in cows were validated with rectal palpation (RP). Barium chloride (BaCl2) analysis of urine revealed white precipitation corresponding to a mature follicle in the ovary during estrus and colorless precipitation corresponding to the corpus luteum during the diestrus period. Positive pregnancy was indicated by the presence of a colorless precipitate in the BaCl2 test, and a protein value of less than 100 mg/dl was found in the protein strip test. The maximum accuracy (42/50, 84%) was observed between 25 and 35 days, as confirmed by RP. Perplexing results were seen 45-55 days after AI, between pregnancies and luteal cystic disease. In both cases, we discovered that the BaCl2 precipitation was colorless. However, the protein value in the context of luteal cystic disease was found to be higher than 100 mg/dl. The barium chloride test, followed by protein strip tests, is a simple and portable way to diagnose pregnancy and determine ovarian status in cows at the field level.

Assessment of selected immunological parameters in dairy cows with naturally occurring mycotoxicosis before and after the application of a mycotoxin deactivator

Introduction

Mycotoxins in dairy cows can cause many non-specific symptoms often resulting from immune system overreaction. The study assessed the concentration of selected cytokines and acute phase proteins (APP) in cows with natural mycotoxicosis before and after using a mycotoxin neutraliser. The cytokines were tumour necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and interleukin 10 (IL-10), and the APP were serum amyloid A (SAA) and haptoglobin (Hp).

Material and Methods

The research was carried out on an experimental group (Exp) of 10 herdmate Holstein-Friesian cows with mycotoxicosis. The control group (Con) was 10 healthy cows of the same breed from a different herd. Cows in the Exp group were administered the mycotoxin deactivator Mycofix for three months. Blood was drawn from Exp cows once before administering Mycofix and a second time after three months of its use. Blood was also drawn from Con cows at the same times. Serum levels of TNF-α, IL-6, IL-10, SAA and Hp were assessed using ELISA.

Results

The concentrations of all cytokines and Hp in Exp cows were higher before treatment (P < 0.001) than those in Con cows. After three months of administering Mycofix, the concentrations of TNF-α and IL-6 were significantly lower than their pre-treatment levels (P < 0.001). The concentrations of IL-6, IL-10, and Hp were still significantly higher than those in the Con group (P < 0.001). In cows with mycotoxicosis, simultaneous stimulation of antagonistic processes was noted: a pro-inflammatory process in the upregulation of TNF-α and IL-6, and an anti-inflammatory one in the upregulation of IL-10.

Conclusion

Despite the absorbent’s use and the resolution of clinical symptoms in Exp cows, high levels of IL-10 and Hp and IL-6 were maintained. Assessment of the level of cytokines and APP appears to be a useful and precise tool for the evaluation and application of the appropriate dose of the mycotoxin absorbent or the evaluation of its effectiveness.

Cystic ovary disease impairs transport speed, smooth muscle contraction, and epithelial ion transport in the bovine oviduct

Cystic ovary disease (COD) is a common cause of bovine infertility but the impact of this disease on the oviduct is unknown. The aim of this study was to analyze the effects of COD on particle transport speed (PTS), ciliary beat frequency, myosalpinx contraction, and epithelial ion transport. Oviducts were obtained from cows affected by COD and compared with those of healthy, mid-diestrus cows. PTS and CBF were examined using live-cell imaging. Smooth muscle contraction and epithelial ion transport were investigated using organ baths and Ussing chambers. Our results showed that muscarinic receptors are involved in cholinergic signaling in the oviduct and that forskolin-induced cyclic AMP production is involved in active ion transport in the oviductal epithelium. Oviducts from cows with luteal cysts revealed significantly decreased PTS (p = 0.02). Further to that, in the oviducts of COD cows, the cholinergic regulation of smooth muscle contractions and active epithelial ion transport were significantly diminished (p < 0.0001). These results imply that in COD cows, oviductal transport is compromised by decreased fluid flow speed and reduced cholinergic regulation of smooth muscle contraction and ion transport. This knowledge contributes to a more comprehensive understanding of COD supporting the development of novel therapeutic concepts for infertility treatment.

Comparative evaluation of cytokine and acute-phase protein concentrations in sera of dairy cows with subclinical and clinical ketosis as a different view of the causes of the disease

Background and Aim:

Ketosis is a common disease occurring during the first stage of lactation in highly productive dairy cows. The aim of the present study was the comparative assessment of selected pro-inflammatory cytokines (including tumor necrosis factor-α [TNF-α] and interleukin 6 [IL-6]), anti-inflammatory cytokines (including IL-10), and acute-phase proteins (APPs) (including haptoglobin [Hp] and serum amyloid A [SAA]), in the sera of cows with subclinical ketosis (SCK), in those with clinical ketosis (CK), and in healthy cows.

Materials and Methods:

Thirty dairy cows of Holstein-Friesian breed were investigated. The cows were divided into three groups depending on the serum β-hydroxybutyric acid (βHBA) level. The control, SCK, and CK groups included healthy cows, cows with SCK, and cows with CK, respectively. BHBA concentration in blood serum was determined using colorimetric method. The blood serum was used for proper tests. Cytokine (TNF-α, IL-6, and IL-10) and APPs (SAA and Hp) concentrations in the investigated samples were determined by enzyme-linked immunosorbent assay method.

Results:

The SCK group had significantly higher TNF-α, IL-6; IL-10, and SAA values than had the CK group (p<0.01). The SCK group had a lower Hp concentration than had the CK group (p<0.05).

Conclusion:

This study showed that the inflammation intensity is higher in the initial phase of the disease and decreases during the advancement, probably due to active anti-inflammatory mechanisms (an increase of IL-10 concentration), which protect animal organism from self-destruction. On the basis of our study, it can be assumed that ketosis development in dairy cows was preceded by the systemic inflammation that may influence the progress of this disease.

Mitochondrial membrane protein mitofusin 2 as a potential therapeutic target for treating free fatty acid-induced hepatic inflammation in dairy cows during early lactation

Inflammation is critical in the progression from benign hepatic lipidosis to pathological hepatic steatosis. The objective of this study was to examine the potential role of the outer mitochondrial membrane protein mitofusin 2 (MFN2) in the etiology of hepatic steatosis in dairy cows during early lactation. Using a nested case-control design, we compared blood and liver samples from 10 healthy cows and 10 age-matched cows with moderate fatty liver. Cows with moderate fatty liver had high liver triacylglycerols, elevated plasma concentrations of free fatty acids (FFA) and β-hydroxybutyrate, and low concentrations of glucose. Cows with moderate fatty liver had overactivated inflammatory pathways in the liver, as indicated by increased abundance of phosphorylated nuclear factor κB (NF-κB) p65, NLR family pyrin domain containing 3 (NLRP3) and caspase-1 inflammasome protein, and elevated plasma concentrations and hepatic mRNA abundance of their molecular targets IL-1β, IL-6, and tumor necrosis factor α (TNF-α). In the cell culture model, we were able to replicate our findings in cows with moderate fatty liver: 1.2 mM exogenous FFA decreased the abundance of MFN2 and upregulated phosphorylation levels of the inhibitor of NF-κB (IκB) α and NF-κB p65, the IκB kinase β activity, and the abundance of NLRP3, caspase-1, IL-1β, IL-6, and TNF-α. Whereas MFN2 knockdown potentiated the FFA-induced activation of these inflammatory pathways, overexpression of MFN2 attenuated the detrimental effect of excess exogenous FFA by improving mitochondrial function and decreasing the release of reactive oxygen species, suggesting that MFN2 may be a potential therapeutic target for FFA-induced hepatic inflammation in dairy cows during early lactation.

Hepatic nuclear factor kappa B signaling pathway and NLR family pyrin domain containing 3 inflammasome is over-activated in ketotic dairy cows

Ketosis is an important metabolic disease that can negatively affect the production efficiency of dairy cows. Earlier studies have revealed metabolic and inflammatory alterations in the blood associated with ketosis; however, a link between ketosis and hepatic inflammation has not been well documented. The objective of this study was to investigate whether the nuclear factor kappa B (NF-κB) signaling pathway and NLR family pyrin domain containing 3 (NLRP3) inflammasome were activated in the liver of ketotic cows. Liver and blood samples were collected from healthy (n = 15, control group) and ketotic (n = 15, ketosis group) cows that had a similar number of lactations (median = 3, range = 2 to 4) and days in milk (median = 6 d, range = 3 to 9 d). Results showed that serum levels of fatty acids, β-hydroxybutyrate (BHB), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) were higher and glucose was lower in ketotic cows. Concentrations of serum proinflammatory cytokines IL18, tumor necrosis factor (TNF)-α, and IL1B were greater and the anti-inflammatory cytokine IL10 was lower in the ketosis group. Cows with ketosis had triacylglycerol accumulation in the liver. Upregulation of phosphorylated (p)-NF-κB and p-inhibitor of κB (IκB)α protein abundance in cows with ketosis indicated that the hepatic NF-κB signaling pathway was overactivated. The mRNA abundance of TNFA, inducible nitric oxide synthase (NOS2), IL18, and IL1B were greater and IL10 was lower in ketotic cows. More importantly, the mRNA and protein abundance of NLRP3 and caspase-1 (CASP1) along with CASP1 activity were greater in the liver of cows with ketosis. Overall, the data indicate that the onset of ketosis is accompanied by activation of the NF-κB signaling pathway and NLRP3 inflammasome, resulting in a state of inflammation.