Mastitis is still considered to be the most economically important infectious disease in dairy cattle breeding. The immune response in mammary gland tissues could help in developing support strategies to combat this disease. The role of neutrophils and macrophages in the innate response of mammary gland is well known. However, the immune response in mammary gland tissues, including levels of antimicrobial peptide transcripts, has not been well recognized. Moreover, most studies are conducted in vitro, on cell cultures, or on artificially infected animals, with analysis being done within a several dozen hours after infection. The aim of the study was to examine the in vivo transcript levels of beta-defensin and cathelicidins genes in cow mammary gland secretory tissue (parenchyma) with the chronic, recurrent and incurable mammary gland inflammation induced by coagulase-positive or coagulase-negative Staphyloccoci vs. bacteria-free tissue. The mRNA of DEFB1, BNBD4, BNBD5, BNBD10 and LAP genes, but not of TAP gene, were detected in all investigated samples regardless of the animals’ age and microbiological status of the mammary gland, but at different levels. The expression of most of the beta-defensin genes was shown to be much higher in tissues derived from udders infected with bacteria (CoPS or CoNS) than from bacteria-free udders, regardless of parity. Cathelicidins (CATH4, CATH5 and CATH6) showed expression patterns contrasting those of β-defensins, with the highest expression in tissues derived from bacteria-free udders. Increased expression of genes encoding β-defensins in the infected udder confirms their crucial role in the defense of the cow mammary gland against mastitis. On the other hand, the elevated cathelicidin transcripts in non-infected tissues indicate their role in the maintenance of healthy mammary tissues. The expression levels of investigated genes are likely to depend on the duration of the infection and type of bacteria.

Genome-wide gene expression profiling allows for identification of genes involved in the defense response of the host against pathogens. As presented here, transcriptomic analysis and bioinformatics tools were applied in order to identify genes expressed in the mammary gland parenchyma of cows naturally infected with coagulase-positive and coagulase-negative Staphylococci. In cows infected with coagulase-positive Staphylococci, being in 1st or 2nd lactation, 1700 differentially expressed genes (DEGs) were identified. However, examination of the 3rd or 4th lactations revealed 2200 DEGs. Gene ontology functional classification showed the molecular functions of the DEGs overrepresented the activity of cytokines, chemokines, and their receptors. In cows infected with coagulase-negative Staphylococci, in the 1st or 2nd lactations 418 DEGs, while in the 3rd or 4th lactations, 1200 DEGs were identified that involved in molecular functions such as protein, calcium ion and lipid binding, chemokine activity, and protein homodimerization. Gene network analysis showed DEGs associated with inflammation, cell migration, and immune response to infection, development of cells and tissues, and humoral responses to infections caused by both types of Staphylococci. A coagulase-positive Staphylococci infection caused a markedly stronger host response than that of coagulase-negative, resulting in vastly increased DEGs. A significant increase in the expression of the FOS, TNF, and genes encoding the major histocompatibility complex proteins (MHC) was observed. It suggests these genes play a key role in the synchronization of the immune response of the cow’s parenchyma against mastitis-causing bacteria. Moreover, the following genes that belong to several physiological pathways (KEGG pathways) were selected for further studies as candidate genes of mammary gland immune response for use in Marker Assisted Selection (MAS): chemokine signaling pathway (CCL2, CXCL5, HCK, CCR1), cell adhesion molecules (CAMs) pathway (BOLA-DQA2, BOLA-DQA1, F11R, ITGAL, CD86), antigen processing and presentation pathway (CD8A, PDIA3, LGMN, IFI30, HSPA1A), and NOD-like receptor signaling pathway (TNF, IL8, IL18, NFKBIA).

We examined acute phase protein (APP) concentrations in viral infections of dairy ruminants and assessed the potential role of characteristic patterns of APP changes in auxiliary diagnosing viral diseases. All viruses reviewed are common causes of farm animal diseases. APPs are among the first agents of immunity, and their concentrations could be diagnostically relevant. In the most common ruminant viral diseases, elevated serum amyloid A (SAA) and haptoglobin (Hp) levels in blood serum have been observed. However, since these proteins are the main APPs in many viral infections, it is impossible to use their levels for diagnosing particular infections. Decreased Cp and albumin expression could help differentiate the bluetongue virus infection from other diseases. Lastly, analysis of SAA levels in blood serum and milk could be helpful in diagnosing small ruminant lentivirus infection. While promising, APP levels can only be considered as an auxiliary tool in diagnosing viral diseases in ruminants.

The effects of chronic treatment with tricyclic antidepressant (desipramine, DMI) on the hippocampal transcriptome in mice displaying high and low swim stress-induced analgesia (HA and LA lines) were studied. These mice displayed different depression-like behavioral responses to DMI: stress-sensitive HA animals responded to DMI, while LA animals did not.

Insulin-like growth factor 2 (IGF2) is considered to be a regulator of post-natal growth and differentiation of the mammary gland. In the present work, associations of two single nucleotide polymorphisms in the bovineIGF2gene with milk production traits were studied in dairy Holstein-Friesian cows: the already described g.8656C>T transition in exon 2 (RFLP-BsrI) and the newly found g.24507G>T transversion in exon 10 (RFLP-HaeIII), found by sequencing 273-bp exon 10 of theIGF2gene in six individuals. Associations were analysed individually and in combination with the multi-trait repeatability test-day animal model. The CT/GT haplotype appeared to be associated with most of the milk traits studied (differences were significant atP⩽0·001). The most frequent CT/GG haplotype seemed inferior to others in fat and protein content and daily yield of fat and protein but superior (together with the TT/GG genotype) when the daily milk yield is considered.

The aim of the study was to analyze acute phase protein and cathelicidin gene responses to small ruminant lentivirus (SRLV) infection in goats. In uninfected goats, we found higher Cp and lower Fbγ mRNA levels in blood leucocytes (BL) than in milk somatic cells (MSC), as well as lower SAA, Hp, and CRP and higher Cp and AGP concentrations in blood serum than in milk. In SRLV-infected goats, we found higher Fbγ and MAP28 and lower Cp expression in MSC than in BL, and higher SAA, Hp, Fb, and MAP28 and lower AGP concentrations in milk than in blood serum. Higher SAA and Hp expressions in BL and Hp expression in MSC were found in SRLV-infected goats. In SRLV-infected goats, we observed a higher concentration of SAA in blood serum, while in milk, lower SAA, Cp, and MAP28 and higher MAP34 concentrations were observed. The expression profiles of the studied genes differed between BL/serum and MSC/milk. The elevated SAA concentration in blood serum was accompanied by a decreased concentration of SAA and Cp in the milk of infected goats. No differences in the expression of the other studied genes may mean that the SRLV has the ability to evade the immune system, continuing to replicate. The elevated concentration of SAA in blood serum may promote viral multiplication. This higher concentration of SAA in blood serum and simultaneous reduced concentration of SAA and Cp in milk may be additive indicators of this infection.