Comparative Analysis of Methods for Somatic Cell Counting in Cow's Milk and Relationship between Somatic Cell Count and Occurrence of Intramammary Bacteria

The aim of this study was to compare three on-farm commercial methods for the indirect detection of subclinical mastitis in dairy cows: the California mastitis test (CMT), the Porta side somatic cell count milk test (Porta SCC), and the DeLaval cell counter (DCC), with the Fossomatic cell count (FSCC), and to evaluate the relationship between the determined somatic cell count SCC and the occurrence of intramammary pathogens in the milk of dairy cows. A total of 284 sensory unchanged mixed milk samples, collected during the milking on a dairy farm, were analyzed in this study for somatic cell counts by the mentioned on-farm tests. Quarter milk samples (n = 583) from all the selected cows were cultured. The agreement, sensitivity, and specificity of the three indirect commercial diagnostic tests (the CMT, the Porta SCC, and the DeLaval cell counter) were calculated, and the FSCC was used as the gold standard. The results were analyzed statistically using the Pearson correlation test and the paired t-test. The CMT matched with the FSCC in 83.1% of the samples, with the Porta SCC in 80.6%, and with the DCC in 80.3% of the samples. The sensitivity and specificity reached 81.0% and 92.9% for the CMT, 79.4% and 90.7% for the Porta SCC, and 75.8% and 97.5% for the DCC, respectively. The correlation between the FSCC and the Porta SCC was 0.86 (p < 0.0001), and between the FSCC and the DCC, it was 0.92 (p < 0.0001). The differences between them were insignificant. Bacteria were detected in 130 (22.3%) quarter milk samples. The most prevalent bacteria were Enterococcus spp. (36.2%), followed by E. coli (20%), coagulase-negative staphylococci (13.1%), A. viridans (9.2%), Streptococcus spp. (9.2%), Proteus spp. (6.2%), and S. intermedius (3.9%). Contagious isolates (S. aureus) were detected in 3 quarter milk samples (2.3%). The agreement between the individual tests and the microbiological culture was as follows: 69.2% for the CMT; 73.7% for the Porta SCC; 71.6% for the DCC; and 76.5% for the FSCC. Higher SCCs were detected in the milk samples contaminated with bacteria than in the healthy milk (p < 0.001). No significance was found between the presence of individual species of intramammary pathogens and the different levels of SCCs. Based on the results, bacteria are the predominant cause of subclinical mastitis. The increased SCC of some milk samples with no presence of bacteria meant that the increase could have been caused by numerous other agents (viruses, fungi, or algae) or factors for mastitis in the dairy industry.

Antibacterial activity, quality and stability study of creams with new potential silver(I) complexes and in vivo case report

The aim of this study was to evaluate the antibacterial activity, quality and stability of creams (at 1 % concentration) prepared with synthesized silver(I) complexes: [Ag(Nam)₂]NO₃·H₂O ( AgNam), [Ag₂(HGly)₂]_n(NO₃)_2n (AgGly) (Nam - nicotin-amide, Gly - glycine) and silver(I) sulfadiazine (AgSD), which is commercially available. Antibacterial activity was evaluated by agar well diffusion method and in in vivo case. The pure silver(I) complexes as well as all three tested creams loaded with AgGly, AgSD and AgNam showed antibacterial potential. Moreover, the creams loaded with AgGly and AgNam showed higher antibacterial effects against S. aureus and B. subtilis than the cream loaded with AgSD. In terms of appearance, all cream samples were opaque and odourless, and no phase separation was observed. Creams were soluble in water (o/w emulsions) and they had a pseudoplastic behaviour. The pH of the creams was in the range of 4.87-5.75. No visible changes were observed in the case of commercially used AgSD cream during one month testing period at conditions -16 ± 1 °C; 6 ± 1 °C and 56 % relative humidity; 20 ± 1 °C and 58 % relative humidity and 40 ± 1 °C and 75 % relative humidity. However, creams containing AgGly and AgNam changed their colour depending on the tested conditions.

The Presence of Treponema spp. in Equine Hoof Canker Biopsies and Skin Samples from Bovine Digital Dermatitis Lesions

Equine hoof canker and bovine digital dermatitis are infectious inflammatory diseases of the hooves with an unknown etiology. However, anaerobic spirochetes of the genus Treponema are considered to be potential etiological agents. The aim of this study was to find a suitable way to isolate DNA and to detect the presence of treponemal DNA in samples of equine hoof canker and bovine digital dermatitis. DNAzol^®® Direct and column kits were used to isolate DNA from samples of equine hoof canker and bovine digital dermatitis. The presence of Treponema spp. was detected using PCR and Sanger sequencing. DNAzol^®® Direct is suitable for isolating DNA from these types of samples. Treponemal DNA was detected in equine hoof samples as well as in bovine digital dermatitis skin samples. In equine hoof biopsies, the most frequently detected was Treponema pedis (8/13). Treponema brennaborense (2/13) and Treponema denticola (2/13) were also found. In the case of bovine digital dermatitis, Treponema medium ssp. bovis was confirmed in 14 of 36 skin samples. Treponema pedis (9/36), Treponema vincentii (1/36), Treponema phagedenis (1/36), and Treponema brennaborense (1/36) were detected as well. DNAzol^®® Direct was more appropriate for isolation of treponemal DNA because the columns isolation method was more equipment and time-consuming. The presence of several Treponema spp. was determined in the samples. In horses, the most commonly detected species was a T. pedis, while in cattle it was T. medium ssp. bovis.

Effect of humic acids on lead poisoning in bones and on a subcellular level in mitochondria

Humic acids (HA) are natural substances which exhibit a remarkable spectrum of health benefits, such as their role in chelation. This study aims to supplement the current knowledge on the chelating effects of HA in chronic lead intoxication in rat femurs and in liver, heart and kidney mitochondria in an experiment lasting 10 weeks. Lead acetate trihydrate was administered to rats for 5 weeks at a daily dose of 155.5 mg/kg body weight. At the same time, rats were given three concentrations of HA, with their effect measured over the following 5 weeks. Increased Pb concentrations were detected in the femur after the first week, while HA-administered groups showed a tendency towards inhibiting the increase in Pb deposition. After 5 weeks, Pb concentrations dropped significantly in the HA groups. At the same time, however, other elements were redistributed, with a decrease in Se and Zn being particularly noteworthy. While an increase in Pb concentrations was found after 5 weeks of Pb administration, a concentration of 1% HA resulted in the least significant increase in Pb as well as an increase/decrease in Se/Cu, respectively. In mitochondria, an increase in Pb content was detected after the first and fifth weeks with concomitant redistribution of other elements. At the end of the experiment, again in the 1% HA group, Pb concentrations remained higher only in the liver with the other elements sufficiently normalized, indicating this concentration to be useful in the treatment of Pb intoxication.

Effects of Humic Acids in Chronic Lead Poisoning

Chronic exposure to lead causes disruption to energy production mechanisms and tissue damage, in particular through its binding to thiol groups and competition for zinc binding sites. We investigated the possibility of preventing the consequences of chronic lead poisoning by administration of three different doses of humic acids (HAs) into feed with the aim of establishing an effective HA dose. During the 10-week experiment, a sub-lethal dose of lead acetate was given to rats during the first 5 weeks, with continuous administration of HA over 10 weeks. Measurements were taken to determine the content of the metals Pb, Mn, Cu, Fe and Zn; the metalloid Se; and selected antioxidant markers in the heart, liver, kidney and plasma after the first, fifth and tenth weeks of experiment. The administration of lead and HAs clearly affects the redistribution of the elements and the activity of the antioxidant enzymes. This fact was particularly highlighted in the lead-only group as, within the experiment, significantly higher Pb concentrations were found only in the plasma of this group. However, in the group with 1% HA administered with lead, we observed a rise in Zn concentrations in the organs and the deposition of Fe into the liver. Decreased glutathione reductase activity in the plasma and balanced reduced glutathione concentrations indicated sufficient efficiency of redox reactions. SOD activities were among those affected most strongly, with only the 1% HA group showing no effect on heavy metal redistribution as a result of HA administration.

Prevalence of Claw Diseases in Dairy Cows with Different Body Condition

The aim of this study was to examine the relationship between body condition and claw diseases in dairy cows. The data used in this study were obtained during two sessions of routine orthopaedic treatment and hoof trimming on a dairy farm in Eastern Slovakia. In the spring and autumn terms, 482 dairy cows were examined for claw diseases and their body conditions were recorded. Out of the 482 dairy cows, 56 % were affected by one or more claw diseases in one or more legs. Digital dermatitis and sole ulcers were the most often detected claw diseases found in this study. The dairy cows with a low body condition score (BCS < 3) showed a higher prevalence of claw diseases (P < 0.05) than the cows with a body condition score greater than 3. However, this difference could not be found when infectious diseases of the claws (digital dermatitis, foot rot, and interdigital dermatitis) were analysed. The results of this study allowed us to conclude that the dairy cows with a lower grade of body condition suffered more from non-infectious claw diseases (sole ulcer, white line diseases).

The electrophoretic pattern of serum proteins in dairy cows with inflammatory diseases

The objective of the study was to evaluate the electrophoretic pattern of serum proteins in dairy cows suffering from various inflammatory diseases, and to study the influence of these diseases on the concentrations of protein fractions. Fourty dairy cows with clinical signs of various inflammatory diseases were used in the study, including cows with post-partum metritis (n=10), mastitis (n=7), and hoof diseases (n=23). The cows were of a black pied Holstein-Friesian breed, Slovak spotted breed and their crossbreeds at the age of 3.5 to 8 years. Fourteen clinically healthy dairy cows were taken as the control group. The cows were blood sampled for the determination of total serum proteins and serum protein fractions. The protein fractions were divided into albumin, α1-, α2-, β1-, β2-, and γ-globulins. In cows with post-partum metritis we found significantly lower concentrations of albumin (P<0.001) and significantly higher values of α1-globulins (P<0.01) compared with healthy animals. Significantly higher concentrations of β1-globulins were observed in cows with mastitis (P<0.001), while the γ-globulin fraction was non-significantly higher. In cows with hoof diseases we recorded significantly lower values of albumin (P<0.001), significantly higher concentrations of α1- and β1-globulins (P<0.001), and non-significantly higher β2- and γ-globulins. Moreover, in the electrophoretic pattern of serum proteins we found β-γ bridging in thirteen cows with hoof diseases. Presented data suggest marked influence of inflammatory diseases on the concentrations of serum protein fractions in dairy cows. However, further investigations are needed to establish the diagnostic utility of serum protein electrophoresis in bovine clinical practice in relation to inflammatory diseases.

Effects of Manure Bedding on the Rate of Claw Diseases in Dairy Cows

This study was conducted to determine the prevalence of claw diseases in dairy cows housed on two different bedding systems: deep straw bedding and unsterilized recycled manure solids. On the farm (farm A) with the straw bedding, 403 and on the farm (farm B) with manure solid bedding, 226 dairy cows were examined. The prevalence of cows with one or more claw lesions on the farm with straw bedding and with manure solids were 37 % and 69 %, respectively (P < 0.001). In both bedding systems, two claw lesions dominated: digital dermatitis and inflammatory disorders of corium (white line diseases, toe ulcer, and sole ulcer). The prevalence of the digital dermatitis housed in deep-bedded freestalls and in freestalls with manure solids were 17.8 % and 53.1 % (P < 0.001), respectively. The prevalence of the white line diseases and toe ulcer were 12.1 % and 15.7 % on farm A and 3.88 % and 2.59 % on farm B, respectively (P < 0.001). There was no significant difference in the prevalence of the sole ulcer between farms. These data indicate a relatively high prevalence of claw lesions on the studied dairy farms. Moreover, a long-term contact of claws with manure (boxes and corridors) on the farm with unsterilized recycled manure solids seems to be associated with a higher prevalence of digital dermatitis.