Successful management of the dairy industry is closely related to rearing healthy calves. The proper development of the gastrointestinal canal is crucial to reach this goal. One of the strategies to promote this development is the addition of feed additives to the diet. This research aimed to determine the impact of prebiotic inulin and a new, not commercially available synbiotic (mix of prebiotic inulin and probiotic S. cerevisiae strain 1026) on the development of the gastrointestinal canal of calves by comparing the weight of the stomach, its relative ratio to body weight and evaluating pH, and histological changes in different parts of the gastrointestinal canal and assess whether or not the addition of inulin to the yeast S. cerevisiae improves the abovementioned parameters. We used prebiotic inulin (6 g) and a synbiotic (prebiotic inulin 6 g and probiotic Saccharomyces cerevisiae strain 1026, 5 g). The 56-day long research was conducted with fifteen crossbreed calves (32 ± 6 days old) organized in the control group (CoG), the prebiotic group (PreG), and the synbiotic group (SynG). We determined pH, morphological parameters of different parts of the digestive canal, and morphometric parameters of the stomach. The addition of prebiotic inulin to calves’ diet causes the increase of pH in rumen, abomasum, and intestines but when inulin was added to S. cerevisiae, pH decreased and was even lower than in the control group. Prebiotic inulin and its synbiotic with yeast S. cerevisiae positively impact the development of almost all morphological structures of rumen saccus dorsalis, rumen saccus ventralis, and intestine; moreover, calves from the synbiotic group showed better results in virtually all parameters. However, both inulin and synbiotic did not affect the weight and relative weight of different parts of the stomach. Tested synbiotic has the potential to promote the development of the rumen and other parts of the digestive canal of calves.

Since milk whey is an abundant dairy by-product and a significant threat to the environment, its utilization is of great interest. The study compares valorization of lactose and lactates—the main carbon sources of whey—by fermentation—an environmentally friendly process. Antimicrobials released during fermentation by food-grade bacteria can help increase the microbiological safety of food. Propionic acid—a strong antimicrobial—is obtained mainly by the petrochemical route, yet there is increasing interest in its synthesis in biotechnological pathway. Five strains of propionic acid bacteria (Acidipropionibacterium acidipropionici, Propionibacterium cyclohexanicum, Propionibacterium freudenreichii, Acidipropionibacterium jensenii and Acidipropionibacterium thoenii) were investigated for their ability to produce organic acids and biomass using Na lactate or lactose as carbon sources. Selected fermentates were investigated for their antimicrobial efficacy during in vitro studies with foodborne pathogens: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus. Results confirm that the production of acids and biomass is considerably influenced by the added carbon source. The tested fermentates have strong and specific antimicrobial activity against Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus. In addition, inhibition of Staphylococcus aureus and Klebsiella pneumonia depends on the activity of produced bacteriocins. The article also discusses the possibility of increasing the antimicrobial activity of fermentates by acidification.

Aim:The aim of the research was to evaluate the growth performance, to measure the amount of methane (CH4) and carbon dioxide (CO2) in calves’ rumen, and to compare the obtained results between the control group (CoG) and the experimental group (Pre12) which received the additional supplement of the prebiotic inulin.Materials and Methods:The research was conducted with ten Holstein Friesian (Bos taurus L.) crossbreed calves with an average age of 33±6 days. Calves were split into two groups: 5 calves that were fed with the control non-supplemented diet (CoG) and 5 calves that were fed with the same diet further supplemented with 12 g of flour of Jerusalem artichoke (Helianthus tuberosus L.) containing 6 g of prebiotic inulin per 0.5 kg of barley flour diet (Pre12). The duration of the experiment was 56 days. CH4 and CO2 were measured using cavity ringdown spectroscopy device Picarro G2508. The weight and samples from calves’ rumen were evaluated 3 times during the experimental period - on the 1st, 28th, and 56th days. Samples were obtained by puncturing the calf rumen.Results:The weight gain (kg) during the whole experimental period was higher in the Pre12 (65.8±6.57) compared to CoG (36.8±7.98) calves (p<0.001). The daily weight gain was also increased in the Pre12 (1.2±0.12) than CoG (0.7±0.14) calves (p<0.001). There was no difference in the levels of CH4 and CO2 produced in the rumen of CoG and Pre12 calves (p>0.05).Conclusion:The main results showed that the prebiotic inulin can promote weight gain in calves, without affecting the mean concentration of CH4 and CO2 in calves’ rumen.

Aim: The research aimed to determine the impact of synbiotic: 6 g of prebiotic inulin and 5 g of probiotic Saccharomyces cerevisiae strain 1026 on calves' productivity and greenhouse gas (GHG) production. Materials and Methods: The research was conducted with 10 Holstein Friesian and Red Holstein (Bos taurus L.) crossbreed calves of mean age 33±6 days and initial body weight 73.4±12.75 kg. We added the synbiotic into the diet of five dairy crossbreed calves (SynG) and five calves in control group (CoG) received non-supplemented diet. The duration of the experiment was 56 days. The weight of calves and amount of methane (CH4) and carbon dioxide (CO2) in the rumen were determined on day 1, 28, and 56. On day 56, three calves from each group were slaughtered. Meat samples were assessed for some indicators of meat quality. The main methanogens were detected in the rumen fluid and feces. Results: The weight gain during the whole experiment period of 56 days was higher in the SynG (62.6±13.75 kg) compared to CoG (36.8±7.98 kg) calves (p<0.01). There were no significant differences in the levels of protein (%), fat (unsaturated and saturated – %), and cholesterol (mg/100 g) in meat samples from both groups. At the end of the experiment, the amount of CH4 in calves' rumen in CoG was higher (Me=792.06 mg/m3, interquartile range [IQR] 755.06-873.59) compared to SynG (Me=675.41 mg/m3, IQR 653.46-700.50) group (p<0.01). The values for CO2 were also increased in CoG (Me=4251.28 mg/m3, IQR 4045.58-4426.25) compared to SynG (Me=3266.06 mg/m3, IQR 1358.98-4584.91) group (p=0.001). There were no significant differences in the calves' weight and certain methanogen species in rumen liquid and feces on the 56th day of the experiment. Significantly higher results in the parameter total prokaryotes (V3) (bacteria+archaea) in rumen fluid were in SynG, whereas significantly higher results in the parameter total methanogens Met630/803 in rumen fluid were in CoG, p<0.05. Conclusion: The main results showed that the synbiotic can increase the daily weight gain in calves and decrease the amount of GHG in rumen but does not impact different methanogen species in rumen liquid and feces and meat protein, fat, and cholesterol levels.

Species-specific microenvironmental preferences and interactions between parasite species have been the focus of many ecological studies. Here, we studied the distribution of ectoparasite species within the gill apparatus of bream (Abramis brama) from Lake Lubāns (Latvia) to establish whether digenean metacercariae: (1) prefer specific patches within the gill apparatus; (2) co-occur in the same patches with monogeneans and copepods within a host individual; and (3) interact with monogeneans and copepods. We recorded all parasites on gill arches of the same host species and used null models to analyse co-occurrences of digenean metacercariae, monogeneans and copepods. Zero-inflated mixture models were used to define the preferred patches of parasites. We found that digenean metacercariae (Bucephalus polymorphus) prefer specific patches of the gill apparatus to encyst, and shared these preferences with monogeneans and copepods, but did not interact with them. We concluded that digenean metacercariae have a species-specific microenvironmental preference to encyst in the gill apparatus and their occurrence (even in high numbers) does not reduce the success of attachment of monogeneans and copepods in the same gill patches.

The development of new methods of crop production is the most promising field of research in agriculture. There are numerous chemical techniques of seed treatment before sowing; however, mollusc mucus has not been considered as a natural alternative of seed treatment yet. In this study, we treated sweet pepper seeds with Spanish slug mucus before sowing. Seed germination success, germination time, as well as the performance of seedling growth were compared between experimental and control groups. The main result showed that seeds treated with slug mucus required significantly fewer days to germinate than seeds without treatment. Although treated seeds exhibited faster germination, seedlings showed slower growth than in the control group. No significant difference of seed germination success between the control and experimental group was found.

Aim: The research aimed to test the association between the level of immunoglobulin G (IgG) in bovine colostrum and calf blood serum and to evaluate its relation to Cryptosporidium spp. invasion in calves. Materials and Methods: Fresh colostrum and fecal specimens from cows (n=114) as well as blood and fecal specimens from newborn calves (n=114) were collected in the dairy cattle farm. Investigated calves were separated from their mothers directly after birth and received 2 L of colostrum in two separate feedings within the first 24 h. Blood samples were taken from calves at the age of 2 days. Coprological samples were taken from calves at the age of 1, 10, and 15 days. Both colostrum and fecal samples from cows were taken on the 1st day after calf birth. Rectal fecal samples were collected separately from each calf and cow into plastic bags. The collected calf serum samples and bovine colostrum samples were tested for bovine IgG by competitive enzyme-linked immunosorbent assay kit bovine Ig. To record oocysts of Cryptosporidium spp. in feces, the flotation method was used. Binomial logistic regression was performed to ascertain the effects of IgG in bovine colostrum and calf blood serum on the likelihood of Cryptosporidium spp. infection in calves. Results: The concentration of IgG in bovine colostrum was higher (70.7±26.6 g/L, mean±standard deviation) than that in calf blood serum (13.2±6.1 g/L); the statistically significant difference was 57.4 g/L (95% confidence interval, 52.4-62.4), t (124.872)=22.536, p<0.001. Mann–Whitney's U-test showed a significant difference between samples collected on days 10 and 15 of the experiment (U=1944, z=2.330, p=0.020). The higher number of oocysts in calf feces was recorded on day 15 (median=6.5) compared to day 10 (median=4). The prevalence of calf infection from days 10 to 15 increased from 26.3 to 45.6% and was at least 3 times higher than in cows. A statistically significant positive correlation was recorded between IgG concentration of cow colostrum and calf blood serum (r (114)=0.414, p=0.001), whereas a correlation between the concentration of IgG and the intensity of Cryptosporidium spp. infection was not recorded (p>0.05). The logistic regression model was not statistically significant (χ2(2)=0.013, p=0.99 (10 days) and χ2(2)=0.100, p=0.95 (15 days)). Conclusion: Mother passive transfer of immunity to the offspring through colostrum does not influence the susceptibility of calves to Cryptosporidium infestation.

The use of international nonproprietary names (INNs) has been mandatory for prescriptions of state-reimbursed drugs in Latvia since 1 April 2020. In a retrospective analysis, we aimed to examine the impact of the new regulation on changes in the prescribing and dispensing practice of antihypertensive agents with an example of bisoprolol or/and perindopril and their combinations. All state-reimbursed bisoprolol and/or perindopril prescriptions for arterial hypertension were evaluated in two time periods: 1 April 2018 to 31 March 2019 and 1 April 2020 to 31 March 2021. The proportion of INN prescriptions increased from 2.1% to 92.3% (p < 0.001, φ = 0.903). The rate of fixed-dose combinations (FDCs) increased from 60.8% to 66.5% (p < 0.001, φ = 0.059). The rate of medication errors was 0.6%. The most common (80.6%) error was that the dispensed medicine dose was larger or smaller than indicated on the prescription. In addition, prescribing an FDC medicine increased the chance of making an error by 2.5 times on average. Regulatory changes dramatically affected the medicine-prescribing habits of INNs. The increase in FDC prescription rates may align with the recommendations of the 2018 ESC/ESH guidelines. The proportion of total errors is estimated as low, but control mechanisms are needed to prevent them.