The aim of this study was to evaluate the effect of zinc (Zn) supplementation in different commercial forms on the growth performance, health status, and Zn balance of weaners in field conditions. The animals were fed pre-starter (from the 28th to 47th day of life) and starter (from the 48th to 74th day of life) mixtures differing in Zn form and concentration. Group I was given ZnSO₄ at 150 mg kg⁻¹; Group II received pre-starter zinc oxide (ZnO) at 3000 mg kg⁻¹ and starter at 150 mg kg⁻¹; and Group III was given 150 mg kg⁻¹ of zinc oxide nanoparticles (nZnO). We found that the average daily gain in Group I was significantly lower, compared to Groups II and III. A commonly accepted level of Zn (150 mg kg⁻¹) as nZnO can be recommended, instead of therapeutic doses of Zn preparations with the same efficiency. Moreover, a lower level of Zn in the diet can prevent the excessive accumulation of this element in waste and, thus, reduce environmental damage.

Struvite is regarded as a promising phosphorus (P) fertilizer compared to commercial pristine mineral phosphorus fertilizers. The aim of this study was to determine the effect of Phosgreen fertilizer, with struvite as its phosphorus source, on the chlorophyll, potassium (K), and calcium (Ca) contents in lettuce grown in peat compared to superphosphate. The study was carried out as a pot experiment with different doses of P fertilization. The study presents the chlorophyll a, b, total (a + b) chlorophyll, and carotenoid contents of the lettuce plants. Significant differences in the chlorophyll a and b contents were observed between the different phosphorus applications, and this can have a direct impact on the crop yields. Significantly higher contents of both chlorophyll contents were observed under Phosgreen fertilization as well as the chlorophyll a + b content *. The results of the study on lettuce indicate a dependence of vitamin C content on phosphorus fertilizer, but with no significant increase under Phosgreen fertilization; the contents of K and Ca were not significantly dependent on the type of phosphorus fertilizer. Due to the favorable composition of Phosgreen, it may be recommended for use as a phosphorus fertilizer in the agriculture and horticulture sectors.

This study aimed to determine the effect of the addition of oat hull (0–3%) and high amounts of cereal grains to the diet of broiler chickens in terms of the development of the upper gastrointestinal tract, individual microbial counts in the crop and ileum, and the effect of dietary fibre fractions on microbial changes from the beak to the ileum. In the 28 d trial, 162 one-day-old Hubbard Flex male chickens with an average body weight of 44.5 g were randomly allocated to 27 metabolic cages. The experiment consisted of a randomised, one factorial ANCOVA design composed of a covariate with two ANOVA factorial designs containing nine treatments (3 × 3): three sources of cereal grains (maize, wheat, and barley, with a minimum amount of 500 g · kg⁻¹, each with nine replications) and three levels of oat hull (0, 1, and 3%, each with nine replications). At the end of the study, 81 chickens (9 in each treatment) were slaughtered to determine the weight of the individual organs and characterise the intestinal microbiota. The application of 3% oat hull to the cereal diets increased the weight of the proventriculus and the gizzard (6.3 and 27.3 g, respectively) in comparison to diets without the addition of this structural component (6.0 and 23.7 g). Higher crop counts of total aerobic microbes (6.29 log CFU · g⁻¹) and Lactobacillus spp. (4.05 log CFU · g⁻¹) were observed in diets containing wheat grain compared with maize (4.62 and 3.55 log CFU · g⁻¹, respectively). The main reason for the microorganism’s growth (p < 0.05) was the amount of soluble dietary fibre and hemicelluloses present in the diet: total aerobic microbial count (respectively r = 0.918 and r = 0.816) and Lactobacillus spp. (respectively r = 0.416 and r = 0.442). Barley diets decreased (p < 0.05) E. coli counts in the ileum (2.69 log CFU · g⁻¹) vs. maize and wheat diets (3.41 and 3.45 log CFU · g⁻¹, respectively), mainly due to the increase in the amount of insoluble dietary fibre in the diet (r = −0.462). Reduced total yeast and mould counts in the ileum were also observed (p < 0.05) in connection with the presence of soluble dietary fibre and hemicelluloses in diets (r = −0.397 and −0.398, respectively).

Previous research indicated the potential use of struvite (STR) as an alternative source of phosphorus (P) in crop production. A greenhouse experiment was conducted to evaluate the effect of STR and triple superphosphate (TSP) on the growth and chemical composition of butterhead lettuce grown on peat substrate over a three-month period (May–July). Both alternative (STR) and conventional (TSP) fertilizers were applied at three rates: (1) recommended rate based on the elemental content of substrate and crop nutritional need; (2) reduced rate (50% lower than recommended); and (3) increased rate (50% higher than recommended). Unfertilized (control) plants were also grown in the pot experiment. As expected, fertilizer application tended to increase the content of heavy metals in the substrate. Thus, an increase in Zn, Pb, and Cu content in peat substrate was found following STR amendments. However, compared with unfertilized plants, the applied rates of the STR and TSP fertilizers did not increase the content of Cd and Cu in the plant leaf, while Hg content was below the detection limit. In addition, Zn content in the plant leaf significantly decreased following STR and TSP applications. In comparison to unfertilized plants, both alternative and conventional fertilizers increased the content of P and nitrate nitrogen (N-NO₃⁻) in the plant leaf while their effect on Mg content was negligible. The increased rate of STR was the best fertilizer treatment because it produced the largest number of leaves, which were also characterized by the highest P content. Our findings showed that STR was an effective source of P in butterhead lettuce cultivation without adverse effects on heavy metal accumulation.

Guizotia abyssinica (Guizotia abyssinica (L.f.) Cass.) is regarded as a minor oilseed crop, which is important in terms of its nutritional value and potential uses. An important benefit of this crop is its cultivation for green matter and seed yield even under the difficult conditions of marginal cultivation. Guizotia abyssinica has not yet gained popularity in Europe. However, in a changing climate and taking into account its feeding value, it could gain in importance for ruminant nutrition in the near future. A field experiment was conducted in 2018 and 2019 in the west part of Poland on a farm in Opolskie voivodship (commune Prudnik). The objective of the field study was to assess the effect of three harvest dates on the yield and the chemical composition of fodder in a 90-day cultivation cycle in each year of the study. Stage of growth seems to be the most important factor affecting yield and the chemical composition of Guizotia abyssinica. In both years of the research, the green fodder yield reached the highest value after 90 days from sowing—32.5 and 36.9 t ha⁻¹—while dry matter was 6.85 and 7.99 t ha⁻¹, respectively. Chemical composition was also significantly dependent on harvesting date. Crude protein (in 2018 from 154.5 to 100.7 g kg⁻¹ and in 2019 from 148.3 to 78.2 g kg⁻¹) and crude ash (in 2018 from 165.8 to 98.7 and in 2019 from 155.2 to 89.9 g kg⁻¹) content decreased with progressive harvest date while nitrogen-free extracts (in 2018 from 500.5 to 562.0 g kg⁻¹ and in 2019 from 582.2 to 605.2 g kg⁻¹) and gross energy increased (in 2018 from 19.4 to 21.17 MJ kg⁻¹ and in 2019 from 18.63 to 19.73 MJ kg⁻¹.). The most favorable date for harvesting green forage is 90 days after sowing, due to the significantly highest yield of fresh and dry matter of green forage and with potential as a forage for animals.

The purpose of the experiment was to determine the effect of oat hull on the performance and morphometric measurements of the gastrointestinal tract, and to correlate the results of these measurements with the type of the determined dietary fiber in feed and the number of microorganisms. The Asp method is simpler and quicker than non-starch polysaccharide analysis, and can give quick information in the analysis of fiber fractions (soluble and insoluble) in the component or in a diet, and also related the obtained results with the performance of broiler chickens. The utilization of oat hull in the amount of 1% of the diet of broiler chickens results in the highest body weight on the 28th day of life (p < 0.05) in comparison to the group not receiving oat hull in the diet and with a 3% share of this structural component. Oat hull in the diet of broiler chickens in the amount of 1% also reduces the total length of the intestines (p < 0.05), compared with the share of 0 and 3%. The soluble fiber contained in the grains of barley and wheat has an influence on the higher metabolic weight of the glandular stomach of broiler chickens compared to the birds receiving corn grain in their diet. Barley grain and oat hull in the amount of 3% significantly (p < 0.01) increase the weight of gizzards. The increase in the weight of the proventriculus (r = 0.392), gizzard (r = 0.486) and duodenum (r = 0.657) was positively correlated with the growth of E. coli bacteria in the crop. The opposite effect in the case of negative correlation was determined in the case of the duodenum and E. coli count (r = −0.593).