Volume 18 (2018): Issue 2 (May 2018)

Urea is used as non-protein nitrogen in the rations of ruminants as an economical replacement for feed proteins. Urea transferred from the blood to the rumen is also an important source of nitrogen for rumen microbial growth. It is rapidly hydrolyzed by rumen bacterial urease to ammonia (NH₃) and the NH₃ is utilized for the synthesis of microbial proteins required to satisfy the protein requirements of ruminants. Urea has commonly become an accepted ingredient in the diets of ruminants. In recent decades, urea utilization in ruminants has been investigated by using traditional research methods. Recently, molecular biotechnologies have also been applied to analyze urea-degrading bacteria or urea nitrogen metabolism in ruminants. Combining traditional and molecular approaches, we can retrieve better information and understanding related to the mechanisms of urea metabolism in ruminants. This review focuses on urea utilization in ruminants and its regulation by rumen bacterial urease in the host. The accumulated research provides foundations for proposing further new strategies to improve the efficiency of urea utilization in ruminants.

The global animal productivity should proportionally increase to meet the food needs of a growing population. This article presents an overview of the current and promising nano-applications in poultry and livestock production systems that could offer opportunities for improved efficiencies and productivity. Some basic information on nanotechnology and the economics of nanotechnology is provided. Poultry and animal production systems, current situation and available tools and techniques are presented in parallel with animal health care, animal nutrition, animal shelter and food processing nano-applications and their advantages. These applications are directly or indirectly related to the human food chain and may affect the food safety and food quality. Lastly, the expected risks and hazards related to nano-application in poultry and livestock production systems that can affect animal, human and environment are described. It is concluded that nanoapplications have the potential to provide smarter solutions for various applications in the poultry and livestock production systems, which can help in reducing costs and enhancing the final product quality. However, concerns over safety of some nano-applications hamper their immediate implementation. Extensive risk assessments should be conducted to ensure the safety of the nanoproducts before making them available for animal or human use.

The use of probiotics as alternatives to antibiotics for farm animals is gaining more and more interest during recent years. Probiotics are living microorganisms that provide a wide variety of health benefits to the host when ingested in adequate amounts. The bacterial strains most frequently used as probiotic agents are Bacillus, lactic acid bacteria, Enterococcus and Saccharomyces cerevisiae. It has been suggested that multi-strain probiotics might be more effective than mono-strain probiotics due to the additive and synergistic effects, and many previous studies demonstrated that dietary complex probiotics supplementation had growth promoting effects on pigs. However, the effect of complex probiotics in practice is not always consistent, the effect of probiotic could be affected by strain composition, dosage, feed formula, and the age of animals. In this review, we will give an overview on the current use of complex probiotics for weaning, growing and finishing pigs and sows.

Decreasing fertility in dairy cows, especially in the highest yielders, may be due to excessive metabolic burdens placed on their bodies. Many authors attribute decreasing reproductive efficiency in high-yielding cows to energy deficiencies in early lactation and to associated metabolic and hormonal disorders. The complexity of the issues involved in the efficient reproductive management of cows and the scientifically and practically important understanding of factors affecting fertility in high-producing cows mandate continuous updating of existing knowledge. The aim of this study was to present the effect of postpartum endocrine function, metabolism, and mastitis on fertility in high-yielding cows. Gaining insight into these mechanisms and their relationships with factors such as nutrition and milk yield appears to be crucial for improving dairy cow fertility.

Gremlin (GREM1, GREM2) genes are the known bone morphogenetic proteins (BMPs) inhibitors, but their genetic diversity in animal species remains unknown. The current study was conducted to investigate single nucleotide polymorphisms (SNPs) in chicken GREM1 and GREM2 genes, and their association with egg production traits using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and deoxyribonucleic acid (DNA) sequencing. The results discovered novel SNPs and, among these variations, C/T transition at position 436 in exon 1 of the GREM1 gene leads to synonymous substitution of amino acids, and T/C transition at position 690 in the coding region of the GREM2 gene leads to a non-synonymous substitution of amino acids (valine acid 114-to-alanine acid). Association analysis established that at the age of 43, 57 and 66 wks, hen-house egg production (HHEP) was more highly significantly associated (P<0.05) with the AA genotype in the GREM1 gene. In the GREM2 gene, the TC genotype was remarkably linked with higher HHEP at the age of 30, 57 and 66 wks. Our results provide evidence that the GREM1 and GREM2 genes have potential effects on HHEP in chickens. SNPs determined in this work may be utilised as favourable potential DNA markers for improving of egg-laying performance traits.

For many years, research has been undertaken to identify genetic markers associated with reproductive traits in pigs, but these issues are still open to research. WNT7A expression was found in endometrium during embryo implantation as well as in early pregnancy in humans and in different species of animals. Our study was designed to identify polymorphic changes in the WNT7A gene and their effect on reproductive traits in 480 Polish Large White (PLW ) and Polish Landrace (PL) pigs in 4 successive litters. As a result, 3 mutations were identified: two transitions in exon 3 g.6270G>A (rs326274214) and in intron 4 g.36251G>A (rs321204163) and deletion/insertion in intron 4 g.36220delinsAT (rs338143418). Frequency analysis of the genotypes of these polymorphisms in the WNT7A gene showed departure from Hardy-Weinberg equilibrium for PLW at locus g.36220delinsAT and for total breeds and PLW at locus g.36251G>A. Generally, the largest litters were found in sows with AA genotypes for mutations g.6270G>A and g.36251G>A and in sows with ins/ins genotype for mutation g.3622delinsAT . However, the sows of these genotypes formed only a small percentage (from 9% to 13%) in the studied group of animals. Statistical analysis showed significant differences only for the number of piglets born and reared in parity 1 (1NBA and 1N21d) in favor of the sows with genotype AA g.6270G>A (P≤0.05) and for the number of piglets born in litter 4 (4NBA) with genotype ins/ins g.3622delinsAT (P≤0.05). The analysed mutations had no effect on the age at first farrowing and the successive farrowing intervals.

Two experiments were conducted to evaluate the effects of humic acids (HA) on recovery of Salmonella Enteritidis, in an in vitro digestive system and on intestinal colonization in neonate broiler chickens. In experiment 1, two runs using an in vitro digestion model with two sources of HA (commercial or natural extraction) at 0.1 or 0.2%, and inoculated with 107 CFU/tube of S. Enteritidis, were carried out. In experiment 2, one-day-old male broiler chickens were randomly allocated to one of two groups (n=25) with or without 0.2% of isolated HA from worm compost, and challenged with 106 CFU of S. Enteritidis per chicken at 10-d old. All chicks were euthanized 24-h post challenge, and were subjected to serum fluorescein isothiocyanate dextran (FITC-d) determination. A section of ileum was removed to obtain total concentration of IgA. Ceca-cecal tonsils were removed to evaluate Salmonella recovery, total lactic acid bacteria (LAB) and total Gram negative bacteria. In experiment 1, neither concentration of commercial nor natural HA were able to reduce the recovery of S. Enteritidis in any of the simulated compartments (P>0.05). Only the crop compartment showed significant differences in pH in both trials between control and treated groups. In experiment 2, no significant differences were observed in serum concentration of FITC-d, intestinal IgA, S. Enteritidis recovery, LAB or total Gram negative bacteria in the ceca between control and treated chickens. In conclusion, no effects of HA on recovery of Salmonella Enteritidis, in an in vitro digestive system and on intestinal colonization of Salmonella, bacterial counts in ceca, intestinal IgA and serum FITC-d in neonate broiler chickens were observed. Further studies to evaluate the effect of HA under feed restriction model as an inducer of intestinal inflammation are currently being conducted.

The purpose of the study was to verify the hypothesis that there are doses of silver nanoparticles (Ag-NPs) that improve immune defence in chickens without compromising their health. To verify this hypothesis, an attempt was made to determine which doses of Ag-NPs (5 nm) consumed by chickens as a result of administration of hydrocolloids during varying time periods at a concentration of 5 or 10 mg Ag/l stimulate immune defence. The experiment was performed on 296 chickens assigned to 3 treatments. Chickens from the control treatment received drinking water without experimental additives. Chickens from the T-5 and T-10 treatments received a hydrocolloid of Ag-NPs at a concentration of 5 mg/l (treatment T-5) or 10 mg/l (treatment T-10) from their second week of life. Blood for analysis was collected at the age of 42 days from 8 birds per treatment. Ceruloplasmin (Cp), leukocyte count (WBC), erythrocyte sedimentation rate (ESR), interleukin IL-6, immunoglobulins IgA, IgY, phagocytic cells (% PC), phagocytic index (PI), nitroblue tetrazolium reduction (NBT), and lysozyme content in the blood was determined. Application of Ag-NPs at a concentration of 5 mg/l or 10 mg/l in the dose range of 2.87-12.25 mg/bird (administration of Ag-NPs in concentration 5 mg/l in weeks: 2; 2 and 3; 2 and 4; 2 and 5; 2 and 6 or concentration 10 mg/l in week 2) resulted in an immunostimulatory effect expressed as an increase in heterophil respiratory burst and an increased concentration of lysozyme. Higher doses of Ag-NPs exerted a pro-inflammatory effect, as indicated by elevated levels of IL-6 and ceruloplasmin, as well as a high ESR. They also stimulated B lymphocytes to produce IgA and IgA immunoglobulins.

In the case of animals characterized by a strongly marked seasonality of reproduction, extremely significant seem to be periodical fluctuations in the concentration of proteinaceous substances identified in tissues and fluids of epididymides, which take part in the maturation process of sperm cells. The aim of the present study was to compare the seasonal expression of identified proteins present in various regions of the mature roe deer (Capreolus capreolus) epididymides, which are regulating the biological functions of spermatozoa and participating in their cytoskeleton organization during the sperm maturation process. Epididymal tissue homogenates and epididymal fluids were analyzed by two-dimensional electrophoresis (2D-PAGE) and tandem mass spectrometry (MS/MS) to reveal 31 polypeptides with different biochemical functions. Moreover, among the identified polypeptides, twelve of them were similar to: alpha-enolase isoform 3; endoplasmic reticulum resident protein 29; calreticulin, calponin-1 isoform X1; transgelin; vimentin; tubulin; desmin; tropomyosin; actin; alpha-1 antitrypsin isoform X1 and 14-3-3 protein epsilon. Concentrations of the analyzed polypeptides, expressed in optical density units (ODU), differed significantly (P≤0.05) across the examined periods of the reproductive season. The highest ODU values of almost all analyzed proteins were observed during the rutting period. This variation in the identified proteins in the epididymal tissues and fluids of roe deer throughout the reproductive season could be indicative of their important roles in sperm maturation within the epididymis.

An effect of the exposure to chloramphenicol (CAP) at doses used therapeutically was studied in pigs at the age of slaughter. Pigs were treated with CAP intramuscularly (20 mg/kg b.w. two times every 24 hours). Histomorphometrical and immunohistochemical analyses of small intestine and liver were done. CAP increased the thickness of myenteron and submucosa, and the length of villi; decreased the depth of crypts in the duodenum and jejunum. CAP influenced the Auerbach plexus. A decrease in cell proliferation, an increase in the number of apoptotic cells and T lymphocytes in the CAP-treated pigs were observed. CAP induces hepatotoxicity, neurotoxicity and disturbed intestinal epithelium. It can be concluded that short exposure of pigs to CAP at doses used therapeutically results in disturbed digestion and absorption process in the intestine.

Glutamine plays an important role in neonatal growth and health. It is unknown whether supplementing the lactating sows’ diet with glutamine will benefit the growth performance and intestinal development of suckling piglets through increasing content of milk glutamine. A total of 24 lactating sows (Large White) were fed diets supplemented with/without 1% glutamine throughout the 21-d lactation. Feed intake of the sows was recorded, blood and milk samples were collected. Piglets were weighed at birth and weaning, one piglet randomly selected from each litter was sacrificed for morphological analysis of the small intestine. Average daily feed intake of the sows did not differ between control and glutamine groups. Concentrations of total protein and urea nitrogen in sows’ serum was increased by glutamine at d 14 of lactation (P<0.05). Contents of glutamine in both plasma and milk of sows were significantly increased by glutamine supplementation throughout lactation (P<0.01). Concentrations of proline, citrulline, valine, isoleucine, leucine, and arginine in sows’ plasma were increased by glutamine supplementation (all P<0.05). Milk yield was increased by glutamine supplementation at d 14 and 21 of lactation (P<0.05). Supplementing the lactating sows’ diet with glutamine increased average daily gain (P=0.006), weaning weight (P=0.032), as well as villous height and ratio of villous height:crypt depth in duodenum of the suckling piglets (both P<0.05). Collectively, supplementing lactating sows’ diet with 1% glutamine significantly improved the growth performance of suckling piglets through elevating milk yield and glutamine content in the milk.

Red osier dogwood (ROD) is an abundant shrub plant in Canada and other places in the world. It is rich in antioxidants such as quercetin, gallic acid and tyrosol. The objective of this study was to evaluate the effects of substituting barley silage with ROD in high-forage (HF) or high-grain (HG) diets on gas production (GP), dry matter (DM) disappearance (DMD) and fermentation characteristics in ruminal batch cultures. The study was a randomized design with 2 media pH (5.8 vs. 6.5) × 4 doses of ROD. An additional treatment of monensin and tylosin was added as a positive control for each pH level. The basic diet consisted of 60% barley silage and 40% barley grain for HF or 15% silage and 85% grain for HG diet. The barley silage was partly replaced with ROD at 0, 3, 6 or 12% in both diets (DM basis). Each diet was incubated for 24 h in culture bottles with three replicates for each treatment combination, and three runs on different days. The GP and DMD were greater (P<0.01) with media pH 6.5 vs. pH 5.8. The DMD linearly (P<0.01) decreased at pH 5.8 with increasing levels of ROD. Increasing ROD levels also linearly (P<0.01) decreased total VFA concentration and the proportion of propionate, and increased (P<0.01) the acetate to propionate ratio (A:P) at pH 5.8. Compared to the antibiotic treatment, the inclusion of ROD resulted in lower (P<0.02) DMD at pH 5.8, and a greater (P<0.01) proportion of acetate but a lower (P<0.01) proportion of propionate. These results indicated that the DMD of diets and the fermentation pattern were adversely affected by ROD at pH 5.8. However, the increased A:P along with the decreased DMD at pH 5.8, suggested a lower impact on fibre digestion than on starch digestion by ROD. Feeding ROD may therefore potentially reduce the incidence of rumen acidosis resulting from feeding HG diets to ruminants by decreasing starch digestion in the rumen.

The objective of this study was to evaluate the impacts of castor meal, a by-product of the biodiesel industry, on growth performance and feeding behavior of heifers in a pasture production system in Northeast Brazil. Forty Holstein × Zebu crossbred heifers with an initial body weight of 257±26 kg were kept on a Brachiaria decumbens pasture under continuous grazing. The experiment lasted 140 days and was conducted in a completly randomized design with five levels of replacement of soybean meal with castor meal (0, 200, 500, 750, and 1000 g/kg of dry matter) in the supplements. Intake, digestibility, feeding behavior, performance, and carcass characteristics were evaluated. The total intakes of dry matter (DM), crude protein (CP), organic matter (OM), ether extract, and total digestible nutrients (TDN) decreased as the castor meal levels were increased. The digestibility coefficients of DM, CP, OM, and TDN decreased as the levels of castor meal in the supplement were increased. The castor meal levels in the supplement did not affect final body weight, average daily gain, feed conversion, hot carcass weight, or carcass dressing of the heifers. The use of supplements containing up to 1000 g/kg DM castor meal replacing soybean meal reduced the DM intake but did not change the average daily gain and feed efficiency of the heifers. Thus, the use of castor meal is a recommendable strategy to reduce production costs in a beef cattle grazing system.

The principal goal of this study was to assess the responses of broiler chickens raised on floor litter to the 2% dietary level of lactose (LAC) originating from dried whey fed in combination with live culture of Lactobacillus agilis bacteria (90 million cells/kg diet) in terms of the performance and basic postslaughter parameters, the lumen pH in some alimentary tract segments, concentration of volatile fatty acids (VFA ) in the total (T) and undissociated (UD) forms and count of selected microbial populations in the caeca determined by fluorescent in-situ hybridisation (FISH). A parallel aim was to evaluate the outcomes from the combined supplementation in comparison with feeding of LAC and the L. agilis bacteria as separate dietary supplements. Six hundred and forty Ross 308 chickens were placed in 16 floor pens (40 birds per pen having equal sex ratio) and were provided with free access to the feed (a mash maize-wheat-soybean meal-based diet) and water. Dietary treatments provided from day 8 to 42 of age were: LAC-free basal diet (CON), LAC-containing diet (CON + LAC), LAC-free diet with the addition of L. agilis (CON + BAC) and LAC-containing diet with addition of L. agilis (CON + LAC + BAC). The LAC supplementation caused significant decreases in the luminal pH of the crop, ileum and caeca, and the addition of the L. agilis bacteria reduced the pH in the crop and caeca. The overall concentration of total (T) volatile fatty acids was higher in the caeca of broilers receiving the LAC-containing diets. Both the LAC and the BAC supplements, independently from one another, resulted in significantly greater caecal levels of UD acetate, propionate and butyrate. The FISH analysis revealed that counts of Bacteroides sp./Prevotella sp. group were higher after the inclusion of LAC in the feed. All three dietary supplementations significantly reduced the total counts of the family Enterobacteriaceae and decreased the number of naturally occurring C. perfringens bacteria compared with the basal control diet (CON). Neither LAC inclusion nor BAC addition to the diet affected the counts of the Clostridium coccoides/Eubacterium rectale group. The synergistic effects of the simultaneous supplementation of LAC and L. agilis were found on the T butyrate concentration and on C. perfringens and the Enterobacteriaceae counts. No improvements in the body weight gains and post-slaughter traits were observed due to uncombined and combined supplementation with 2% LAC and L. agilis, indicating that the shifts in composition of the caecal microbiota toward a healthier composition by using these additives were not large enough to create the positive growth rate and processing yields responses in broilers maintained in a litter-floor environment.

The aim of the present study was to determine the effect of amaranth seeds, dried sea buckthorn pomace and dried chokeberry pomace on the growth performance of broiler chickens and on the fatty acid profile and oxidative stability of meat lipids. The study was conducted on 480 Ross 308 chickens assigned in the second production phase to 4 experimental groups. The birds from the control group received 3% flax oil, while the chickens from the experimental groups were fed with mixtures containing: 3% flax oil and 8% amaranth seeds (group II), 3% flax oil and 3% dried sea buckthorn pomace (group III), and 3% flax oil and 3% dried chokeberry pomace (group IV). Basic production parameters were evaluated for each feeding period. At 42 days of age, 8 birds with body weight close to the average from each group were slaughtered. A simplified analysis of the chicken carcasses was conducted and samples of the breast muscles were collected for further analysis. The addition of 8% amaranth seeds into the feed mixtures in the second feeding phase decreased body weight gains (P<0.05) and increased the feed conversion ratio compared with groups receiving sea buckthorn or chokeberry pomace. However, the addition of amaranth seeds into the feed mixtures increased breast muscle yield (P<0.05) and decreased fat content in comparison to the other experimental groups. Moreover, sensory analysis of the breast muscles from chickens fed the diet with amaranth seeds revealed that they were characterised by a better aroma (P<0.05) and flavour. The studied feed additives did not significantly affect the physicochemical properties of the breast muscles. Sea buckthorn pomace efficiently slowed down lipid oxidation in the breast muscles. The obtained results indicate that using tested plant additives in feed mixture may be an effective way to improved production parameters of broiler chicken and effectively enriched meat in n-3 fatty acid and protect against excessive oxidation of lipids.

The aim of this study was to determine the effect of different dietary levels and sources of methionine (Met) on the growth performance of turkeys, carcass and meat quality. A total of 816 Hybrid Converter turkeys in 6 groups and 8 replications were fed wheat-soybean meal-based diets supplemented with three sources of Met: DL-isomer, L-isomer and DL-hydroxy analog (DLM, LM and MHA, respectively). In four 4-week periods (from 1 to 16 weeks of age), the Met content of turkey diets corresponded to the level recommended by NRC (1994) or was increased by approximately 50% to match the intake recommended by some breeding companies. Increased dietary Met content resulted in a higher final body weight (BW) of turkeys (P=0.002) and a lower feed conversion ratio (FCR) (P=0.049), but had no effect on carcass dressing percentage and most parameters of carcass quality. The higher dietary Met level contributed to a decrease in meat pH, a lower contribution of redness and a smaller muscle fiber diameter (P=0.028, P=0.040 and P=0.004, respectively). The higher dietary Met level had no influence on the redox status of meat, but it reduced the incidence of lymphoid cell infiltration between muscle fibers threefold (P=0.003). Throughout the experiment, no significant differences were noted in the growth performance parameters of turkeys, irrespective of Met source. MHA contributed to higher abdominal fat content, lower dry matter (DM) content and lower catalase (CAT) activity in breast meat, compared with DLM and LM. Increased dietary Met content, approximately 50% higher than that recommended by NRC (1994), regardless of Met source, led to higher final BW of turkeys, but had no effect on carcass dressing percentage and most parameters of carcass quality.

The present study investigated the effect of the type of alternative housing system, and genotype and age of laying hens on physical traits of egg shell and contents. It was demonstrated that alternative housing system type influenced egg weight and shape, and eggshell color and yolk color intensity. Eggs from free-range system were heavier and were characterized by more intense yolk color. No effect of alternative housing system type on albumen height, value of Haugh units (HU value) and presence of meat and blood spots was noted. Hen genotype had a significant effect on egg weight and eggshell color intensity in each of the alternative housing systems tested in this study. Hy-line Brown hens laid heavier eggs than hens of native breeds. Genotype was also observed to affect egg content traits (albumen height, HU values and presence of meat and blood spots). Independently of the type of alternative housing system, most blood and meat spots were noted in eggs of hens laying brown-shelled eggs, i.e. R-11 and Hy-line Brown layers. Laying hen age significantly impacted on egg weight, yolk percentage, eggshell traits (color intensity, weight, thickness and strength) and egg content traits (HU value, yolk weight and color intensity, presence of meat and blood spots). Older hens laid heavier eggs with a greater yolk percentage but with thinner eggshell.

Carcass and meat quality of male and female Anatolian water buffaloes were investigated using 10 carcasses from each gender. Gender had no influence on carcass characteristics, except warm carcass weight, which was 13% higher in males compared to females. Meat from male water buffaloes had higher ultimate pH and lightness (L*), but lower redness (a*) values than females. Meat samples aged for 21 days had lower values for expressed juice, cooking loss and Warner Bratzler shear force compared with those of 7-day aged ones. Meat samples aged for 21 days had higher L* value at 1 h and 24 h after cutting, a* value at 1 h after cutting compared with those of 7-day aged meat samples. Gender had no effect on meat sensory characteristics. Meat from male water buffaloes had higher proportions of C14:0, C18:3 n-3, C20:2 n-6, C20:3 n-3 and C20:4 n-6 and Σn-3 fatty acids and lower Σn-6/Σn-3 ratio compared with female water buffaloes.

The objective of the study was to analyse selected physical properties and chemical indicators of internal organs obtained from fattening pigs and Central European wild boars (Sus scrofa scrofa). Each group consisted of 12 animals. The tongue, heart, lungs, liver and kidneys were examined for physical properties, basic chemical composition, macro- and micromineral content, and fatty acid profile. The atherogenic index (AI) and the thrombogenic index (TI) were also determined. Pig offal was found to be a rich source of protein and collagen, and to contain large amounts of potassium and sodium. Liver had a high content of iron, zinc, and manganese. Pig liver and wild boar heart were characterised by favourable PUFA /SFA ratios (above 0.4%). In addition, the content of neutral and hypocholesterolemic acids (DFA ) and hypercholesterolemic acids (OFA ) in pig offal was comparable to that in pig meat. The results presented in this study provide an extensive evaluation of the nutritional quality of pig offal, which allows an increase in the scope of its use in the food industry, among others for production of offal products, including traditional and regional products that are increasingly demanded by consumers.