Allium-Based Phytobiotic for Laying Hens’ Supplementation: Effects on Productivity, Egg Quality, and Fecal Microbiota

The poultry industry is constantly demanding novel strategies to improve the productivity and health status of hens, prioritizing those based on the holistic use of natural resources. This study aimed to assess the effects of an Allium-based phytobiotic on productivity, egg quality, and fecal microbiota of laying hens. One hundred and ninety-two 14-week-old Lohmann Lite LSL hens were allocated into an experimental farm, fed with a commercial concentrate with and without the Allium-based phytobiotic, and challenged against Salmonella. Productivity, egg quality, and fecal microbiota were monitored for 20 weeks. Results showed that the phytobiotic caused an increase on the number of eggs laid (p < 0.05) and in the feed conversion rate (p < 0.05); meanwhile, egg quality, expressed as egg weight, albumin height, haugh units, egg shell strength, and egg shell thickness remained unchanged (p > 0.05), although yolk color was decreased. Fecal microbiota structure was also modified, indicating a modulation of the gut microbiota by increasing the presence of Firmicutes and Bacteroidetes but reducing Proteobacteria and Actinobacteria phyla. Predicted changes in the functional profiles of fecal microbiota suggest alterations in metabolic activities that could be responsible for the improvement and maintenance of productivity and egg quality when the phytobiotic was supplemented; thus, Allium-based phytobiotic has a major impact on the performance of laying hens associated with a possible gut microbiota modulation.

Effects of Dietary Incorporation of Grape Stalks Untreated and Fungi-Treated in Growing Rabbits: A Preliminary Study

This study aimed to evaluate the effect of the incorporation of untreated grape stalks (UGS) and fungi-treated grape stalks (Lentinula edodes, TGS) in rabbits’ diets. The control group was fed with a control diet without grape stalks (C), two experimental groups were fed on diets with 5% and 10% incorporation of UGS (5UGS and 10UGS), and two with 5% and 10% incorporation of TGS (5TGS and 10TGS). Rabbits fed with TGS diets showed higher daily weight gain (p = 0.034), feed conversion rate (p = 0.002), carcass weight (p = 0.038), and reference carcass weight (p = 0.03) when compared to the control diet. Moreover, animals fed with TGS diets showed an increase in the caecum (p = 0.015) and small intestine (p = 0.021) lengths and in the total volatile fatty acid content (p = 0.005) compared to animals fed UGS diets. Blood triglyceride levels were lower in animals fed with TGS diets compared to UGS (p = 0.005) and C (p ≤ 0.001) diets (12% and 19% lower, respectively), and a trend to lower cholesterol levels was observed (p = 0.071). Meat from rabbits fed with TGS diets had higher levels of linoleic acid, γ-linolenic, ∑ω-6, ∑PUFA, and ∑PUFA/∑SFA ratio compared to rabbits fed with the C diet. Results indicated that grape stalks (UGS and TGS) could be effectively used as an alternative raw material in rabbits’ diets without compromising animal performance.

Effects of Water Temperature on Growth Criteria of Fingerlings of Grass Carp, Ctenopharyngodon idella (Valenciennes, 1884)

The current experiment was conducted in the Fish Laboratory of Aquaculture Unit, College of Agriculture, University of Basrah from 28th January to 19th April 2021. Growth criteria of grass carp Ctenopharyngodon idella were investigated using four water temperatures (15, 20, 25 and 30 oC). Grass carp fingerlings (4.92 g) were brought from earthen ponds of the Aquaculture Unit in Al-Hartha Station for Agricultural Researches, North Basrah. The results indicated that the highest final weight (7.96 g) was reached by fishes at 15 0C, while the lowest final weight (7.22 g) was at 30 0C. Weight increments for fishes were 3.02, 2.97, 2.76 and 2.22 g for water temperatures of 15, 20, 25 and 30 0C, respectively. Fishes had the highest daily growth rate (0.0425 g/day) at 15 0C and the lowest (0.0312 g/day) at 30 0C. Fishes at 20 0C had the best feed conversion rate of 4.03, while fishes at 30 0C had the worst feed conversion rate of 5.29. It can be concluded that the best growth criteria were obtained from fishes at 15 0C and 20 0C, while the worst was observed at 30 0C.

Effects of Three-Layer Encapsulated Tea Tree Oil on Growth Performance, Antioxidant Capacity, and Intestinal Microbiota of Weaned Pigs

Tea tree oil (TTO) exerts key roles in improving growth performance of pigs. However, knowledge is limited regarding comparative effects of Encp TTO and Un-encp TTO supplementation on growth performance of pigs. A study determined the effects of TTO or its capsulation on growth performance, antioxidant capacity, and intestinal microbiome of weaned pigs. A total of 144 healthy pigs (8.5 ± 0.24 kg) were subjected to four treatments for a 28-d trial with six replicates per treatment and six pigs per pen: negative control, NC; positive control, PC (antibiotic supplemented); Un-encp TTO (supplemented with unencapsulated TTO); Encp TTO (supplemented with encapsulated TTO). NC, TTO, and PC treatments were compared with regard to improved average daily gain (ADG), average daily feed intake (ADFI), feed conversion rate, nutrient digestibility, and intestinal morphology (p &lt; 0.05) and decreased diarrhea rate. TTO- and PC-treated pigs had higher levels of serum superoxide dismutase, glutathione peroxidase, and immunoglobulin G; lower levels of liver aspartate aminotransferase and alanine aminotransferase; and improved concentrations of interleukin 10 (IL-10), tumor necrosis factor α, and IL-1β (p &lt; 0.05). TTO- and PC-treated pigs had higher abundance of beneficial bacterial species Subdoligranulum and lower abundance of diarrhea associated species Escherichia–Shigella in cecal and colonic digesta (p &lt; 0.05). Encapsulation of TTO preserved more activities of TTO than its unencapsulated counterpart by showing higher ADG, ADFI, and feed conversion rate during day 1 (d1) to d14 (p &lt; 0.05) and tended to lower diarrhea rate (p = 0.083) and improve villous height/crypt depth (VH/CD) ratio (p = 0.089) in jejunum. Encapsulation of TTO also improved antioxidant indexes and decreased liver injury and inflammation accordingly (p &lt; 0.05). Encapsulated TTO-treated pigs had higher abundance of beneficial Clostridium_sensu_stricto_1 and lower the abundance of harmful Escherichia–Shigella in cecal and colonic digesta (p &lt; 0.05). Our results demonstrated TTO benefits on improving growth performance of weaned pigs and further proved that encapsulation of TTO was superior to its unencapsulated counterpart at multiples. Encapsulated TTO was similar to the PC group and could be potentially an alternative of feed antibiotics for weaned pigs.

Effects of in feed removal of antimicrobials in comparison to other prophylactic alternatives in growing and finishing pigs

ABSTRACT The utilization of antimicrobials in animal production, causes selection of resistant bacteria. The objective of this study was to compare the utilization of alternatives in association with preventive antibiotic therapy in swine feed during the growing and finishing phases. 1,045 animals were used from 60 to 190 days of age and were subjected to six treatments with 16 repetitions as follows: 1) antibiotic free; 2) antibiotics; 3) prebiotic; 4) probiotic; 5) essential oils; and 6) organic acid. Animals were weighted, and clinical history was recorded including mortality and diarrhea. At the abattoir, pneumonia index and gastric ulcers were investigated. The cost for each treatment was discussed. No difference between treatments were observed (P>0.05) regarding feed conversion rate (2.64±0.03), overall average weight gain (107.06±0.9kg), average daily weight gain (856.49±7.7g) and carcass weight (92.4±0.7kg). The application injectable drugs in animals presenting clinical symptoms, represented US$ 0.56/intervention, without difference between the treatments (P>0.05). Furthermore, independently of the treatment, high frequency of pneumonia was observed (>0.90). No difference for the degree of gastric ulcer nor feces consistency were observed (P>0.05). The utilization of antibiotic therapy and alternatives to antibiotics in feed did not produce benefits to the production indices and sanitary performances of the animals.

Effects of Glutathione on Growth, Intestinal Antioxidant Capacity, Histology, Gene Expression, and Microbiota of Juvenile Triploid Oncorhynchus mykiss

This study aimed to demonstrate the effects of dietary glutathione (GSH) on growth, intestinal antioxidant capacity, histology, gene expression, and microbiota in juvenile triploid rainbow trout (Oncorhynchus mykiss). Different diets (G0-control, G100, G200, G400, and G800) containing graded levels of GSH (0, 100, 200, 400, and 800mgkg−1) were fed to triplicate groups of 30 fish (initial mean weight 4.12±0.04g) for 56days. G400 had significantly improved weight gain and feed conversion rate. Based on the broken-line regression analysis, the optimum dietary GSH level was 447.06mgkg−1. Catalase and superoxide dismutase activities were significantly higher in G200–G800. G200 had significantly lower malondialdehyde content. The height of the intestinal muscular layer in G400 was significantly higher than that of the control group. Intestinal PepT1 and SLC1A5 gene expression was significantly increased, and the highest was observed in G400. TNF-α, IL-1β, IL-2, and IL-8 expression were significantly decreased than that of G0. Next-generation sequencing of the 16S rDNA showed a significant difference in alpha diversity whereas no differences in beta diversity. On the genus level, LefSe analysis of indicator OTUs showed Ilumatobacter, Peptoniphilus, Limnobacter, Mizugakiibacter, Chelatococcus, Stella, Filimonas, and Streptosporangium were associated with the treatment diet, whereas Arcobacter, Ferrovibrio, Buchnera, Chitinophaga, Stenotrophobacter, Solimonadaceae, Polycyclovorans, Rhodococcus, Ramlibacter, and Azohydromonas were associated with the control diet. In summary, feeding juvenile triploid O. mykiss 200–800mgkg−1 GSH improved growth and intestinal health.

PSXV-8 The study of feeding behavior traits in connection to feed efficiency in duroc boars bred in Russia

The study of feeding behavior is of particular interest because it is directly related to efficiency of feeding. The aim of our study was to determine the genetic parameters of the feeding behavioral traits in Duroc boars (n = 766) in relation to the feed efficiency based on the analysis of variation components. Genstar and Shauer feeders were used to collect the behavioral data, including daily feed intake (DFI), total daily time spent in feeder (TPD), number of daily visits to feeder (NVD), average duration of each visit (TPV), feed intake per visit (FPV), and feed intake rate (FR). Genetic and environmental variabilities were determined by the mixed model equation using the REMLF90 program. Multiple regression analyses were used to adjust feed conversion rate (FCR) for the duration of the testing period, initial and final body weight, and average daily gain. The average initial body weight was 35.7 kg and the duration of testing period was 78.1 days. Actual FCR values reached 2.20 kg/kg with a phenotypic variability of 26.3%. Moderate values of heritability coefficients (h2) were observed for TPV (h2=0.168), FCR (h2=0.214), and DFI (h2=0.221) traits. The heritability parameters for FPV and TPD traits were higher and accounted to 0.269 and 0.290, respectively. The highest value of h2 was observed for NVD (0.494). Analyses of genetic correlations revealed several interesting findings. The boars, which more often visited feeding stations, spent more time in feeder (r2=+0.536 for NVD/TPD), herewith duration of each visit and feed intake rate were decreased (r2=–0.593 and –0.760 for NVD/TPV and NVD/FR, respectively). Feed conversion rate was positively correlated with TPD (r2=+0.530) and negatively correlated with FR (r2=–0,772). Our research results will be useful for development of artificial selection programs to select Duroc pigs for increased feeding efficiency. The study was supported by RFBR No19-316–90008.

Microbial taxa in dust and excreta associated with the productive performance of commercial meat chicken flocks

Background A major focus of research on the gut microbiota of poultry has been to define signatures of a healthy gut and identify microbiota components that correlate with feed conversion. However, there is a high variation in individual gut microbiota profiles and their association with performance. Population level samples such as dust and pooled excreta could be useful to investigate bacterial signatures associated with productivity at the flock-level. This study was designed to investigate the bacterial signatures of high and low-performing commercial meat chicken farms in dust and pooled excreta samples. Poultry house dust and fresh pooled excreta were collected at days 7, 14, 21, 28 and 35 of age from 8 farms of two Australian integrator companies and 389 samples assessed by 16S ribosomal RNA gene amplicon sequencing. The farms were ranked as low (n = 4) or high performers (n = 4) based on feed conversion rate corrected by body weight. Results Permutational analysis of variance based on Bray–Curtis dissimilarities using abundance data for bacterial community structure results showed that company explained the highest variation in the bacterial community structure in excreta (R2 = 0.21, p = 0.001) while age explained the highest variation in the bacterial community structure in dust (R2 = 0.13, p = 0.001). Farm performance explained the least variation in the bacterial community structure in both dust (R2 = 0.03, p = 0.001) and excreta (R2 = 0.01, p = 0.001) samples. However, specific bacterial taxa were found to be associated with high and low performance in both dust and excreta. The bacteria taxa associated with high-performing farms in dust or excreta found in this study were Enterococcus and Candidatus Arthromitus whereas bacterial taxa associated with low-performing farms included Nocardia, Lapillococcus, Brachybacterium, Ruania, Dietzia, Brevibacterium, Jeotgalicoccus, Corynebacterium and Aerococcus. Conclusions Dust and excreta could be useful for investigating bacterial signatures associated with high and low performance in commercial poultry farms. Further studies on a larger number of farms are needed to determine if the bacterial signatures found in this study are reproducible.

Effect of density and mixed culture of largemouth bass (Micropterus salmoides) and pikeperch (Sander lucioperca) on growth, survival and feed conversion rate in intensive culture

In this study, two experiments were performed with the aim to optimize intensive aquaculture of largemouth bass (Micropterus salmoides). In the first 140-day experiment the effect of the initial fish density was assessed at three levels: low density (LD) 23 kg/m³, medium density (MD) 35 kg/m³ and high density (HD) 46 kg/m³. All three densities provided the same final Fulton’s condition coefficient (FC = 1.24–1.28), specific growth rate (SGR = 0.22–0.24%/day) and survival rate (97–100%). No cannibalism was observed at all tested densities. Feed conversion ratio (FCR = 1.39 ± 0.21 g/g) was the lowest for LD and the highest (1.61 ± 0.08 g/g) for MD. The highest fish biomass (25.7 ± 2.7 kg/m³) was obtained at HD and this density was considered as the most effective density of all tested ones during the intensive culture of largemouth bass. The second 60-day experiment tested the effect of largemouth bass and pikeperch (Sander lucioperca) monoculture and biculture of both species on production efficiency. Higher size heterogeneity was obtained in both (mono- and bicultural) groups of pikeperch (308.91–314.56‰/day) compared to the groups of largemouth bass (279.26–284.05 ‰/day). The higher FC (1.09) was found in both types of culture in largemouth bass compared to both methods of culture in pikeperch (0.74–0.78). The lowest SGR was evident in both types of largemouth bass cultures (1.20–1.28%/day). In contrast, the highest SGR was achieved in the bicultural pikeperch (1.88%/day). Similar results like for SGR were also assessed for FCR, where the highest value of FCR was in both cultures of largemouth bass (1.44–1.48 g/g) compared to the lowest FCR in the bicultural of pikeperch (0.73 g/g). Largemouth bass in both tested types of culture had higher survival rates (99.95–99.99%) compared to pikeperch (98.61–98.63%).

The role of dietary supplements in the meat productivity of rabbits with a dry type of feeding

The role of vitamin-mineral premix and nanocrystalline iron in the meat productivity of young rabbits was studied by classical methods in the scientific and economic experience in the departments of fur farming and Rabbit Breeding of the V. A. Afanasyev Research Institute of Fur Farming and Rabbit Breeding. From 180 heads of young rabbits at the age of 45 days, 3 groups of 60 heads each were formed according to the principle of analogues: the 1-st-control group received a typical full-fledged granulated mixed feed (FGMF) with a vitamin-mineral premix P 90-2T, in the (FGMF) of the 2-nd and 3-rd experimental groups, the premix was absent, but nanocrystalline iron was included in the (FGMF) of the 3-rd group. Control slaughter of rabbits to assess meat productivity was carried out at the age of 90 days. During the experiment, it was found that the feed in all groups was identical in gross caloric content, but slightly different in the ratio of nutrients. In the mixed feed of the experimental groups, there were more nutrients with the highest digestibility coefficient (fat and soluble carbohydrates) and almost 2 times less fiber, which is slightly digested in young rabbits, only by 3-10%. Rabbits of all groups had no significant differences in live weight and average daily gain. But during the fattening period, the rabbits of the experimental groups consumed less feed when feeding freely than in the control group. At the same time, there were no significant differences in the mass of the carcass and the slaughter yield between the groups. But the feed conversion rate in the experimental groups was 1.32 and 1.28 lower than in the control group, which is economically advantageous. Based on the results of the experiment, it can be assumed that the inclusion of biologically active additives in the form of vitamin-mineral premix and nanocrystalline iron in the full-fledged granular feed for young rabbits does not make much sense, since it does not contribute to increasing meat productivity. In the cost of mixed feed, the vitamin and mineral premix accounts for 10%. Optimizing the ratio of nutrients in the diet plays a crucial role in reducing the feed conversion rate.