Impacts of Age, Genotype and Feeding Low-Protein Diets on the N-Balance Parameters of Fattening Pigs

The effects of feeding low-protein (LP) diets and the age and genotype of fattening pigs were evaluated in an N-balance trial. Sixty weaned piglets of two genotypes were allotted to three different diets. Besides the control diets for the crossbred Topigs 20 × DanBred Duroc (TD) and Hungarian Large White (HLW) pigs, two LP diets were fed containing 1.5 (T1.5) and 3% (T3) less dietary protein than the control. The LP diets were supplemented with crystalline lysine, threonine, tryptophan, and methionine to equalize their digestible amino acid contents. Starter diets were fed between 20–30, grower I between 30–40, grower II between 40–80 and finisher between 80–110 kg live weights. Pigs were kept in floor pens, with 10 animals per pen. In all phases, six pigs with similar live weight were placed into individual balance cages and in the frame of a seven-day long balance trial, the daily N-intake, fecal and urinary N-excretion were measured. From the data N-digestibility, the total ammoniacal nitrogen (TAN) and N-retention were calculated. All the investigated main factors, the genotype and age of pigs and the protein content of the diets had significant effects on the N-balance of fattening pigs. The determinacy of the factors depended on the investigated parameter. Fecal N-excretion and N-digestibility were steadier compared with the urinary N-exertion and TAN percentage. N-digestibility increased and the urinary N-excretion decreased when LP diets were fed. The urinary N-decreasing effect of LP diets was not linear. Compared with the control (19.6 gN/day), T1.5 treatment resulted in 14.5, treatment T3 in 12.4 g daily urinary N-excretion. The TAN and the N-retention of HLW pigs were more favorable than those of TD pigs. Based on our results, it can be concluded that the accuracy of the nitrogen and TAN excretion values of pigs, used in the calculation of the national NH3 inventories, could be improved if the genotype, the more detailed age categories and the different protein levels of feeds are considered.

Changes of Androstenone Concentrations in Saliva of Boars with Age

With the increasing age of boars, the possibility of androstenone (5α-androst-16-en-3-one (AND), 5α-androst-16-en-3α-ol (α-AND), and 5α-androst-16-en-3β-ol (β-AND)) occurrence increases as well. The aim of this study was to evaluate concentrations of androstenone compounds in the saliva of boars concerning the age of animals. In total, 72 boars were evaluated (24 boars per replication). The effect of age (three different ages—152, 163, and 172 days) was observed, and (Landrace × Large White) × Pietrain genotypes were used. Chemical analysis of saliva samples was conducted by multidimensional gas chromatography/mass spectrometry (MDGC/MS). Salivary α-AND increased with age (p < 0.05), and positive correlations were found between age and submaxillary salivary gland weight (p < 0.05), age, and salivary AND concentration (p < 0.05), body weight and submaxillary salivary gland weight (p < 0.05), submaxillary salivary gland weight and salivary β-AND concentration (p < 0.05), as well as submaxillary salivary gland weight and total salivary 5α-androstenone (AND total) concentration (p < 0.001). Nowadays, animal welfare is becoming a more and more discussed topic, and pig breeding is not an exception. Specifically, the castration ban is a current issue, so it is very important to know as much as possible about compounds responsible for boar taint. Androstenone’s appearance in boars’ saliva could be one of the most important precursors for future early detection of boar taint.

Assessment of the drinker type on water intake and toy type on behaviour of nursery piglets

This study was conducted to assess the effect of two types of drinkers on water intake (WI) and two types of toys on behavioural observations of piglets in the nursery phase. A total of 72 crossbred entire male piglets (Landrace × Large White, Agroceres♂ and DanBred♀), weaned at 21 days of age, with an average initial body weight (AIBW) of 6.75 ± 0.19 kg were used. Two statistical models were fitted for WI. In model I, animals were distributed in a completely randomized design (CRD) with a split-plot in time, composed of six treatments (2 types of drinkers × 3 experimental phases), eight replications (days of sampling), and 36 animals/experimental unit (EU), without using AIBW as a covariate. In model II, animals were distributed in a CRD with two treatments (fixed or pendular nipple drinkers), eight replications (days of sampling) and 36 animals/EU, with use of AIBW as a covariate. For assessment of behavioural observations, the model was adjusted in a randomized block design, consisting of four treatments [two types of toys (metal chain and plastic bottle) × two daytime periods (morning and afternoon)], nine replications and three blocks constituted in time (days), totalling four pigs/EU. The results indicated an effect on animal daily WI in the starter phase in model I (p < 0.000) and II (p = 0.006). There was an effect (p ≤ 0.05) of toy type for behavioural observations, in which pigs showed a greater proportion of fighting and belly nosing when they had the bottle toy. However, animals spent more time (p ≤ 0.05) eating, drinking water, overlapping, and playing with the toy when they had access to the chain toy. There was an increase (p ≤ 0.05) in sleeping behaviour in the morning period, as well as greater (p ≤ 0.05) behavioural activity in the afternoon period. In conclusion, WI of nursery piglets was positively influenced by growth phase, and the fixed drinker stimulated greater WI in piglets in the starter phase. In addition, the metal chain, as an environmental enrichment, promoted improvements in feeding behaviour and WI, reducing fighting events, and the afternoon period had increased behavioural observations overall.

Decreasing the level of hemicelluloses in sow's lactation diet affects the milk composition and post-weaning performance of low birthweight piglets.

Hemicelluloses (HC) are polysaccharides constituents of the cell walls of plants. They are fermented in the gut to produce volatile fatty acids (VFA). The present study investigated the effects of decreasing HC level in sow's lactation diet on sow performances, offspring development and milk composition. From 110 days (d) of gestation until weaning (26±0.4 d post-farrowing), 40 Swiss Large White sows were assigned to one of the four dietary treatments: (1) T12 (HC: 120.6 g/kg), (2) T11 (HC: 107.6 g/kg), (3) T9 (HC: 86.4g/kg) and (4) T7 (HC: 71.9 g/kg). Milk was collected at 3 and 17d of lactation. At birth, piglets were divided into two groups according to their birthweight (BtW): normal (N-BtW; BtW > 1.20 kg) or low (L-BtW; BtW ≤ 1.20 kg). Decreased HC levels in the maternal diet linearly increased (P ≤ 0.05) the body weight of L-BtW piglets at two weeks post-weaning and linearly decreased (P ≤ 0.05) diarrhoea incidence and duration in this category. The concentrations of copper, threonine and VFA, as well as the proportion of butyrate, in milk linearly increased (P ≤ 0.05), whereas lactose content linearly decreased (P ≤ 0.05) with decreased HC in the maternal diet. The present study provides evidence that decreasing HC level in sow's lactation diet can positively affect the composition and VFA profile of milk and ultimately favour the growth and health of L-BtW piglets.

Some economically useful signs of the pigs of a Large White breed in OOO “Rossyia”

The researches were carried out in ООО “Rossyia” of the Mozhginsky district of the Udmurt Republic. The object of the research was the sows of the main herd of a Large White pig breed. The reproductive qualities of the sows were studied according to such indicators as: the multiple births, the milkness, the mass of a nest in 2 months. The study of reproductive qualities was carried out using breeding cards of the sows and a book for registering farrowing and offspring of the pigs. The evaluation of the reproductive qualities of sows was carried out by calculating the indicators of a variational statistics: the arithmetic mean, the mean quadrate deviation, the coefficients of the variation, the heritability, the correlation. The indicator of a variational statistics was calculated according to the method of N.A. Plokhinsky. The reliability of the coefficients of the heritability and the correlation was determined using Student's t-test. Then studying the reproductive qualities of the sows of the main herd it was established that the multiple births in the average was 10.61 heads, the milkness — 51.34 kg, and the mass of a nest in 2 months — 156.72 kg. Hereat the coefficient of the variability on the multiple births was 12.95%, on the milkness — 8.41%, and on the mass of a nest in 2 months — 10.02%. The coefficient of heritability on the multiple births was 15.00%, on the milkness — 20.00%, and on the mass of a nest in 2 months — 25.00% (P > 0.999). The coefficients of the correlation between the multiple births and the milkness and the multiple births and the mass of a nest in 2 months, respectively, were r = +0.769 and r = + 0.474, and the coefficient of the correlation between the milkness and the mass of a nest in 2 months — r = + 0.754 under the probability of the infallible prognoses P > 0.999.

First fully endoscopic metabolic procedure with NOTES gastrojejunostomy, controlled bypass length and duodenal exclusion: a 9-month porcine study

We conducted a pilot study of a potential endoscopic alternative to bariatric surgery. We developed a Natural Orifice Transluminal Endoscopic Surgery (NOTES) gastric bypass with controlled bypass limb length using four new devices including a dedicated lumen-apposing metal stent (GJ-LAMS) and pyloric duodenal exclusion device (DED). We evaluated procedural technical success, weight change from baseline, and adverse events in growing Landrace/Large-White pigs through 38 weeks after GJ-LAMS placement. Six pigs (age 2.5 months, mean baseline weight 26.1 ± 2.7 kg) had initial GJ-LAMS placement with controlled bypass limb length, followed by DED placement at 2 weeks. Technical success was 100%. GJ-LAMS migrated in 3 of 6, and DED migrated in 3 of 5 surviving pigs after mucosal abrasion. One pig died by Day 94. At 38 weeks, necropsy showed 100–240 cm limb length except for one at 760 cm. Weight gain was significantly lower in the pigs that underwent endoscopic bypass procedures compared to expected weight for age. This first survival study of a fully endoscopic controlled bypass length gastrojejunostomy with duodenal exclusion in a growing porcine model showed high technical success but significant adverse events. Future studies will include procedural and device optimizations and comparison to a control group.

Exploring the role of gut microbiota in host feeding behavior among breeds in swine

Background The interplay between the gut microbiota and feeding behavior has consequences for host metabolism and health. The present study aimed to explore gut microbiota overall influence on feeding behavior traits and to identify specific microbes associated with the traits in three commercial swine breeds at three growth stages. Feeding behavior measures were obtained from 651 pigs of three breeds (Duroc, Landrace, and Large White) from an average 73 to 163 days of age. Seven feeding behavior traits covered the information of feed intake, feeder occupation time, feeding rate, and the number of visits to the feeder. Rectal swabs were collected from each pig at 73 ± 3, 123 ± 4, and 158 ± 4 days of age. DNA was extracted and subjected to 16 S rRNA gene sequencing. Results Differences in feeding behavior traits among breeds during each period were found. The proportion of phenotypic variances of feeding behavior explained by the gut microbial composition was small to moderate (ranged from 0.09 to 0.31). A total of 21, 10, and 35 amplicon sequence variants were found to be significantly (q-value < 0.05) associated with feeding behavior traits for Duroc, Landrace, and Large White across the three sampling time points. The identified amplicon sequence variants were annotated to five phyla, with Firmicutes being the most abundant. Those amplicon sequence variants were assigned to 28 genera, mainly including Christensenellaceae_R-7_group, Ruminococcaceae_UCG-004, Dorea, Ruminococcaceae_UCG-014, and Marvinbryantia. Conclusions This study demonstrated the importance of the gut microbial composition in interacting with the host feeding behavior and identified multiple archaea and bacteria associated with feeding behavior measures in pigs from either Duroc, Landrace, or Large White breeds at three growth stages. Our study provides insight into the interaction between gut microbiota and feeding behavior and highlights the genetic background and age effects in swine microbial studies.

Evaluation of the phenotypic and genomic background of variability based on litter size of Large White pigs

Background The genetic background of trait variability has captured the interest of ecologists and animal breeders because the genes that control it could be involved in buffering various environmental effects. Phenotypic variability of a given trait can be assessed by studying the heterogeneity of the residual variance, and the quantitative trait loci (QTL) that are involved in the control of this variability are described as variance QTL (vQTL). This study focuses on litter size (total number born, TNB) and its variability in a Large White pig population. The variability of TNB was evaluated either using a simple method, i.e. analysis of the log-transformed variance of residuals (LnVar), or the more complex double hierarchical generalized linear model (DHGLM). We also performed a single-SNP (single nucleotide polymorphism) genome-wide association study (GWAS). To our knowledge, this is only the second study that reports vQTL for litter size in pigs and the first one that shows GWAS results when using two methods to evaluate variability of TNB: LnVar and DHGLM. Results Based on LnVar, three candidate vQTL regions were detected, on Sus scrofa chromosomes (SSC) 1, 7, and 18, which comprised 18 SNPs. Based on the DHGLM, three candidate vQTL regions were detected, i.e. two on SSC7 and one on SSC11, which comprised 32 SNPs. Only one candidate vQTL region overlapped between the two methods, on SSC7, which also contained the most significant SNP. Within this vQTL region, two candidate genes were identified, ADGRF1, which is involved in neurodevelopment of the brain, and ADGRF5, which is involved in the function of the respiratory system and in vascularization. The correlation between estimated breeding values based on the two methods was 0.86. Three-fold cross-validation indicated that DHGLM yielded EBV that were much more accurate and had better prediction of missing observations than LnVar. Conclusions The results indicated that the LnVar and DHGLM methods resulted in genetically different traits. Based on their validation, we recommend the use of DHGLM over the simpler method of log-transformed variance of residuals. These conclusions can be useful for future studies on the evaluation of the variability of any trait in any species.

Genetic diversity of the Central European wild boar (Sus scrofa scrofa) population and domestic pig (Sus scrofa domesticus) breeds based on a microsatellite DNA locus

The results of studies of the genetic structure of the Central European wild boar (Sus scrofa scrofa) population and four breeds of domestic pigs (Duroc, Yorkshire, Large White and Landrace) bred in the Central Black Earth region of Russia are presented in this work. Based on 12 microsatellite loci, a significant ( p <0.05) decrease in the level of genetic variability in bred breeds was shown. The expected heterozygosity and Shannon index were as follows: in the wild boar, Ho = 0.763 ± 0.026, I = 1.717 ± 0.091; in the Duroc breed, Ho = 0.569 ± 0.068, I = 1.191 ± 0.157; in the Landrace, Ho = 0.618 ± 0.062, I = 1.201 ± 0.147; in the Large White, Ho = 0.680 ± 0.029, I = 1.362 ± 0.074; and in the Yorkshire, Ho = 0.642 ± 0.065, I = 1.287 ± 0.156. The results of checking genotypic Hardy–Weinberg equilibrium based on the G-test of maximum likelihood demonstrated that the overwhelming majority of loci in the wild boar population were in the state of said equilibrium. By contrast, in pig breed populations, some loci demonstrated a significant deviation from the indicated equilibrium. In addition, the Yorkshire, Large White, and Landrace populations had loci, for which the hypothesis of neutrality was reliably rejected based on the results of the Ewens–Watterson test. The revealed private alleles, characteristic of the wild boar and breeds, can later be used to identify them. The ordination of the centroids of different herds in the space of the first two principal coordinates based on the matrix of pairwise estimates of Nei’s genetic distances showed that the most distant populations are the Duroc and Boar breeds, and the most genetically close are the Yorkshire and Landrace breeds. The closest to the wild boar population was the Large White breed. The assessment of the effective size, carried out using the method based on the linkage disequilibrium and the molecular coancestry method, showed that in all studied groups, including the wild boar population, the effective size was less than 100 individuals. The low effective size of the wild boar population (Ne = 21.8, Neb = 4.0) is probably caused by the death and shooting of animals due to Pestis africana suum.