Piglet Production Research Articles

Challenges and opportunities of smallholder pig production systems in Rwanda.

To decipher the dynamics, challenges, and opportunities of smallholder pig farming in Rwanda, a household survey was conducted in ten districts of the country. A total of 900 households selected randomly across four provinces and one city, 12 districts, 28 sectors, and villages were interviewed using a pretested printed questionnaire. Most of the respondents were heads of household: 70.9% for western, 63.5% in eastern, 54.1% in northern, and 52.5% in southern province, and their mean age was 46.7years and had widely varying education levels. Crossbred pig genotypes were the most preferred due to their high growth rate and produce large litters compared to local pigs, as well as their high resistance to disease, and can better utilize low-quality feeds compared to pure exotic pigs. Piglets and sows were the biggest populations on most farms. Production of piglets for sale was the main purpose of rearing pigs in 63.7% of the farms. Natural mating was almost (99.1%) exclusive on all farms, implying that artificial insemination is yet to take root in Rwanda. Weeds were reported to be the main feed resource used particularly in wet season, while cereal grain mashes and concentrates were used by very few farmers due to high costs. Dominant challenges related to limited pig and pork markets, high taxation, limited extension services, and disease outbreak were highlighted. The most common diseases affecting pigs were swine erysipelas and internal parasites. Access to veterinary services by the households was limited especially in northern province (20%) leading to wrong diagnosis. Capacity building and provision of access to quality animal health services as well as setting up of markets were proposed as strategies to improve pig production by smallholders in Rwanda and grab a share of the lucrative pork market in the region.

Comparative analysis of technical efficiency of piglet farming in three production center provinces in Indonesia

Pork production occupies the third position in Indonesia, after chicken and beef. Even pigs occupy the top rank in contributing to Indonesia's live animal exports. The purpose of this study was to com-pare the level of technical efficiency of smallholder piglet production farming in three centers of pig production areas, namely North Sumatra, Bali, and East Nusa Tenggara (NTT). The research data was sourced from secondary data at the farm level, collected by the Central Statistics Agency of Indonesia, through the Livestock Business Household Survey. This research utilized the stochastic production frontier model to assess the production efficiency and the one-step maximum likelihood estimation (MLE) method to measure the level of technical efficiency and the significance of the factors. The re-sults show that the average level of technical efficiency of piglet production farms in Indonesia is rela-tively low. Piglet production farms in Bali have the highest efficiency level and NTT is the lowest of the three provinces being compared. The number of pigs, feed expenditure, capital, and vaccinations are important factors in influencing production and the level of technical efficiency. Public policies that can increase farmers' access to production factors and better pig farm vaccine management become a necessity.

Epidemiological Study on Salmonella Prevalence in Sow Herds Using Direct and Indirect Detection Methods.

In piglet production, the beginning of pork production, Salmonella prevalence requires greater attention as having an impact on the subsequent production steps. The aim of this study was to investigate Salmonella prevalence in three sow herds with attached piglet rearing units. Salmonella prevalence was investigated either directly by boot swabs and feces or indirectly by serum samples taken during gilt integration, the peripartal period, and piglet rearing. Boot swabs and feces were analyzed by real-time PCR and subsequent microbiology. Results indicated that high biosecurity measures in sow husbandry do not necessarily result in a low Salmonella prevalence. Furthermore, the sow herds’ Salmonella prevalence should not be used to infer the situation in the associated piglet rearing. The proportion of positive boot swabs was 10.5, 3.6, and 21.3% for sows (gilts and peripartal) with an inverse situation in piglet rearing with 50.0, 63.3, and 5.8% positive swabs for farms A, B, and C, respectively. Boot swabs are suitable as a direct sampling method to gain an overview of Salmonella prevalence in both sows and piglets. Indirect serum antibody testing can be useful, although it should be evaluated considering age-dependent levels of antibody titres.

LncRNA ALDB-898 modulates intestinal epithelial cell damage caused by Clostridium perfringens type C in piglet by regulating ssc-miR-122–5p/OCLN signaling

Diarrhea of piglets caused by Clostridium perfringens type C (C. perfringens type C) infection is a global problem afflicting piglet production. Long noncoding RNA (LncRNA) and microRNA (miRNA) have emerged as critical regulators of this pathological process, but the underlying molecular mechanisms remain unclear. In this study, we first observed the expression changes of ALDBSSCG0000000898 (ALDB-898) and ssc-miR-122–5p in infected ileum tissue of piglets with C. perfringens type C, and then used C. perfringens beta2 toxin (CPB2) to induce intestinal porcine epithelial cells (IPEC-J2) to construct an injury model. Cytometry kit 8 (CCK-8), lactate dehydrogenase (LDH), real-time quantitative polymerase chain reaction (RT-qPCR), Western blot, flow cytometry and fluorescein isothiocyanate-dextran 4 (FITC-Dextran 4) flux assays were performed to study the effect of ALDB-898 and ssc-miR-122–5p in apoptosis, inflammation and intestinal barrier damage and inflammatory in IPEC-J2 cells induced by CPB2. In addition, dual-luciferase reporter gene analysis was performed to confirm the relationship between ssc-miR-122–5p and ALDB-898 or ssc-miR-122–5p and occludin (OCLN), respectively. There were lower expression levels of ALDB-898 and OCLN and higher expression levels of ssc-miR-122–5p in diarrhea piglets caused by Clostridium perfringens type C. ALDB-898 and OCLN were significantly decreased and ssc-miR-122–5p was increased in IPEC-J2 after exposure to the CPB2 in a dose- and time-dependent manner. ALDB-898 overexpression mitigated CPB2-induced cell injury by promoting viability, restraining apoptosis, cytotoxicity, and inflammatory response, as well as weakening the destruction of the intestinal barrier. Further mechanisms disclosed that ALDB-898 functioned as a competing endogenous RNA (ceRNA) via binding to ssc-miR-122–5p, and OCLN was a target of ssc-miR-122–5p. Importantly, the ssc-miR-122–5p mimic led to abolishing the protective function of ALDB-898 on CPB2-induced IPEC-J2 cell damage, and the addition of OCLN reversed the negative impact of ssc-miR-122–5p, thereby restoring the protection of ALDB-898. Our data showed that ALDB-898 could enhance the expression of OCLN through competitive binding ssc-miR-122–5p to suppress CPB2-induced damage. The ALDB-898/ssc-miR-122–5p/OCLN signaling may be a candidate therapeutic pathway for diarrhea of piglets.

Tauroursodeoxycholic acid (TUDCA) improves intestinal barrier function associated with TGR5-MLCK pathway and the alteration of serum metabolites and gut bacteria in weaned piglets

BackgroundTauroursodeoxycholic acid (TUDCA), a hydrophilic bile acid, is the main medicinal component of bear bile and is commonly used to treat a variety of hepatobiliary diseases. Meanwhile, TUDCA has been shown to modulate the intestinal barrier function and alleviate DSS-induced colitis in mice. However, the effect of TUDCA on the intestinal barrier of weaned piglets remains largely unclear.MethodsThe weaned piglets and porcine IPEC-J2 intestinal epithelial cells were used to investigate the effects of TUDCA on intestinal barrier function in weaned piglets and explore the possible underlying mechanisms. In vivo, 72 healthy weaned piglets were randomly allocated into 2 groups according to their gender and body weight, and piglets were fed the basal diet with 0 (control, CON) and 200 mg/kg TUDCA for 30 d, respectively. Three female and three male piglets reflecting the average bodyweight were slaughtered in each group and samples were collected. In vitro, IPEC-J2 cells were subjected to 100 μmol/L TUDCA to explore the possible underlying mechanisms.ResultsOur results demonstrated that dietary TUDCA supplementation significantly reduced the diarrhea incidence of weaned piglets, possibly attributing to the TUDCA-enhanced intestinal barrier function and immunity. In addition, TUDCA supplementation altered serum metabolites and the relative abundance of certain gut bacteria, which might contribute to the improved intestinal barrier function. Furthermore, the in-vitro results showed that TUDCA improved the E. coli-induced epithelial barrier impairment of IPEC-J2 cells and increased Takeda G-coupled protein receptor 5 (TGR5) protein expression. However, knockdown of TGR5 and inhibition of myosin light chain kinase (MLCK) pathway abolished the TUDCA-improved epithelial barrier impairment in E. coli-treated IPEC-J2 cells, indicating the involvement of TGR5-MLCK in this process.ConclusionsThese findings showed that TUDCA improved intestinal barrier function associated with TGR5-MLCK pathway and the alteration of serum metabolites and gut bacteria in weaned piglets, suggesting the potential application of TUDCA in improving gut health in piglet production.

CRISPR/Cas9-Mediated Knockout of the Dicer and Ago2 Genes in BHK-21 Cell Promoted Seneca Virus A Replication and Enhanced Autophagy.

RNA interference (RNAi) is a major form of antiviral defense in host cells, and Ago2 and Dicer are the major proteins of RNAi. The Senecavirus A (SVA) is a reemerging virus, resulting in vesicular lesions in sows and a sharp decline in neonatal piglet production. In this study, CRISPR/Cas9 technology was used to knock out Ago2 and Dicer genes in BHK-21 cell lines used for SVA vaccine production. Cell clones with homozygous frameshift mutations of Ago2 and Dicer genes were successfully identified. The two knockout cell lines were named BHK-DicerΔ- and BHK-Ago2Δ-. Results showed that the two genes’ knockout cell lines were capable of stable passage and the cell growth rate did not change significantly. The replication rate and virus titers of SVA were significantly increased in knockout cell lines, indicating that RNAi could inhibit SVA replication. In addition, compared with normal cells, autophagy was significantly enhanced after SVA-infected knockout cell lines, while there was no significant difference in autophagy between the knockout and normal cell lines without SVA. The results confirmed that SVA could enhance the autophagy in knockout cells and promote viral replication. The two knockout cell lines can obtain viruses with high viral titers and have good application prospects in the production of SVA vaccine. At the same time, the RNAi knockout cell lines provide convenience for further studies on RNAi and SVA resistance to RNAi, and it lays a foundation for further study of SVA infection characteristics and screening of new therapeutic drugs and drug targets.

PSVI-3 Effect of Live Yeast Supplementation on Redox Potential, Gastrointestinal Microbiota, and Short-Chain Fatty Acids in Piglets

Abstract The post-weaning period is a stressful process for piglets with compromised gut health, increasing susceptibility to diarrhea and infection. Oxygen concentration in the gut affects microbiome and fermentation profile. Live yeasts have been used to promote gut health and performance of young animals. An experiment was carried out to determine the influence of live yeast on gut conditions including redox potential, microbial composition, and short chain fatty acid (SCFA) production of piglets. Sixteen Pietrain *(Landrace*Large White) piglets were distributed into blocks by live weight and allocated at 4 per pen for a 28-d trial. Each block was composed by a combination of the 2 dietary treatments corresponding to a control diet and a diet supplemented with live yeast (1 kg/tonne Vistacell, AB Vista). At the end of trial, piglets were euthanized to measure kinetics of redox potential (Eh) and pH from caecum until 35 min post-mortem. Then, digesta samples from stomach, duodenum, jejunum, ileum, caecum, and rectum were collected for microbial composition and SCFA production. Data were analyzed using GLM procedure of SAS 9.4 and means compared with a Student-Newman-Keuls test. Redox potential decreased with time (P < 0.001) until stabilizing after 20 min, and a clear difference was observed between treatments (P < 0.001). Supplemented live yeast survives throughout gastrointestinal tract and modifies microbial populations enhancing lactic acid bacteria (P < 0.001) while reducing enterobacteria (P < 0.001) or eliminating fungi (P < 0.001). The production of SCFA from caecum digesta was 3-fold higher than in ileum with significantly different molar proportion of individual SCFA. Lactic, formic, and acetic acids predominate on ileum (> 93%) whereas acetic, propionic, and butyric dominate on caecum digesta (> 90%). Nevertheless, no differences were observed due to dietary treatments. In conclusion, live yeast supplementation of diets modifies redox conditions prevailing in the gut modifying microbial populations and helping piglets to overcome post-weaning growth check.

Production of Agu piglets after transfer of embryos produced in vitro.

The present study was conducted to examine the feasibility of in vitro embryo production and transfer technologies for producing piglets of Agu, an Okinawan indigenous pig breed. After collection of oocytes from surgically dissected ovaries, they were subjected to in vitro maturation. After in vitro maturation/fertilization, a total of 616 putative embryos were transferred into four commercial Western pig recipients, one of which became pregnant and farrowed a total of eight Agu piglets. These results demonstrate that in vitro embryo production using ovaries from Agu females is useful for breeding management and conservation of indigenous breeds.

Nutritional evaluation of fish protein hydrolysate and its application in piglet production.

This study was conducted to determine the digestible energy (DE), metabolizable energy (ME), and ileal digestibility of amino acids (AA) of fish protein hydrolysate (FPH), and to evaluate the effects of FPH on the performance of piglets. In Exp. 1, the available energy content of FPH was determined by difference methods: 12 barrows with an initial body weight (BW) of 40.0±2.1kg were randomly assigned into two dietary treatments with six replicates per treatment, the treatments contained a corn basal diet and an experimental diet in which 20% corn was replaced by FPH. The experiment lasted for 12 d, with 7 d adaptation period followed by 5 d total collection of feces and urine. In Exp. 2, the standardized ileal digestibility (SID) of AA in FPH by the N-free method was determined, 12 barrows (initial BW of 35.3±1.8kg) with ileal T-cannulas were randomly allotted into two treatments with six replicates per treatment, and the dietary treatments consisted of an experimental diet and a N-free diet. The experiment was lasted for 7 d, with 5 d adaptation period followed by 2 d collection of ileal digesta. In Exp. 3, the effect of FPH on the performance of piglets was conducted. One hundred ninety-two piglets (initial BW of 8.10±1.8kg) were randomly allotted into four treatments with six replicates per treatment. The treatments were a control diet with fish meal (FM) and part or all FM was replaced by FPH, receiving diets containing 2%, 3%, or 5% FPH. The experiment lasted for 28 d. Results showed that in Exp. 1, the DE and ME of FPH were 21.12 and 20.28 MJ/kg. In Exp. 2, the SID of Lys, Met, Thr, and Trp was 79.99%, 87.17%, 68.29%, and 71.53%, respectively. In Exp. 3, addition of 3% FPH increased nutrient digestibility and volatile fatty acid content in feces. Addition of 5% FPH increased the average daily feed intake (ADFI), significantly increased (P < 0.05) the activities of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and immunoglobulin A (IgA), while significantly decreased (P<0.05) the average daily gain (ADG). In conclusion, FPH had a high value of digestible energy and ileal digestible essential amino acids, and could improve nutrient digestibility, immunity, antioxidant capacity, and intestinal health of piglets, while adverse to nitrogen deposition in piglets.

Combined Effect of Sow Parity and Terminal Boar on Losses of Piglets and Pre-Weaning Growth Intensity of Piglets.

Simple SummaryThe production of piglets is influenced by a range of factors; among the most important are parity of sows and genotype, which is half determined by terminal boars. In this study, reproductive performance, losses of piglets, and growth of piglets were compared depending on the parity and effect of terminal boars. The number of reared piglets, which is considered the most important parameter in the breeding of sows, was not affected by the evaluated factors. However, evaluation of pre-weaning losses of piglets clearly showed the lowest values in the third parity sows. Additionally, piglets of purebred Duroc and Large Whitesirelinie boars showed the lowest losses before weaning and the highest growth intensity at the same time. In addition, the importance of studying interactions between factors was emphasized. These interactions revealed differences in some reproductive parameters and growth intensity of piglets in sows of a different parity after insemination with different terminal boars. The results show that the effect of terminal boars is crucial in the production of piglets. Based on the observed evaluation, the terminal boars of Duroc and Large Whitesirelinie breeds can be recommended as optimal for the production of piglets. This study analysed the effect of sow parity (P), terminal boars (TB), and their combination on reproductive parameters of sows, losses of piglets, and their individual live-weight (LW) and average daily gain (ADG) from birth to weaning. A total of 120 sows of Large White × Landrace hybrid combination from the first to the fourth parity (30 sows per parity) were included in the observation. The sows were inseminated by terminal boars of Pietrain (Pn), Large Whitesireline (LWSL), and Duroc (D) breeds and Duroc × Large Whitesirelinie (D × LWSL), Large Whitesirelinie × Pietrain (LWSL × Pn), and Duroc × Pietrain (D × Pn) hybrid combinations (20 sows per terminal boar population). The results proved a significant effect of P on the total numbers of piglets (TN), the numbers of stillborn piglets (SB), and the pre-weaning losses of piglets (L) (p ≤ 0.01) with the lowest losses found in the third parity sows. A significant effect of TB was confirmed for TN, the numbers of live-born piglets (LB), SB, the numbers of mummified piglets (M) and non-viable piglets (N), and (L) (p ≤ 0.01). The sows inseminated by D and LWSL boars showed the lowest total numbers of piglets but also the highest survivability of piglets until weaning. Significant effects of interaction between P and TB were observed for the TN, SB, N, and L (p ≤ 0.05). Evaluation of growth parameters in piglets (n = 1547) showed that P significantly influenced LW in the first three weeks of life (p ≤ 0.01) and ADG from birth to Day 7 and from Day 15 to Day 21 (p ≤ 0.01). Additionally, a significant effect (p ≤ 0.01) of TB was proven on individual weight and ADG in all the observed time intervals, with the highest growth found in the piglets of the D and LWSL boars. Significant interactions (p ≤ 0.01) between P and TB were found for LW and ADG in all the time intervals.

Environmental Enrichment for Pig welfare during Transport

ABSTRACT This study aimed to assess the effects of environmental enrichment for pigs during transportation in different phases of their productive cycle. Two trials were conducted, the first during transportation of pigs from the piglet production unit (PPU) to the nursery (n = 250) and the second during the transportation of nonhuman animals from the finishing unit (FU) to the slaughterhouse (n = 120). This work was an observational study with five environmental enrichments: Control – no enrichment; object – use of enrichment objects in the truck; aroma – use of lavender aroma in the truck; music – music in the truck; and vehicle sound. Animal behavior during transportation, respiratory rate, skin surface temperature, and skin lesion score were assessed. Piglets from the treatment music had the lowest frequency of agonistic behaviors during transportation from the farrowing to the nursery and lower skin temperature after transportation. Piglets from the control had the highest respiratory rate prior to transportation. Pigs familiarized with vehicle noises spent most of their time lying during the trip to the slaughterhouse. The creation of a familiar environment to pigs seems promising in enhancing animal well-being during transportation.

Synthetic Olfactory Agonist Use in the Farrowing House to Reduce Sow Distress and Improve Piglet Survival.

Simple SummaryWithin intensive livestock industries, it is important to pursue the continual improvement of animal welfare. The farrowing crate design in most piggeries is currently the best way to optimize piglet welfare and reduce piglet mortality caused by being crushed by the sow. However, some studies have shown that restriction in a farrowing crate exacerbates sow distress at specific times during farrowing at lactation, which may compromise piglet survival. Therefore, there is a need to investigate strategies that may alleviate the stress experienced by the sow due to being confined. A synthetic olfactory agonist, a commercial product that mimics naturally occurring pheromones, previously reduced aggressive interactions in sows. Therefore, this product was investigated to determine its effectiveness at reducing sow stress and improving piglet survival during birth and lactation. We found no effect on the sow’s stress hormone levels between treatments in response to a stressor. However, first-litter sows experienced a decreased farrowing duration, but this did not extend to improvements in piglet pre-weaning survival. This synthetic olfactory agonist does not appear to be a suitable tool to reduce sow distress around birth or improve piglet pre-weaning survival.The aim of the study was to investigate if the application of a synthetic olfactory agonist (SOA) would reduce indicators of stress in sows, in response to a stressor prior to parturition, and if it would improve farrowing house performance of sows and their piglets. Two studies were conducted: an intensive study with 47 sows, either having their first or second litter (Control n = 24; SOA n = 23); and a commercial validation study with 418 sows, either having their first litter or have had multiple litters (Control n = 210; SOA n = 208). Within the intensive study, sows were housed with or without a synthetic olfactory agonist suspended in the creep area of the farrowing crate, whereas within the commercial validation study, sows were housed with or without a synthetic olfactory agonist suspended over the adjoining creep area of two farrowing crates. Within the intensive study, despite a discernible increase in cortisol concentration in response to a stressor (snout rope test), cortisol response was not different between treatments (p > 0.05). Farrowing duration in first-litter sows exposed to the SOA was decreased (p < 0.001) whilst there was no impact on farrowing duration in second litter sows. Piglets were not attracted by the SOA to increase their utilisation of the creep area and spent more time in proximity to the sow (p < 0.05). Within the commercial validation study, no impacts were seen on piglet production measures (p > 0.05). Largely the use of an SOA within the farrowing house did not impact the sow or her piglets in either the intensive study or commercial validation study. Based on these current results, the use of SOA within the farrowing house is not supported.

How much the reproductive losses of sows can be impacting the carbon footprint in swine production?

Animal production influences the environment through land-use changes and the cycle of nutrients such as CO2. Pork production is an essential sector of agribusiness nowadays. This type of farming will also be affected by climate change since the production of animal feeds depends on the weather. New information on pork production is vital to study the amount of feed wasted through sow yield and environmental inefficiency on farms. Many sow indexes have been used in the last years, especially addressing reproduction efficiency. However, there is a lack of research on production losses from Greenhouse Gas emissions. The aim of the assessment was to estimate the daily feed intake of sows and the amount of feed consumed during their nonproductive days, correlating these results to greenhouse gas emissions. The variables were analyzed by the Life Cycle Assessment tool at Tier 3 level. The physiology of metabolic digestion related to sow respiration was calculated for each life stage. There were six Brazilian scenarios: 1 and 2 – farms from the Midwest region; 3 to 6 – different piglets systems from all regions. Producing piglets with 6.0 to 10.0 kg requires much time and feed intake, and feed processing depends on natural resources. Daily feed intakes during nonproductive days corresponded to 16,315.30 tons of total feed intake/year. Each scenario showed different results. For instance, Scenario 1 emitted 2.80 kg of CO2eq./kg of piglet, and Scenario 4 emitted 3.89 kg of CO2eq./kg of piglet. The environmental impacts analyzed lead us to conclude that the Brazilian production can be more efficient. Nonproductive days were harmful for weaned piglet production as the total feed intake of sows correlate with born alive and weaned piglets. Greenhouse Gas emissions can be included in sows yield calculation.

Effects of dietary Bacillus coagulans and yeast hydrolysate supplementation on growth performance, immune response and intestinal barrier function in weaned piglets.

The present study investigated the effects of Bacillus coagulans and yeast hydrolysate supplementation on growth performance, immune response and intestinal barrier function of weaned piglets. Twenty-four weaned piglets with an average body weight (BW) of 6.89±0.15kg were divided into four diets for 28days. The treatments were basal diet (control), basal diet supplemented with antibiotic (20mg/kg colistin sulphate and 40mg/kg bacitracin zinc, AT), probiotics (400mg/kg Bacillus coagulans ≥5×109CFU/g, BC) or yeast hydrolysate (5000mg/kg yeast hydrolysate, YH). Average daily gain (ADG) and average daily feed intake (ADFI) were improved by AT and YH diets (p<0.05), while BC diet only increased ADG (p<0.05). The complement 3 (C3), lysozyme (LZM) and tumour necrosis factor-α (TNF-α) concentrations in serum were increased in BC diet (p<0.05). Feeding AT and YH caused the increase of jejunal villus height (p<0.05), and a higher ratio of villus height/crypt depth was observed in AT, BC and YH groups (p<0.05). The mRNA expression of zonula occludens-1 (ZO-1) in jejunal mucosa was up-regulated by AT, BC and YH diets (p<0.05). Dietary AT, BC or YH inclusion decreased the interleukin-1β (IL-1β) concentration and TNF-α mRNA expression (p<0.05), and YH supplementation even down-regulated toll-like receptor 4 (TLR4) and CD14 expressions (p<0.05). In summary, the dietary administration of BC or YH both improves growth performance through promoting the intestinal barrier function, indicating both of them can serve as potential alternatives to antibiotics growth promoters for the piglet production.

Using PRRSV-Resilient Sows Improve Performance in Endemic Infected Farms with Recurrent Outbreaks.

Simple SummaryPorcine reproductive and respiratory syndrome (PRRS) is a viral disease responsible for huge economic losses to the pig industry. The selection of PRRSV resilient sows has been proposed as a strategy to control this disease. A simulation model was developed to test the differences in reproductive performance and economic outcome of resilient or susceptible sows under farm PRRSV endemic conditions with or without recurrent PRRSV outbreaks. The data from phenotyped sows came from a PRRSV-positive farm with 1500 sows that suffered a PRRSV outbreak that lasted 24 weeks within three years. The reproductive parameters were generally better for resilient than for susceptible sows in PRRSV-positive farms suffering recurrent PRRSV outbreaks. Consequently, the piglet production cost was lower for resilient than for susceptible sows in any condition but showed only significant differences in PRRSV endemic farms suffering recurrent outbreaks. Finally, the annual gross margin by sow is significantly better for resilient than for susceptible sows under endemic conditions with or without recurrent outbreaks. Thus, the selection of PRRSV resilient sows is always a profitable approach for producers supporting the control of this disease.The selection of porcine reproductive and respiratory syndrome (PRRS) resilient sows has been proposed as a strategy to control this disease. A discrete event-based simulation model was developed to mimic the outcome of farms with resilient or susceptible sows suffering recurrent PRRSV outbreaks. Records of both phenotypes were registered in a PRRSV-positive farm of 1500 sows during three years. The information was split in the whole period of observation to include a PRRSV outbreak that lasted 24 weeks (endemic/epidemic or En/Ep) or only the endemic phase (En). Twenty simulations were modeled for each farm: Resilient/En, Resilient/En_Ep, Susceptible/En, and Susceptible/En_Ep during twelve years and analyzed for the productive performance and economic outcome, using reference values. The reproductive parameters were generally better for resilient than for susceptible sows in the PRRSV En/Ep scenario, and the contrary was observed in the endemic case. The piglet production cost was always lower for resilient than for susceptible sows but showed only significant differences in the PRRSV En/Ep scenario. Finally, the annual gross margin by sow is significantly better for resilient than for susceptible sows for the PRRSV endemic (12%) and endemic/epidemic scenarios (17%). Thus, the selection of PRRSV resilient sows is a profitable approach for producers to improve disease control.

In vitro Electroporation in the Presence of CRISPR/Cas9 Reagents as a Safe and Effective Method for Producing Biallelic Knock-Out Porcine Embryos

The production of genetically modified (GM) pigs is considered valuable in biomedical research for the development of model animals for various diseases and pigs with resistance against viral infection. The porcine genome may be modified using several methods, such as somatic cell nuclear transfer (SCNT) using GM cells as the SCNT donor, direct injection of the transgene or the genome editing components (GEC) into fertilized eggs referred to as zygotes, the in vitro electroporation (EP) of the zygotes in the presence of GECs, viral infection using retroviruses, injection of the GECs into the SCNT-treated embryos, and the in vitro EP of the SCNT-treated embryos in the presence of GECs. In our previous study, we administered a cytoplasmic injection of CRISPR/Cas9-based GEC into parthenogenetically-activated porcine oocytes (referred to as parthenotes) and observed that these oocytes comprised a mixture of genome-edited and genome-unedited cells, referred to as the “mosaic”. In contrast, when in vitro EP of the SCNT-treated embryos in the presence of GEC was performed, bi-allelic knock out (KO) of the target gene was detected in most oocytes (82%; 9/11). The production of bi-allelic KO piglets is particularly beneficial for investigating GM domestic animals as it does not require further breeding trials to obtain bi-allelic KO individuals, which would otherwise be a time-consuming and laborious task. In this context, the present study was aimed to confirm the efficiency of in vitro EP in producing bi-allelic KO porcine embryos without multiple breeding trials, for which parthenotes were subjected to EP in the presence of a ribonucleoprotein containing Cas9 protein and single-guide RNA (targeted toward GGTA1). The treated embryos were cultured until they transformed into blastocysts. The genomic DNA isolated from these blastocysts was used for molecular biology analysis to detect the possible insertion and deletion of sequences (indels) at the GGTA1 locus. Among the 32 blastocysts obtained, 21 (66%) were observed to be the bi-allelic KO ones. The remaining embryos either had a normal phenotype (25%; 8/32) or mosaic mutations (9%; 3/32). These findings confirm the efficiency of in vitro EP in producing bi-allelic KO porcine embryos.

In vitro Electroporation in the Presence of CRISPR/Cas9 Reagents as a Safe and Effective Method for Producing Biallelic Knock-Out Porcine Embryos

The production of genetically modified (GM) pigs is considered valuable in biomedical research for the development of model animals for various diseases and pigs with resistance against viral infection. The porcine genome may be modified using several methods, such as somatic cell nuclear transfer (SCNT) using GM cells as the SCNT donor, direct injection of the transgene or the genome editing components (GEC) into fertilized eggs referred to as zygotes, the in vitro electroporation (EP) of the zygotes in the presence of GECs, viral infection using retroviruses, injection of the GECs into the SCNT-treated embryos, and the in vitro EP of the SCNT-treated embryos in the presence of GECs. In our previous study, we administered a cytoplasmic injection of CRISPR/Cas9-based GEC into parthenogenetically-activated porcine oocytes (referred to as parthenotes) and observed that these oocytes comprised a mixture of genome-edited and genome-unedited cells, referred to as the “mosaic”. In contrast, when in vitro EP of the SCNT-treated embryos in the presence of GEC was performed, bi-allelic knock out (KO) of the target gene was detected in most oocytes (82%; 9/11). The production of bi-allelic KO piglets is particularly beneficial for investigating GM domestic animals as it does not require further breeding trials to obtain bi-allelic KO individuals, which would otherwise be a time-consuming and laborious task. In this context, the present study was aimed to confirm the efficiency of in vitro EP in producing bi-allelic KO porcine embryos without multiple breeding trials, for which parthenotes were subjected to EP in the presence of a ribonucleoprotein containing Cas9 protein and single-guide RNA (targeted toward GGTA1). The treated embryos were cultured until they transformed into blastocysts. The genomic DNA isolated from these blastocysts was used for molecular biology analysis to detect the possible insertion and deletion of sequences (indels) at the GGTA1 locus. Among the 32 blastocysts obtained, 21 (66%) were observed to be the bi-allelic KO ones. The remaining embryos either had a normal phenotype (25%; 8/32) or mosaic mutations (9%; 3/32). These findings confirm the efficiency of in vitro EP in producing bi-allelic KO porcine embryos.

Early Immunocastration of Pigs: From Farming to Meat Quality.

Simple SummaryImmunocastration of boars to prevent boar taint in meat is usually performed during the fattening phase of pigs, which is sometimes impractical for pig fatteners. The aim of this study was to test the practicability of the immunization of suckling pigs against boar taint and to assess its influence on production performance and animal welfare in the fattening phase. The fattening and slaughtering performance as well as animal behavior and welfare did not differ between the standard and the earlier immunization. However, reliable avoidance of boar taint was not given for all animals when immunization was conducted very early at the piglet stage.The study aimed to test a very early immunization of pigs to prevent boar taint with regard to its practicability and influence on production performance, its reliability in ensuring good meat and fat quality, and animal welfare. Immunization was already conducted at piglet production stage and could be easily integrated into routine vaccination (week 3) and weaning practices (week 7). The fattening and slaughter performance of the animals was not affected by the immunization regime and was within the usual range. In addition, there were no abnormalities in animal behavior and the prevalence of injuries caused by aggressive interactions. All animals were classified as infertile on the basis of the histological examination of the testicles. However, the testosterone levels measured at slaughter were significantly higher in animals of the early immunization regime than in animals subjected to the standard immunization regime. Androstenone and skatole levels as the main components of boar taint were, on average, higher and varied to a greater extent in early immunized animals. Furthermore, the comparison of the immunization scheme did not result in significant differences for meat quality and for fatty acid composition.

Functional endocrine reserves of testes of boars of different breeds and indicators of their sperm

It is difficult to objectively assess the functional state of the endocrine gland based on the level of hormones in the blood, since hormones vary significantly in absolute values during the day. Therefore, to assess the functional state of the endocrine glands in biological and medical practice, "load" is used. The criterion for evaluating the state of the gland is the change in the concentration of secreted hormone by the endocrine gland in response to the stimulation. As is known, the testis reacts relatively quickly to stimulation with chorionic gonadotropin. This allows us to determine the limiting features of the hormone-synthesizing and hormone activity of the testes and determine the maximum response of the testes to this stimulation. The object of the study was 6-month-old boars of large white breed, Landrace and tempo, 10 heads from each breed. In order to determine the functional endocrine reserves of the testes at 6 months of age, CG (chorionic gonadotropin) was administered intramuscularly at a dose of 1000 IU. HCG was administered 3 times every 72 hours. Blood for the determination of testosterone was taken before administration of HCG and 2.12,24,48 and 72 hours after its administration. Testosteron was determined by the enzyme immunoassay. Sperm counts in 18-month-old boars were studied using standard methods. Performed three-fold loads with an interval of 72 hours showed that the hormone level increased to 7.2±0.6 nmol/l in a large white breed 72 hours after the first administration of HCG, in the Landrace breed to 7.9±0.5 nmol/l, in the Duroc breed to 7.0±0.7 nmol/l, in the tempo breed to 7.0±0.6 nmol/l. After the second injection HCG the testosterone levels in large white breed boars increased by 1.2 nmol/l, and breeds Duroc 1.7 nmol/l, Landrace 0.1 nmol/L. In the boar breed, tempo increased the hormone by 0.4 nmol/l. In this regard, the increase in testosterone in experimental boars continued, which means that the reserves of endocrine function of the testes were not fully realized, so the 3rd stimulation of HCG was also performed. In a large white breed of boars and Duroc, the maximum concentration of testosterone was observed 24 hours after administration of HCG and was 9.2±0.7 and 8.9±0.5 nmol/l respectively. In the Landrace and tempo breeds, the maximum concentration of testosterone was 2 hours after 3 CG stimulation and was 8.2±0.6 and 7.5±0.6 nmol/l. respectively. In terms of sperm, its fertilizing capacity and the production of live piglets per Farrow, the indicators were higher for boars of large white breed and Duroc.

Perception of Piggery Farmers towards Success Factors in Piglet Production in Mizoram, India

Perception of Piggery Farmers towards Success Factors in Piglet Production in Mizoram, India