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Prevention of transmission of African swine fever virus (ASFV) through contaminated feed ingredients and complete feed is an important component of biosecurity protocols for global feed supply chains. Use of extended storage times for feed ingredients has become a popular and emerging mitigation strategy that may allow partial inactivation of ASFV before manufacturing swine feeds. However, the effectiveness of this strategy is unclear because limited studies have been conducted using diverse methodologies and insufficiently sensitive measures of virus viability of only a few types of feed matrices. Therefore, interpretation of results from these studies has made providing prudent recommendations difficult. Furthermore, although a few studies have shown that feed is a plausible route of transmission of ASFV to pigs, there are conflicting findings on the infectivity of ASFV that may be present in feed, which may be related to the extent that ASFV is degraded in the pig's digestive system after it is consumed. Therefore, the objectives of this study were to use a surrogate ASFV-like algal virus (Emiliania huxleyi ; EhV) to determine stability in corn- and soybean-based feed ingredients and complete feed during a 120-day storage period at temperatures up to 34°C, and EhV survival in various feed matrices during three stages of an in vitro digestion process. Results indicated that inoculating corn- and soybean-based feed ingredients and complete feed with EhV and storing them at 4°C, 24°C, or 34°C for up to 120 days did not result in the complete inactivation of EhV in any of these matrices. Because EhV has similar environmental and thermal resilience to ASFV, these results indicate that both viruses can maintain viability in various feed matrices during long-term storage and suggest that extending storage time up to 120 days is not an effective mitigation practice against ASFV. We also determined that between approximately 5- to more than 7-log (99.999 to 99.99999%) reductions in EhV in various feed matrices occur during the entire in vitro digestion and fermentation process. These reductions appear to be correlated with the chemical composition of the matrices, potentially explaining inconsistencies in ASFV infection when pigs consume infectious doses of contaminated feed. [ABSTRACT FROM AUTHOR]

The objectives of this study were to determine a practical approach to feeding elevated dietary zinc (Zn) to gestating sows in a commercial setting and to confirm preweaning mortality could be reduced by feeding high Zn to sows during different periods of gestation. The study was conducted at a commercial sow farm in the upper Midwest. Mixed parity sows (n  = 267) over three consecutive weekly farrowing groups (sows farrowing within 1 wk) were assigned randomly to one of the three dietary treatments within parity. Treatments consisted of: (1) control sows fed a corn–soybean meal diet containing 206 mg/kg total supplemental Zn supplied by zinc hydroxychloride; (2) breed-to-farrow: as control + 147 mg/kg supplemental Zn as ZnSO4 (353 mg/kg total supplemental Zn) fed from 5 d after breeding to farrowing; and (3) day 110-to-farrow: as control fed from breeding to farrowing + 4,079 mg/kg supplemental Zn as ZnSO4 (4,285 mg/kg total supplemental Zn) starting day 110 of gestation until farrowing. At farrowing, individual piglets were weighed and identified within 12 h of birth. Data were analyzed using PROC GLIMMIX of SAS and the model considered the fixed effect of dietary treatment and random effect of farrowing group. Dietary treatments did not affect number of total pigs born per litter. For breed-to-farrow sows, there was an increase in the percentage of pigs born alive compared to sows fed the control and day 110-to-farrow treatments (P  < 0.001). The number of stillborn pigs expressed as a percentage of total litter size at birth decreased for breed-to-farrow sows (P  < 0.001) compared with control or day 110-to-farrow sows. Mortality of low birth weight piglets from birth to weaning did not differ among dietary treatments (P  = 0.305); however, a trend for decreasing post-natal mortality (P  = 0.068) of normal birth weight pigs was observed for pigs born to sows fed elevated Zn 5 d before farrowing. In conclusion, feeding elevated Zn to sows throughout gestation increased the proportion of pigs born alive suggesting that elevated gestational Zn intake makes piglets more robust to endure the stresses of farrowing and decreases intrapartum mortality. Under the conditions of this study, elevated Zn intake of sows did not influence piglet post-natal survival. However, feeding high zinc throughout gestation may decrease piglet mortality during the parturition process. [ABSTRACT FROM AUTHOR]

Simple Summary: Understanding the biological mechanisms associated with growth performance improvements that may occur when adding various feed additives to diets of weaned pigs fed is essential for their strategic and optimal use. The objective of this study was to evaluate the growth performance, metabolic profiles, and intestinal microbiome composition of nursery pigs fed various feed additives and to determine potential biological mechanisms associated with growth promotion. The growth performance responses of high-health weaned pigs (20 days of age) were determined in three separate 42 day experiments when fed antibiotics (chlortetracycline and sulfamethazine; PC), herbal blends, turmeric, garlic, bitter orange extract, sweet orange extract, volatile and semi-volatile milk-derived substances, yeast nucleotide, and cell wall products, compared with feeding a non-supplemented diet (NC). None of the feed additives except antibiotics significantly improved growth performance, compared with feeding NC. Furthermore, none of the dietary treatments affected the metabolome and microbiome profiles or alpha and beta microbiome diversity in the ileum and cecum. However, some additives, such as herbal blends and garlic, increased the relative abundance of certain bacteria genera in the ileal and cecal microbiome that may provide some protection for weaned pigs when experiencing disease challenge. The objective of this study was to determine the potential biological mechanisms of improved growth performance associated with potential changes in the metabolic profiles and intestinal microbiome composition of weaned pigs fed various feed additives. Three separate 42 day experiments were conducted to evaluate the following dietary treatments: chlortetracycline and sulfamethazine (PC), herbal blends, turmeric, garlic, bitter orange extract, sweet orange extract, volatile and semi-volatile milk-derived substances, yeast nucleotide, and cell wall products, compared with feeding a non-supplemented diet (NC). In all three experiments, only pigs fed PC had improved (p < 0.05) ADG and ADFI compared with pigs fed NC. No differences in metabolome and microbiome responses were observed between feed additive treatments and NC. None of the feed additives affected alpha or beta microbiome diversity in the ileum and cecum, but the abundance of specific bacterial taxa was affected by some dietary treatments. Except for feeding antibiotics, none of the other feed additives were effective in improving growth performance or significantly altering the metabolomic profiles, but some additives (e.g., herbal blends and garlic) increased (p < 0.05) the relative abundance of potentially protective bacterial genera that may be beneficial during disease challenge in weaned pigs. [ABSTRACT FROM AUTHOR]

Simple Summary: Global trade of feed ingredients that may be contaminated with significant concentrations of swine viruses is a concern for the potential transmission of swine diseases because viable virus particles can survive in feed ingredients and complete feed for several weeks or months. No global swine virus surveillance and monitoring system exists to determine the possible presence and concentrations of swine viruses in feed ingredients. Biosecurity protocols based on hazard analysis and risk-based preventive controls must be developed and implemented in feed ingredient supply chains to prevent virus contamination. In addition, mitigation strategies including the use of extended storage time, thermal and irradiation processing, and certain feed additives have been shown to provide partial virus inactivation in contaminated ingredients and complete feeds under specific conditions. However, analytical methods capable of accurately determining viable virus concentrations that can lead to infection are lacking and need to be developed. Effective feed mill decontamination strategies are also needed for various swine viruses. Several functional ingredients and nutrients such as spray-dried animal plasma, medium-chain fatty acids, and soy isoflavones have antiviral properties and have been shown to alleviate adverse health of pigs undergoing a viral disease challenge when included in diets. No system nor standardized analytical procedures at commercial laboratories exist to facilitate and accurately measure potential viable virus contamination in feed ingredients and complete feeds globally. As a result, there is high uncertainty of the extent of swine virus contamination in global feed supply chains. Many knowledge gaps need to be addressed to improve our ability to prevent virus contamination and transmission in swine feed. This review summarizes the current state of knowledge involving: (1) the need for biosecurity protocols to identify production, processing, storage, and transportation conditions that may cause virus contamination of feed ingredients and complete feed; (2) challenges of measuring virus inactivation; (3) virus survival in feed ingredients during transportation and storage; (4) minimum infectious doses; (5) differences between using a food safety objective versus a performance objective as potential approaches for risk assessment in swine feed; (6) swine virus inactivation from thermal and irradiation processes, and chemical mitigants in feed ingredients and complete feed; (7) efficacy of virus decontamination strategies in feed mills; (8) benefits of functional ingredients, nutrients, and commercial feed additives in pig diets during a viral health challenge; and (9) considerations for improved risk assessment models of virus contamination in feed supply chains. [ABSTRACT FROM AUTHOR]

Mycoplasma hyopneumoniae is the primary causative agent of enzootic pneumonia, one of the most common bacterial pathogens affecting pigs and the main contributor to respiratory comorbidities. Infection with M. hyopneumoniae, commonly observed in growing pigs, results in decreased feed intake and an increase in the number of days to reach market weight. Based on extended days to market, pigs infected with M. hyopneumoniae will have a greater life cycle carbon emissions and water usage than that of non-infected pigs. However, the magnitude of additional carbon footprint and water use in pigs infected with M. hyopneumoniae has never been calculated. Therefore, the objective of this study was to estimate the potential variation in carbon emissions and water footprint generated by M. hyopneumoniae infected pigs. This study was conducted using data from previous publications on M. hyopneumoniae infected pigs in experimental and commercial conditions. The carbon footprint and water usage of pork production was obtained from the literature and was used as a baseline (3,470 kg of CO2 eq and 1,678 m³ water eq; both per 1,000 kg of pork carcass weight). The change in average daily gain was estimated and additional days on feed to reach market weight were used to calculate potential carbon and water impact for pigs infected with M. hyopneumoniae. The estimated carbon emissions and water usage of M. hyopneumoniae infected pigs increased in a range of 84.69 to 142.93 kg of CO2 eq/1,000 kg of pork carcass weight and 40.95 to 69.12 m3 eq/1,000 kg of pork carcass weight respectively, compared with the carbon emissions of non-infected pigs (Table 1). Results of this study showed an increased carbon footprint for M. hyopneumoniae infected pigs by 2 to 4% and water usage increased by 2.5 to 4.1% suggesting that the sustainability of pork production was negatively affected by this bacterial infection. Previous literature on the impact of controlling vaccine-preventable diseases has shown similar results for other swine respiratory pathogens. In addition, these data only included M. hyopneumoniae infected pigs, thus the effect of respiratory co-infections was not estimated and the impact on sustainability metrics may be greater than currently calculated. The application of sustainable practices in animal production, including disease prevention, is key to ensuring a secure food supply for future generations. The carbon and water footprints of swine production are measurements of sustainability, with average daily gain being an important factor. [ABSTRACT FROM AUTHOR]