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Dias AS, Baker ALV, Baker RB, Zhang J, Zeller MA, Kitikoon P, Gauger PC. Detection and Characterization of Influenza A Virus Endemic Circulation in Suckling and Nursery Pigs Originating from Vaccinated Farms in the Same Production System. Viruses 2024; 16:626. [PMID: 38675967 PMCID: PMC11054297 DOI: 10.3390/v16040626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024] Open
Abstract
Inactivated influenza A virus (IAV) vaccines help reduce clinical disease in suckling piglets, although endemic infections still exist. The objective of this study was to evaluate the detection of IAV in suckling and nursery piglets from IAV-vaccinated sows from farms with endemic IAV infections. Eight nasal swab collections were obtained from 135 two-week-old suckling piglets from four farms every other week from March to September 2013. Oral fluid samples were collected from the same group of nursery piglets. IAV RNA was detected in 1.64% and 31.01% of individual nasal swabs and oral fluids, respectively. H1N2 was detected most often, with sporadic detection of H1N1 and H3N2. Whole-genome sequences of IAV isolated from suckling piglets revealed an H1 hemagglutinin (HA) from the 1B.2.2.2 clade and N2 neuraminidase (NA) from the 2002A clade. The internal gene constellation of the endemic H1N2 was TTTTPT with a pandemic lineage matrix. The HA gene had 97.59% and 97.52% nucleotide and amino acid identities, respectively, to the H1 1B.2.2.2 used in the farm-specific vaccine. A similar H1 1B.2.2.2 was detected in the downstream nursery. These data demonstrate the low frequency of IAV detection in suckling piglets and downstream nurseries from farms with endemic infections in spite of using farm-specific IAV vaccines in sows.
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MESH Headings
- Animals
- Swine
- Swine Diseases/virology
- Swine Diseases/epidemiology
- Swine Diseases/prevention & control
- Orthomyxoviridae Infections/veterinary
- Orthomyxoviridae Infections/virology
- Orthomyxoviridae Infections/epidemiology
- Influenza A virus/genetics
- Influenza A virus/immunology
- Influenza A virus/isolation & purification
- Influenza A virus/classification
- Influenza Vaccines/immunology
- Influenza Vaccines/administration & dosage
- Phylogeny
- Farms
- Animals, Suckling
- Vaccination/veterinary
- Endemic Diseases/veterinary
- Influenza A Virus, H1N1 Subtype/genetics
- Influenza A Virus, H1N1 Subtype/immunology
- Influenza A Virus, H1N1 Subtype/isolation & purification
- RNA, Viral/genetics
- Influenza A Virus, H3N2 Subtype/genetics
- Influenza A Virus, H3N2 Subtype/immunology
- Influenza A Virus, H3N2 Subtype/isolation & purification
- Influenza A Virus, H1N2 Subtype/genetics
- Influenza A Virus, H1N2 Subtype/isolation & purification
- Influenza A Virus, H1N2 Subtype/immunology
- Genome, Viral
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Affiliation(s)
- Alessandra Silva Dias
- Department of Preventive Veterinary Medicine, Minas Gerais State University, 6627 Antonio Carlos Avenue, Belo Horizonte 31620-295, MG, Brazil;
| | - Amy L. Vincent Baker
- Virus and Prion Research Unit, United States Department of Agriculture, National Animal Disease Center, Agricultural Research Service, 1920 Dayton Avenue, Ames, IA 50010, USA; (A.L.V.B.); (P.K.)
| | - Rodney B. Baker
- Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, 1800 Christensen Drive, Ames, IA 50011, USA; (R.B.B.); (J.Z.); (M.A.Z.)
| | - Jianqiang Zhang
- Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, 1800 Christensen Drive, Ames, IA 50011, USA; (R.B.B.); (J.Z.); (M.A.Z.)
| | - Michael A. Zeller
- Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, 1800 Christensen Drive, Ames, IA 50011, USA; (R.B.B.); (J.Z.); (M.A.Z.)
| | - Pravina Kitikoon
- Virus and Prion Research Unit, United States Department of Agriculture, National Animal Disease Center, Agricultural Research Service, 1920 Dayton Avenue, Ames, IA 50010, USA; (A.L.V.B.); (P.K.)
| | - Phillip C. Gauger
- Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, 1800 Christensen Drive, Ames, IA 50011, USA; (R.B.B.); (J.Z.); (M.A.Z.)
- Phillip Gauger of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1800 Christensen Drive, Ames, IA 50011, USA
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Rawal G, Almeida MN, Gauger PC, Zimmerman JJ, Ye F, Rademacher CJ, Armenta Leyva B, Munguia-Ramirez B, Tarasiuk G, Schumacher LL, Aljets EK, Thomas JT, Zhu JH, Trexel JB, Zhang J. In Vivo and In Vitro Characterization of the Recently Emergent PRRSV 1-4-4 L1C Variant (L1C.5) in Comparison with Other PRRSV-2 Lineage 1 Isolates. Viruses 2023; 15:2233. [PMID: 38005910 PMCID: PMC10674456 DOI: 10.3390/v15112233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 11/04/2023] [Accepted: 11/06/2023] [Indexed: 11/26/2023] Open
Abstract
The recently emerged PRRSV 1-4-4 L1C variant (L1C.5) was in vivo and in vitro characterized in this study in comparison with three other contemporary 1-4-4 isolates (L1C.1, L1A, and L1H) and one 1-7-4 L1A isolate. Seventy-two 3-week-old PRRSV-naive pigs were divided into six groups with twelve pigs/group. Forty-eight pigs (eight/group) were for inoculation, and 24 pigs (four/group) served as contact pigs. Pigs in pen A of each room were inoculated with the corresponding virus or negative media. At two days post inoculation (DPI), contact pigs were added to pen B adjacent to pen A in each room. Pigs were necropsied at 10 and 28 DPI. Compared to other virus-inoculated groups, the L1C.5-inoculated pigs exhibited more severe anorexia and lethargy, higher mortality, a higher fraction of pigs with fever (>40 °C), higher average temperature at several DPIs, and higher viremia levels at 2 DPI. A higher percentage of the contact pigs in the L1C.5 group became viremic at two days post contact, implying the higher transmissibility of this virus strain. It was also found that some PRRSV isolates caused brain infection in inoculation pigs and/or contact pigs. The complete genome sequences and growth characteristics in ZMAC cells of five PRRSV-2 isolates were further compared. Collectively, this study confirms that the PRRSV 1-4-4 L1C variant (L1C.5) is highly virulent with potential higher transmissibility, but the genetic determinants of virulence remain to be elucidated.
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Affiliation(s)
- Gaurav Rawal
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Marcelo N. Almeida
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Phillip C. Gauger
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Jeffrey J. Zimmerman
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Fangshu Ye
- Department of Statistics, Iowa State University, Ames, IA 50011, USA;
| | - Christopher J. Rademacher
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Betsy Armenta Leyva
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Berenice Munguia-Ramirez
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Grzegorz Tarasiuk
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Loni L. Schumacher
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Ethan K. Aljets
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Joseph T. Thomas
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Jin-Hui Zhu
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Jolie B. Trexel
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
| | - Jianqiang Zhang
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (G.R.); (M.N.A.); (P.C.G.); (J.J.Z.); (C.J.R.); (B.A.L.); (B.M.-R.); (G.T.); (L.L.S.); (E.K.A.); (J.T.T.); (J.-H.Z.); (J.B.T.)
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Forseth AK, Karriker LA, Millman ST, Stalder KJ, Parsons RL, Azarpajouh S, Johnson AK. Validation of Standing and Locomotion Scoring, Behavioral Assessments, and Mechanical Nociceptive Threshold Testing on Naturally Occurring Sow Lameness. Animals (Basel) 2023; 13:1801. [PMID: 37889730 PMCID: PMC10252076 DOI: 10.3390/ani13111801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 05/19/2023] [Accepted: 05/23/2023] [Indexed: 10/29/2023] Open
Abstract
The objective of this study was to validate standing and locomotion lameness scoring, mechanical nociceptive threshold testing, and behavioral profile tools for the diagnosis of naturally occurring lameness etiologies in pigs. A total of 55 crossbred gilts and sows obtained from a commercial farm were enrolled in the study; with sound pigs classified as controls (8) and the remainder as lame due to integumentary (20), musculoskeletal (15), and combinations of integumentary and musculoskeletal (12) etiologies. Standing and locomotion lameness, mechanical nociceptive threshold (MNT) test, pig-human interventions, and latency to complete an obstacle course were evaluated. Standing and locomotion lameness scoring systems, MNT, and pig behavior (latency) were capable of discriminating between animals with mild organic lameness and animals that were sound and may have utility on the farm for staff to use to identify and manage lame animals. In rare instances, the tools used here were able to discriminate between broad categories of lameness etiology.
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Affiliation(s)
- Anna K. Forseth
- Swine Medicine Education Center, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | - Locke A. Karriker
- Swine Medicine Education Center, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | - Suzanne T. Millman
- Veterinary Diagnostic and Production Animal Medicine and Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | - Kenneth J. Stalder
- Department of Animal Science, College of Agriculture and Life Sciences, Iowa State University, Ames, IA 50011, USA
| | - Rebecca L. Parsons
- Veterinary Diagnostic and Production Animal Medicine and Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | - Samaneh Azarpajouh
- Department of Animal Science, College of Agriculture and Life Sciences, Iowa State University, Ames, IA 50011, USA
| | - Anna K. Johnson
- Department of Animal Science, College of Agriculture and Life Sciences, Iowa State University, Ames, IA 50011, USA
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Hale BJ, Li Y, Adur MK, Keating AF, Baumgard LH, Ross JW. Characterization of the effects of heat stress on autophagy induction in the pig oocyte. Reprod Biol Endocrinol 2021; 19:107. [PMID: 34243771 PMCID: PMC8268447 DOI: 10.1186/s12958-021-00791-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/23/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Heat stress (HS) occurs when body heat accumulation exceeds heat dissipation and is associated with swine seasonal infertility. HS contributes to compromised oocyte integrity and reduced embryo development. Autophagy is a potential mechanism for the oocyte to mitigate the detrimental effects of HS by recycling damaged cellular components. METHODS To characterize the effect of HS on autophagy in oocyte maturation, we utilized an in vitro maturation (IVM) system where oocytes underwent thermal neutral (TN) conditions throughout the entire maturation period (TN/TN), HS conditions during the first half of IVM (HS/TN), or HS conditions during the second half of IVM (TN/HS). RESULTS To determine the effect of HS on autophagy induction within the oocyte, we compared the relative abundance and localization of autophagy-related proteins. Heat stress treatment affected the abundance of two well described markers of autophagy induction: autophagy related gene 12 (ATG12) in complex with ATG5 and the cleaved form of microtubule-associated protein 1 light chain 3 beta (LC3B-II). The HS/TN IVM treatment increased the abundance of the ATG12-ATG5 complex and exacerbated the loss of LC3B-II in oocytes. The B-cell lymphoma 2 like 1 protein (BCL2L1) can inhibit autophagy or apoptosis through its interaction with either beclin1 (BECN1) or BCL2 associated X, apoptosis regulator (BAX), respectively. We detected colocalization of BCL2L1 with BAX but not BCL2L1 with BECN1, suggesting that apoptosis is inhibited under the HS/TN treatment but not autophagy. Interestingly, low doses of the autophagy inducer, rapamycin, increased oocyte maturation. CONCLUSIONS Our results here suggest that HS increases autophagy induction in the oocyte during IVM, and that artificial induction of autophagy increases the maturation rate of oocytes during IVM. These data support autophagy as a potential mechanism activated in the oocyte during HS to recycle damaged cellular components and maintain developmental competence.
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Affiliation(s)
- Benjamin J Hale
- Department of Animal Science, Iowa State University, 2356 Kildee Hall, Ames, IA, 50011, USA
| | - Yunsheng Li
- Department of Animal Science, Iowa State University, 2356 Kildee Hall, Ames, IA, 50011, USA
| | - Malavika K Adur
- Department of Animal Science, Iowa State University, 2356 Kildee Hall, Ames, IA, 50011, USA
| | - Aileen F Keating
- Department of Animal Science, Iowa State University, 2356 Kildee Hall, Ames, IA, 50011, USA
| | - Lance H Baumgard
- Department of Animal Science, Iowa State University, 2356 Kildee Hall, Ames, IA, 50011, USA
| | - Jason W Ross
- Department of Animal Science, Iowa State University, 2356 Kildee Hall, Ames, IA, 50011, USA.
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Olsen KM, Gould SA, Patience JF. A comparison of the release of phosphorus by a phytase enzyme in pigs fed diets deficient or adequate in phosphorus content. J Anim Sci 2021; 99:skab001. [PMID: 33861853 PMCID: PMC8051844 DOI: 10.1093/jas/skab001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 01/06/2021] [Indexed: 12/27/2022] Open
Abstract
Previous research indicated that phytase may release less phosphorus (P) from phytate when it is evaluated using diets with P levels above requirement as compared with diets below requirement. The objectives of this experiment were to further test the hypothesis that the P release values determined for phytase are higher when pigs are fed diets that are deficient (DE) in P compared with when they are fed diets that are adequate (AD) in P, and that phytase will increase the digestibility of dry matter (DM), gross energy (GE), nitrogen (N), and calcium (Ca) independent of dietary P status. Twenty-four barrows (body weight: 23.2 ± 1.8 kg) were randomly assigned to one of eight dietary treatments and housed in individual pens for 21 d and then moved to metabolism crates for 9 d, with the collection of urine and feces occurring on the final 5 d. A basal corn-soybean meal diet (P-AD) was formulated at 0.36% standardized total tract digestible (STTD) P and total calcium:STTD P (Ca:STTD P) of 2:1. A P-DE diet was also formulated to maintain a constant Ca:STTD P of 2:1 in both basal diets. Phytase was added to AD and DE diets at 350, 600, 1,000 phytase units (FYT)/kg. Pig was the experimental unit; diet (P-AD or P-DE), phytase level, and replicate were fixed effects. Orthogonal polynomial contrasts were used to test linear and quadratic effects of phytase within P-AD and P-DE diets. Phytase improved apparent total tract digestibility (ATTD) and STTD of P in both P-AD (linear P < 0.001) and P-DE diets (quadratic P < 0.001). Estimates for STTD P release were 0.07%, 0.09%, and 0.09% for 350, 600, and 1,000 phytase units (FYT)/kg in P-DE diets, and 0.02%, 0.03%, and 0.05% in P-AD diets, respectively. In P-DE diets, phytase improved absorption and retention of P and increased urinary excretion of P (quadratic P < 0.001). In P-AD diets, phytase improved absorption of P (linear P = 0.066), tended to improve retention (linear P = 0.066), and increased urinary excretion of P (quadratic P = 0.021). Phytase improved ATTD of Ca in P-DE diets (quadratic P = 0.002) but not in P-AD diets (P > 0.1). In conclusion, the release of P by phytase is lower in diets that are AD in P than those which are DE. Phytase increased the availability of Ca only in the diets DE in P. Finally, phytase increased the ATTD of DM and tended to increase the ATTD of energy, independent of dietary P status.
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Affiliation(s)
- Kristin M Olsen
- Department of Animal Science, Iowa State University, Ames, IA 50011-1178
- Iowa Pork Industry Center, Iowa State University, Ames, IA 50011-1178
| | - Stacie A Gould
- Department of Animal Science, Iowa State University, Ames, IA 50011-1178
- Iowa Pork Industry Center, Iowa State University, Ames, IA 50011-1178
| | - John F Patience
- Department of Animal Science, Iowa State University, Ames, IA 50011-1178
- Iowa Pork Industry Center, Iowa State University, Ames, IA 50011-1178
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Acosta JA, Stein HH, Patience JF. Impact of increasing the levels of insoluble fiber and on the method of diet formulation measures of energy and nutrient digestibility in growing pigs. J Anim Sci 2020; 98:skaa130. [PMID: 32315034 PMCID: PMC7275632 DOI: 10.1093/jas/skaa130] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 04/18/2020] [Indexed: 12/27/2022] Open
Abstract
The objective of this study was to determine the differences in response to distillers dried grains with solubles (DDGS) level under constant nutrient or floating nutrient concentrations. A total of 21 ileal-cannulated gilts (33.1 ± 0.4 kg body weight) were randomly allotted to one of seven dietary treatments in a 3-period incomplete Latin square design (n = 9). Treatments consisted of a 0% DDGS basal diet, plus diets containing 15%, 30%, or 45% DDGS. Diets were formulated using one of two different formulation methods: 1) constant nutrient (CNU) where nutrients were held equal to the basal diet or 2) constant ingredients (CIN) where DDGS were added at the expense of corn and all other ingredients remained constant, so nutrient levels were allowed to "float." Chromic oxide was added to the diets at 0.5% as an indigestible marker. Increasing the level of DDGS decreased the apparent ileal digestibility (AID) of dry matter (DM), gross energy (GE), starch, dispensable amino acids (AA), and fiber components (P < 0.050). The decrease in the AID of Lys, Met, Thr, and Trp was more pronounced under CNU compared with the CIN formulation method (P < 0.050). The decrease in the AID of hemicellulose was less pronounced under CNU compared with the CIN formulation method (P = 0.045). There was a DDGS level × formulation method interaction for the AID of acid hydrolyzed ether extract (AEE; P = 0.015); for the CNU formulation method, increasing level of DDGS decreased the AID of AEE from 0% to 30% and remained similar from 30% to 45% DDGS, whereas the CIN had no effect on the AID of AEE. Increasing the level of DDGS decreased the apparent total tract digestibility (ATTD) of DM, GE, and fiber components (P < 0.050), except for acid detergent fiber, which was not affected. The decrease in the ATTD of insoluble dietary fiber and total dietary fiber was less pronounced under CNU compared with CIN (P < 0.050). The ATTD of AEE decreased for CNU compared with CIN (P < 0.010). In conclusion, increasing the insoluble fiber level in the form of DDGS decreased the digestibility of most dietary components, including DM, GE, starch, insoluble fiber, and AA. The CNU and CIN formulation methods are equivalent when evaluating the digestibilities of DM, GE, starch, crude protein, and AA (when they were not added in purified synthetic forms). Differences between CNU and CIN formulation methods were detected for the digestibility of insoluble fiber, fat, and essential AA (when added as crystalline AA).
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Affiliation(s)
- Jesus A Acosta
- Department of Animal Science, Iowa State University, Ames, IA
| | - Hans H Stein
- Department of Animal Sciences, University of Illinois, Urbana, IL
| | - John F Patience
- Department of Animal Science, Iowa State University, Ames, IA
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Abstract
It is important to understand if, and to what extent, the pig can utilize xylose as an energy source if xylanase releases free xylose in the small intestine. The experimental objectives were to determine the effects of industry-relevant dietary xylose concentrations and adaptation time on xylose retention efficiency and metabolism, diet digestibility and energy value, nitrogen balance, and hindgut fermentation. Forty-eight pigs were housed in metabolism crates and randomly assigned to one of four treatments with increasing D-xylose levels (n = 12/treatment) in 2 replications of a 22-d experiment with 3 collection periods. The control diet was xylose-free (0%), to which either 2, 4, or 8% D-xylose was added. Adaptation effects were assessed during three fecal and urine collection periods: d 5-7, 12-14, and 19-21. On d 22, pigs from the 0 and 8% treatments were euthanized; cecal and colon digesta were collected. Dietary xylose did not affect the total tract digestibility of dry matter, gross energy, or crude protein (P>0.10). Digesta short chain fatty acids concentrations and molar proportions and cecal pH were not different (P>0.10). This experiment utilized a targeted metabolomics approach to characterize and quantify urine xylose and metabolite excretion. Xylose retention decreased from 60% to 47% to 41% when pigs were fed diets containing 2, 4, or 8% xylose, respectively. In the 4 and 8% treatments, xylose retention was greater in the 2nd and 3rd collection periods compared to the 1st. A comprehensive pathway for xylose metabolism was proposed and D-threitol was confirmed as the major urinary metabolite of xylose. In conclusion, pigs can metabolize xylose, but with considerably lower efficiency than glucose, and may be able to adapt with time to utilize xylose more efficiently.
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Affiliation(s)
- Nichole F. Huntley
- Department of Animal Science, Iowa State University, Ames, IA, United States of America
| | - John F. Patience
- Department of Animal Science, Iowa State University, Ames, IA, United States of America
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