Laura L. Greiner

Iowa State University | ISU · Department of Animal Science

Diagnostic reports of biological samples submitted from farms are essential to correctly identify any underlying issues in a herd, including disease and improper nutrition. Proper sample collection, handling, and storage are critical to most accurately diagnose health complications or nutritional status. When possible, sample pigs before they eat,...

The objective of this experiment was to evaluate increasing the concentration of lysine on the compensatory gain of finishing pigs during their recovery period after being fed a 97% corn holding diet for 3 or 6 wk. One thousand six hundred and eighty pigs with a starting body weight of 73.5 ± 2.2 kg were blocked by starting body weight and assigned...

The objective of this study was to investigate the effects of dietary linoleic acid level and the ratio of linoleic acid:linolenic acid (LA:ALA) on the growth performance, expression of genes associated with lipid metabolism and inflammatory status of grow-finish pigs. A total of 300 growing pigs (BW = 41.1 ±6.3 kg) were randomly assigned to either...

Two groups of 240 pigs (PIC 337 × 1050, PIC Genus, Hendersonville, TN) were used to investigate the interactions between leucine, isoleucine, and valine on the growth performance of approximately 10 to 20 kg nursery pigs. At weaning, pigs were placed into 40 pens with three barrows and three gilts per pen and fed a common diet for three weeks. On d...

One hundred and fifty-two nursery pigs (PIC, Hendersonville, TN) were randomly assigned to mix sex pens and one of six dietary treatments in a 3 × 2 factorial. Diets included no added fat, 3% added choice white grease, or 3% added soy oil with either a supplemented vitamin A (for a total of 11,640 IU vitamin A/kg, Rovimix A 1000, DSM, Parsippany, N...

The objective of this study was to investigate the effects of dietary unsaturated and saturated fat ratio (U:S) and the ratio of linoleic and linolenic acid (LA:ALA) on the growth performance of grow-finish pigs and estrus detection of gilts. A total of 240 pigs with initial body weight (BW) 54.4 ± 5.5 kg were randomly assigned to a high (>1.8; HUS...

The objective of this experiment was to evaluate the impact of lowering floor space allowance in finishing hogs from 65 to 120 kg when fed high versus low energy diets on growth performance. Eighty-eight mixed-sex pens with 24 ± 1 pigs per pen were randomly assigned by weight in a complete block design to one of eight treatments in a 2 x 4 factoria...

Objective: Determine how sample handling affects nutrient analysis of fat-soluble vitamins and minerals. Materials and methods: In experiment 1, blood was collected in either plasma or serum blood tubes and exposed to 4 hours of light or wrapped in aluminum foil to protect from light. In experiment 2, blood was collected at hours 0, 1, 2, 3, 4, 6,...

Two hundred and forty newly weaned pigs (PIC, Hendersonville, TN) were used to determine if supplementing additional arginine (Arg) either in the water or in the feed, and the combinations thereof, improved intestinal integrity and growth performance in nursery pigs. Each of the 80 pens contained 3 pigs (21 ± 2 days of age) which were randomly allo...

The objective of this study was to investigate the effects of dietary metabolizable energy (ME) level and the ratio of linoleic acid:α-linolenic acid (LA:ALA) on the growth performance, lipid metabolism, circulatory and joint inflammatory status, and synovial fluid proteome of grow-finish pigs. A total of 224 pigs (BW = 41.5 ±6.1 kg; PIC Genus 337...

Finishing pigs (N = 224; 28.66 ± 1.90 kg bodyweight) were randomly assigned across 56 pens of either four barrows or gilts, and assigned to one of four diets: control (7,656 IU vitamin A/kg), control supplemented with vitamin A (4.36 ppm, Rovimix A 1000, DSM, Parsippany, NJ, US), control supplemented with beta-carotene (163.28 ppm, Rovimix β-Carote...

This study aimed to determine if supplementation of oxidized-beta carotene (OxC-Beta) improved sow reproductive performance, litter growth performance, vitamin A status, and ability to alter immune cells abundance in sows and piglets, subsequent litter performance, and nursery growth performance. At approximately d 60 of gestation and through the l...

Sow mortality has significantly increased throughout the world over the past several years, and it is a growing concern to the global swine industry. Sow mortality increases economic losses, including higher replacement rates, affects employees' morale, and raises concerns about animal well-being and sustainability. This study aimed to assess herd-...

Two hundred and forty barrows and gilts (DNA 600 X 241, DNA Genetics, Columbus, NE) with an initial body weight (BW) of 35.5 ± 4.2 kg were sorted into split-sex pens, blocked by initial body weight, and randomly allocated to one of three dietary treatments with eight pigs per pen and ten pens per treatment. Dietary treatments included a standard di...

Twenty-four gilts (PIC 337 x 1050, PIC Genus, Hendersonville, TN) with an initial body weight (BW) of 33.09±1.33 kg were used to investigate the effects of benzoic acid (BA) and a Bacillus-based direct-fed microbial (DFM) on the nutrient metabolism and manure gas emissions of growing pigs. Pigs were blocked by BW, placed into metabolism stalls, and...

Objective: The purpose of this study was to survey the vitamin and mineral levels in various pig tissues at different phases of the life cycle. Materials and methods: Forty-eight healthy pigs of different stages of production were used for sampling of different tissues. Seven sows and a minimum of 10 animals from each phase of production (suckling,...

Iowa State University (ISU) offers undergraduate certificates to demonstrate completion of a curriculum in a specialized area across various disciplines. The certificate has the significant benefit of allowing students to customize their curriculum and document the completion of an approved course of study. A Dairy Cattle Production Management Cert...

Forty sows (PIC Camborough 1050) from a single farm were randomly selected at 112 days of gestation to evaluate if gut bacteria transverse the blood system of the sow to deposit gut microbiota into colostrum for piglet gut inoculation via the entero-mammary pathway. Fourteen first-parity gilts and twenty third-parity sows were used for the study. A...

Approximately 1,200 pigs (DNA 241×600, Columbus, NE) at approximately 20 kg were randomly allocated into sixty pens (20 pigs/pen) within 3 treatments to evaluate different feeder styles (conventional dry feeder (Dry), PigEasy (PE) wet/dry (PigEasy, Templeton, IA), or Crystal Springs(CS) wet/dry (Crystal Springs, Brandt, SD). Diets for the study wer...

The objective of this study was to evaluate the effect of fat inclusion level and fat source with supplementation of either vitamin A (ROVIMIX A 1000; DSM; NJ) or beta-carotene (ROVIMIX β-Carotene 10%; DSM; NJ) on growth performance and vitamin A, D, and E status of nursery pigs (n = 216; 5.81 ± 0.92 kg). The study was a 3 X 2 factorial with main e...

The objective of this experiment was to evaluate the degree of compensatory gain in finishing hogs when fed increasing levels of lysine during the re-alimentation period after being fed a restrictive 97% corn diet for 3 or 6 weeks. One hundred and forty mixed-sex pens (DNA Genetics, Columbus, NE) with a starting body weight of 73.5 ± 2.2 kg were bl...

Vitamins are crucial for day-to-day function in the body. They are often collected in studies to ensure that the body is functioning normally, but the ways in which these samples are collected are inconsistent. Therefore, the objective of this study was to evaluate differences in sampling collection methods. A total of 4 blood tubes (2 serum and 2...

Postpartum metritis, or the inflammation of the uterus after parturition, is often a direct result of bacterial infection and considered to contribute to agalactia / dysgalactia in multiple species. Diagnosing metritis has included evaluation of vaginal and cervical fluid (CF) discharge for signs of infection (i.e., purulent discharge, strong odor,...

The objective was to investigate the effects of dietary unsaturated:saturated fat ratio (U:S) and the fatty acid ratio of linoleic acid:linolenic acid (n6:n3) on growth performance of grow-finish pigs. A total of 240 pigs with initial body weight (BW) 54.4±5.5kg were randomly assigned to a high (> 1.8; HUS) or low (< 1.0; LUS) U:S ratio with a high...

The objective of this analysis was to investigate the effect of pig phenotype on growth restriction and compensatory ability after receiving a nutrient-deficient (97% corn) diet for 3 or 6 weeks. Sixteen hundred and sixty mixed-sex pigs (DNA Genetics, Columbus, NE) were tagged with radio frequency identification tags (LeeO, Prairie Systems, Spencer...

Agalactia is characterized by reduced milk production after farrowing, resulting in economic losses due to increased piglet mortality. Although a variety of management factors have been associated with the etiology of agalactia, a specific causative mechanism has not been identified. Since clinical signs of agalactia develop in the days following f...

Two hundred and forty newly weaned pigs (PIC, Hendersonville, TN) were used to determine if supplementing with additional arginine either in the water or in the feed, and the combinations thereof, improved intestinal integrity and growth performance in the nursery. Three pigs (21 ± 2 d) per pen for a total of 80 pens, within 4 water lines, were ran...

Twenty-four gilts (PIC 337X1050, PIC Genus, Hendersonville, TN) with initial bodyweight (BW) 33.09±1.33kg were used to investigate the effects of benzoic acid (BA), with or without a Bacillus-based direct-fed microbial (DFM), on the nutrient metabolism and gas emissions of growing pigs. Pigs were blocked by BW, placed into metabolism stalls, and ra...

Forty sows (PIC Camborough 1050) from a single farm were randomly selected at 112 d of gestation to evaluate if gut bacteria transverse the blood system of the sow to deposit gut microbiota into colostrum for piglet gut inoculation via the entero-mammary pathway. Fourteen first-parity gilts and twenty third-parity sows were used for the study. At t...

The objective of this experiment was to evaluate the impact of reducing floor space allowance in finishing hogs with a starting body weight (BW) of 65 ± 2 kg when fed high versus low energy diets on growth performance. Mixed-sex pens (n=88) with 24 ± 1 pigs per pen were blocked by starting BW to a randomized complete block design with eight treatme...

As reproductive performance of sows in the commercial U.S. sow herd continues to improve, advancing the impact of gestation and lactation diet supplementation is critical. Beginning on d 60 of gestation through lactation, sows (blocked by parity) were assigned to a standard gestation diet (n = 88), or the standard diet supplemented with 80 ppm OxC-...

Coronavirus Disease 2019 (COVID-19) was declared a global pandemic on March 11, 2020 by the World Health Organization and its impact on animal agriculture in the United States was undeniable. By April, COVID-19 resulted in the simultaneous closure or reduced operations of many meat processing plants in the upper Midwest, leading to supply chain dis...

Iowa State University (ISU) offers undergraduate certificates to demonstrate completion of a focused study in a specialized area across a variety of disciplines. The certificate has the significant benefit of allowing students to customize their curriculum and document an approved course of study. A Swine Production Management Certificate is now of...

owa State University (ISU) offers undergraduate certificates to demonstrate completion of a focused study in a specialized area across a variety of disciplines. The certificate has the significant benefit of allowing students to customize their curriculum and document completion of an approved course of study. A Beef Cattle Production Management Ce...

Iowa State University offers undergraduate certificates to demonstrate completion of a focused study in a specialized area. The certificate has the significant benefit of allowing students to customize their curriculum and document an approved course of study. An Equine Science and Management Certificate is offered within the Animal Science Departm...

Iowa State University (ISU) offers undergraduate certificates to allow students to customize their curriculum and demonstrate completion of focused study in a specialized area across a variety of disciplines. The Poultry Production Management Certificate is offered within the Animal Science Department at ISU and integrates technical topics in anima...

Coronavirus Disease 2019 (COVID-19) was declared a global pandemic on March 11, 2020, by the World Health Organization. By April 2020, COVID-19 resulted in the simultaneous closure or reduced operations of many processing plants in the upper Midwest, which quickly resulted in supply chain disruptions. Iowa is the leading pork production and process...

The objective of this study was to investigate the effects of dietary metabolizable energy level and the ratio of linoleic acid:linolenic acid (n6:n3) on the growth performance and inflammatory status of grow-finish pigs. A total of 240 growing pigs (BW = 41.5 ± 6.1 kg) were randomly assigned to either a high (3.55 Mcal/kg; HE) or low (3.29 Mcal/kg...

The objective of this study was to determine if benzoic acid in combination of a direct fed microbial could improve grow-finish performance in swine. Three hundred and twenty (DNA 600 X 241, DNA Genetics, Columbus, NE) barrows and gilts were used to evaluate the effect of benzoic acid (BA; VevoVitall, DSM Nutritional Products, Parsippany, NJ) with...

The objective was to investigate the effects of dietary linoleic acid level and the ratio of linoleic acid:linolenic acid (n6:n3) on the growth performance and inflammatory status of grow-finish pigs. A total of 300 growing pigs (BW = 41.1 ± 6.3 kg) were randomly assigned to either a high (30 g/kg; HLA) or low (15 g/kg; LLA) linoleic acid level wit...

Although pork producers typically aim to optimize growth rates, occasionally it is necessary to slow growth, such as when harvest facility capacity is limited. In finishing pigs, numerous dietary strategies can be used to slow growth so pigs are at optimal slaughter body weights when harvest facility capacity and/or access is restored. However, the...

The impact of maternal influence across all species on lifelong health and performance is a topic that while recognized as important in the past was not heavily explored until more recently. Over the years, production has focused on sow nutrition and its role in improving birth weights and weaning weights. Today’s sow has approximately 3 more pigs...

Four hundred and eighty (PIC 337 X 1050, PIC Genus, Hendersonville, TN) pigs were used to evaluate a novel threonine source (ThrPro, CJ America-Bio, Fort Dodge, IA) for nursery pigs from approximately 7 kg to 20 kg. At weaning, pigs were sorted by gender and fed a common diet for one week. Upon completion of the first week, pigs were sorted into ra...

The objective was to determine the effects of metabolizable energy (ME) and standardized ileal digestible (SID) lysine (Lys) levels on lactating sows and litter performance. A total of 600 sows (Camborough; PIC, Hendersonville, TN) were blocked by parity (P1, P2, P3+) on d 112 of gestation and allotted to 1 of 6 treatments arranged in a 2 x 3 facto...

Pre-wean mortality (PWM) is a multifaceted problem facing the US swine industry. The objective of this study was to compare the occurrence of mortality and age of piglets between a novel heat source (HS; semi-enclosed heated microclimate; SEHM) and a conventional heat lamp setup. This study was conducted in two rooms at a 1,000 head commercial sow...

Over the last 25 years, the sow has developed to have a leaner body mass to address the need for leaner, fast growing offspring. The leaner body mass results in a female that biologically can have a lower feed intake. Furthermore, the number of pigs born per litter and milk production have also increased during the same timeframe. Much research has...

Four hundred and eighty (PIC 337 X 1050, PIC Genus, Hendersonville, TN) pigs were used to evaluate a novel threonine source (ThrPro, CJ America – Bio, Fort Dodge, IA) for nursery pigs from approximately 7 to 20 kg body weight. After weaning, pigs were sorted by sex and fed a common diet for one week. Upon completion of the first week, pigs were sor...

Five experiments were conducted to evaluate the lysine requirements of lactating sows. All diets were formulated to be isocaloric 3.46 Mcal ME/kg and met or exceeded NRC (1998) recommendations. In all studies, sow feed intake, body weight loss/gain, subsequent reproduction and litter growth rate were evaluated. The data was analyzed as randomized c...

Pre-weaning morality (PWM) is attributed to a poor creep area microclimate and causes major economic and productivity losses for the US swine industry. Piglets need supplementary heat to overcome a high surface area to body weight ratio and minimal thermoregulation. A pilot-scale study was conducted to evaluate a semi-enclosed heated microclimate (...

This study tested whether supplemental melatonin given to mimic the extended nighttime melatonin pattern observed in the higher fertility winter season could minimize infertility during summer and fall in swine. Exogenous melatonin was fed during periods coinciding with follicle selection, corpus luteum formation, pregnancy recognition and early em...

Two hundred sows (Camborough, PIC, Hendersonville, TN) at d 35 post-breeding were enrolled into one of four treatments to assess the required arginine level for sow reproduction. For gilts, the grams of arginine and standardized ileal digestibility (SID) per treatment consisted of: 102 g/0.69% (T1), 107 g/0.73% (T2), 112 g/0.77% (T3), and 121 g/0.8...

Four hundred (PIC 337 X Camborough, PIC, Hendersonville, TN) and 800 (PIC 359 X C29) barrows and gilts were used to determine the impact of avilamycin (Kavault®, Elanco, Greenfield, IN) on nursery pig performance. Upon weaning, the lightest 10% of pigs were sorted off to form one replication and the remaining pigs were sorted by sex and placed into...

Approximately 1,200 weaned pigs (8.8 ± 1 kg; Camborough×337, PIC, Hendersonville, TN) were used to evaluate the effects of a blend of essential oils compared to therapeutic programs [negative control (NC), Carbodox (NC + 55 ppm Mecadox, Phibro, Teaneck, NJ; MX), added ZnO and CuSO4 (NC + 2,000 ppm Zn and 150 ppm Cu in P1 and 150 ppm Cu in P2; ZnCu)...

Two hundred and forty sows (Camborough, PIC, Hendersonville, TN) were started on study at 35 d post-breeding through lactation to determine the effects of soluble concentrated yeast product (Celmanax SCP, Arm and Hammer, Princeton, NJ) on sow and litter performance. Sows were fed their respective dietary treatments: 1) Control diet gestation x cont...

Camborough PIC sows (n = 291) were fed 1 of 5 dietary treatments to evaluate the standardized ileal digestible (SID) Thr:Lys requirement during lactation. Sows were blocked by parity (1, 2, and 3+) and randomly allotted to 1 of 5 SID Thr:Lys ratios (52, 60, 68, 76, and 84). SID Lys was formulated to 1.03% and SID methionine and cystine (M + C):Lys...

An experiment was conducted with 430 sows (PIC Camborough, PIC, Hendersonville, TN) to evaluate the ideal standardized ileal digestible (SID) Val:Lys on sow and litter performance during an 18.6-d lactation period. The SID Val:Lys ratios measured were based on previously published literature and then values above and below reported values. Sows wer...

Background: The use of feed grade amino acids can reduce the cost of lactation feed. With changing genetics, increasing feed costs, and higher number of pigs weaned with heavier wean weights further evaluation of higher inclusion levels of feed-grade amino acid in lactation diets than previously published is warranted. Two experiments (Exp.) were...

The objective of this study was to evaluate the effects of two dietary feeding periods of tiamulin in combination with chlortetracycline for the control and treatment of swine respiratory and enteric disease and subsequent growth performance. The study used 1,151 commercial crossbred barrows and gilts in a randomized complete block design. Pigs wer...

One thousand two hundred PIC (337 × Camborough; PIC, Hendersonville, TN) barrows and gilts were used to evaluate lactose levels and organic acid inclusion in newly weaned nursery pigs. At the start of the study, the pigs averaged 6.09 kg. The lightest 10% of pigs were sorted off to form one replication and the remaining pigs were sorted by gender a...

An experiment was conducted with 430 sows (PIC Camborough) to evaluate the ideal standardized ileal digestibile (SID) Val:Lys on sow and litter performance during a 23-d lactation period. The SID Val:Lys ratios measured were based on previously published literature and then values above and below reported values. Sows were randomly allotted within...

One thousand two hundred PIC (337 × Camborough; PIC, Hendersonville, TN) barrows and gilts were used to further evaluate the Standardized Ileal Digestible (SID) total sulfur amino acid (TSAA) ratio relative to lysine requirement in 14-27.5 kg nursery pigs. Prior to the start of the study, pigs were fed a basal diet that contained 1.45% SID lysine f...

One hundred and sixty sows (PIC Camborough, PIC, Hendersonville, TN) were allocated by parity block (parity 1 vs parity 2+) to one of four dietary 0.00%, 0.05%, 0.15%, or 0.25% fenugreek (Nutrifen, Furst McNess, Johnston, IA) starting at d90 of gestation. All diets were formulated to meet or exceed NRC (2012). Sows were porcine reproductive respira...

One thousand one hundred and ninety-one PIC (337 X Camborough) barrows and gilts were used to determine the impact of adding potassium chloride and choline chloride to diets containing high feed grade amino acids. Prior to the start of the study, pigs were fed a basal diet that contained 1.35% SID lysine for three weeks. At the start of the study,...

This study was conducted to determine the risk of porcine reproductive and respiratory virus (PRRS) infection through feed using a PRRS modified live virus vaccine (MLV) mixed in feed as a model, and to determine if treating feed with Sal CURB [(SC) Kemin Industries, Des Moines, IA] reduced the risk of PRRS transmission through feed. Pigs (N=24; 21...

An experiment was conducted with 351 sows (PIC Camborough) to evaluate the effects of SID lysine intake on sow and litter performance during a 23-d lactation period. Sows were randomly allotted within parity block (parity 1, parity 2, and parity 3+) to one of five corn soybean meal based lactation diets formulated to contain different levels of SID...

Three hundred and fifteen primiparous and multiparous sows were evaluated in a study to determine the effect of standardized ileal digestible (SID) Trp:Lys ratio in lactating sow diets. Camborough sows (PIC USA, Hendersonville, TN) ranging from first parity to eighth parity were blocked by parity and randomly allotted to 1 of 4 experimental diets c...

A total of 1,200 PIC 337 × 1050 barrows and gilts (11.4 ± 1.4 kg) were placed in a wean-to-finish facility. The 5 dietary treatments were 1.10, 1.20, 1.30, 1.40, and 1.50% SID lysine. Dietary treatments were randomly allotted to pens (25 pigs/pen) blocked by gender and average pen BW. Pigs were started on experimental diets at approximately 11.4 kg...

Ninety-three sows (Camborough PIC) were used to evaluate the effects of dietary calcium (Ca) inclusion rate in lactating sows. Sows were allotted at the end of gestation into a RCBD (Block = Parity ≤ P2 or ≥ P3) with the following feed treatments: 0.63 vs. 0.79 vs. 0.95% total Ca with total phosphorus (P) constant at 0.63% and available P constant...

A total of 1,113 pigs (36 ± 1.67 kg BW) were used in a 36-d study conducted as a RCBD (block = start BW) in a commercial wean-to-finish facility. Pigs were randomly allocated to the following dietary treatments: 1) Trt1, no feed disinfection/no synthetic Lys; 2) Trt2, feed disinfection (Sal CURB, Kemin)/no synthetic Lys; 3) Trt3, no feed disinfecti...

Approximately 1,200 (400 PIC 337 × 1050 and 800 PIC 359 × C29) barrows and gilts (26.5 ± 1.9 kg) were used to evaluate 3 different SID Lys:ME ratio programs in grow–finish. Experimental diets were fed in 5 phases (26–41, 41–55, 55–82, 82–105, and 105–114 kg) with 1 of 3 SID Lys:ME ratio programs (Current, New, and Economical). The SID Lys:ME ratios...

Camborough PIC sows (n = 291) were fed one of five dietary treatments to evaluate the SID Thr:Lys requirement during lactation. Sows were blocked by parity (1, 2, and 3+) and randomly allotted to one of five SID Thr:Lys ratios (52, 60, 68, 76, and 84). SID Lys was formulated to 1.03% and SID M+C:Lys was 55%. Sows were allowed 5.45 kg/day starting o...

Objectives: To estimate the impact of environmental conditions and management practices on the likelihood of cross-contamination of a pig transport vehicle with porcine reproductive and respiratory syndrome virus (PRRSV) during market-animal unloading. Materials and methods: An experimental model was developed to simulate indirect contact involving...

Variation in gilt fertility is associated with increased replacement and reduced longevity. Stress before breeding is hypothesized to be involved in reduced fertility. This study tested the timing of gilt relocation from pens to individual stalls before breeding on fertility and well-being. The experiment was performed in replicates on a commercial...

Objective: To compare areas within feed mills to determine the likelihood of presence of either porcine epidemic diarrhea virus (PEDV) or porcine delta coronavirus (PDCoV). Materials and methods: Twenty-four feed mills from various regions in the United States were evaluated. Swab samples (foot pedals of feed delivery trucks, bulk ingredient unload...

Porcine epidemic diarrhea virus (PEDV) causes a severe clinical enteric disease in suckling neonates with up to 100% mortality, resulting in devastating economic losses to the pork industry in recent years. Maternal immunity via colostrum and milk is a vital source to neonates of passive protection against diarrhea, dehydration and death caused by...