Strategies to Improve Calf Performance: Improving Water Quality, Feeding Microbially-enhanced Soy Protein, and Supplementing Condensed Whey Solubles

Six experiments were conducted for this dissertation research to evaluate strategies to improve growth performance and health of calves. Growth performance, nutrient utilization, and health effects were evaluated when calves were offered water treated with reverse osmosis system (RW), fed starter pellets supplemented with microbially-enhanced soy protein (MSP) or supplemented condensed whey solubles (CWS). The first two experiments were conducted to determine drinking preference, growth performance, and health of dairy calves offered RW or by a municipal water treatment plant (MW), compared with local untreated well water (WW). First a sequential elimination study was conducted to observed drinking preference of calves given RW, MW and WW. Greater preference was observed calves fed RW and least was WW, with RW slightly preferred over MW. The second study was conducted to determine the effects of drinking RW versus MW on the growth performance and general health of calves. Total DMI and gain: feed, increased more over time for RW than MW. Water intakes were less in RW than MW, indicating more efficient water use. Frame growth, BW, nutrient utilization and blood metabolites were not different between treatments. Fecal scores tended to be less in calves on RW, with an interaction over time. The third and fourth experiments were conducted to determine effects of feeding calves starter pellets with MSP compared to soybean meal (SBM) with different milk replacers (MR) or with pasteurized milk. The third experiment demonstrated calves fed MSP at 23% of DM inclusion in starter pellets improved feed efficiency and maintained growth performance depending on MR. Next the fourth experiment was conducted to evaluate calves fed starter pellets with less inclusion of MSP (8% of DM basis) with pasteurized milk on growth performance and health. Calves fed MSP had greater DMI, and β-hydroxy butyrate (BHB) with similar BW and frame measurements between treatments. During the fifth and sixth experiments growth performance, nutrient utilization, and health were determine when calves were fed milk and starter pellets supplemented with CWS. In the fifth experiment during pre-weaning CWS were fed with milk and post-weaning CWS was top-dressed on starter pellets. Supplementing CWS improved starter intake, post-weaning BW, plasma concentrations of BHB, fecal scores, while maintaining frame growth. The sixth experiment was conducted on large commercial calf ranch to determine the effect of supplementing CWS on starter grain mix at low (CWSL) and high (CWSH) inclusion amounts throughout the first 12 wk of life. The DMI, BW, plasma concentration of BHB, and body condition scores were improved in calves fed CWSL while maintaining frame measurements and fecal and health scores. Improved water quality, feeding MSP, or supplementing CWS improved calf growth performance, nutrient utilization, and general health and offer new options for producers to improve calf performance

Effects of a water-soluble formulation of tylvalosin on disease caused by porcine reproductive and respiratory syndrome virus alone in sows or in combination with Mycoplasma hyopneumoniae in piglets

BACKGROUND: The effect of a water-soluble formulation of tylvalosin (Aivlosin® 625 mg/g granules) on disease caused by porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (Mhyop) was investigated in two animal studies. In a PRRSV challenge model in pregnant sows (n = 18), six sows received water medicated at target dose of 5 mg tylvalosin/kg body weight/day from 3 days prior to challenge until the end of gestation. Six sows were left untreated, with a third group remaining untreated and unchallenged. Sows were challenged with PRRSV-2 at approximately 85 days of gestation. Cytokines, viremia, viral shedding, sow reproductive parameters and piglet performance to weaning were evaluated. In a dual infection study (n = 16), piglets were challenged with Mhyop on days 0, 1 and 2, and with PRRSV-1 on day 14 and euthanized on day 24. From day 10 to 20, eight piglets received water medicated at target dose of 20 mg tylvalosin/kg body weight/day and eight piglets were left untreated. Cytokines, viremia, bacteriology and lung lesions were evaluated. RESULTS: In the PRRSV challenge study in pregnant sows, tylvalosin significantly reduced the levels of serum IL-8 (P < 0.001), IL-12 (P = 0.032), TNFα (P < 0.001) and GM-CSF (P = 0.001). IL-8 (P = 0.100) tended to be lower in uterus of tylvalosin sows. All piglets from tylvalosin sows surviving to weaning were PRRSV negative in faecal swabs at weaning compared to 33.3% PRRSV positive piglets from untreated sows (P = 0.08). In the dual challenge study in piglet, tylvalosin reduced serum IL1β, IL-4, IL-6, IL-8, IL-10, IL-12, IL-1α, IL-13, IL-17A, IL-18, GM-CSF, TGFβ1, TNFα, CCL3L1, MIG, PEPCAM-1 (P < 0.001) and increased serum IFNα, IL-1ra and MIP-1b (P < 0.001). In the lungs, tylvalosin reduced IL-8, IL-10 and IL-12 compared to untreated pigs (P < 0.001) and tended to reduce TNFα (P = 0.082). Lung lavage samples from all tylvalosin treated piglets were negative for Mhyop (0 cfu/mL) compared to the untreated piglets which had mean Mhyop counts of 2.68 × 10(4) cfu/mL (P = 0.023). CONCLUSION: Overall, tylvalosin reduced both local and systemic proinflammatory cytokines after challenge with respiratory pathogens in sows and in piglets. Tylvalosin was effective in reducing Mhyop recovery from the lungs and may reduce virus shedding in piglets following transplacental PRRSV infection in sows

Effects of a water-soluble formulation of tylvalosin on disease caused by porcine reproductive and respiratory syndrome virus alone in sows or in combination with Mycoplasma hyopneumoniae in piglets

Abstract Background The effect of a water-soluble formulation of tylvalosin (Aivlosin® 625 mg/g granules) on disease caused by porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (Mhyop) was investigated in two animal studies. In a PRRSV challenge model in pregnant sows (n = 18), six sows received water medicated at target dose of 5 mg tylvalosin/kg body weight/day from 3 days prior to challenge until the end of gestation. Six sows were left untreated, with a third group remaining untreated and unchallenged. Sows were challenged with PRRSV-2 at approximately 85 days of gestation. Cytokines, viremia, viral shedding, sow reproductive parameters and piglet performance to weaning were evaluated. In a dual infection study (n = 16), piglets were challenged with Mhyop on days 0, 1 and 2, and with PRRSV-1 on day 14 and euthanized on day 24. From day 10 to 20, eight piglets received water medicated at target dose of 20 mg tylvalosin/kg body weight/day and eight piglets were left untreated. Cytokines, viremia, bacteriology and lung lesions were evaluated. Results In the PRRSV challenge study in pregnant sows, tylvalosin significantly reduced the levels of serum IL-8 (P < 0.001), IL-12 (P = 0.032), TNFα (P < 0.001) and GM-CSF (P = 0.001). IL-8 (P = 0.100) tended to be lower in uterus of tylvalosin sows. All piglets from tylvalosin sows surviving to weaning were PRRSV negative in faecal swabs at weaning compared to 33.3% PRRSV positive piglets from untreated sows (P = 0.08). In the dual challenge study in piglet, tylvalosin reduced serum IL1β, IL-4, IL-6, IL-8, IL-10, IL-12, IL-1α, IL-13, IL-17A, IL-18, GM-CSF, TGFβ1, TNFα, CCL3L1, MIG, PEPCAM-1 (P < 0.001) and increased serum IFNα, IL-1ra and MIP-1b (P < 0.001). In the lungs, tylvalosin reduced IL-8, IL-10 and IL-12 compared to untreated pigs (P < 0.001) and tended to reduce TNFα (P = 0.082). Lung lavage samples from all tylvalosin treated piglets were negative for Mhyop (0 cfu/mL) compared to the untreated piglets which had mean Mhyop counts of 2.68 × 104 cfu/mL (P = 0.023). Conclusion Overall, tylvalosin reduced both local and systemic proinflammatory cytokines after challenge with respiratory pathogens in sows and in piglets. Tylvalosin was effective in reducing Mhyop recovery from the lungs and may reduce virus shedding in piglets following transplacental PRRSV infection in sows