Feed and feeding strategies to alleviate common challenges in dairy cattle nutrition

De Freitas Cardoso, Fabiana

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https://hdl.handle.net/2142/117668 Copy

Description

Title

Feed and feeding strategies to alleviate common challenges in dairy cattle nutrition

Author(s)

De Freitas Cardoso, Fabiana

Issue Date

2022-12-02

Director of Research (if dissertation) or Advisor (if thesis)

C. Cardoso, Phil

Doctoral Committee Chair(s)

C. Cardoso, Phil

Committee Member(s)

• K. Drackley, James
• R. Murphy, Michael
• Smith, Xandra
• F. Brito, Andre C.

Department of Study

Animal Sciences

Discipline

Animal Sciences

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

Ph.D.

Degree Level

Dissertation

Keyword(s)

• Direct fed microbials
• transition period

Abstract

Improved animal health, performance, feed utilization, and food safety are important goals that can increase profitability to dairy farmers. Whole plant corn silage (WPCS) is the most common forage used in dairy cow diets in the United States and world-wide. Therefore, due to the importance of WPCS in a dairy farm, producers constantly seek practices to improve the nutritive value of WPCS. Producers can increase the cutting height at harvest, as an alternative to improve silage nutritive value through increased starch concentrations and NDF digestibility 30h (NDFD 30 h) and increase milk production in dairy cows. Additionally, the use of different microbial inoculants may speed up the post-ensiling decline in pH, improve aerobic stability, and enhance forage digestibility. The objective of the first study was to determine the effects of harvest cut height and inoculant application on brown mid-rib (BMR) WPCS yield, chemical composition, fermentative profile, and in vitro degradability. Corn was harvested at 31 to 35% dry matter (DM) in two different cut heights: low-cut height at 30.5 cm (LC) and high-cut height at 56 cm (HC). Three inoculants were used as treatments: CON (water; no inoculant), SA (Lactobacillus plantarum and Pediococcus pentosaceus), P2 (Propionibacteria freudenreichii and Pediococcus pentosaceus) and B500 (Lactobacillus buchneri and Pediococcus pentosaceus). Mini silos were opened at 5 different fermentation time points: 0, 2, 5, 30, and 90 d. Statistical analysis was performed using the MIXED procedure of SAS. Gross yield and DM yield of BMR WPCS was decreased for HC (23.1 × 103 kg and 7,400 kg/ha) compared to LC (28.0 × 103 kg and 8,600 kg/ha). In addition, HC increased the concentrations of BMR WPCS DM, crude protein (CP), starch, and predicted milk yield, and decreased the concentration of neutral detergent fiber (NDF) and acid detergent fiber (ADF). Treatment B500 had higher NDFD 30 h compared to P2 on d 30. The HC had lower acetic acid concentration compared to LC for CON and B500. The HC had a lower lactic: acetic acid ratio compared to LC for CON. The HC had a lower ammonia concentration compared to LC for CON. The HC tended to have lower total acids compared to LC for CON, SA, P2, and B500. The HC tended to have lower lactic acid compared to LC for CON, SA, P2, and B500. There was an interaction of height × days ensiled for total acids, acetic acid, lactic acid, volatile fatty acids (VFA) score, and pH. Increasing the cut height of BMR WPCS improves its nutritive value, as HC increased starch content and decreased ADF and NDF content. Inoculant application on BMR WPCS did not improve corn silage nutritive value, however, the inoculant B500 compared to P2 increased NDFD 30 h. The inoculant application on BMR corn harvested at 56 cm (HC) did not create a better fermentation environment for corn ensiled as WPCS. Altogether, these data can be helpful in the decision-making processes surrounding WPCS nutritive value, specifically regarding harvest cut height of corn. Clostridium contamination is a reality in feeds used for animal diets and farms environment. The occurrence of Clostridium in dairy farms is a concern for dairy producers because their spores can contaminate the soil, animal feed, TMR, and feces ). Paraclostridium bifermentans (PCB; formerly called Clostridium bifermentans), a non-toxigenic species is highly found in samples of TMR, corn silage, and haylage across the United States. The effects of PCB oral challenge on lactation performance, health, and metabolism in multiparous, lactating Holstein cows were determined. Thirty-nine Holstein cows were assigned to 1 of 3 PCB challenge concentrations in a randomized complete block design. The PCB challenge concentration was calculated to be one log higher than the average clostridia concentrations in the dietary TMR and was administered orally. Therefore, cows were divided into 4 treatments to contain zero (CON, control; no PCB challenge, 0 log), LOW (2.85 log CFU of PCB /g of TMR), MED (3.47 log CFU of PCB /g of TMR), or HIG (3.85 log CFU of PCB /g of TMR). Milk yield and dry matter intake (DMI) were obtained daily. Body weight (BW), body condition score (BCS), fecal grabs, fecal pH, milk components, blood and ruminal fluid and pH samples were measured every 2 weeks. A subset of 15 cows (CON, n = 3; LOW, n = 4; MED, n = 4; and HIG, n = 4) were ruminally cannulated and used for ruminal papillae (RP) biopsy for mRNA expression on the last day of week 10. Statistical analysis was performed using the MIXED procedure of SAS. There was a quadratic treatment effect for DMI and DMI by BW, where cows in CON, LOW, MED, and HIG consumed 23.3, 22.1, 23.1, and 24.7 kg/d of DM, respectively. Cows that received the PCB oral challenge tended to increase feed efficiency (ECM/DMI) compared to CON cows. There was a linear effect and a tendency for a quadratic treatment effect for feed efficiency (Milk/DMI). There was a tendency for a quadratic treatment effect, as well as a treatment × week interaction for ruminal pH. Cows that received the PCB oral challenge had RP 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2) mRNA expression downregulated compared to cows in CON and a quadratic treatment effect was observed. In conclusion, the PCB challenge increased feed efficiency and resulted in ruminal environment changes due to the decrease in ruminal pH and the downregulation of RP HMGCS2 mRNA expression. The transition period is a challenging period for high-producing dairy cows, and feed strategies are crucial to minimize the negatives impacts that may occur. Studies are focusing on feed additives with the aim of achieving high performance and profitability. Direct-fed microbials (DFM) may be utilized to modulate ruminal environment. However, the DFM mode of action are inconsistent among studies and seems to be affected by strains, dosage, dietary factors, and management . This research aims to provide a further understanding of feeding DFM Bacillus (B.) subtilis (20g/cow/d); naturally occurring clostridia (Clostridium (C.) beijerinckii) (4 × 106 cfu/d DM of TMR), and B. subtilis in combination with C. beijerinckii from -21 days relative to expected calving (DREC) until 70 days in milk (DIM) on performance of Holstein cows. Seventy-one multiparous Holstein cows, blocked by parity, previous 305-d mature-equivalent milk production, expected calving date, and BCS during the far-off dry period were assigned to 1 of 4 dietary treatments in a randomized, complete block design. Treatments consisted of TMR top-dressed prepartum and postpartum with B. subtilis (CER), C. beijerinckii (BJE), C. beijerinckii in combination with B. subtilis (CBJ), and neither C. beijerinckii or B. subtilis (CON). During the first week of the experiment, cows were fed a basal diet, and observations for the variables were used as a covariate. Cows were milked 2× per d and milk samples were taken on 7, 14, 28, 42, 56, and 70 d relative to calving (DRC). Milk yield and DMI were recorded daily; BW and BCS weekly. Colostrum was obtained from each cow at the first milking following calving and IgG concentration was recorded immediately following collection using a refractometer. Blood samples were taken for plasma analysis on d -25 ± 5 (utilized as a covariate), -8 ± 3, 7 ± 2, 28 ± 2, and 70 ± 2 DRC. Statistical analysis was performed using the MIXED procedure of SAS. There was a tendency for the contrast CER vs. CBJ for colostrum immunoglobulin G (IgG) yield (567 and 417 g for CER and CBJ respectively). There was a tendency for an interaction of treatment × week, where cows in CER had greater milk fat content (5.32 %) compared to those in BJE (4.60 %) in week 1; cows in CER had a greater (4.52 %) milk fat concentration compared to those in CON (3.73 %) in week 4; cows in CER had a greater (4.52 %) milk fat concentration compared to those in BJE (3.83 %) at week 4; cows in CER had a greater (4.52 %) milk fat concentration compared to those in CBJ (3.83 %) in week 4. During the first week after calving, cows receiving BJE produced greater milk protein and milk casein content compared to CER and CBJ. Cows in CER tended to have greater concentrations of triglycerides (TG) than cows in CON. Cows in CER had lower plasma gamma-glutamyl transferase (GGT) concentration compared to cows in CBJ. Cows in CER had greater concentrations of cholesterol than cows in CON. Cows in BJE had greater concentrations of total protein and globulin than cows in CON. In conclusion, CER seems to have a small effect on colostrum and milk components and increases blood biomarkers that can be related to liver function. However, C. beijerinckii fed alone or in combination with B. subtilis did not affect cows` performance or health.

Graduation Semester

2022-12

Type of Resource

Thesis

Copyright and License Information

Copyright 2022 Fabiana Cardoso

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