The effects of increasing amounts of milk replacer powder added to whole milk on passage rate, nutrient digestibility, ruminal development, and body composition in dairy calves

Hypertonic milk replacers are commonly used in animal production systems and their effect on the gastrointestinal system of young animals is insufficiently studied. Total lactose inclusion or its partial replacement with dextrose increases intestinal osmotic pressure, which may compromise gastrointestinal barrier function. In this experiment, we investigated the effect of increased osmolality of calf milk replacer (CMR) on gastrointestinal permeability in 30 Holstein Friesian (n = 17) or crossbred (n = 13) bull calves. The osmolality of CMR increased as result of a gradual replacement of lactose by monosaccharides (dextrose and galactose). Calves were acquired from dairy farms that followed a standardized protocol for colostrum management, including 3 feedings of colostrum in the first 24 h. Calves were then transported to the research facility between 0 and 3 d of age, fed a milk replacer with 0% dextrose twice daily for the first 2 wk of age, and subsequently exposed to their respective treatments from 3 until 7 wk of age. Meal size was 3.2 L at 3 wk of age and increased to 3.5 L at 7 wk of age. No solids were provided throughout the study and calves had ad libitum access to water. Treatments included 4 levels of dextrose inclusion (replacing lactose): 0% (L1, n = 5), 13.3% (L2, n = 5), 26.7% (L3, n = 5), and 40% (L4, n = 5) and an additional treatment (G+D, n = 10) that included 20% galactose and 20% dextrose and matched the galactose supply of L1 and the osmolality of L4. Carbohydrates were exchanged based on hexose equivalents. Across treatments, the estimated osmolality ranged from 439 (L1) to 611 mOsm/kg (L4 and G+D). Gastrointestinal permeability was assessed by fractional urinary recovery of indigestible markers (lactulose, d-mannitol, and Cr-EDTA) delivered as a single dose at 3 and 7 wk of age. Marker recoveries were expressed as percentage of oral dose and assessed in 6-h and 24-h quantitative urinary collections. Increasing the osmolality of the CMR linearly increased urinary Cr-EDTA and lactulose recoveries at 3 and 7 wk of age. Lactulose and Cr-EDTA recoveries did not differ between G+D and L4, suggesting that the source of monosaccharide (dextrose and galactose) in CMR had no effect on gastrointestinal permeability. The observed increase in gastrointestinal permeability to large molecules (Cr-EDTA and lactulose) with increased osmolality suggests that hypertonic CMR may compromise gastrointestinal barrier function.

Section: Discussionsupporting

confidence: 90%

Hypertonic milk replacers increase gastrointestinal permeability in healthy dairy calves

Wilms¹,

Berends²,

Martín-Tereso³

2019

“…In the present study, all animals were evaluated at the same age and we found no difference in BW and ADG in the studied periods, which may justify the absence of differences in mammary fat pad among groups. These results, combined with those observed by Azevedo et al (2016b), who reported no change in the percentage of fat in the body composition of male dairy calves receiving liquid feed with TS concentrations similar to that used in the present study, support the hypothesis of a similar effect on body composition and mammary gland of heifers.…”

Section: Mammary Glandsupporting

confidence: 92%

“…Total DM and water intake up to 240 d of age were similar among treatments and increased with age (P ≤ 0.01; Table 2). Azevedo et al (2016b) demonstrated that male calves receiving liquid feed with the same levels of TS evaluated in the present study did not present differences in ruminal development, indicating similarity between the digestive and absorptive capacities of the animals. These results suggest that the provision of liquid feed with greater TS concentration during the preweaning period did not affect rumen development, therefore not compromising postweaning feed intake.…”

Section: Intake Performance and Growth Measurementssupporting

confidence: 64%

Effect of increasing amounts of milk replacer powder added to whole milk on postweaning performance, reproduction, glucose metabolism, and mammary fat pad in dairy heifers

Lage

Azevedo

Machado

et al. 2017

Self Cite

The aim of this study was to evaluate the effects of increasing the total solids (TS) content of liquid feed, by adding increasing amounts of milk replacer powder to whole milk, on age at puberty and postweaning performance, glucose metabolism, and mammary fat pad of dairy heifers. Crossbreed Holstein × Gyr heifers (n = 58) were distributed into 4 different treatments during the preweaning period. Treatments consisted of liquid feeds with TS content of 12.5 (actual TS = 13.5 ± 0.53%; n = 15), 15.0 (actual TS = 16.1 ± 0.03%; n = 15), 17.5 (actual TS = 18.2 ± 0.14%; n = 13), or 20.0% (actual TS = 20.4 ± 0.24%; n = 15), which were provided up to 59 d old. From 60 to 89 d old, the animals received the same starter offered during the preweaning period in addition to corn silage ad libitum starting at 70 d old. From 90 to 104 d old, the animals were adapted to a total mixed ration. At 105 d old, the animals were distributed in 4 paddocks equipped with electronic feed and water bins and were fed the same total mixed ration ad libitum. A period of adaptation to the electronic feed bins occurred from 105 to 119 d old. Feed and water intake and body weight and body frame development were assessed until puberty. Mammary gland evaluations were performed monthly by ultrasonography from 120 d of age until puberty onset. Puberty onset was determined as plasma progesterone concentration greater than 1 ng/mL in 2 consecutive samples collected 7 d apart. The date of puberty onset was recorded as the collection day of the first of these samples. A glucose tolerance test was performed at 280 d of age. The increased TS content of the liquid feed fed during the preweaning period did not affect dry matter intake, performance, age at puberty, glucose metabolism, or mammary gland fat pad at later stages of rearing process. Conversely, hip width and heart girth increased linearly up to 150 and 240 d of age, respectively, as a result of the increased TS concentration of the liquid feed during the preweaning period.

“…Ruminal passage kinetics (Azevedo et al, 2016), nutrient digestion, and VFA absorption (Conrad et al, 1956;Sutton et al, 1963;Khouri, 1969) are difficult to assess in young dairy calves. Overcoming technical complications related to assessment of ruminal passage kinetics, nutrient digestion, and VFA absorption are therefore essential steps toward improving our understanding of dairy calf nutrition.…”

Section: Technical Notementioning

confidence: 99%

Technical note: Infusion, sampling, and vacuum-assisted collection devices for use in ruminally cannulated calves

Yohe

Schramm

Parsons

et al. 2018

Calves can be ruminally cannulated at young ages, but equipment size limitations preclude use of an infusion and sampling device in these small animals. Likewise, a procedure to easily evacuate rumen contents in young calves has not been described. Overcoming these technical complications related to assessment of ruminal passage kinetics, nutrient digestion, and volatile fatty acid absorption would aid in future studies advancing our knowledge of dairy calf nutrition. The first objective was to design and fabricate 2 devices (one device for infusion and sampling, and another for vacuum-assisted collection) suitable for use in young ruminally cannulated dairy calves. The second objective was to test the utility of these tools when performing procedures commonly used in ruminant nutrition research. A single weaned 62-d-old ruminally cannulated calf was used to evaluate the ability to infuse a solution of LiCoEDTA and sample rumen contents through the cannula cap over a period of 2 h to assess the rumen liquid passage rate (procedure 1). The device was capable of infusing the LiCoEDTA and sampling the rumen fluid, as evidenced by the presence of elevated Co concentrations in the sampled rumen fluid. Using the fluid samples obtained, liquid passage rate within the calf was estimated to be 40.2% of ruminal fluid/h. The second procedure tested the vacuum-assisted collection device and consisted of evacuating and weighing the rumen contents, which is considered a key preparatory step in washed reticulorumen technique experiments that aim to measure nutrient absorption. In agreement with existing literature, evacuated rumen contents represented approximately 4% of the calf's body weight. In conclusion, custom-built devices for infusion, sampling, and vacuum-assisted collection were efficacious when tested in a 62-d-old ruminally cannulated calf fed a diet of 100% texturized starter (18% crude protein, as-fed). Fellow scientists may employ and further modify these techniques to suit their needs when assessing passage kinetics, nutrient digestion, and volatile fatty acid absorption in calves.