Effects of drinking water on feed intake, growth performance, health status, nutrient digestibility and composition of gut microbiota in young dairy calves

Thumbnail Image
Date
2019-01-01
Authors
Wickramasinghe, Handagala
Major Professor
Advisor
Ranga Appuhamy Jayasooriya
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
Authors
Research Projects
Organizational Units
Organizational Unit
Animal Science

The Department of Animal Science originally concerned itself with teaching the selection, breeding, feeding and care of livestock. Today it continues this study of the symbiotic relationship between animals and humans, with practical focuses on agribusiness, science, and animal management.

History
The Department of Animal Husbandry was established in 1898. The name of the department was changed to the Department of Animal Science in 1962. The Department of Poultry Science was merged into the department in 1971.

Historical Names

Journal Issue
Is Version Of
Versions
Series
Department
Abstract

There is a lack of data on water consumption and its role in dairy calves. The water requirements of dairy calves are negligibly defined. Producers pay little attention to whether calves consume enough drinking water (also called free water) as they consider water in milk or milk replacer would satisfy the total water requirement. A recent USDA survey revealed that dairy producers wait on average 17 d to first offer drinking water to newborn calves. Unlike milk or milk replacer directly shunted to the abomasum, drinking water first enters the rumen and then moves to the rest of the gastrointestinal tract. Therefore, drinking water presumably play a unique role in the development of gut and its microbiome in turn affecting nutrient intake, nutrient digestibility, and growth. The present study was conducted 1) to determine if newborn calves consume significant amount of free water separate from the water in milk, and 2) to examine the effects of offering drinking water since birth (W0) vs. 17 days later (W17) on starter intake, health status, growth, nutrient digestibility, and the composition of gut microbiota in young dairy calves. Thirty Holstein heifer calves were randomly assigned to W0 or W17 (n = 15). Calves had free access to drinking water and a starter ration, and bottle-fed with pasteurized waste milk until weaning at 49 d of age. Fresh fecal samples were collected directly from the rectum at 14, 42, and 70 d of age. The DNA were extracted from fecal samples and sequenced using 16S rRNA gene-amplicon sequencing on an Illumina MiSeq system. The sequences were clustered into operational taxonomic units with a 99% similarity threshold. Total fecal output of individual calves was measured over two consecutive days to determine apparent total-tract digestibility (ATTD) of nutrients three weeks post-weaning. Newborn calves consumed a significant amount (0.75±0.05 kg/d) water separate from the water in milk during the first 16 d. Once offered, W17 drank 59% more free water than W0 during the rest of the pre-weaning period. Starter intake of W0 and W17 was similar, but W0 consumed 0.285 kg/d more milk and tended to achieve greater BW and heart girth (HG) compared to W17 during the pre-weaning period. Offering water from birth versus offering it later did not affect the number of days with diarrhea, intensity of diarrhea, and blood hematocrit values. Despite a similar starter intake, W0 had greater hip height, body length, ATTD of ADF and NDF, and gain: feed ratio than W17 post-weaning. At 14 d of age, feces from W0 had a greater number of bacterial species (5908 vs. 4698, P = 0.033) and species richness (Chao1 index, P = 0.042) than feces from W17. The number of bacterial species, and Chao1 index increased with age (P < 0.001) and became similar between W0 and W17 at 42 d of age. At 42 d of age, the abundance of Faecalibacterium prausnitzii, and Bifidobacterium breve previously shown to improve gut health and growth were greater in W0 than W17 (P < 0.040). Overall, the present study highlighted that offering drinking water since birth has a potential to improve growth, nutrient digestibility, feed conversion efficiency, and the abundance of beneficial bacterial communities in the gut of young dairy heifer calves.

Comments
Description
Keywords
Citation
DOI
Source
Copyright
Thu Aug 01 00:00:00 UTC 2019