نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه علوم دامی، دانشکدگان کشاورزی و منابع طبیعی، دانشگاه تهران، کرج، ایران
2 گروه علوم دامی- دانشکدگان کشاورزی و منابع طبیعی - دانشگاه تهران - کرج- ایران
3 گروه علوم دامی - دانشکده کشاورزی و منابع طبیعی - دانشگاه تهران-کرج - ایران
4 شرکت ارس دام آرشام ، پلدشت، آذربایجان غربی، ایران.
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
The aim of this study was to evaluate the effect of feeding different levels of lipidol (containing active lysophospholipids and lecithin) as starter feed additive on performance of Holstein calves. Forty colostrum fed calves from 3 days of age were randomly assigned to a completely randomized design on d 3 of age. Treatments included starter feed without lipidol (STL0) and 0.05% (STL0.5), 0.1% (STL1) and 0.2% (STL2) lipidol as DM basis. All calves were housed individually and had free access to starter feed and fresh water throughout the study. Dry matter intake from starter diet was greater in STL2 group than the other groups (p = 0.04) throughout the study. Fat digestibility increased linearly as the lipidol concentration increased, with significant difference between STL2 and control groups ( P < 0.05). Average daily gain (ADG) tended to be significant difference in calves fed STL0.5 and STL2 diet (p= 0.08 ) during the early post weaning period. Glucose concentration tended to be increased in STL2 calves relative to other counterparts (p = 0.08). Also, a greater concentration of total protein and albumin was found for STL2 calves on d 28. Control calves had elevated levels of NEFA in the plasma samples than those fed lipidol additive on d 60 of study, indicating the effectiveness of this additive on fat metabolism and energy. Overall, it can be concluded that supplementing pre-weaned calves starter diet with 0.2 % lipidol as DM may improve the performance of calves during pre and early post-weaning periods.
کلیدواژه‌ها [English]
Extended Abstract
Introduction
Nutritional strategies and feeding management of calves during the pre-weaning period may affect their lifetime performance and future productivity of dairy industry. Contradictory results have been reported for the use of fats in the diet of suckling calves, which indicates the existence of several factors affecting the response of calves to fat supplements. The main purpose of fat supplementation in a starter diet is to serve as a concentrated source of energy and improve calf performance; but, the amount of fat that is recommended in starter feed is less than 5 percent of DM basis according to NASEM 2021. Emulsifiers are amphiphilic substances with capable of mixing lipids and water. Lysophospholipids (LPLs) are glycerophospholipids that only one of the hydroxyl groups of the glycerol backbone is acylated and the other acyl chain is absent. The potential effects of LPLs specially lysolecithins, have been studied previously in nonruminant animals and their positive effects on nutrients digestion and absorption is reported. We hypothesized that supplementing starter diet with active LPLs could improve fat digestion and growth performance of pre-weaned calves.
Materials and Methods
The present study was conducted in a large dairy farm with 1,500 milking cows located in the south-east of Varamin, Tehran, Iran (Abbasi Agriculture and Animal Husbandry Complex) from April to July 2021. In this experiment, a total of forty colostrum fed Holstein calves (24 female; 16 male) with 3-d-old and 40.15 ± 7 kg of initial BW were tested in a completely randomized design with four experimental diets and 10 replications per treatment. Treatments included starter feed without lipidol (STL0) and 0.05% (STL0.5), 0.1% (STL1) and 0.2% (STL2) lipidol as DM basis. All the 4 diets were isocaloric and isonitrogenous and the basal starter diet was adjusted based on the dietary recommendations of dairy cows (NRC, 2001). Starter feed refusals were collected and recorded daily at 1630 h and fresh starter fed 1700 h throughout the experiment. Measurements of BW were taken at every other week using an electronic balance which was calibrated monthly. Faeces and feed samples were taken at the end of the experiment for 3 consecutive days to measure the digestibility of dry matter, ADF and Eter extract (EE) using the acid-insoluble ash method. First, Per animal fecal samples were pooled and 100 g/ head was frozen in plastic bags at – 20°C until subsequent analysis. All collected data were analyzed using SAS software version 9 and GLM and MIXED procedures.
Results and discussion
The present study evaluated the effect of feeding different levels of lipidol as starter feed additive on growth, health, nutrient digestibility, and blood and ruminal parameters in Holstein young calves. To our best knowledge, there are few studies examined LPLs as a feed additive in dairy calves. Thus, because of a few information about LPL in calves, studies with non ruminant animals and mature ruminant that fed LPL or lecithin as feed additive are used to discuss our results. The results showed that dry matter intake from starter was higher in STL2 group than the other groups (p = 0.04) throughout experimental period. Apparent digestibility of dry matter was higher for calves fed STL2 than other groups. Also, Lipidol consumption linearly increased fat digestibility (P = 0.042). At early post-weaning, the highest daily weight gain was in calves fed STL0.5 and STL2 diet (p = 0.08). There was no significant difference between health indicators (except eye score) and ruminal parameters. Glucose concentration tended to be increase significantly in STL2 relative to other treatments (p = 0.08). Also, the concentration of total protein and albumin in STL2 was higher than other groups on d 28. Control calves had higher concentration of NEFA in the plasma samples than those fed lipidol additive on d 60 of study, indicating the effectiveness of this additive on fat metabolism. According to the results of the present study, it is concluded that consumption of 0.2 % of lipidol as DM basis of starter feed can increase feed intake, increase the apparent digestibility of dry matter and dietary crude fat, improve growth, increase glucose concentration and decrease NEFA concentration in the blood plasma of calves. According to the results of the present study, the effects of consuming the studied levels of lipidol additive (0.5, 1 and 2 g / kg of starter feed) are not linear in other traits, except for the crude fat digestibility in the diet. Therefore, higher levels of this additive and especially in diets containing more crude fat need to be investigated.
Mehdi Dehghan banadaky: Conceptualization, Validation, Supervision, Writing - Review & Editing, Project administration,
Sadegh Farzi: Methodology, Software, Formal analysis, Investigation, Writing - Original Draft
Kamran rezayazdi: Conceptualization, Validation, Supervision
Mehdi Ganjkhanlou: Methodology, Validation.
Masoud Alimirzaei: Data analysis, Project administration.
The data supporting reported results are collected and used from published articles, to them we have referred in the manuscript.
The authors would like to thank Pathway Company (South Korea) for financial support. Also thank Abbasi Dairy farm for supporting present study.
The study was approved by the Ethics Committee of the University of ABCD (Ethical code: IR.UT.RES.). The authors avoided data fabrication, falsification, plagiarism, and misconduct.
The author declares no conflict of interest.
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