1
MINISTRY OF EDUCATIONAND TRANING / MINISTRY OF AGRICULTURE
& RURAL DEVELOPMENT
NATIONAL INSTITUTE OFANIMAL SCIENCE
============
NGO DINH TAN
DETERMINATION OF METABOLIZABLE ENERGY AND NET ENERGY REQUIREMENTS FOR MAINTAINANCEAND MILK PRODUCTION OF VIETNAM HOLSTEIN CATTLE
Speciality: Animal Feeds and Nutrition
ID: 62-62-01-07
SUMMARY OF PHD THESIS FOR DOCTOR OF SIENCE IN AGRICULTURE
HANOI,2017
The thesis was completed at: NATIONAL INSTITUTE OF
ANIMAL SCIENCE
Scientific supervisors:
- Prof.Dr. Vu Chi Cuong
- Dr. Pham Kim Cuong
Opponent 1: ......
Opponent 2: ......
Opponent 3: ......
The thesis will be defended at the Thesis Examination Committee (Institute Level) in the National Institute of Animal Sciences.
At[Time][Date][Month][Year]
Thesis can be found at:
- National Library
- Library, National Institute of Animal Science
CHAPTER I: INTRODUCTION
1.Justification
Locally born crossbred dairy cattle of eighty seven point five percentages of HF with a highmilk potentialseem to have a good adaptation under domestic conditions. Therefore, when application of the nutrient standardsfrom other countries for feeding these dairy cows, results were not stable. Vu Chi Cuong et al. (2009, 2011a, 2011b, 2012) was determined of MEm and NEm requirement for calf and crossbred dairy cows with 75% HF using the respirationchamber.Combination of the respirationchamber and feeding trials for determining the energy requirement for maintain ace and milk productionof HV (Holstein Vietnam) dairy cows in Vietnam condition should be more accurate. The energy value of animal feeds determined in the respirationchamberused for correction of the energy values of animal feeds estimated by equations.
To ensure that ration formulation for HV dairy cows will be more and more accurate, the study, titled “Determination of the metabolizableenergy and net energy requirements for maintenance and milk productionof Vietnam Holstein cattle” was undertaken
2. The objectives
- Determiningthe MEm and NEm requirement for maintenance of HV dairy cow at 3 levels of live weight: 400, 500, 600 kg.
- Determining the MEl and NEl requirement for lactating HV cow at high milk production (≥4500 l/cow/lactation).
- Recorrecting energy requirement values for maintenance and milk production in practical conditions.
3. The scientific and practical significance of thesis
The results of thesis contributed tothe database on MEm, MEl and NEl for HV dairy cows in Vietnam. These energy values could be used for correction of the energy values of animal feeds estimated by equations. The results of this thesis willhelp to formulate rations for HV dairy cows more accurate and to reduce feed cost in dairy production..
The results of this thesis could be considered as a reference for policy makers, researchers, lecturers and agricultural students in studies, teaching and training.
The results of this thesis could also be used as a reference for dairy farm managers in a ration formulation.
4. New contributions of thesis
- This thesis was determined the ME, NE requirement for maintenance and milk production of HV dairy cattle at 400, 500 and 600 kg of live weight.
- This thesis also was determined the ME and NE for maintenance and milk production of HV cows.
- This thesis was determined the ME and NE requirement for maintenance and milk production of HV cows in practical conditions.
CHAPTER II: LITERATURE REVIEW
1.1. Vietnam dairy development review
The population of crossbred dairy cows with 87.5% HF is increasing.These cows was born in Vietnam and were reared in domestic conditions therefore their adaptation and genetic makeup were differfrom imported dairy cows. Recently, agricultural scientists and officers had called this group of dairy cows as Vietnam Holstein (HV).
1.2. Dairy energy requirementreview
Energy is an important role in animal body, it participates in many body activities, including the biochemical process, nervous and translation action or cell membrane transport activities…(Blaxter, 1989). The animal life needed a minimum amount of energy for maintenance, on the other hand, the energy also required for production activities such as meat, milk production … The amount of energy required relied on physiology and environment condition (Ferrell và Oltjen, 2008). Determination of the energy amount needed is most important work for ration formulation of animals.
1.3. Several Energy Systems for ruminants
The energy value in ruminant feeds was interesting paid attention by scientistsand also continuously done for collecting more data for practical use. The AFRC publication in 1993 was one edited version of ME system used in England. The edited version was based on research works on dairy cattle of Van Es in Lelytat, Holland, Flatt, More and Tyrrell in USDA (USA Ministry of Agriculture in Beltsvilla) (Van Es, 1978). Whereas several NE system was developed in Europe and North America (Van Es, 1978, INRA, 1978 and NRC, 1978). In Van Es (1978) system, the NEl value was used. In America (1978), NRC also used the NEl and calculation of NEl from ME of feeds. In France and Germany NE system was also used as well. Recently, the NElhas been used more in Germany, France, Holland, Switzerland, Denmark, Ireland and North America. The differences of ME and NE systems was the effectiveness of energy used.
1.4. The energy requirement evaluation in ruminant
The recent research works showed that the MEm of cattle was higher and was influenced by the fiber levels in the rations and grazing activity. The MEm and level of body protein was stronglyrelated. However, Kl value was rather stable and did not influenced by rations and genetic makeup of cattle. The energy values for each body weight unit was changed and varied and depending on the body condition score and phases of lactation.
1.5. The world and domestic energy requirement research for dairy cattle
In recent time, research works had showed that the energy requirements for production published by different systemswas not equal. Some of the results published by Yan et al. (2003) in Ireland showed that the energy requirement published by Van Es (1978); AFRC (1990, 1993) and NRC (2001)was lower than that in practical conditions and that if using the AFRC (1990, 1993) feeding standards for dairy cows, more than 5% of energy needed to be added in calculation.. The problem was that application of the foreign energy standard to domestic crossbred dairy cows may lead to unbalanced energy rations (sufficient or insufficient). Therefore, is was necessary to consider to use foreign feeding standards such as NRC or others in ration formulation for dairy cattle in Vietnam.
CHAPTERII:MATERIALS AND METHODS
2.1. Materials
- The animals: The dry and non-pregnant3 to 5 year old HV cows at 400, 500 and 600 kg of live weight; and.lactating HV dairy cows with ≥4,500 kg of milk per lactationwere used in this study.
- Feeds: rice straw, Napier grass, natural grass, alfalfa hay, barley, corn ground, rice bran, soybean meal, concentrate, urea, palm meal.
- Respiration chamber, dairy farms.
2.2. Experimental location and period
2.2.1. Experimental location
Animal Experimentation and Conservation Center, Nutrition and Animal Feed Department – Institute of Animal Science, Ho Chi Minh City Dairy Company, Dairy farm in Dong Thanh Commune, Hoc Mon District, Ho Chi Minh City.
2.2.2. Experiment period: From 2011to 2014.
2.3. Research contents
Thesis contained three following studies 1, 2, 3.
2.3.1.Estimation of the MEm and NEm requirements for Vietnam Holstein (>87,5% HF) at 400, 500 and 600 kg of live weight.
2.3.2. Estimation of the MEl and NEl requirements for Vietnam Holstein (>87,5% HF) with ≥ 4500 kg milk per lactation.
2.3.3. Evaluation of energy requirements for maintenance and milk production estimated on Vietnam Holstein (HV) cows under practical conditions.
2.4. Research methods
2.4.1. Estimation of the MEm and NEm requirements for Vietnam Holstein (>87,5% HF) at 400, 500 and 600 kg of liveweight.
The experiment was conducted in three periods, the third period was the period for determining the requirement for maintenance. In each live weight levels five HV dairy cows, they was measured FHP for 4 continuously days andmean of these measurements was requirement for maintenance of each live weight level.
Period 1: Digestible trial in metabolism crates
The in vivo digestible trial was conducted according to procedures of the in vivo digestibility experiment with the total collection of feces and urine of Burn et al. (1994) and Cochran and Galyean (1994).
Period 2: Digestible trial in respiration chamber.
The temperate and humidity were controlled at 24 – 260C and 45 – 50%. The O2consumed methane and carbonic dioxide emissions were measured continuously in 2 day in respiration chambers by the automatic sensor system. The total heat production(HP) was calculated according to the equation of Brouwer (1965). All animal were offer feed and sampled similar to that in period 1 and live weightof animals was also measured..
Period 3: Fasting metabolism trialin respiration chamber
In this period animals was fasting with water free access for 4 days and the fifth day fasting metabolism was measured. The O2 consumed methane and carbonic dioxide emissions were measured continuously in 2 day in respiration chambers by the automatic sensor system.The urine excreted and live weights of cattle were also measured every day. The FHP (Fasting heat production) calculated according to the equation of Brouwer (1965) was NEm of experimental cows. The HP value measured in period 2 combined with FHP value from period 3 was used to determine the coefficient km (km = NEm/MEm).
For all two periods (1 and 2) and before fasting in period 3, Napier grass, rice straw, corn meal, rice bran, soybean meal, concentrate were mixed in a TMR ration and offered twice a day at 8 AM and 16 PM. daily. The animal was offered limited feed to make sure that ADG of animals was the smallest or equaled to zero.
The DM, CP, Ash, feces and urine were measured according to the TCVN 4326:2001; TCVN 4328:2007; TCVN 4327:2007standards. NDF and ADF were measured according to AOAC 973.18 (2006). The GE was estimated using Bomb Calorimeter and the urine sample was burned using paraffin flame retardant. The live weight, feed offered and feed refused were weight and recorded daily for measuring the voluntary feed intake. The in vivo digestibility was measured according to the total collection urine and feces method; the energy for each kg methane was calculated according to the CRC, 2010 Book.
The HP in period 2 and FHP in period 3 were calculated according tho the equation of Brouwer (1965). The coefficient of ME utilisation for mainternance purpurse was calculated according to the fomular: km = FHP/HP.
The NEm requirement of dry nonpregnant dairy cows equalled to FHP (Platt et al., 1965). Accordingg to NRC (2001), NEm for dairy cow in pen on the farm needed to be added more 10% to FHP: NEm = FHP + (0,1 FHP)
The data were analyzed by ANOVA with in Minitab sofware verson 14.0. T-student test was used to campare two means. The regression technique was used to establish relashionships of measured parametters .
2.4.2. Estimation of the MEl and NEl requirements for Vietnam Holstein (>87,5% HF) with ≥ 4500 kg milk per lactation.
Fifty HV cows with ≥ 4500 kg of milk per lactation in early, middle and late lactation from 6 dairy farms were used in this experiment. The feeds for animals included Napier grass, rice straw, nature grass, barley, casava chip residue, rice bran, soybean meal and concentrate. Rations were formulated according to Vu Chi Cuong et al. (2012) for sufficient MEl and the crude protein according to NRC (2001) standard. The mixed concentrate was offered to animals before milking twice a day.
The feed offered and feed refused were weighed and recorded daily; the milk production and chemical composition of milk, live weight change and day in milk during lactation also measured and recorded. The chemical composition of feeds and nutrient values of feeds, energy values were measured similar to the first study.
The fat-corrected milkwas calculated according the the Gaines (1928) formular. The total MEI (MJ/day) was calculated as followsMEI = ME1 + ME2 + ME3 + … + MEx (ME1-x (MJ), where ME was ME value of feed X1-x; DM1-xwas dry matter intake of feed X1-x. The MEm was calculated according to Vu Chi Cuong et al. (2012); The MEpfor early pregnancy was estimated according to Vu Duy Giang et al. (2008) and the MEp for 4 month of late pregnancywas estimated according toMore (2005). The MEl (MJ/kg FCM) was calculated as follows:
MEl = / MEI – (MEm + MEp + MEg)Fat-corrected milk (kg)
The NEl was determined by two methods: using Bomb calorimeter and by equation of Tyrrell and Reid (1965). NEl values measured by two methods then were usedto establish their relationship with the regression technique.
Kl was calculated as follows: MEI(0) = MEI - MEg (MEI(0)), where MEI(0)was total ME offered to animal when the live weightwas unchanged. MEg was total ME for live weight change. When MEI(0), was determined and total ME in milk/day, these values were used to establish thelinear regression equation to determine kl(Agnew and Yan, 2000) in the form y = ax + b (y = NEl; x = MEI(0)and a was conversion factor: ME to milk energy (kl).
The data were analyzed by ANOVA with Minitab software, verson 16.0. Differences between two mean were determined by Tukey. The linear regressions equations were conducted with Minitab regression technique.
2.4.3. Evaluation of energy requirements for maintenance and milk production estimated on Vietnam Holstein (HV) cows under practical conditions.
Twenty HV milking cows with a milk yield of 4500 kg milk per lactation, at 2 – 3 months of pregnancykept individually in pens were used in this experiment. They were randomly allocated according to the Complete Randomized Design.Experimental factor in this experiment was the nutrition level with 4 levels of nutrition based on the results of energy requirements for maintenance and milk production estimated in studies 1 and 2. Five animals were allocated to each level of nutrition and the experiment was lasted for 60 day. The experimental rations were formulated according to the INRA (1989) and NRC (2001) standard, the control ration was the ration used in farm. The TMR was used in this experiment containing Napier grass, Alfalfa hay, palm meal, barley and concentrate. The ME and CP content in each kg (DM basis) of TMR was 10.68 MJ and 171,27 g, respectively.
During the experiment period the live weight, feed offered, feed refused, feces, urine, nutrition digestibility and ME intake, ME in feces and urine, milk energy, daily milk production and milk chemical composition, live weight change were analyzed. The feed chemical composition and nutrition values were also measured and analyzed as described in study 1 and 2.
The FCM, total daily MEI…were calculated and analyzed as described in study 1 and 2.
The data were analyzed by ANOVA with in Minitab sofware verson 14.0. Tukey test was used to campare two means. The regression technique was used to establish relashionships of measured parametters .
CHAPTERIII: RESULTS AND DISCUSTION
3.1. Estimation of the MEm and NEm requirements for Vietnam Holstein (>87,5% HF) at 400, 500 and 600 kg of liveweight.
3.1.1. Period 1: The feed intake and in vivo digestibility
Table 3.1. Feed intake and in vivo digestibility
Items / HV 400 kg / HV 500 / HV 600 / PMean ± SD / Mean ± SD / Mean ± SD
DMI (kg/100 kg LW) / 1.65a ± 0.4 / 1.42b ± 0.4 / 1.35c ± 0.2 / <0.001
OMI (kg/100 kg LW) / 1.43a ± 0.4 / 1.28b ± 0.4 / 1.22c ± 0.2 / <0.001
DMD (%) / 65.6a ± 2.1 / 60.2b ± 3.7 / 57.0b± 1.3 / 0.001
OMD (%) / 67.1a ± 2.1 / 62.3b ± 3.5 / 58.4b± 1.2 / <0.001
CPD (%) / 56.9 ± 6.5 / 56.2 ± 2.9 / 55.9 ± 1.5 / 0.383
NDFD (%) / 63.9a ± 3.7 / 56.9b ± 3.6 / 51.6c ± 1.5 / <0.001
ADFD (%) / 65.8a ± 4.0 / 54.7b ± 4.9 / 51.7c ± 2.7 / <0.001
a, b, c Mean in the same row with different superscripts differed (P<0.05); DMI: dry matter intake, OMI: organic matter intake; DMD: DM digestibility; OMD: OM digestibility; CPD: crude protein digestibility; NDFD: NDF digestibility; ADFD: ADF digestibility.
The results showed that the DM and OM intake per 100 kg of liveweight were significantly different and decreased from animals of 400 kg to 500 and 600 kg (P<0.05). The digestibility of DM, OM and ADF was significantly different between the group of animals of 400 kg and the groups of animals of 500 and 600 kg (P<0.05). However, No differences in digestibility of DM, OM and ADF was found fro groups of animals of 500 and 600 kg. The digestibility in general tended to be diclined when liveweight increased, while the crude protein digestibility was similar among groups (P>0.05).
3.1.2. Period 2:O2 consumed, CO2 and CH4emitted, dailyof total heat production, MEm
Table 3.2. O2 consumed, CO2 and CH4emitted, daily of total heat production, MEm
Items / HV 400 kg / HV 500 kg / HV 600 kg / PMean ± SD / Mean ± SD / Mean ± SD
Liveweight (kg) / 397.2 ± 10.0 / 491.7 ± 20.1 / 592.1 ± 12.7
W0,75 (kg) / 89.0 ± 1.7 / 104.4 ± 3.2 / 120.0 ± 1.9
O2 (l/day) / 2294.9c±123.1 / 2624.5b± 98.0 / 2915.9a±117.0 / <0.001
CO2(l/day) / 2125b ± 128.5 / 2158.0b±209.0 / 2451.1a±221.8 / 0.001
CH4(l/day) / 165.7c ± 15.8 / 194.9b ± 29.8 / 247.7a ± 22.9 / <0.001
KJ from CH4/kg LW / 0.017471 / 0.0166 / 0.017526
HP (KJ/kgW0,75) / 478.4a ± 12.9 / 451.3b ± 6.4 / 443.0b ± 10.2 / <0.001
MEm (KJ/kgW0,75) / 526.2a ± 14.1 / 496.4b ± 7.1 / 487.3b ± 11.2 / <0.001
a, b, c Mean in the same row with different superscripts differed (P<0.05).
Results showed that in the situation of less movement and feeding at the mainternace level, O2 consumed, CO2and CH4 emited increased with increased liveweight (P<0.05). HP and MEm requirement of dry and non-pregnant HV dairy cows of 400 kg were significantly higher than that of similar cows of500 and 600 kg (P<0.05). No differences in HP and MEm of animals of 500 and 600 kg was found(P>0.05). The results of ANOVA showed that there were only the linear and quadric relationships between MEm and liveweight.
The modeling results in figure 3.1 and 3.2 showed that with a higher coefficient of determination, the quadric equation was best described relationship between MEm and live weightof cows.
Figure 3.1.Linear relationship between MEmandLWY (MEm KJ/kgW0.75) = 600.0 – 1.1915 ×LW (kg) P<0.001 / Figure 3.2. Quadratic relationship between MEmand LWY (MEmKJ/kgW.,75) = 817.5 – 1.093 ×LW kg + 0,000910 x (LW kg)2The MEm of HV cows calculated in these studies ranged from 487.6 – 526.2 KJ/kgW0.75. These results wereslightly lower than that reported by Vu Chi Cuong et al. (2010a) in dairy crossbred heifers with 75% HF (593.5 KJ/kgW0.75) and were also lower than that’s reported by INRA (1989) (666.4 KJ/kgW0.75).
However, these results of MEmrequirement for HV cows(487.6 to 526.2 KJ/kgW0.75)were similarly with the results on some research work (570 KJ/kgW0.75 and ranged from 490 to 670 KJ MEm/kgW0.75) (Table 3.3).