340 Relationship of Retained Energy in Lactating Beef Cows to Maintenance Energy Requirement and voluntary Feed Intake

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 192-192
Author(s):  
Emma A Briggs ◽  
Claire Anderson ◽  
Amanda Holder ◽  
Megan A Gross ◽  
David Lalman

Abstract This study’s objective was to determine the relationship between retained energy, lactation maintenance energy requirement (MER), and dry period voluntary feed intake (VOL) in beef cows. Twenty-four mature fall-calving Angus cows were used in an 82-d study during lactation to establish maintenance energy requirements followed by a voluntary feed intake study after weaning. During the lactation MER experiment, cows were housed in 2 drylot pens and limit-fed a mixed hay/concentrate diet (17.8% CP, 2.6 Mcal/kg ME, DM basis) individually once per d in a stall barn. Cows were adapted to the diet and feeding management for the first 16 d. Subsequently, cows were weighed and feed allowance adjusted at 14-d intervals to achieve BW and BCS stasis. Milk yield and composition were determined on d – 10, 49, and 77 using a milking machine. Retained energy was calculated as average daily maternal tissue energy change plus average daily milk energy yield. During the post-weaning VOL experiment, cows were provided ad libitum access to a grass hay diet for 41 d (8.15% CP, 1.8 Mcal/kg ME, DM basis) using five individual feed intake monitoring units (SmartFeed, C-Lock, Inc). Each one unit increase in metabolizable energy intake, kcal/kg BW0.75 was associated with a 0.86 ± 0.28 kcal/kg BW0.75 increase in total retained energy (P = 0.005). Using this partial efficiency coefficient, ME required for maintenance declined by 0.80 ± 0.11 kcal ME/kg BW0.75 for each additional kcal net energy retained/kg BW0.75 (P < 0.0001). There was no relationship between lactation-period retained energy and post-weaning VOL forage dry matter intake. The present study results contradict previous reports suggesting that maintenance requirements increase with increasing productivity.

2020 ◽  
Vol 4 (2) ◽  
pp. 1182-1195
Author(s):  
Claire E Andresen ◽  
Aksel W Wiseman ◽  
Adam McGee ◽  
Carla Goad ◽  
Andrew P Foote ◽  
...  

Abstract The objective of this study was to investigate the impacts of cow breed type and age on maintenance requirements, feed energy utilization, and voluntary forage intake. The main effect of breed type included Angus (ANG; n = 32) and Hereford × Angus (HA; n = 27) lactating cows. The main effect of age included 2- and 3-yr-old (YOUNG; n = 29) and 4- to 8-yr-old (MATURE; n = 30) cows. Within breed type and age class, cows were randomly assigned to 1 of 2 pens for a total of 8 pens, each housing 7 to 9 cow/calf pairs. To determine maintenance energy requirements, cows and calves were limit-fed for 105 d to body weight (BW) and body condition score (BCS) stasis. There were no differences between breeds in cow hip height, BW, average milk yield (P > 0.31), diet digestibility, or cow maintenance energy requirement (P = 0.54). Crossbred cows had greater BCS (P < 0.05) throughout the experiment. Efficiency of calf growth was not different between breeds when expressed as feed intake of the cow/calf pair nor as energy intake of the pair per unit of calf BW gain (P ≥ 0.31). Young cows produced less milk per day and per unit of BW0.75 (P < 0.01); however, there was no effect of cow age on maintenance energy requirement, diet digestibility, or efficiency of calf growth (P > 0.10). Subsequently, a 45-d experiment was conducted to determine voluntary low-quality forage intake. Cows were housed in dry-lot pens equipped with shade, windbreaks, and feed bunks with free-choice access to clean water and a chopped hay ration was provided ad libitum to determine forage intake. Daily forage intake was lower (P = 0.05) for HA compared with ANG (123 vs. 132 g/kg BW0.75, respectively) although there was no difference in BW. However, HA cows sustained greater BCS (P < 0.01). There was no difference (P = 0.60) in forage intake per unit of BW0.75 due to cow age. Results indicate similar calf growth efficiency among breed types although crossbred cows maintained greater body energy stores and consumed less low-quality forage during the voluntary intake experiment. These differences could not be attributed to lower maintenance energy requirements. Neither maintenance energy requirement nor calf growth efficiency was different between young and mature cows.


1989 ◽  
Vol 61 (1) ◽  
pp. 59-65 ◽  
Author(s):  
J. S. Chrisp ◽  
A. R. Sykes ◽  
N. D. Grace

1. Two groups of eight 6–7-month-old wether lambs were offered either a frozen ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) pasture or a ryegrass-white clover hay, containing 12.1 and 6.4 g calcium/ kg dry matter (DM) respectively. Within groups the amounts offered to individual sheep ranged from 0.5 to 2.0 times the estimated maintenance energy requirements.2. A single intravenous injection of 150 μCi 45Ca as CaCl2. 2H2O, and stable balances were used to determine absorption, faecal endogenous loss and balance of Ca.3. Faecal endogenous loss of Ca increased by 1.2 mg/kg body-weight (W) per d with each g/kg W per d increase in DM intake regardless of the diet. At any DM intake the mean faecal endogenous loss was 5.5 mg/kg W per d higher in the sheep offered the frozen herbage diet when compared with those on the hay diet. At any Ca intake the mean faecal endogenous loss was 6.9 mg/kg W higher in sheep offered the hay diet compared with those on the frozen herbage.4. At feeding levels of about 1.5–2 times the estimated maintenance energy requirement the observed faecal endogenous loss of Ca ranged from 35 to 50 mg/kg W per d, which is two- to threefold greater than the present estimate of the Agricultural Research Council (1980) of 16 mg/kg W per d.5. A simple model to explain the variation in faecal endogenous loss of Ca between the present study with young sheep and that with lactating ewes (Chrisp et al. 1989) also offered herbage diets is developed, which incorporates the concept of a true endogenous loss related to DM intake and a net endogenous loss reflecting the extent of re-absorption of Ca endogenous losses within the gastrointestinal tract.


2007 ◽  
Vol 137 (5) ◽  
pp. 1171-1175 ◽  
Author(s):  
Kwang S. Ko ◽  
Robert C. Backus ◽  
John R. Berg ◽  
Michael W. Lame ◽  
Quinton R. Rogers

1984 ◽  
Vol 24 (127) ◽  
pp. 507 ◽  
Author(s):  
RL Davies

In three experiments the effects of substituting field peas (Pisum sativum) for meat meal and/or fish meal in diets fed to growing and finishing pigs were studied. The inclusion of up to 28% peas in growing and finishing diets did not affect the digestible energy intake of pigs fed at up to 3.5 times their maintenance energy requirement. When peas comprised 53% of a diet fed to growing pigs, intake was depressed by 8%. With the exception of this diet, responses were consistent with changes in dietary lysine. It is concluded that, at up to about 40% of the diet, the lysine and energy value of field peas to growing and finishing pigs is consistent with analysed levels of these nutrients.


2020 ◽  
Vol 40 (2) ◽  
pp. 111-116
Author(s):  
Sang Uk Chung ◽  
◽  
Qi-Man Zhang ◽  
Se Young Jang ◽  
Yeong Sik Yun ◽  
...  

2016 ◽  
Vol 82 (15) ◽  
pp. 4570-4583 ◽  
Author(s):  
Corinna Rebnegger ◽  
Tim Vos ◽  
Alexandra B. Graf ◽  
Minoska Valli ◽  
Jack T. Pronk ◽  
...  

ABSTRACTThe yeastPichia pastorisis a widely used host for recombinant protein production. Understanding its physiology at extremely low growth rates is a first step in the direction of decoupling product formation from cellular growth and therefore of biotechnological relevance. Retentostat cultivation is an excellent tool for studying microbes at extremely low specific growth rates but has so far not been implemented forP. pastoris. Retentostat feeding regimes were based on the maintenance energy requirement (mS) and maximum biomass yield on glucose (YX/Smax) estimated from steady-state glucose-limited chemostat cultures. Aerobic retentostat cultivation enabled reproducible, smooth transitions from a specific growth rate (μ) of 0.025 h−1to near-zero specific growth rates (μ < 0.001 h−1). At these near-zero specific growth rates, viability remained at least 97%. The value ofmSat near-zero growth rates was 3.1 ± 0.1 mg glucose per g biomass and h, which was 3-fold lower than themSestimated from faster-growing chemostat cultures. This difference indicated thatP. pastorisreduces its maintenance energy requirement at extremely low μ, a phenomenon not previously observed in eukaryotes. Intracellular levels of glycogen and trehalose increased, while μ progressively declined during retentostat cultivation. Transcriptional reprogramming toward zero growth included the upregulation of many transcription factors as well as stress-related genes and the downregulation of cell cycle genes. This study underlines the relevance of comparative analysis of maintenance energy metabolism, which has an important impact on large-scale industrial processes.IMPORTANCEThe yeastPichia pastorisnaturally lives on trees and can utilize different carbon sources, among them glucose, glycerol, and methanol. In biotechnology, it is widely used for the production of recombinant proteins. For both the understanding of life in its natural habitat and optimized production processes, a better understanding of cell physiology at an extremely low growth rate would be of extraordinary value. Therefore, we have grownP. pastorisin a retentostat, which allows the cultivation of metabolically active cells even at zero growth. Here we reached doubling times as long as 38 days and found thatP. pastorisdecreases its maintenance energy demand 3-fold during very slow growth, which enables it to survive with a much lower substrate supply than baker's yeast.


Koedoe ◽  
1980 ◽  
Vol 23 (1) ◽  
Author(s):  
W Van Hoven

Fermentation experiments were performed on 36 buffaloes Syncems coffer. Body mass varied from 135-580 kg with an average for adults of 500 kg. Net mass of the reticulo-rumen content varied from 14-134 kg with a DM of 14,5. Fermentation rate was found to be 167,08 @ 13,53 fJimo\ gas^TpD/gDM/ hour and an adult of 500 kg produced 317,6 @ of methane per day from the rumen alone. An equivalent of 40,5 of the daily maintenance energy requirement is lost as methane. Caecal gas composition was found to be 60,63 @ 10,69 C02, 19,44 @ 8,0 CH4, 0,33 @ 0,26 H2 and 19,55 @ 11,43 N2. Ruminal gas composition: 73,85 @ 1,91 C02, 25,89 @ 1,79 CH4 and 0,029 @ 0,007 H2. Total VFA concentration, 12,06 @ 1,23 mmol/lOOml.


2020 ◽  
Vol 98 (10) ◽  
Author(s):  
Emily M Andreini ◽  
Sheyenne M Augenstein ◽  
Carrie S Fales ◽  
Roberto D Sainz ◽  
James W Oltjen

Abstract Comparing heat production after ad libitum (ADLIB) and restricted (RESTRICT) feeding periods may offer insight into how residual feed intake (RFI) groups change their energy requirements based on previous feeding levels. In this study, the authors sought to explain the efficiency changes of high- and low-RFI steers after feed restriction. To determine RFI classification, 56 Angus-cross steers with initial body weight (BW) of 350 ± 28.7 kg were individually housed, offered ad libitum access to a total mixed ration, and daily intakes were recorded for 56 d. RFI was defined as the residual of the regression of dry matter intake on mid-test BW0.75 and average daily gain. High- and low-RFI groups were defined as &gt;0.5 SD above or below the mean of zero, respectively. Fourteen steers from each high and low groups (n = 28) were selected for the subsequent 56-d RESTRICT period. During the RESTRICT period, intake was restricted to 75% of previous ad libitum intake on a BW0.75 basis, and all other conditions remained constant. After the RESTRICT period, both RFI groups had decreased maintenance energy requirements. However, the low-RFI group decreased maintenance energy requirements by 32% on a BW0.75 basis, more (P &lt; 0.05) than the high-RFI group decreased maintenance requirements (18%). Thus, the low-RFI steers remained more efficient after a period of feed restriction. We conclude that feed restriction decreases maintenance energy requirement in both high- and low-RFI groups that are restricted to the same degree.


Sign in / Sign up

Export Citation Format

Share Document