Response of lactating goats to low phosphorus intake 2. Nitrogen transfer from rumen ammonia to rumen microbes and proportion of milk protein derived from microbial amino acids

1988 ◽  
Vol 111 (2) ◽  
pp. 265-271 ◽  
Author(s):  
A. Petri ◽  
H. Müschen ◽  
G. Breves ◽  
O. Richter ◽  
E. Pfeffer
Keyword(s):  
Milk Protein ◽  
Rumen Fluid ◽  
Nitrogen Transfer ◽  
Dairy Goats ◽  
P Deficiency ◽  
Rumen Microbes ◽  
Lactating Goats ◽  
Low Phosphorus ◽  
Outflow Rate ◽  
Cr Concentration

SummaryFive rumen-cannulated dairy goats were fed diets supplying 2·8 g P/day plus 1·4 g P/kg milk (adequate P) for weeks 1–6 of lactation. Two goats then continued to receive this adequate P supply while three goats were fed deficient diets supplying only 0·8 g P/day plus 0·4 g P/kg milk. Solutions containing CrEDTA and (15NH4)2SO4 were infused into the rumen continuously for 96 h during weeks 5–6 and 11–12, respectively. At intervals following the intraruminal infusion, 15N enrichments of rumen ammonia-N, rumen bacteria-N and milk protein-N were determined. Cr concentration was measured in particle-free rumen fluid.P deficiency did not significantly affect rumen fluid kinetics. It caused a significant increase in pH and reduced the size of the rumen ammonia pool and its outflow rate. Digestibility of organic matter as well as efficiency of microbial protein synthesis were decreased significantly and thus net microbial yield was reduced from 34·1 to 13·7 g N/day. The transfer of N of microbial origin to milk protein decreased from 5·3 to 2·7 g/day, whereas secretion of N in milk protein not originating from rumen microbes remained unchanged at 5·6–5·8 g/day.

Response of lactating goats to low phosphorus intake 1. Milk yield and faecal excretion of P and Ca

1988 ◽  
Vol 111 (2) ◽  
pp. 255-263 ◽  
Author(s):  
H. Müschen ◽  
A. Petri ◽  
G. Breves ◽  
E. Pfeffer
Keyword(s):  
Milk Yield ◽  
Rumen Fluid ◽  
Live Weight ◽  
Faecal Excretion ◽  
P Deficiency ◽  
Lactating Goats ◽  
Low Phosphorus ◽  
Group 3 ◽  
Group 2 ◽  
Phosphorus Intake

SummaryIn weeks 1–6 of lactation, 11 goats were fed diets adequate in phosphorus content, supplying a basal intake of 2·8 g P/day plus 1·4 g P/kg milk produced. In group 1 (three goats), this scheme was continued until week 16. In group 2 (four goats), P supply was changed from an adequate one to a reduced amount by restricting the variable intake to 1·0 g P/kg milk during weeks 7–16 and the basal intake to 0·8 g P/day during weeks 12–16. In group 3 (four goats), P deficiency was caused during weeks 7–11 by a basal intake of 0·8 g P/day plus only 0·4 g P/kg milk. During weeks 12–16 these goats received the same supply of P provided in weeks 1–6.Milk yield was depressed in group 3, but not in group 2. Composition of milk was not affected by P intake in either group. Digestibility of organic matter was reduced from 0·73 to 0·64 by P deficiency treatment. Reduction of faecal P excretion in group 2 appeared to enable P homoeostasis even at the reduced level of P intake. The amounts of P and Ca secreted in milk during P deficiency in group 3 clearly exceeded the corresponding net absorptions. During this period, daily faecal P excretion was reduced to 17 mg/kg live weight. P concentrations in blood plasma, saliva and particle-free rumen fluid were also drastically reduced. Faecal excretion of P increased after the animals returned to the diet supplying adequate P. The increase occurred before the pre-depletion P status had been restored.

Peptide utilisation by the mammary gland of lactating goats.

1994 ◽  
Vol 1994 ◽  
pp. 26-26
Author(s):  
F.R.C. Backwellf ◽  
B J. Bequettet ◽  
J.A. Metcalf ◽  
D. Wray-Cahen ◽  
L. Crompton ◽  
...  
Keyword(s):  
Mammary Gland ◽  
Dairy Cows ◽  
Milk Protein ◽  
Dairy Goats ◽  
Small Peptides ◽  
Lactating Goats ◽  
Uptake Studies ◽  
Milk Casein ◽  
Casein Synthesis

During lactation the ruminant mammary gland removes relatively large quantities of circulating amino acids (AA) to meet the requirements for milk protein synthesis but arterio-venous uptake studies in dairy cows (1) have indicated that the uptake of certain AA may be insufficient to account for their output as milk protein. The apparent deficit may be accounted for by the use of AA supplied to the gland as small peptides or proteins. A dual-labelled tracer approach involving infusion of [13C]-labelled peptides into the external pudic artery which supplies blood directly to the mammary gland demonstrated that dipeptide-bound AA can be utilised as direct precursors for milk casein synthesis in lactating dairy goats (2). However, previous studies using vascular infusion of [13C]-labelled free AA (3) have provided equivocal data on involvement of non-labelled extra-mammary derived peptides/proteinsin vivoin the biosynthesis of milk protein.

scholarly journals High Rumen-Degradable Starch Diet Promotes Hepatic Lipolysis and Disrupts Enterohepatic Circulation of Bile Acids in Dairy Goats

2020 ◽  
Vol 150 (10) ◽  
pp. 2755-2763
Author(s):  
Jing Shen ◽  
Xiaoying Han ◽  
Lixin Zheng ◽  
Shimin Liu ◽  
Chunjia Jin ◽  
...  
Keyword(s):  
Protein Expression ◽  
Bile Acids ◽  
Milk Fat ◽  
Enterohepatic Circulation ◽  
Rumen Fluid ◽  
Liver Protein ◽  
Dairy Goats ◽  
Linear Discriminant ◽  
Lactating Goats ◽  
Carnitine Palmitoyltransferase 1

ABSTRACT Background High rumen-degradable starch (RDS) diets decrease milk fat. The increase of LPS in plasma associated with increased RDS impairs liver function, immune response and lipid metabolism, which depress the precursors for milk fat. Objective This study investigated the mechanism of depression of milk fat precursors in the liver and small intestine of dairy goats fed different RDS diets. Method Eighteen Guanzhong lactating goats (second lactation, 45.8 ± 1.54 kg) and 6 ruminally cannulated dairy goats (aged 2–3 y, 54.0 ± 2.40 kg) were fed 3 different diets with low dietary RDS concentrations of 20.52% (LRDS), medium RDS of 22.15% (MRDS), and high RDS of 24.88% (HRDS) for 36 and 21 d, respectively, in experiments 1 and 2. The liver metabolites and jejunal microbiota in experiment 1 and LPS concentrations in rumen fluid and plasma in experiment 2 were measured. One-way ANOVA was used to analyze the biochemical parameters and mRNA or protein expression. The MIXED procedure was used to analyze LPS concentrations. Results In experiment 1, the HRDS diet showed increased activity of alkaline phosphatase (27.4 to 41.4 U/L) in plasma (P < 0.05) compared with LRDS treatment. The HRDS diet significantly increased the hepatic concentrations of l-carnitine (129%), l-palmitoylcarnitine (306%), taurochenodeoxycholate (856%), and taurodeoxycholic acid (588%) in liver (variable importance in the projection > 1, P < 0.10) compared with the LRDS treatment. Goats fed the HRDS diet had 33.6% greater liver protein expression of carnitine palmitoyltransferase-1 (P < 0.05), and greater relative abundance of Firmicutes and Ruminococcus 2 in the jejunal content (linear discriminant analysis > 2.0, P < 0.05) than did goats fed LRDS diet. In experiment 2, goats fed the HRDS diet had greater LPS concentrations in rumen fluid (7.57 to 13.6 kEU/mL) and plasma (0.037 to 0.179 EU/mL) (P < 0.05) than did goats fed LRDS diet. Conclusions Feeding the HRDS diet promoted hepatic lipid β-oxidation and disrupted phospholipid and bile acids metabolisms in liver, thereby reducing the supply of lipogenic precursors to the mammary gland in dairy goats.

Effect of intravenous histidine or histidine peptide infusion on milk protein yield in lactating goats with an induced histidine deficiency

1996 ◽  
Vol 1996 ◽  
pp. 180-180
Author(s):  
F.R.C. Backwell ◽  
B.J. Bequette ◽  
L.A. Crompton ◽  
C.K. Reynolds ◽  
D.E. Beever ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Mammary Gland ◽  
Stable Isotope ◽  
Milk Production ◽  
Present Experiment ◽  
Milk Protein ◽  
Jugular Vein ◽  
Dairy Goats ◽  
Lactating Goats

Studies involving infusion of stable isotope labelled peptides have shown that the mammary gland has the ability to utilise peptide-derived AA for milk protein synthesis (Backwell et al., 1994a) and that peptides may be involved in the supply of phenylalanine to the mammary gland in vivo (Backwell et al., 1994b). The aim of the present experiment was to compare milk production responses to systemic (jugular vein) provision of histidine as free AA or as a peptide (glycyl-histidine) in lactating dairy goats with an induced histidine deficiency.

Effect of intravenous histidine or histidine peptide infusion on milk protein yield in lactating goats with an induced histidine deficiency

1996 ◽  
Vol 1996 ◽  
pp. 180-180
Author(s):  
F.R.C. Backwell ◽  
B.J. Bequette ◽  
L.A. Crompton ◽  
C.K. Reynolds ◽  
D.E. Beever ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Mammary Gland ◽  
Stable Isotope ◽  
Milk Production ◽  
Present Experiment ◽  
Milk Protein ◽  
Jugular Vein ◽  
Dairy Goats ◽  
Lactating Goats

Studies involving infusion of stable isotope labelled peptides have shown that the mammary gland has the ability to utilise peptide-derived AA for milk protein synthesis (Backwell et al., 1994a) and that peptides may be involved in the supply of phenylalanine to the mammary gland in vivo (Backwell et al., 1994b). The aim of the present experiment was to compare milk production responses to systemic (jugular vein) provision of histidine as free AA or as a peptide (glycyl-histidine) in lactating dairy goats with an induced histidine deficiency.

scholarly journals Identification of the Potential Role of the Rumen Microbiome in Milk Protein and Fat Synthesis in Dairy Cows Using Metagenomic Sequencing

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1247
Author(s):  
Xin Wu ◽  
Shuai Huang ◽  
Jinfeng Huang ◽  
Peng Peng ◽  
Yanan Liu ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Amino Acid ◽  
Milk Fat ◽  
Milk Protein ◽  
Volatile Fatty Acids ◽  
Rumen Fluid ◽  
Abundant Species ◽  
Metagenomic Sequencing ◽  
Amino Acid Synthesis ◽  
Prevotella Species

The rumen contains abundant microorganisms that aid in the digestion of lignocellulosic feed and are associated with host phenotype traits. Cows with extremely high milk protein and fat percentages (HPF; n = 3) and low milk protein and fat percentages (LPF; n = 3) were selected from 4000 lactating Holstein cows under the same nutritional and management conditions. We found that the total concentration of volatile fatty acids, acetate, butyrate, and propionate in the rumen fluid was significantly higher in the HPF group than in the LPF group. Moreover, we identified 38 most abundant species displaying differential richness between the two groups, in which Prevotella accounted for 68.8% of the species, with the highest abundance in the HPF group. Functional annotation based on the Kyoto Encyclopedia of Gene and Genome (KEGG), evolutionary genealogy of genes: Non-supervised Orthologous Groups (eggNOG), and Carbohydrate-Active enzymes (CAZy) databases showed that the significantly more abundant species in the HPF group are enriched in carbohydrate, amino acid, pyruvate, insulin, and lipid metabolism and transportation. Furthermore, Spearman’s rank correlation analysis revealed that specific microbial taxa (mainly the Prevotella species and Neocallimastix californiae) are positively correlated with total volatile fatty acids (VFA). Collectively, we found that the HPF group was enriched with several Prevotella species related to the total VFA, acetate, and amino acid synthesis. Thereby, these fulfilled the host’s needs for energy, fat, and rumen microbial protein, which can be used for increased biosynthesis of milk fat and milk protein. Our findings provide novel information for elucidation of the regulatory mechanism of the rumen in the formation of milk composition.

scholarly journals Genome-wide analysis of long non-coding RNAs (lncRNAs) in two contrasting soybean genotypes subjected to phosphate starvation

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Jinyu Zhang ◽  
Huanqing Xu ◽  
Yuming Yang ◽  
Xiangqian Zhang ◽  
Zhongwen Huang ◽  
...  
Keyword(s):  
Growth And Yield ◽  
Biological Processes ◽  
Rna Seq ◽  
Plant Growth And Development ◽  
P Deficiency ◽  
Genome Wide ◽  
Low Phosphorus ◽  
Soybean Genotypes ◽  
Non Coding Rnas ◽  
Sensitive Genotype

Abstract Background Phosphorus (P) is essential for plant growth and development, and low-phosphorus (LP) stress is a major factor limiting the growth and yield of soybean. Long noncoding RNAs (lncRNAs) have recently been reported to be key regulators in the responses of plants to stress conditions, but the mechanism through which LP stress mediates the biogenesis of lncRNAs in soybean remains unclear. Results In this study, to explore the response mechanisms of lncRNAs to LP stress, we used the roots of two representative soybean genotypes that present opposite responses to P deficiency, namely, a P-sensitive genotype (Bogao) and a P-tolerant genotype (NN94156), for the construction of RNA sequencing (RNA-seq) libraries. In total, 4,166 novel lncRNAs, including 525 differentially expressed (DE) lncRNAs, were identified from the two genotypes at different P levels. GO and KEGG analyses indicated that numerous DE lncRNAs might be involved in diverse biological processes related to phosphate, such as lipid metabolic processes, catalytic activity, cell membrane formation, signal transduction, and nitrogen fixation. Moreover, lncRNA-mRNA-miRNA and lncRNA-mRNA networks were constructed, and the results identified several promising lncRNAs that might be highly valuable for further analysis of the mechanism underlying the response of soybean to LP stress. Conclusions These results revealed that LP stress can significantly alter the genome-wide profiles of lncRNAs, particularly those of the P-sensitive genotype Bogao. Our findings increase the understanding of and provide new insights into the function of lncRNAs in the responses of soybean to P stress.

scholarly journals Influence of a nonforage diet on plasma leptin in dairy goats throughout lactation

2002 ◽  
Vol 2002 ◽  
pp. 97-97
Author(s):  
F. Rosi ◽  
L. Rapetti
Keyword(s):  
Energy Homeostasis ◽  
Peptide Hormone ◽  
Dairy Goats ◽  
Lactating Goats ◽  
Energy Stores ◽  
The Status ◽  
Plasma Leptin ◽  
Body Energy ◽  
The Brain ◽  
By Products

Leptin is a 16kDa peptide hormone mainly secreted by fat cells to regulate of food intake and energy homeostasis, and to signal the status of body energy stores to the brain (Houseknecht et al., 1998). In ruminant, reducing feedstuffs particle size increases DM intake, particularly if feedstuffs quality is poor, due to a shorter retention time of the particles in the rumen. By-products are included in the ration to supply energy and protein, but they have often a high content of fibre. The by-product fibre has different properties than forage NDF, being characterised by particles of small dimensions and a high density. The aim of this study was to compare the plasma level of leptin in lactating goats fed a traditional silage-based diet or a totally free forage diet, throughout lactation and during the pre and post-feeding state.

scholarly journals Partial replacement of corn by forage cactus in the diets of lactating goats

2016 ◽  
Vol 37 (2) ◽  
pp. 969 ◽  
Author(s):  
Julianne Santiago Silva Goveia ◽  
Veronaldo Souza de Oliveira ◽  
Gladston Rafael De Arruda Santos ◽  
Karla Dias Antunes Melo ◽  
Aline Guimarães de Oliveira ◽  
...  
Keyword(s):  
Milk Production ◽  
Latin Square ◽  
Gliricidia Sepium ◽  
Neutral Detergent Fiber ◽  
Ingestive Behavior ◽  
Partial Replacement ◽  
Dairy Goats ◽  
Lactating Goats ◽  
Body Weights ◽  
Daily Milk Production

The objective of this trial was to evaluate the effect of the partial replacement of corn by forage cactus (Nopalea cochenillifera Salm Dyck) in the diets of lactating goats on the nutrient intake, milk production and composition and ingestive behavior. Five crossbreed Saanen x Pardo Alpina goats with body weights of 47 ± 3.3 kg were used in the study. The design was 5x5 Latin square design, in which the treatments were as follows: 20, 25, 30, 35 and 40% of girl cactus included in the diet as a partial replacement of corn, with 0, 18, 36, 54 and 72% of the added the cactus comprising of gliricidia (Gliricidia sepium (Jacq) Walp) as roughage in all treatments. Treatment did not affect (P > 0.05) the dry matter intake, crude protein, neutral detergent fiber, acid detergent fiber and total digestible nutrients with the increasing levels of cactus in the diet, presenting means of 1.64, 0.26, 0.82, 0.54 and 1.17 kg day-1, respectively. In the same way, no influence was observed on the daily milk production and levels of fat, protein, lactose and total solids of milk, which averaged 1.18 kg day-1; 3.74, 3.34, 5.06 and 13.56%, respectively. The inclusion of cactus also had no influence (P > 0.05) on the ingestion behavior. The treatment with 35% cactus showed a lower impairment of food intake (31%). The partial replacement of the corn by the girl cactus in the diets of dairy goats can be accomplished because it does not alter the intake, milk yield and composition and feeding behavior. The replacement of up to 54% corn by the cactus is recommended to reduce producer costs for food.

Milk protein precursors in lactating goats

1992 ◽  
Vol 1992 ◽  
pp. 2-2 ◽  
Author(s):  
B J. Bequette ◽  
C. Backwell ◽  
G.E. Lobley ◽  
J.C. MacRae
Keyword(s):  
Mammary Gland ◽  
Dietary Fat ◽  
Nutritional Value ◽  
Milk Protein ◽  
Integrated Approach ◽  
Fat Intake ◽  
Lactating Goats ◽  
Lactating Mammary Gland ◽  
Milk Component ◽  
Kinetics Of

With the failure of current nutritional schemes for dairy ruminants to predict yields of milk and milk components, and perceptions of milk's nutritional value following recommendations to reduce dietary fat intake, an integrated approach to feeding and metabolism needs to be developed. Such a system must therefore be ‘metabolite’ based.An ability to predict changes in milk constituent output in response to alterations in nutrition requires, in the first instance, the identification of specific precursors for milk component synthesis in the lactating mammary gland. Arteriovenous differences across the mammary gland indicate that blood free amino acids (AA) are either taken-up by the gland in excess, equal to, or in insufficient amounts compared to their output in milk (1). Isotope labelling experiments have indicated that, in addition to AA free in blood, the mammary gland utilises a substantial amount of AA derived from constitutive mammary gland protein breakdown (2). The present experiment was designed to investigate the AA precursors and kinetics of milk protein synthesis and to confirm and extend the latter observations.

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