THE EFFECT OF LACTATION ON OUABAIN-SENSITIVE RESPIRATION OF THE DUODENAL MUCOSA OF COWS

1984 ◽  
Vol 64 (4) ◽  
pp. 817-824 ◽  
Author(s):  
B. W. McBRIDE ◽  
L. P. MILLIGAN

Total O2 consumption, ouabain-sensitive and ouabain-insensitive respiration rates were measured for the duodenal mucosa of non-lactating and lactating cows. Support of Na+, K+-ATPase activity, as measured by ouabain-sensitive respiration, accounted for 55% of total mucosal respiration of the cows at peak lactation. In mid-lactation and during the non-lactating period the proportion of O2 uptake inhibited by ouabain declined to 34–35%; the amount of ouabain-sensitive O2 uptake declined from 3.6–4.0 to 2.5–2.8 μL O2/mg tissue per hour. The magnitude of ouabain-insensitive respiration was highest during late lactation and the non-lactating period. It was concluded that Na+, K+-ATPase accounted for a major proportion of the duodenal mucosa maintenance energy expenditure. The magnitude of this expenditure is not constant throughout lactation. Key words: Na+, K+-ATPase, duodenal mucosa, O2 consumption, cows

1992 ◽  
Vol 72 (2) ◽  
pp. 413-416 ◽  
Author(s):  
B. W. McBride ◽  
J. H. Burton ◽  
G. K. MacLeod ◽  
R. J. Early

The maintenance energy expenditure associated with Na+, K+-transport and protein synthesis within skeletal muscle was determined for rbST-treated and untreated cows. Somatotropin had no effect on elevating the respiration of skeletal muscle or the partitioning of maintenance energy expenditures within skeletal muscle. Key words: O2 consumption, somatotropin, Na+, K+-ATPase, protein synthesis


1983 ◽  
Vol 63 (1) ◽  
pp. 155-162 ◽  
Author(s):  
L. KUNG Jr. ◽  
B. W. JESSE ◽  
J. W. THOMAS ◽  
J. T. HUBER ◽  
R. S. EMERY

Whole barley was treated with sodium hydroxide (NaOH) in laboratory trials. Dry matter disappearance from nylon bags in the rumen of whole barley treated with 2.5, 3.5, or 4.9% NaOH for 30 h was 59.6, 72.4, and 93.0%, respectively, compared with 82.2% for untreated ground barley. In a subsequent lactation trial, 24 Holstein cows (eight per treatment) were fed high moisture ground ear corn, high moisture rolled barley or high moisture whole barley treated with 3.5% NaOH. Milk persistencies tended to be greater for cows fed high moisture rolled barley, next for ground ear corn and least for NaOH-treated barley. Milk composition was similar for all treatments. Dry matter intake was greatest for cows fed ground ear corn and lower for those fed the barley diets. Alpha-linked glucose and pH of feces were similar for cows fed ground ear corn and high moisture rolled barley diets, but fecal pH was lower and alpha-linked glucose concentrations three times greater for NaOH-treated barley. Digestibility percents of dry matter, acid detergent fiber and nitrogen were 61.4, 25.3, 64.7 for ground ear corn; 64.4, 38.0, 67.1 for high moisture rolled barley; and 56.8, 43.2, 54.8 for NaOH-treated barley, respectively. Rumen grain turnover estimated by excretion of ytterbium in feces was greatest for NaOH-treated barley (9.09%/h), intermediate for ground ear corn (6.10%/h) and lowest for high moisture rolled barley (4.93%/h). Key words: Dairy, sodium hydroxide, high moisture grains


1978 ◽  
Vol 35 (6) ◽  
pp. 816-821 ◽  
Author(s):  
J. R. Brett ◽  
J. M. Blackburn

The metabolic rate of spiny dogfish, Squalus acanthias, was determined in both a tunnel respirometer and a large, covered, circular tank (mass respirometer). Swimming performance was very poor in the respirometer, so that a power–performance curve could not be established. Instead, resting metabolic rates were determined, with higher rates induced by causing heavy thrashing (active metabolism). Routine metabolic rates were measured for the spontaneous activity characterizing behavior in the circular tank. For fish of 2 kg mean weight, the metabolic rates at 10 °C were 32.4 ± 2.6 SE (resting), 49.2 ± 5.0 SE (routine), and 88.4 ± 4.6 SE (active) mg O2∙kg−1∙h−1. Assuming that the routine rate represents a general energy expenditure in nature, this is equivalent to metabolizing about 3.8 kcal∙kg−1∙d−1 (15.9 × 103 J∙kg−1∙d−1). Key words: dogfish, metabolic rates, energetics, respiration


2007 ◽  
Vol 87 (4) ◽  
pp. 455-458 ◽  
Author(s):  
Martin T Moroni ◽  
Paul Q Carter ◽  
Dean W Strickland ◽  
Franz Makeschin ◽  
Don-Roger Parkinson ◽  
...  

Clearcutting Newfoundland boreal forests significantly reduced organic layer fungal and total microbial biomass in clearcut areas with and without slash cover, compared with forested plots. However, aerobically incubated respiration rates were highest in organic layers from clearcut areas under slash, intermediate under forests, and lowest from clearcut areas without slash. Key words: Carbon, ergosterol, fumigation–extraction, fungal biomass, harvest slash, nitrogen


2018 ◽  
Vol 5 (1) ◽  
pp. 70-76
Author(s):  
Debbye Chávez ◽  
Julio Villacres Matías

El presente estudio guarda estrecha relación con la alimentación de caprinos, las ganancias de peso y su producción; sabiendo que, para que un animal logre buenos rendimientos productivos se hace necesaria una alimentación que cubra necesidades energéticas de mantenimiento, luego de crecimiento y ganancia de peso o de producción; se determinó el recorrido en unidades de desplazamiento; luego, por medio de fórmulas de medición energética trasformar esto a energía metabolizable que es una unidad fácilmente relacionable con las necesidades energéticas de mantenimiento y de producción, siendo 60 cabras de diferentes razas las que se consideraron en este estudio, donde se registró su peso, y edad antes de que formen parte del ensayo. Con la ayuda de podómetros calibrados para usarlos en cabras, se determinó el recorrido habitual. Los podómetros fueron colocados en uno de sus miembros posteriores a la altura de la rodilla, y retirados 24h después, registrando su desplazamiento y actividades en busca del alimento. Utilizando Excel se procedió a la tabulación y organización de los datos, que fueron sometidos a estadística descriptiva y análisis de la información, como resultado se evidenció 5Km de recorridos por animal, con edades entre 2,5 años de promedios, de igual forma las razas de cabras más frecuentes fueron, en primer lugar la Criolla y en segundo la Nubia; ambas razas de animales no se diferenciaron en el recorrido y peso, lo que permitió utilizar una forma universal de estimación del gasto energético (0,49 kcal/kg /km) pudiéndose determinar que fueron 87,69Kcal involucradas en 24h de actividad. ABSTRACT This study is closely related to feeding goats, weight gain and production; knowing that, for an animal to achieve good production yields a feed that covers maintenance energy requirements is necessary , after growth and weight gain or production a route was determined in units of displacement; then by using formulas of energetic measurement transform these to metabolizable energy which is a easily relatable unit with the energetic requirements of maintenance and production, 60 goats from different races were considered in this study, in which their weight and ages were recorded before forming part of the test. With the help of pedometers calibrated for use in goats, the usual route is determined. Pedometers were placed in one of his post-kneemembers, and retired after 24h, recording their movement and activities in search of food. Using Excel proceeded to the tabulation and organization of data, which were subjected to descriptive statistics and analysis of information, as a result of tours 5Km animal showed, aged 2.5 years average, similarly races more frequent goats were first Creole and secondly the Nubia; both breeds of animals did not differ in the way and weight, enabling use a universal way to estimate energy expenditure (0.49 kcal / kg / km) being able to determine which were involved in 24h 87,69Kcal activity.


2000 ◽  
Vol 278 (3) ◽  
pp. R669-R676 ◽  
Author(s):  
Michael Scantlebury ◽  
Waring Hynds ◽  
Derek Booles ◽  
John R. Speakman

Isotope-based techniques for the measurement of water turnover, energy expenditure, and milk intake often assume that there is no recycling of isotopes once they have left the labeled animal. In experiments involving lactating females or their suckling offspring, there are several possible routes of isotope recycling. These include the consumption of labeled milk by offspring, the ingestion of labeled excreta, and the rebreathing of exhaled labeled CO2 or water vapor by both mother and offspring. Isotope recycling might be especially important during lactation because the offspring are in close contact with each other and their mother for prolonged periods. We show here in 24- to 30-day-old domestic dog Canis familiarispuppies that there was no detectable transfer of 18O or2H from labeled to unlabeled pups in two litters (16 pups, 8 labeled, 8 unlabeled) that were weaned early and independent of their mother. However, there was a significant transfer of both isotopes from labeled to unlabeled pups and from labeled pups to their mothers in nine equivalent nursing litters of the same age (27 labeled, 26 unlabeled pups). The increases in enrichment of isotopes in unlabeled offspring were greater than the increases in enrichment of the mothers. This indicates that maternal ingestion of offspring excreta and subsequent transfer of isotope in milk is not the sole pathway of recycling. Additional routes must also be important, such as exchange of isotope between pups on saliva-coated nipples and perhaps direct ingestion of excreta by unweaned young. Recycling is unlikely to be an important factor when determining maternal metabolic rate during peak lactation in domestic dogs. However, experiments that are designed to assess the energy demands of pups and isotope-based estimates of water turnover in offspring may need to take into account any effects of isotope recycling. In a theoretical example, removing the effects of recycling increased the measured energy expenditure in pups by up to 7% and increased the calculated elimination rates of both isotopes by up to 11.1% in 18oxygen and 10.9% in2hydrogen.


2019 ◽  
Vol 41 (6) ◽  
pp. 497 ◽  
Author(s):  
Lester Pahl

The extent to which goats and cattle eat equivalent amounts of forage as sheep has been based on their maintenance energy requirements (MERs) relative to a 50kg wether or dry ewe, known as a dry sheep equivalent (DSE). As such, a 50kg goat was considered 1 DSE and a 450kg steer as 7–8 DSE. In comparison, the DSE of macropods has been based on their basal metabolic rate (BMR) or energy expenditure of grazing (EEg) relative to those of sheep, with a 50kg macropod thought to be 0.7 and 0.45 DSE respectively. Based on published energy requirements of goats, macropods and cattle relative to sheep, their DSE values are estimated to be 1.2, 1.0 and 7.6 respectively. However, relative energy requirements may not be the same as relative dry matter intakes (DMIs), due to differences in forage quality, the structure of digestive tracts and selective foraging capabilities. Allometric equations that predict DMI were developed from published liveweights and intakes of sheep, goats, macropods and cattle. Given DMIs when fed high-quality forage, a 50kg goat was 1 DSE, a 50kg macropod was 0.7 DSE and a 450kg steer was 7.6 DSE. Their DMIs were depressed by 35–50% when fed low-quality forage, but a goat remained as 1 DSE, macropods increased to 1.0 DSE and cattle increased to 8.3 DSE. The capacity of macropods to maintain relatively higher DMIs of low-quality forage than sheep is probably due of their faster digesta passage rates and more expandable stomachs. These DMIs of animals provided ad-libitum quantities of similar forages in small pens are likely to differ from their DMIs when selectively grazing heterogeneous rangeland pastures. Under these conditions, sheep select higher-quality diets than cattle, and kangaroos select higher-quality diets than sheep, which increase the relative DMIs of the smaller herbivores. For this reason, a 50kg macropod is likely to be 1 DSE and consume twice as much forage than previously assumed.


1985 ◽  
Vol 65 (4) ◽  
pp. 667-675 ◽  
Author(s):  
E. B. ROSLYCKY

Adaptations of eight strains of rhizobia from seven cross-inoculation groups and of two agrobacteria from two species to paraquat, in concentrations up to 20 000 μg∙mL−1, affected 11 of the 40 properties studied, including carbohydrate, nitrogen, sulfur, and other metabolism. The number of characteristics altered varied among the bacteria without species or group affiliation. Of the total of 18 changes, 13 occurred in Rhizobium meliloti 22 and R. trifolii 7 and 42, while R. leguminosarum 56, R. lupini 112, R. japonicum 80, cowpea strain 131, and Agrobacterium tumefaciens A6-K1 had only one. Rhizobium phaseoli 95 and A. radiobacter R-590 remained unaffected. Generally, the adapted organisms produced lower nephelometric growth and manometric respiration rates at 0 and 200 μg of paraquat∙mL−1, relative to the herbicide-free parent controls. Tolerance of R. trifolii 7 to NaCl increased from 1% to 5% (wt/vol). The findings suggest that paraquat may have affected cell permeability, adaptive and/or constitutive enzymes in these bacteria. Key words: Rhizobia, agrobacteria, adaptations, physiology, paraquat and herbicides


2017 ◽  
Vol 57 (7) ◽  
pp. 1219 ◽  
Author(s):  
Ashleigh M. Wildridge ◽  
Sergio C. Garcia ◽  
Peter C. Thomson ◽  
Ellen C. Jongman ◽  
Cameron E.F. Clark ◽  
...  

During hot weather cows typically reduce feed intake and actively seek shade and water to reduce the metabolic stress on their bodies. This can have a negative impact on the occurrence of voluntary milking visits to an automatic milking system (AMS) operating with voluntary traffic, thus reducing milking frequency. Shade is known to be effective in alleviating heat stress in dairy cattle; however, the impact of providing shade at the milking facility of a pasture-based AMS on time taken to voluntarily enter a milking unit is unknown. A herd of ~300 lactating cows milked in a pasture-based AMS were divided into two groups during the summer of 2016. Each group spent 4 weeks in a SHADE (predominately shaded pre-milking yard) and a NO-SHADE (predominantly non-shaded pre-milking yard) treatment, with two periods in a crossover design. Cow respiration rates, time spent in pre- and post-milking areas, concentrate consumption and milk yield were recorded. On average, cows in the SHADE treatment were found to take longer to enter the milking unit than did cows in the NO-SHADE treatment (SHADE = 11.40 min, NO-SHADE = 8.70 min, P < 0.001). SHADE was also associated with lower average respiration rates (SHADE = 68 breaths per minute (bpm), NO-SHADE = 73 bpm, P < 0.001), increased concentrate consumption (SHADE = 6.50 kg/cow.day, NO-SHADE = 6.39 kg/cow.day, P = 0.03) and increased milk yield (SHADE = 11.44 kg/cow.milking, NO-SHADE = 10.95 kg/cow.milking, P < 0.001). Overall, SHADE made available to the cows pre-milking appeared to improve cow performance and comfort (as indicated by reduced respiration rates).


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