scholarly journals A preliminary study of the effect of pregnancy and of lactation on the voluntary intake of food by cows

1966 ◽  
Vol 20 (1) ◽  
pp. 25-39 ◽  
Author(s):  
R. C. Campling
Keyword(s):  
Twin Pair ◽  
Monozygotic Twin ◽  
The Other ◽  
Early Lactation ◽  
Pregnant Animal ◽  
Lactating Cows ◽  
The Mean ◽  
Preliminary Study ◽  
Voluntary Intake

1. Monozygotic twin cattle were used in a preliminary study of the effect of pregnancy and of lactation on the voluntary intake of food and water, and on eating and ruminating behaviour. Also, results are reported of an experiment with five pairs of monozygotic twin heifers to examine the variation within pairs of twins in voluntary intake of food and water and eating and ruminating behaviour.2. Voluntary food and water intakes were measured during the last few weeks of pregnancy and during early lactation. Within each twin pair one twin was pregnant or lactating and the other non-lactating and not pregnant, and the food and water intakes of a pair of twins were measured simultaneously.3. On average the variation in voluntary intake of hay within pairs of non-pregnant, monozygotic twin heifers was 0.2 kg or 3 % of the mean daily hay intake.4. The effect of pregnancy was observed in six pairs of twins and in five of the pairs the pregnant animal ate iess hay than its non-pregnant twinmate; in four of these five pairs the effect was small (13 % ). Changes in eating and ruminating behaviour associated with pregnancy were small; the pregnant animals ate concentrates and hay more slowly and ruminated longer than the non-pregnant animals.5. Lactation was associated with a mean increase of 29 % in hay intake in eight out of the nine pairs studied. In four pairs of twins given a diet of concentrates alone the lactating animal ate on average 8 % more than the non-lactating animal. The lactating cows tended to eat concentrates and hay more quickly than the non-lactating cows; because of differences in the ratio of hay to concentrates it was not possible to interpret the changes in rumination that occurred with lactation.

Effect of time of joining and rate of stocking on the production of Corriedale ewes in southern Victoria. 3. Wool growth and the composition and availability of pasture

1975 ◽  
Vol 15 (73) ◽  
pp. 159 ◽  
Author(s):  
PA Kenney ◽  
IF Davis
Keyword(s):  
Fibre Diameter ◽  
Late Pregnancy ◽  
The Other ◽  
Early Lactation ◽  
Stocking Rate ◽  
Wool Production ◽  
Wool Growth ◽  
The Mean ◽  
Brome Grass ◽  
Stocking Rates

A study was made during a three year period (1 968-1 970) of wool production by a flock of 540 ewes grazing annual pasture at Werribee, Victoria. The ewes were stocked at three rates (5, 7 1/2 and 10 ewes ha-1) and lambed between July 6 and August 20 or between September 10 and October 29 each year. Fibre diameter and length of wool samples were measured in 1968, 1969 and 1970 ; in 1970 growth of greasy wool was calculated from staples of dye-banded wool. Wool growth was reduced in all ewes during late pregnancy and early lactation but was not affected during late lactation in ewes lambing in September. The proportion of tender fleeces from all ewes was greater in 1970 and the weight of fleeces from only those ewes bearing single lambs was less in all years for ewes lambing in July than for ewes lambing in September. More ewes were barren and fewer ewes had twins in July and consequently the mean fleece weights of all ewes from both groups were similar. Fleeces from ewes stocked at 10 ha-1 were lighter, shorter and finer than fleeces from ewes stocked at 5 and 7 1/2 ha-1, but the proportion of tender fleeces did not differ between the groups. Wool production of ewes stocked at 5 and 7 1/2 ha-1 increased from 1968 to 1970, whereas that of ewes at 10 ha-1 did not. This was associated with differences in pasture availability and composition. At 10 ewes ha-1 less pasture was present in winter and spring in 1970 than in 1968, whereas at the other stocking rates it was greater. In 1970 the density of weeds in autumn was greater and in spring more silver grass (Vulpia spp.) and less brome grass (Bromus spp.) was available at the high stocking rate.

Eating and ruminating behaviour in cattle given forages differing in fibre content

1989 ◽  
Vol 48 (3) ◽  
pp. 503-511 ◽  
Author(s):  
M. N. McLeod ◽  
B. R. Smith
Keyword(s):  
Dry Matter ◽  
The Other ◽  
Fibre Content ◽  
Eating Rate ◽  
High Fibre ◽  
Acid Detergent Fibre ◽  
The Mean ◽  
Voluntary Intake ◽  
Mean Time ◽  
Forage Diets

ABSTRACTA study was made of the effect of fibre level in forages on eating and rumination behaviour. Eight forage diets were prepared from the leaf and stem fractions of two grasses and two legumes and were given at hourly intervals to four steers under steady-state conditions. Eating and rumination behaviour were measured automatically by recording changes in intra-oesophageal pressure.Mean voluntary intake of leaf was higher than that of the stem fractions (9·9 v. 5·6 kg/day; P < 0·001). This was associated with a shorter mean retention time in the rumen of the leaf than that of the stem fractions (21·4 v. 30·6 h; P < 0·001) and a lower concentration (g/100 g dry matter (DM)) of fibre (52-0 neutral-detergent fibre (NDF) and 30·5 acid-detergent fibre (ADF) v. 68·2 NDF and 45·3 ADF). Similar values (P > 0·05) between diets were found for both the water and DM contents of the rumen (60·1 kg, 7·8 kg). Voluntary intake was not related to either.No difference was found between forage diets in the mean time (132 min) and number (18·7) of periods spent eating each day (P > 0·05). Legume leaf fractions were eaten at a faster rate (g/min) than either the grass leaf or the stem fractions. Voluntary intake was related to the rate at which food was eaten (r = 0·89; P < 0·01) but no relationship was found with the time taken to eat food (r = –0·14; P>0·05). Eating rate was related to the level of both NDF (r = –0·91; P < 0·01) and ADF (r = –0·96; P < 0·001).Differences between diets were found in rumination times (mean 425 min; P < 001), the number of boluses regurgitated during each period (27·6; P < 0·05) and during each day (485; P < 0·001), and in the weight of boluses (455 g; P < 0·05). No differences (P > 0·05) were found between diets in the mean number of rumination periods each day (17·6), the mean time spent ruminating during each period (24·3 min), the mean rate at which boluses were regurgitated (53·2 s per bolus), the interval between boluses (5·1 s), and the DM in a bolus (27·5 g). Rumination time and the number of boluses regurgitated either per period or per day were not related to the fibre content of the diet (P > 0·05).The regurgitated boluses from leaf fractions were chewed less than the stem fractions (43·7 v. 54·7 chews per bolus). The regurgitated boluses of lucerne leaf were chewed at a faster rate (1·13 chews per s; P > 0·05) than regurgitated digesta of the other diets which were chewed at similar rates (0·97 chews per s; P > 0·05). The total number of rumination chews made each day by animals given lucerne leaf (12 300) was much lower (P < 0·001) than that by animals given the other fractions (25 300). The number of chews made on each bolus was related to fibre levels in the diets (NDF, r = 0·78, P < 0·05; ADF, r = 0·91, P < 0·01).It is concluded that the voluntary intake of high-fibre diets is not always restricted by rumen fill or rumination. The ease with which forage is eaten should be investigated as a factor influencing intake of fibrous forages.

Depressing Effect of Rumen Distension on Silage Intake of the Lactating Dairy Cow

1988 ◽  
Vol 1988 ◽  
pp. 82-82
Author(s):  
J.N. Mbanya ◽  
M.H. Anil ◽  
J.M. Forbes
Keyword(s):  
Latin Square ◽  
Depressing Effect ◽  
Lactating Cows ◽  
Lactating Dairy Cows ◽  
Preliminary Study ◽  
Voluntary Intake ◽  
Daily Milk Yield ◽  
Different Levels ◽  
Daily Milk ◽  
Friesian Cows

The numerous factors involved in the control of food intake by ruminants have been reviewed in detail (Baile and Forbes, 1974.). Distension of the rumen is thought to limit the voluntary intake of hay by dry cows (Campling and Balch, 1961) and by lactating cows (Mbanya, Anil and Forbes, 1987). In more recent reports, it is thought that some of these factors which are negative feedback signals combine additively in their effects to induce satiety (Forbes, 1986). Prior to investigating the additive effects of rumen distension to those of other feedback signals on intake of silage by lactating dairy cows, we carried out a preliminary study now reported to establish a response curve to different levels of distension which will enable an appropriate degree of distension to be imposed in future experiments involving combinations of treatments.Animals and Housing - Five rumen fistulated, non-pregnant Friesian cows in early lactation (mean daily milk yield, 25.2 kg) were used in a 5 x 5 Latin square design with a row omitted.

Vascular Etiology of Disruptive Structural Defects in Monozygotic Twins

PEDIATRICS ◽  
1981 ◽  
Vol 67 (2) ◽  
pp. 288-291
Author(s):  
H. Eugene Hoyme ◽  
Marilyn C. Higginbottom ◽  
Kenneth L. Jones
Keyword(s):  
Spinal Cord ◽  
Twin Pair ◽  
Monozygotic Twins ◽  
Horseshoe Kidney ◽  
Monozygotic Twin ◽  
Recurrence Risk ◽  
The Other ◽  
Structural Defects ◽  
Monozygotic Twin Pair ◽  
Vascular Accidents

Two infants with structural defects previously undescribed in the survivor of a monozygotic twin pair are reported. One infant had hydranencephaly and a spinal cord transection, with an associated dead monozygotic co-twin of 24 weeks gestation; the other child had complete atresia of the colon and a horseshoe kidney, with a deceased co-twin of approximately six weeks gestation. These defects are presumed to be the result of in utero disruption of previously normally formed structures. They occur secondary to vascular exchange from a dead to a living monozygotic twin through placental vascular anastomoses. As illustrated by the two children described, the nature of the vascular defects seen in the survivor of a monozygotic twin pair depends on the time during gestation at which the co-twin dies. Recognition of the disruptive vascular etiology of the structural defects outlined in this report will allow for appropriate counseling with respect to the negligible recurrence risk for similar vascular accidents.

The effect of concentrates on the rate of disappearance of digesta from the alimentary tract of cows given hay

1966 ◽  
Vol 33 (1) ◽  
pp. 13-23 ◽  
Author(s):  
R. C. Campling
Keyword(s):  
Organic Matter ◽  
Alimentary Tract ◽  
Crude Fibre ◽  
Lactating Cows ◽  
The Mean ◽  
Voluntary Intake ◽  
Mean Time

SummaryTwo experiments were conducted with non-lactating cows to examine the effect of adding concentrates to a diet of hay on the rate of disappearance of digesta from the alimentary tract. The addition of large amounts of concentrates to the diet of cows offered hay ad lib. decreased the voluntary intake of hay, increased slightly the digestibility of the organic matter and decreased markedly the digestibility of the crude fibre of the diet. Also, the addition of concentrates increased the mean time of retention of stained hay residues in the alimentary tract and increased the time/kg hay the cows spent ruminating. At the end of a meal the amount of digesta in the reticulo-rumen of the cows offered hay ad lib. with restricted amounts of concentrates was about the same as that found when offered hay ad lib. as the only food. The results are discussed in relation to the regulation of the voluntary intake of hay by the cow.

Sources of variation in the fertility of a herd of zebu, British, and zebu × British cattle in Northern Australia

1973 ◽  
Vol 81 (2) ◽  
pp. 253-262 ◽  
Author(s):  
R. M. Seebeck
Keyword(s):  
Variance Components ◽  
Opposite Effect ◽  
The Other ◽  
Low Fertility ◽  
High Fertility ◽  
Lactating Cows ◽  
Sources Of Variation ◽  
The Mean ◽  
The Difference ◽  
Made In

SummaryResults of matings made in the Belmont breeding programme from 1954 to 1968 have been analysed. The analysis has been made within three groups. (1) The foundation cows in the years 1954–9; (2) the F1 generation which were mated within line in the years 1957–62; (3) the F2 and F3 generations which were mated within Africander cross (AX), Brahman cross (BX) and Shorthorn-Hereford (SH) lines in the years 1960–8. Fertility was based on the number of calves born, whether alive or dead, to the number of cows mated.In the foundation cows, Hereford cows had a fertility 9% higher than the Shorthorns. The difference between the bull breeds was not significant although the mean for the Brahman bulls was 16% below the mean of the other three breeds. There was a large variation in the fertility of the Brahman bulls. The fertility of the Shorthorn cows was depressed (by 8%) in the lactating cows as compared with dry cows, while there was an opposite effect in the Herefords. These latter effects showed year to year variation.In the F1 generation the differences between the breeds were not significant although both the AX (76·4%) and the BX (81·2%) were more fertile than the SH (70·1%). Estimates of heterosis in the F1 generation were 42% for the AX, 43% for the BX and 12% for the SH. Lactating cows were 7% more fertile than non-lactating cows. There were significant differences between the BX bulls used but not between bulls of the other two breeds. The effect of sires within breed on fertility of daughters was significant only within the SH, and the heritabilities of fortuity were estimated from the variance components for sires within breed to be 9%, 14% and 22% for AX, BX and SH respectively.In the F2 and F3 data the breeds were significantly different in fertility with averages of 77%, 61% and 67% for AX, BX and SH respectively. Thus by comparison with the fertilities of the F1 cows no loss of heterosis for fertility occurred in the AX, a very marked loss in the BX and only a slight loss in the SH. A significant interaction between age of cow and lactational status showed that in the mature cows, wet cows had a higher fertility than dry, while the converse applied in the 3-year-old cows. The interaction of lactational status with breed consisted of the wet zebu cross cattle having a relatively low fertility while the wet British cattle had a relatively high fertility. There were significant differences between bulls within each of the three breeds. The effect of sires was significant in the BX and SH. Heritabilities estimated from between sires within breeds variance components were – 12%, 22% and 25% for the AX, BX and SH respectively.

The effect of level of feeding on the digestibility of diets for sheep and cattle

1969 ◽  
Vol 11 (1) ◽  
pp. 11-18 ◽  
Author(s):  
J. D. Leaver ◽  
R. C. Campling ◽  
W. Holmes
Keyword(s):  
Organic Matter ◽  
Live Weight ◽  
Crude Fibre ◽  
Lactating Cows ◽  
The Mean ◽  
Ad Libitum ◽  
Voluntary Intake ◽  
Organic Matter Digestibility ◽  
Linear Decline ◽  
Male Sheep

SUMMARY1. In the first experiment, the digestibility of diets containing ratios of 1:1 and 1:4 hay to concentrates was determined at five levels of feeding in castrated male sheep. With diet 1.1, increasing the daily dry matter intake from 600 to 1400 g resulted in a linear decline in organic matter digestibility from 74·4 to 68·6%. The same increase in level of feeding led to a curvilinear decline in the organic matter digestibility of diet 1.4 from 83·0 to 75·9%.2. In a similar way the crude fibre digestibility of the diets declined as food intake increased. Also the increase in level of feeding caused a decrease in the mean retention time of stained hay in the alimentary tract.3. In a second experiment the digestibility of long dried grass offered ad libitum to eight dry and eight lactating cows was measured and compared with the digestibility of similar dried grass offered at maintenance level and ad libitum to eight castrated male sheep.4. On a metabolic live-weight basis (kg W0·73), the lactating cows ate 34% more organic matter than the dry cows and the mean voluntary intake of sheep was only 54% of the intake of dry cows.5. The organic matter digestibility for the dry cows was 1·9 units higher than that of the lactating cows and at ad libitum intake the organic matter digestibility for the sheep was 5·6 and 3·7 units lower than that of the dry and lactating cows respectively. The results are discussed in relation to the validity of extrapolating results obtained with sheep to cattle, and with non·lactating to lactating animals.

Local anesthetics. Is there an advantage to mixing solutions?

1996 ◽  
Vol 86 (10) ◽  
pp. 487-491 ◽  
Author(s):  
BM Ribotsky ◽  
KD Berkowitz ◽  
JR Montague
Keyword(s):  
The Other ◽  
Randomized Experiment ◽  
Three Solutions ◽  
Double Blind ◽  
Sensory Blockade ◽  
Significant Difference ◽  
Prolonged Duration ◽  
Clinical Advantage ◽  
The Mean ◽  
Preliminary Study

The advantages to using a 50/50 mixture of lidocaine and bupivacaine with respect to onset and duration of local anesthesia instead of using the solutions independently were evaluated. In a double-blind randomized experiment, 12 subjects, each volunteering both feet, were studied. One foot was injected with 1 ml of one of the following three solutions: 1% plain lidocaine, 0.25% plain bupivacaine (Marcaine), or a 50/50 mixture of 1% lidocaine and 0.25% bupivacaine; and in the other foot, a 1-ml injection of normal saline as a blinded control. A 5.07 (10 g) Semmes-Weinstein monofilament wire was used for testing for sensory blockade, and the onset and duration of anesthesia was recorded for each subject. It was determined that there was no significant difference in the mean onset times for the three solutions, and no significant difference between the durations of anesthesia of plain lidocaine and the 50/50 mixture. Additionally, it was determined that bupivacaine had a prolonged duration of anesthesia compared with the other two solutions. The results of this preliminary study suggest that there is no clinical advantage, with respect to onset and duration of local blockade, to using a 50/50 mixture of plain lidocaine and plain bupivacaine in place of their independent use.

Multi-Center Study of Thromboplastin Calibration Precision – Influence of Reagent Species, Composition, and International Sensitivity Index (ISI)

1993 ◽  
Vol 69 (01) ◽  
pp. 035-040 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina
Keyword(s):  
Oral Anticoagulants ◽  
International Normalized Ratio ◽  
The Other ◽  
World Health ◽  
Rabbit Brain ◽  
Sensitivity Index ◽  
Bovine Plasma ◽  
Significant Difference ◽  
The Mean ◽  
International Sensitivity Index

SummaryFour thromboplastin reagents were tested by 18 laboratories in Europe, North-America, and Australasia, according to a detailed protocol. One thromboplastin was the International Reference Preparation for ox brain thromboplastin combined with adsorbed bovine plasma (coded OBT/79), and the second was a certified reference material for rabbit brain thromboplastin, plain (coded CRM 149R). The other two thromboplastin reagents were another rabbit plain brain thromboplastin (RP) with a lower ISI than CRM 149R and a rabbit brain thromboplastin combined with adsorbed bovine plasma (RC). Calibration of the latter two reagents was performed according to methods recommended by the World Health Organization (W. H. O.).The purpose of this study was to answer the following questions: 1) Is the calibration of the RC reagent more precise against the bovine/combined (OBT/79) than against the rabbit/plain reagent (CRM 149R)? 2) Is the precision of calibration influenced by the magnitude of the International Sensitivity Index (ISI)?The lowest inter-laboratory variation of ISI was observed in the calibration of the rabbit/plain reagent (RP) against the other rabbit/plain reagent (CRM 149R) (CV 1.6%). The highest interlaboratory variation was obtained in the calibration of rabbit/plain (RP) against bovine/combined (OBT/79) (CV 5.1%). In the calibration of the rabbit/combined (RC) reagent, there was no difference in precision between OBT/79 (CV 4.3%) and CRM 149R (CV 4.2%). Furthermore, there was no significant difference in the precision of the ISI of RC obtained with CRM 149R (ISI = 1.343) and the rabbit/plain (RP) reagent with ISI = 1.14. In conclusion, the calibration of RC could be performed with similar precision with either OBT/79 or CRM 149R, or RP.The mean ISI values calculated with OBT/79 and CRM 149R were practically identical, indicating that there is no bias in the ISI of these reference preparations and that these reference preparations have been stable since their original calibration studies in 1979 and 1987, respectively.International Normalized Ratio (INR) equivalents were calculated for a lyophilized control plasma derived from patients treated with oral anticoagulants. There were small but significant differences in the mean INR equivalents between the bovine and rabbit thromboplastins. There were no differences in the interlaboratory variation of the INR equivalents, when the four thromboplastins were compared.

Prothrombin Time Standardization: Report of the Expert Panel on Oral Anticoagulant Control

1979 ◽  
Vol 42 (04) ◽  
pp. 1073-1114 ◽  
Keyword(s):  
Prothrombin Time ◽  
Expert Panel ◽  
The Other ◽  
Rabbit Brain ◽  
Calibration Constant ◽  
Freeze Dried ◽  
The Mean ◽  
Point Of Intersection ◽  
And Control ◽  
Standardization Report

SummaryIn collaborative experiments in 199 laboratories, nine commercial thromboplastins, four thromboplastins held by the National Institute for Biological Standards and Control (NIBS & C), London and the British Comparative Thromboplastin were tested on fresh normal and coumarin plasmas, and on three series of freeze-dried plasmas. One of these was made from coumarin plasmas and the other two were prepared from normal plasmas; in each series, one plasma was normal and the other two represented different degrees of coumarin defect.Each thromboplastin was calibrated against NIBS&C rabbit brain 70/178, from the slope of the line joining the origin to the point of intersection of the mean ratios of coumarin/normal prothrombin times when the ratios obtained with the two thromboplastins on the same fresh plasmas were plotted against each other. From previous evidence, the slopes were calculated which would have been obtained against the NIBS&C “research standard” thromboplastin 67/40, and termed the “calibration constant” of each thromboplastin. Values obtained from the freeze-dried coumarin plasmas gave generally similar results to those from fresh plasmas for all thromboplastins, whereas values from the artificial plasmas agreed with those from fresh plasmas only when similar thromboplastins were being compared.Taking into account the slopes of the calibration lines and the variation between laboratories, precision in obtaining a patient’s prothrombin time was similar for all thromboplastins.

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