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PubMed1986

Influence of creep feeding and dietary intake after weaning on malabsorption and occurrence of diarrhoea in the newly weaned pig.

The influence the pattern of creep feeding has on the ability of pigs to absorb xylose after weaning at three weeks old was investigated. All weaned pigs showed a reduction in their ability to absorb xylose one week after weaning, but this was not influenced by the pattern of creep feeding before weaning. Diarrhoea occurred in some animals after weaning, but did not occur in pigs which did not have access to creep food before weaning. This protective effect of withholding creep food was associated with a low dietary intake after weaning with this regimen. Pigs which developed diarrhoea tended to be those which consumed more meal after weaning than their contemporaries. Haemolytic enterotoxigenic Escherichia coli and rotaviruses were present in the faeces of most pigs after weaning, but, in those animals that ate too much and developed diarrhoea, excretion of the E coli continued for approximately twice as long as in animals that remained healthy.

Animals↗
PubMed1998

[Factors determining the successful weaning of patients with "difficult weaning"].

OBJECTIVE: Weaning from mechanical ventilation is often possible in the most of patients, even if sometimes it is very difficult. For example, 25-53% of COPD patients cannot be weaned. The different modalities used do not justify this. The aim of the study was the evaluation of a further weaning trial in tracheotomized patients who underwent mechanical ventilation for at least 15 days in several ICU and in whom several attempts of weaning failed. DESIGN: A retrospective study (January 1993-February 1995). SETTING: Intermediate Intensive Respiratory Care Unit of Centro Medico Di Montescano. PATIENTS: Thirty-nine patients (29 male; 26 COPD, 3 post-surgery respiratory failure, 5 restrictive diseases, 4 with cardiovascular failure and 1 neurological disease) who had been tracheotomized and undergoing mechanical ventilation from at least 15 days. An initial evaluation in which respiratory mechanics and echocardiography were performed was made and then they underwent further weaning trials based on progressive decrease of the level of pressure support and periodic disconnection from MV and on medical therapy and strong physiokinesitherapy. RESULTS: Twenty-six out of 39 patients (66%) could reach definitive weaning (COPD 65%, post-surgery respiratory failure 66%, restrictive 60%, cardiovascular failure 100%, neurological disease 0%) after 17 days of average time of ventilation (range from 4 to 90). Among the important factors in determining a difficult or impossible weaning there are: a) previous wrong ventilation settings 8/26; b) cardiovascular problems 7/26; c) alterations in respiratory mechanics 2/26; d) previous excessive sedation 2/26; e) uncorrect timing of disconnection 2/26; f) poor physiokinesitherapy 2/26; g) unknown causes 3/26. Also the ICU from which the patients has been transferred plays an important role. CONCLUSIONS: The conclusion is drawn weaning from mechanical ventilation can be reached also in a part of those patients who are thought not weanable with a further, prolonged and expensive weaning trial.

Aged↗
PubMed2004

Influence of weaning and effect of post weaning dietary zinc and copper on electrophysiological response to glucose, theophylline and 5-HT in piglet small intestinal mucosa.

This study aimed to examine how weaning and how dietary zinc and/or copper fed post weaning may affect the electrophysiological response to glucose and to chloride secretagogues in piglet small intestine in vitro. Study 1 included 54 piglets (six litters of nine piglets). One piglet from every litter was killed 1 day before weaning. The remaining 48 piglets were allocated at weaning (28 d) to four dietary zinc treatments and subsequently killed 1-2, 5-6 or 14-15 days after weaning. Study 2 included 48 piglets (six litters of eight piglets) allocated to four dietary treatments, consisting of high or low dietary zinc with or without high dietary copper. All piglets in study 2 were killed 5-7 days after weaning. The in vitro studies in Ussing chambers showed that weaning resulted in increased ileal glucose absorption as well as increased neuroendocrine-regulated (activated by 5-HT) and cAMP-dependent (activated by theophylline) chloride secretion. High zinc supplementation reduced the responses to 5-HT and theophylline. The study did not reveal any influence of copper on these parameters. It is concluded that the positive effect of zinc supplementation on diarrhoea in weaned piglets may be due to zinc reducing the intestinal mucosal susceptibility to secretagogues that activate chloride secretion.

Administration, Oral↗
PubMed1998

The effects of post-weaning progestagen treatment (Regumate) of early-weaned primiparous sows on subsequent reproductive performance.

This study investigated the effects of feeding the orally active progestagen, altrenogest (Regumate) post-weaning on the subsequent reproductive performance of early weaned sows. Ninety (90) Large White/Landrace first parity sows were randomly assigned to three treatments. Treatment 1 (EW) and treatment 3 (CW) sows were weaned on day 12 and day 24 post-partum, respectively while treatment 2 sows (EW-R) were weaned on day 12 post-partum and received an individual daily dose of 20 mg of Regumate on days 13 to 24 post-partum inclusive. Each sow was mated naturally at least twice at the first post-weaning or post-treatment oestrus and slaughtered on days 25-28 of pregnancy to determine the number of corpora lutea and embryos. Regumate-to-oestrus and weaning-to-oestrus intervals were similar for EW-R and CW sows (6.2 vs. 5.6 days). However, both intervals were significantly shorter (P < 0.01) than the weaning-to-oestrus interval of EW sows (7.3 days). An excellent synchronization of oestrus was achieved with Regumate treatment with 97% of treated sows in oestrus within 7 days of Regumate withdrawal compared with 64% for EW sows (P < 0.01) and 87% for CW sows (P > 0.05). Treatment with Regumate resulted in a significant increase in ovulation rate (16.9 vs. 15.4 and 14.9 for treatments EW-R, EW and CW, respectively; P < 0.05) and a non-significant increase in early embryonic survival (77% vs. 68% vs. 68% for treatments EW-R, EW and CW, respectively; P > 0.05). These results indicate that Regumate feeding is a potential management tool to alleviate the diminished reproductive performance associated with early weaning regimes since it leads to successful control of oestrus, higher ovulation and embryo survival rates and thus a greater potential litter size.

Animals↗
PubMed2007

Use of N-terminal pro-brain natriuretic peptide to detect acute cardiac dysfunction during weaning failure in difficult-to-wean patients with chronic obstructive pulmonary disease.

OBJECTIVE: To evaluate the utility of serial measurements of plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) to detect acute cardiac dysfunction during weaning failure in difficult to wean patients with chronic obstructive pulmonary disease. DESIGN: Prospective observational cohort study. SETTING: A 14-bed general intensive care unit in a university hospital. PATIENTS: Nineteen patients mechanically ventilated for chronic obstructive pulmonary disease exacerbation who were difficult to wean. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Cardiac and hemodynamic variables, arterial and central venous blood gas, breathing pattern, respiratory mechanics, indexes of oxygen cost of breathing, and plasma levels of NT-proBNP were measured and analyzed immediately before (baseline) and at the end of a spontaneous breathing trial. Eight of 19 patients (42%) were identified with acute cardiac dysfunction at the end of the weaning trial. Baseline NT-proBNP levels were significantly higher (median 5000, interquartile range 4218 pg/mL) in these patients than in patients without evidence of acute cardiac dysfunction (median 1705, interquartile range 3491 pg/mL). Plasma levels of NT-proBNP increased significantly at the end of the spontaneous breathing trial only in patients with acute cardiac dysfunction (median 12,733, interquartile range 16,456 pg/mL, p < .05). The elevation in NT-proBNP at the end of the weaning trial had a good diagnostic performance in detecting acute cardiac dysfunction, as estimated by area under the receiver operating characteristic curve analysis (area under the curve 0.909, se 0.077, 95% confidence interval 0.69-0.98; p < .0001, cutoff = 184.7 pg/mL). CONCLUSIONS: Serial measurements of NT-proBNP plasma levels provided a noninvasive manner to detect acute cardiac dysfunction during an unsuccessful weaning trial in difficult to wean patients with chronic obstructive pulmonary disease. The utility of this test as a complement of the standard clinical monitoring of the weaning trial deserves further investigation.

Acute Disease↗
PubMed2004

Hypothyroidism and failure to wean in patients receiving prolonged mechanical ventilation at a regional weaning center.

OBJECTIVE: Hypothyroidism is cited as an uncommon cause of ventilator-dependent respiratory failure. The objective of this study was to determine the incidence of hypothyroidism in patients with respiratory failure, receiving prolonged mechanical ventilation (PMV) with failure to wean, referred to a regional weaning center (RWC) for weaning. SETTING: RWC. DESIGN: Retrospective. METHODS: Medical records were reviewed of 173 patients admitted to this RWC between January 1999 and March 2002. One hundred forty patients were noted to have had screening serum thyroid stimulating hormone (TSH) levels obtained at admission. Records of these patients were further evaluated. The following data were abstracted: age, sex, body mass index, serum TSH levels, number of patients with previously diagnosed hypothyroidism, and number of patients with hypothyroidism diagnosed clinically and by laboratory tests following admission to the RWC. Primary outcome was liberation from PMV, which was defined as being off ventilatory support for > 1 week. Univariate analysis was performed to determine relation between serum TSH levels and outcome; p < 0.05 was deemed statistically significant. RESULTS: Of 140 patients studied, 67 were male (48%) and 73 were female (52%), with a mean age of 66 + 15 years (+/- SD). Only one patient had a history of previously diagnosed hypothyroidism. A clinical diagnosis of hypothyroidism was made in 4 of 140 patients (3%) following admission. Serum TSH levels ranged from 0.19 to 121 mU/L in the studied subjects. Seventeen of 140 patients (12%) had elevated serum TSH levels. Serum tri-iodothyronine and/or thyroxine levels confirmed diagnosis of hypothyroidism in four of these patients (3%). Patients with newly diagnosed hypothyroidism were treated with thyroid supplements, and three patients were liberated from PMV while one patient died from other medical causes. Of the 140 patients, 92 patients (67%) were liberated from PMV while 48 patients (33%) could not be weaned. Mean serum TSH levels were 4.2 + 13 mU/L in the liberated patients and 4 + 4.7 mU/L in the patients who could not be weaned (p = 0.25). CONCLUSION: Hypothyroidism is an uncommon cause of failure to wean in patients receiving PMV (with an incidence of 3%). However, it is a potentially treatable cause and should be considered in all patients who fail to wean. Serum TSH level does not appear to affect successful weaning from PMV.

Comorbidity↗
PubMed1999

Influence of equine chorionic gonadotropin on weaning-to-estrus interval and estrus duration in early-weaned, primiparous, female swine.

The weaning-to-estrus interval (WEI) influences the total nonproductive days (NPD) accumulated by the breeding herd and affects herd productivity. Short lactation lengths (LL) are commonly followed by prolonged WEI, which are also associated with short estrus duration (ED). Equine chorionic gonadotropin treatment is a tool that has been used to reduce WEI, especially for low-parity females. The objectives for this study were to evaluate the effect of LL on the association between WEI and ED and to estimate the effects of postweaning eCG administration on WEI and ED for early-weaned females. Two treatments (TREAT) consisting of 750 IU of eCG (n = 96) or control (n = 77) were applied 1 d after weaning to first-parity, weaned females. The study was conducted on a commercial farm having a target LL of 18 d. Estrus detection was conducted three times daily, and estrus duration was determined as the interval between the first and the last positive response to back pressure. Analyses of variance were conducted to estimate the effects of LL and TREAT on WEI and the effects of TREAT and WEI on estrus duration. Mean LL was 17.9+/-1.7 d, mean WEI was 106.6+/-29.2 h, and mean estrus duration was 55.9+/-15.5 h. Even though the frequency of short WEI tended to increase with longer LL, mean WEI was shortest for females weaned after 18 d and longest for those weaned after 20 d (P<.05). The WEI for females receiving eCG (98.7+/-2.7 h) was shorter (P = .0001) than that for control females (121.5+/-3.3 h). The WEI was also affected by a LL x TREAT interaction (P = .0014), indicating that the interval was longer (P<.05) for control females weaned after 17 and 20+ d than for other females. The LL and TREAT did not affect estrus duration (P = .20 and P = .157, respectively). However, estrus duration was reduced as the WEI increased (P = .0001), and it was also influenced by a WEI x TREAT interaction (P = .024). A linear regression model estimated that the association between WEI and estrus duration was stronger in the eCG group than in the control group (R2 = .51 and .15, respectively; both P<.001). In conclusion, the use of eCG postweaning was associated with more precise prediction of estrus duration as a function of the WEI and allows optimization of breeding management in early-weaned, primiparous females.

Animals↗
PubMed1988

Morphine suppresses luteinizing hormone concentrations in transiently weaned sows and delays onset of estrus after weaning.

Lactating sows were used to evaluate effects of morphine and suckling on secretion of LH and prolactin (PRL) and occurrence of estrus after weaning. In the first experiment, crossbred multiparous sows nursing 7.9 +/- .4 pigs per litter at 25.2 +/- .3 d of lactation were subjected to one of three treatments during the middle 8-h segment of a 24-h experimental period. Treatments were infusion (i.v.) of morphine (200 mg/h) with the litter present (n = 4) or transiently weaned (n = 4), or transient weaning of litters without morphine (n = 4). Transient weaning decreased (P less than .05) prolactin and increased (P less than .05) the frequency of LH pulses and average concentration of LH. Infusion of morphine caused transient hyperthermia and suppressed (P less than .05) LH release in two of four sows nursing litters and in four sows whose litters were absent. Infusion of morphine, in the presence or absence of litters, suppressed PRL during the middle and last 8-h segments. A second experiment was conducted to test the hypothesis that chronic administration of morphine delays onset of estrus after weaning. Primiparous Duroc sows were assigned at weaning (53 to 63 d postpartum) to receive morphine (n = 10) or saline (n = 11). Saline (1.5 ml) or morphine (75 mg) was administered s.c. three times a day for 5 d after weaning. Onset of estrus after weaning was delayed in sows given morphine compared with those given saline (9.7 +/- .4 vs 5.2 +/- .3 d, respectively; P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Changes in the hypothalamic-hypophyseal-ovarian axis of primiparous sows following weaning or pulsatile gonadotropin releasing homrone administration and weaning.

Lactating primiparous sows were used to examine relationships among hypothalamic gonadotropin releasing hormone (GnRH), serum, and anterior pituitary gonadotropins and follicular development after weaning or after administering GnRH pulses (1.5 ug) once hourly for 72 h before weaning. Control sows were either slaughtered at 0 or 72 h after weaning or were cannulated for collection of blood samples until 24 h after estrus. Sows pulsed with GnRH were either slaughtered 72 h after beginning of GnRH treatment or were cannulated for collection of blood samples until 24 h after estrus. Exogenous GnRH pulsed hourly during 72 h prior to weaning stimulated follicular growth as demonstrated by an increase in number of surface follicles >5 mm in diameter and a decrease in number of follicles <5 mm in diameter. Interval (h) from weaning to an increase in estradiol (>16 pg/ml) was less in GnRH-pulsed than in control sows (P < 0.05), but hours from weaning to estrus were similar between groups. Amounts of GnRH in the medial basal hypothalamus (MBH), stalk median eminence (SME), and hypophyseal portal area (HPA) were similar among control sows killed at 0 or 72 h and sows pulsed with GnRH. Serum concentrations of luteinizing hormone (LH) and frequency of release of LH were similar between GnRH-pulsed and control sows, but concentrations of LH and follicle stimulating hormone (FSH) in anterior pituitary were lower in GnRH-pulsed sows than control sows. Administration of GnRH for 72 h prior to weaning in primiparous sows stimulated follicular growth as manifested by increased secretion of estrogen; however, the amount of follicular growth was apparently inadequate to hasten the onset of estrus after weaning.

Journal Article↗
PubMed2000

Relationships between individual behavioural traits and post-weaning growth in segregated early-weaned piglets.

Piglets' individual behavioural traits have been studied in the last decade but no report has linked these traits with growth. This experiment was conducted to determine if behavioural traits of segregated early-weaned piglets could be good predictors of their post-weaning growth and, thus, help to predict their adaptation to early weaning. Following segregated early weaning at 17+/-1 days old, 252 piglets were submitted to three tests between 20 and 25 days of age: open-field, reaction to humans and rank order based on competition for a restricted-access feeder. The body weight of each piglet was measured the day before weaning and once a week for the next 4 weeks. A principal component analysis yielded five factors with an Eigenvalue higher than 0.90 that accounted for 81% of the total variation between individuals: reaction to humans (25%), active response to stress (21%), passive response to stress (14%), feeding behaviour (10%) and rank order (9%). Passive reaction to stress was associated with better weight gain during the first week post-weaning (r=0.18; P=0.01), and a positive correlation was found between social status and weight gain during the 4 weeks following weaning (-0.15</=r</=-0.10); P</=0.10). No relation was found between reaction to humans and growth. These results confirm the relationship between rank order and growth in pigs and may suggest that reacting passively to stress could facilitate adaptation to weaning.

Journal Article↗
PubMed2000

Experimental models of porcine post-weaning colibacillosis and their relationship to post-weaning diarrhoea and digestive disorders as encountered in the field.

The aim of this study was to develop a reliable model system of porcine post-weaning colibacillosis, and in doing so to assess the primary relationship of enterotoxigenic Escherichia coli to post-weaning diarrhoea and digestive disorders as encountered in the field. Six sequential experiments were carried out using 168 SPF piglets weaned into an optimal controlled environment at 28 days of age. The piglets were allocated to 23 treatment groups, 17 of which were inoculated either orally or intragastrically with enterotoxigenic strains of E. coli (LT+, STI+, STII+) possessing adhesive factors including K88 (F4). The piglets were challenged either once (Day 4 post-weaning) or on several days post-weaning, with the challenge load for each inoculation varying from 10(8) to 10(12) CFU. Overall 14.5% of inoculated pigs developed severe illness and died: these had lesions in their digestive tracts typical of colibacillosis. Diarrhoea occurred on at least 1 day in 50% of inoculated pigs, but was transient (1.7 days on average), appeared very soon after challenge (sometimes within half a day), and was accompanied by signs of depression and low weight gain. Generally a prompt recovery then occurred. In the second 2 weeks post-inoculation daily weight gain reached the same level in most inoculated groups of pigs as in the uninoculated controls. Only a small number of pigs developed a chronic enteritis lasting several days, as is typically observed in field cases. Diarrhoea was more common in the piglets that were tested adhesive positive to the K88 fimbriae receptor, but the disorders were no more severe in these animals. The response of all pigs depended primarily on the inoculum used, and especially on the challenge load. Although enterotoxigenic E. coli are clearly important in the aetiology of post-weaning diarrhoea, other factors are also required for the production of the chronic post-weaning digestive disorders and ill-thrift that are commonly encountered in commercial piggeries.

Animals↗
PubMed1988

Pre-weaning supplementary feed and porcine post-weaning diarrhoea.

Attempts were made to induce an intestinal hypersensitivity response to weaner diet by feeding pigs with small quantities of this material before weaning. In two trials using different weaner diets piglets subjected to this regimen showed no significant differences in small intestinal structure, in ability to absorb xylose, in bodyweight gain, in incidence of diarrhoea or excretion of enteropathogens after weaning compared with pigs not given any of the diet before weaning, or fed with a different diet before weaning. When post-weaning diarrhoea occurred it was associated with an earlier, more prolonged and greater proliferation of enterotoxigenic Escherichia coli in the small intestines than occurred in healthy pigs after weaning. The greater proliferation in pigs which developed diarrhoea could not be attributed either to an excessive dietary intake after weaning, or to a specific proliferation of rotaviruses.

Animals↗
PubMed1997

The efficacy of enrofloxacin in-feed medication by applying different programmes for the control of post weaning oedema disease in weaned piglets.

Oedema disease (OD) usually occurs after weaning and is due to infection with (ETEEC) enterotoxaemic Escherichia (E.) coli. This study further examines the efficacy of three different in-feed usage programmes of enrofloxacin (ENR/Baytril I.E.R. 2.5%), on the control of post weaning OD in piglets. The recommended in-feed dosage of ENR for this clinical indication, i.e. 50 p.p.m., was used. Five groups with a total of 240 weaned piglets for 28 days period were used in this trial. One group (negative control) was offered feed free of antimicrobials, one group was offered feed as that of the negative control group except that the feed consumption was restricted for the first 12 days post weaning, and three groups were offered feed ad libitum medicated with 50 p.p.m. of ENR starting 7 days after weaning for 5, 7 and 10 days, respectively, and were compared with regard to their performance. Mortality was lower compared to the negative control group in all ENR treatments (P < 0.05). The evaluation of the growth performance data, as well as feed conversion ratio, indicated that the three treated groups performed remarkably better than the control group (P < 0.05). It was concluded that a strategic medication initiated 7 days post weaning with 50 p.p.m. of ENR and usually for a 10 day period is useful in controlling and/or preventing post weaning OD due to ETEEC.

Animal Feed↗
PubMed1995

[Ventilator weaning after long-term ventilation--the concept of a regional ventilator weaning center].

Long-term mechanical ventilation implies a significant number of weaning failures. The basis of this unweanability is chronic fatigue of the inspiratory muscles which is due to depletion of energy store (e.g. glycogen). Considering this pathophysiological principle, the decisive therapeutic option during weaning from long-term mechanical ventilation consists of resting the respiratory muscles. The commonly used assisted ventilation modes only partially relieve the respiratory muscles because the work of breathing is done both during the trigger phase and during the inspiratory cycle. The essential characteristic of our weaning concept includes the repeated determination of the spontaneous breathing frequency in awake patients, which is followed by controlled intermittent positive pressure ventilation with a slightly higher respiratory rate. Ideally, this results in total suppression of the activity of the breathing centre, and in subsequent relief and recovery of the respiratory muscles by replenishing the energy stores. The close succession of relief and training periods avoids inactivity-induced atrophy of the respiratory muscles and permits regeneration. Additionally, our weaning concept avoids increases in inspiratory work during the phases of spontaneous breathing. This means that high-resistance small-caliber endotracheal tubes have to be replaced by large tubes. Moreover, transtracheal oxygen insufflation during spontaneous breathing decreases anatomic dead space. This reduces minute ventilation and, therefore, the work of breathing. In patients still exhibiting chronic fatigue of the respiratory muscle pump after successful weaning, intermittent home ventilation is initiated via a breathing mask. Apart from the concept described above, successful weaning from the respirator after long-term ventilation is based upon dedicated patient care and depends on the architectural characteristics of the intensive care unit.

Breathing Exercises↗
PubMed1994

Weaning from prolonged mechanical ventilation. The experience at a regional weaning center.

STUDY OBJECTIVE: The aim of this study was to describe the facility, patient population, outcome of treatment, and survival of patients transferred to a regional weaning center (RWC) after prolonged mechanical ventilation in the ICU setting. DESIGN: Retrospective record review. SETTING: Regional weaning center. PATIENTS: Four hundred twenty-one consecutive ventilator dependent patients were transferred from ICU care for attempted weaning over a 36-month period. MEASUREMENT AND RESULTS: Acute catastrophic surgical, traumatic, or septic illness resulted in ventilator dependency with much greater frequency than decompensated COPD. Of the 421 patients, 116 died and 287 survived with outcome known at discharge. Of the 287 who survived, 212 were freed from ventilator support. Patients who weaned were ventilator-dependent for 46.9 +/- 2.9 days before transfer to the RWC. Almost half of those weaned were discharged to their homes. Survival at 6 months and 1 year after discharge was 44 percent and 28 percent respectively, and it was greater for those at home than for those discharged to an extended care facility (ECF). The RWC care was approximately $1,500 per patient day less costly than ICU care, and $208 per patient day less costly than noninvasive respiratory care unit care. CONCLUSIONS: Selected patients who become ventilator dependent for prolonged periods in the ICU may be transferred to an RWC with the expectation of successful weaning in a majority of cases.

Aged↗
PubMed1999

Production systems comparing early weaning to normal weaning with or without creep feeding for beef steers.

A 2-yr study was conducted to determine the effects of three weaning management systems on cow and steer performance. Cow-calf pairs were randomly assigned to one of three treatments, in which the steer calves were 1) early-weaned (yr 1, 177 +/- 9 d; yr 2, 158 +/- 21 d of age) and placed on a finishing diet (EW), 2) supplemented with grain for 55 d on pasture (yr 1, 177 to 231 d; yr 2, 158 to 213 d of age) while nursing their dams and then placed on a finishing diet (NWC), and 3) on pasture for 55 d while nursing their dams (yr 1, 177 to 231 d; yr 2, 158 to 213 d of age) and then placed on a finishing diet (NW). In yr 2, potential breed differences were evaluated using steers of three breed types: 1) Angus x Hereford (BRI); 2) Angus x Simmental (CON); and 3) Angus x Wagyu (WAG). In yr 1, EW steers gained 100% faster (P = .0001) than the average of NWC and NW steers, and NWC steers gained 32% faster (P = .02) than NW steers before weaning. In the feedlot, EW steers had lower intakes (7.70 vs 8.16 kg/d, P = .008) and better feed conversions (.170 vs .153, P = .002) than the average of NWC and NW steers. Marbling score was improved for EW steers compared with the average of NWC and NW steers (P = .003). In yr 2, EW steers had higher gains (P = .0006) during the entire study than the average of NWC and NW steers, and NWC steers had higher gains (P = .003) than NW steers. The EW steers had lower intakes (7.29 vs 7.68 kg/d, P = .0008) and better feed conversions (.160 vs .141, P = .0001) than the average of NWC and NW steers. The CON steers were heavier at slaughter than BRI steers (P = .01), and BRI steers were heavier than WAG steers (P =.0004). Early weaning improved the percentage of steers grading Average Choice or higher by 40%. The percentage of BRI steers grading Choice or greater was 21% higher and percentage of steers grading Average Choice or greater was 33% higher than CON. Cows with EW steers had higher ADG than cows with NW steers (.38 vs -.17 kg/d, P = .0001) before weaning. Cows with EW steers gained in body condition score (.23 vs .00, P = .04), and cows with NW steers did not change. Early weaning improved feed efficiency and quality grades of beef steers.

Animal Husbandry↗
PubMed2002

Effect of spray-dried plasma and lipopolysaccharide exposure on weaned pigs: II. Effects on the hypothalamic-pituitary-adrenal axis of weaned pigs.

A study was conducted with 20 weaned barrows (14 d, 4.98 +/- 0.21 kg) to determine the effect of feeding spray-dried plasma (SDP) after weaning on the pig's stress response to a lipopolysaccharide (LPS) challenge. After weaning, pigs were fed a diet containing 0 or 7% SDP for 7 d. On d 6 after weaning, all pigs were nonsurgically fitted with a jugular catheter. On d 7 after weaning, the pigs were given i.p. injections of either saline or LPS (150 microg/kg BW) followed by serial blood collection every 15 min for a 3-h period. Following the 3-h blood collection, all pigs were killed and tissue was collected for mRNA analysis. Pig weight on d 7 after weaning was not affected by dietary treatment (P > 0.21). Pigs fed the diet with SDP had lower (P < 0.05) levels of hypothalamic corticotropin-releasing hormone (CRH) mRNA, pituitary gland CRH receptor mRNA, and adrenal gland adrenocorticotropin-releasing hormone (ACTH) receptor mRNA. Dietary treatment did not affect pituitary gland proopiomelanocortin (POMC) mRNA. No effect of LPS treatment was observed in any of the mRNA levels examined. For both serum ACTH and cortisol, there was a significant diet x LPS treatment interaction (P < 0.01) such that both the ACTH and cortisol responses to the LPS challenge were greater in the pigs fed the diet with SDP than in the pigs fed the diet without SDP. For pigs given the saline injection, diet did not affect basal serum cortisol concentration; however, basal serum ACTH concentration was lower in those pigs fed the diet with SDP (P < 0.0001). A diet x LPS treatment interaction (P < 0.024) was observed for adrenal gland mRNA expression for steroidogenic acute regulatory (StAR) protein such that the LPS-induced increase in StAR mRNA was greater in the pigs fed SDP than in pigs fed the diet without SDP. These results demonstrate that pigs fed a diet with SDP have an increased activation of the pituitary-adrenal axis following an LPS challenge compared to pigs fed a diet without SDP.

Animals↗