Hormonal response to dietary L-arginine supplementation in heat-stressed sows

The response of key metabolic hormones to dietary arginine supplementation in heat-stressed lactating sows was determined. Sixty-three sows were exposed to a thermoneutral (TN = 20°C) or hot (HT = 29.4°C) environmental temperature, and were fed diets containing 0.96% (control, C), 1.34% (medium, ME) or 1.73% (high, HI) arginine. Blood samples were obtained 2 h postprandially on days 7, 14, and 21 of lactation and concentrations of insulin, glucose, growth hormone (GH) and prolactin were determined. Arginine supplementation increased insulin concentrations (P < 0.01) on day 14 of lactation, had no effect (P > 0.1) on glucose, and decreased (P < 0.05) GH with ME compared with C diets. There was a temperature × diet interaction (P < 0.05) for prolactin, with values being greater for the C compared with the ME and HI diets at 29.4°C, but being lower at 20°C.There was no effect (P > 0.1) of temperature alone on any of the measured variables. Results indicate that arginine supplementation may mediate improvements in nutrient utilization by regulating the metabolism of both insulin and GH in lactating sows. Key words: Arginine, growth hormone, heat stress, insulin, lactation, prolactin, sow

Colostrum production in swine: from the mammary glands to the piglets

Abstract

An early and high intake of colostrum is a major determinant of survival during the early suckling period, when most losses occur. Indeed, piglets are born devoid of body fat and are dependent on colostrum as their sole energy source. Colostrum also has other essential roles for the developing piglet; most importantly, it provides passive immunity and nutrients to the piglet and permits thermoregulation. It also stimulates gastrointestinal development, muscle protein synthesis and the development of active immunity. Neonatal swine can efficiently use colostrum since they have a remarkable capacity to deposit large amounts of fat and can also absorb intact immunoglobulins for 24 h postnatally. The production of colostrum, however, is very variable between sows and the factors affecting this variability are not well known. Such studies are most difficult to carry out since it is not easy to estimate colostrum yield. Indeed, the various methods that can be used tomeasure colostrum yield all have several drawbacks. The endocrine status of the sow undoubtedly affects the process of colostrogenesis and the underlying mammary changes associated with it. The composition of sow colostrum is well known, yet it is only recently that the presence of numerous bioactive compounds which can either protect piglets from infection or modulate their metabolism was detected in colostral secretions. There are indications that the composition of colostrum can be altered by some management components but further studies are necessary in that area.

Joint working with hospice teams: a renal collaborative approach

There are over 600 million people in the world aged 60 years and over. This figure is expected to double by 2025 and to reach 2 billion by 2050 (1). Population ageing is characteristically accompanied by an increase in the burden of chronic non-communicable diseases such as diabetes, cardiovascular disease, cancers and renal failure. As a consequence, pressures on health systems worldwide will increase (1). Data produced by the National Renal Workforce Planning Group in 2002 (2), predicted that the demand for renal replacement therapy (RRT) will continue to rise beyond 2010 for many reasons one of those being demographic changes with an aging population. This will also have an impact on the numbers of patients predicted to commence dialysis and transplantation (Table 1). With this higher projection of patients requiring RRT, there is a need to look at new ways of working.

Effects of prolactin inhibition during late gestation on the immunity of gilts and foetuses

The goal of the present study was to determine the effects of inhibiting prolactin (PRL) synthesis for three consecutive 20-d periods during the second half of gestation, on the immune status of gilts and their foetuses. Crossbred gilts were randomly assigned as controls (n = 12) or received 10 mg of bromocriptine orally three times daily from days 50 to 69 (BR50, n = 12), days 70 to 89 (BR70, n = 12), or days 90 to 109 (BR90, n = 12) of gestation. All gilts were injected subcutaneously with ovalbumin (OVA) on days 53 and 72 of gestation. Blood samples were collected on days 50, 60, 70, 90 and 109 of gestation to evaluate the antibody response. Cellular immunity, as measured by lymphocyte proliferative response and production of interferon-γ, was characterized on controls and BR50 gilts until the end of gestation. Six foetuses from five litters per treatment were selected and their thymus and spleen were excised and weighed. Splenocytes and thymocytes were assayed to characterize lymphocyte sub-populations and to evaluate splenocyte responses to mitogenic stimulation. Average spleen weight in foetuses from BR90 gilts was significantly lower (P < 0.05) than that of foetuses from control or BR70 gilts. In all gilts treated with bromocriptine,percentages of CD4+ and CD8+ lymphocyte populations in foetus spleens were numerically reduced compared with those obtained in foetus from control gilts but the differences were not significant. In BR50 gilts, inhibition of PRL synthesis did not affect the proliferative response of lymphocytes to mitogenic stimulations compared with control group, but tended (P = 0.13) to increase the production of interferon-γ. A time effect showed that production of interferon-γ by leukocytes was reduced (P < 0.02) on days 80 and 100 compared with days 50 and 70, regardless of bromocriptine treatment. The antibody response of gilts to OVA was not affected by bromocriptine treatments. In conclusion, inhibition of PRL synthesis by bromocriptine did not significantly affect immune response of pregnant gilts. In foetuses, although the differences between treatments were not significant, data suggest that the foetal development of immune tissues seems to be impaired by bromocriptine treatment. Key words: Bromocriptine, prolactin, immunity, pregnancy, sow

Impacts of dietary protein level and feed restriction during prepuberty on mammogenesis in gilts

The possible roles of dietary protein level and feed restriction in regulating mammary development of prepubertal gilts were investigated. Cross-bred gilts were fed a commercial diet until 90 d of age and then divided into four nutritional regimens based on two pelleted diets (as-fed basis): a high-protein diet (HP = 13.8 MJ of ME, 1.0% total lysine, 18.7% CP) and a low-protein diet (LP = 13.8 MJ of ME, 0.7% total lysine, 14.4% CP). Nutritional regimens were as follows: 1) HP ad libitum until slaughter (n = 22, T1); 2) HP ad libitum until 150 d of age followed by LP until slaughter (n = 20, T2); 3) LP ad libitum until slaughter (n = 21, T3); and 4) HP with a 20% feed restriction until slaughter (n = 19, T4). Gilts were weighed, their backfat thickness was measured, and jugular blood samples were obtained on d 90, 150, and at slaughter to determine concentrations of prolactin, IGF-I, leptin, and glucose. Gilts were slaughtered 8+/-1 d after their first or second estrus (202.7+/-14.5 d of age). Mammary glands were excised, parenchymal and extraparenchymal tissues were dissected, and composition of parenchymal tissue (protein, fat, DM, DNA, protein/DNA) was determined. The T4 gilts weighed less (P < 0.01) and had less backfat (P < 0.01) than did gilts on other treatments on d 150 and at slaughter. Treatments had no significant effects on prolactin, IGF-I, or glucose concentrations, but there was a treatment x day interaction (P < 0.01) for leptin, with concentrations being lower at slaughter in restricted-fed (T4) vs. LP (T3) gilts (P < 0.05). There was less extraparenchymal mammary tissue (P < 0.01) in T4 gilts than in gilts from the other groups and a tendency (P = 0.13) for the amount of parenchymal tissue to be lower in T4 gilts. In conclusion, a lower lysine intake during prepuberty did not hinder mammary development of gilts, but a 20% feed restriction decreased mass of parenchymal and extraparenchymal tissues. The effect of feed restriction on extraparenchymal tissue is most likely associated with the lower fat deposition.

Growth-hormone-releasing factor given to early-pregnant Genex-Meishan and Large White gilts: Effects on growth, carcass, meat quality and histochemical traits of the progeny

The objective of this study was to determine the effects of growth hormone-releasing factor (GRF) given in early gestation on post-weaning performance, carcass and meat quality and histochemical properties of two pig genotypes. Large White (LW, n = 10) and Genex Meishan-derived dam line (GM, with 50% Meishan genes, n = 10) gilts were treated during gestation with either saline injections (control, n = 5 LW and 5 GM), or 6.6 µg kg-1 of a GRF analog (n = 5 LW and 5 GM), given thrice daily from days 18 to 33 of gestation. After birth, at 56 d of age, four piglets (two barrows and two gilts) each from 20 litters were selected, allotted into individual pens and grown to slaughter weight (108.2 ± 2.3 kg). Feed intake was measured daily and pigs were weighed weekly. Prenatal GRF treatment had a detrimental effect (P < 0.05) on daily gain in both genotypes, but did not affect carcass quality. Significant interactions between GRF, genotype and sex (P < 0.01) for colour traits of the longissimus (L) and semimembranosus (SM) muscles and between GRF and genotype (P < 0.01) for shear force of the L muscle were found. GM pigs had lower growth rate (P < 0.01), higher feed intake (P < 0.05), fatter and shorter carcass (P < 0.001) than LW. L and SM muscles from GM pigs were less exudative (P < 0.05) than LW. L muscle from LW had higher percentages of slow oxidative (SO) (P < 0.001) and fast oxidative glycolytic (FOG) (P < 0.01) fibres but lower percentage of fast glycolytic (FG) fibres (P < 0.001) than that of GM. The results suggest that GRF given in early lactation reduces post-weaning growth of pigs from either breed, but does not affect carcass quality. GM pigs have poorer carcass quality than LW. Key words: Gestating gilts, growth hormone releasing factor, growth, carcass characteristics, meat quality traits, muscle fibre, pig

Gene expression of leptin, leptin receptor, prolactin receptor and whey acidic protein in mammary glands of late-pregnant gilts from two breeds

In order to identify genes which are essential for pig mammary gland development, mRNA levels of prolactin receptor (PRL-R), leptin, leptin receptor and whey acidic protein (WAP) were measured in parenchymal tissue of 110-d-pregnant gilts. Thirteen Upton-Meishan (UM) and 14 Large White (LW) pregnant gilts and 5 non-pregnant control gilts (2 LW and 3UM) were used. PRL-R and WAP mRNA levels were higher in pregnant than in non-pregnant gilts (P < 0.05). Leptin mRNA levels were higher in UM than in LW gilts (P < 0.05), but this breed effect was not seen when leptin mRNA levels were corrected for percent fat in parenchyma. Correlations were found between concentrations of IGF-I in plasma and PRL-R (P < 0.01) and WAP (P < 0.05) mRNA levels in UM gilts. Serum prolactin (PRL) was correlated with leptin mRNA levels in the overall (P < 0.05) and LW (P < 0.05) populations of gilts, while estradiol was associated with leptin receptor mRNA in UM gilts (P < 0.05). The mRNA levels of all studied genes were positively correlated with mammary parenchymal and extra parenchymal weights in UM gilts, whereas these variables were only correlated with PRL-R and WAP gene expression in LW gilts. The presence of leptin and leptin receptor mRNA in parenchymal tissue suggests a paracrine role for leptin in mammary tissue of late-pregnant gilts. These results also suggest that the PRL signalling pathway is fully active at the transcriptional level in the mammary gland of gilts at 110 d of pregnancy. Key words: Genetics, pig, mammary glands, Meishan, mRNA

Use of recorded nursing grunts during lactation in two breeds of sows. I. Effects on nursing behaviour and litter performance

The impact of exposing lactating sows and their litters to recorded sow nursing grunts played at different intervals during lactation was studied. Yorkshire × Landrace (YL) and 25% Meishan (MH) primiparous sows were divided into three groups (n = 14): (1) no playback, (2) playbacks at 35-min intervals (GR35), and (3) playbacks at 40-min intervals (GR40). Recordings were played from day 110 of gestation to day 27 of lactation. Nursing behaviours, incidence of nursings without milk ejection (NPN), nursing interval and proportion of nursings induced by playbacks were measured on days 6, 18 and 26 of lactation. Litter size was standardized to 10 ± 1 piglets within 48 h of birth and piglets were weighed weekly. Mean nursing intervals, excluding NPN, were shorter for MH than for YL sows (P < 0.001). The increase in mean nursing interval between days 6 and 18 was greater in GR40 than in GR35 or controls (P < 0.01) and, when excluding NPN, the mean nursing interval decreased in GR35 on day 18 (P = 0.01). The occurrence of NPN decreased as lactation advanced (P < 0.001) and was lower for MH than YL sows on day 26 (P < 0.001). Between days 6 and 18, the proportion of nursings initiated by playbacks increased (P < 0.05) and the duration of milk ejection decreased (P < 0.001). In MH sows, controls had longer milk ejections than GR35 (P < 0.05) whereas, in YL sows, controls had shorter milk ejections than GR40 (P < 0.05) and GR35 (P = 0.06). Piglet growth was not affected by treatments or breed (P > 0.1). In conclusion, exposing sows and their litters to recorded sow nursing grunts played at 35-min intervals reduced nursing intervals on day 18 of lactation only, without affecting piglet performance. Key words: Auditory stimulus, behaviour, lactation, litter performance, Meishan, sows

Use of recorded nursing grunts during lactation in two breeds of sows. II. Effects on sow performance and mammary development

Primiparous lactating sows of two different genotypes [42 Genex-Meishan hybrid (MH) and 42 Yorkshire-Landrace (YL)] were exposed to recorded nursing grunts played at different intervals, and the effects on sow performance and mammary growth were studied. Sows within each breed were divided in three groups (n = 14 for each group): (1) no playbacks (control), (2) playbacks at 35-min interv als (GR35), and (3) playbacks at 40-min intervals (GR40). Recordings were played from day 110 of gestation to day 28 of lactation. Litter size was standardized to 10 ± 1 pigs within 48 h postpartum, and weight and backfat thickness of sows were recorded on day 110 of gestation, and on days 2 and 27 of lactation. Sow feed and water intakes were recorded throughout lactation. Milk samples were obtained from all sows on day 27 postpartum and jugular blood samples were obtained on day 28 for measurement of IGF -I and prolactin concentrations. Sows were slaughtered on day 28 of lactation and their mammary glands were excised to perform compositional analyses. Ovaries were also collected. The MH sows weighed less (P < 0.01) and had more backfat (P < 0.01) than YL sows. Milk from MH sows contained more dry matter (P < 0.05) and more lactose (P < 0.05) than that from YL sows. Mammary parenchymal tissue weighed less (P < 0.05) and contained less total protein (P = 0.01) and total DNA (P < 0.01) in MH than in YL sows. Sows in GR35 also had more total parenchymal DNA (P < 0.05) than control sows. Circulating concentrations of IGF-I and prolactin were not affected by breed or treatment (P > 0.1) whereas ovaries were heavier (P < 0.01) in control MH than in control YL ows. Therefore, playbacks of nursing grunts at 35-min intervals throughout lactation increased total mammary cell number without affecting hormonal or milk composition status. Key words: Auditory stimulus, lactation, mammary development, Meishan, milk, sows

Effect of lead exposure on spatial learning and running speed in the short-tailed opossum, Monodelphis domestica (Didelphidae)

Studies were conducted to assess the spatial learning ability in adult males of the short-tailed opossum, Monodelphis domestica using a T-maze, complex maze and elevated radial 8-arm maze. This is the first study of maze learning in opossums. In the T-maze, the performance of these animals improved over an 8-day training period. Eighty percent of the subjects initially trained to turn to the right for food reinforcement reached criterion (80% correct responses) by day 3 and all reached criterion by day 4. Reversal training (subjects then trained to turn to the left) was more difficult and required 8 days for all subjects to reach criterion. In the complex maze, 89% of the animals achieved the criterion level of performance (3 consecutive trials with 5 or fewer errors) on the eighth day of training and all reached criterion by day 10. The relative importance of intramaze vs. extramaze cues in directing choice behavior was investigated in the radial arm maze. A discrimination procedure was used which selectively rewarded subjects for following only one set of cues. Animals in the intramaze group obtained a food pellet from a cup at the end of each arm. In the extramaze group, the food cups were placed on a small platform just beyond the end of each arm. All subjects were initially trained to visit each arm with the maze in a fixed position (controls) and did so within 15 test sessions. Following these initial trials, the maze was rotated to a different position after each choice. For subjects in the intramaze group, the food moved in conjunction with the rotation of the arms thereby increasing the relevance of intramaze cues. In the extramaze group, extramaze cues became more important because the food remained on the platforms in the same position in the room. Animals in the extramaze group performed significantly better than chance whereas the intramaze subjects did not. This indicates that intramaze cues are not as important as extramaze cues for accurate choice behavior in this marsupial. In addition, animals injected with tetraethyllead showed a significant impairment in running speed and T-maze learning ability as compared to saline-injected controls.

Endocrinology and mammary development of lactating Genex-Meishan and Large White sows

Endocrine and metabolic data as well as mammary tissue composition were obtained in Genex-Meishan (GM, containing 50% Chinese Meishan genes) and Large White (LW) lactating sows. Jugular vein cannulae were used to collect serial blood samples from 9 LW and 8 GM sows for 4 h every 15 min on days 6 and 19 of lactation. Concentrations of prolactin and cortisol were determined on all samples while those of insulin-like growth factor-I (IGFI), growth hormone (GH), glucose and free fatty acids (FFA) were measured in hourly samples. Milk samples were obtained from 19 GM and 16 LWsows on day 23 of lactation and all sows were slaughtered on day 25. Mammary glands were excised and analyzed for tissue composition and for number and affinity of prolactin receptors. Concentrations of plasma IGF-I were lower (P < 0.01) and plasma FFA greater (P < 0.001) in GM than in LW sows. On day 6 of lactation, serum prolactin (P < 0.05) and cortisol (P < 0.01) concentrations were greater and glucose values lower (P < 0.001) in GM than in LW sows. The concentration of IGFI in lactoserum was lower (P < 0.001) while that of prolactin was greater (P < 0.05) in GM compared to LW sows on day 23 of lactation. There was less (P < 0.001) residual milk and more (P < 0.05) parenchymal RNA in mammary glands from GM compared to LW sows. The affinity of prolactin receptors was also greater (P < 0.05) in GM than in LW sows. The better emptying of mammary glands by litters from GM sows and the greater circulating concentrations of prolactin in early lactation as well as the greater affinity of mammary prolactin receptors may be related to the great milking potential of Meishan-derived sows. Key words: Hormones, lactation, mammary gland, Meishan, prolactin, sows

These studies were conducted to assess the effects of lead toxicity on exploratory behavior and running. Effects of lead on exploratory behavior and running speed in the shrew, Blarina brevicauda (Insectivora)

These studies were conducted to assess the effects of lead toxicity on exploratory behavior and running speed in the short-tailed shrew, Blarina brevicauda. Shrews from the experimental group received 25 mg/kg/day of lead acetate in their drinking water for a period of 90 days. Control subjects received sodium acetate. Exploratory behavior was determined using a computerized activity chamber where movements of test subjects broke infrared beams projected onto the floor of the apparatus. Time spent (sec) in exploration was recorded over eight 6-min intervals. Running speed (km/hr) was measured in a microprocessor-controlled rectangular racetrack fitted with photocell timers. With respect to time spent in exploration, there were significant differences between lead-exposed (20.5-23.9 sec per 6-min testing session) and control subjects (6.8-8.1 sec) after the sixth testing interval in the activity chamber. With respect to maximal running speed, control subjects ran significantly faster (mean: 14.8 km/hr) than their lead-exposed counterparts (5.83 km/hr). Lead-exposed animals exhibited hyperactivity and increased random locomotor movements. They would frequently bump into the walls and their movements were more random. Controls typically ran along the racetrack in a straight line. These results represent the first data for the effects of lead exposure on exploratory behavior and running speed for shrews.

Effects of GRF in early gestation on foetal development in Large White and Genex-Meishan gilts

The effects of growth hormone-releasing factor (GRF), given in early gestation, on reproductive traits, foetal development and pre-weaning growth of piglets from two breeds were studied. Large White (LW, n = 26) and Genex-Meishan (GM, containing 50% Meishan genes, n = 37) pregnant gilts were divided in two groups: (1) saline injections (n = 33) and, (2) injections of 6.66 µg kg-1 of a GRF analogue (n = 30), given thrice daily from days 18 to 33 of gestation. Jugular blood samples were collected on days 17, 34 and 109 of gestation and were assayed for various hormones and metabolites. Thirty-six gilts were slaughtered on day 110 of gestation and uterine, foetal and placental measurements were obtained. The other 27 gilts farrowed. There was a day × treatment interaction (P < 0.001) for glucose, insulin, free fatty acids (FFA) and insulin-like growth factor I (IGF-I), with values being greater on day 34 in gilts receiving GRF. The increase in insulin concentration was greater in LW- than in GM-treated gilts (P = 0.02). Exogenous GRF increased foetal weight in LW litters only (1.13 ± 0.04 vs. 1.05 ± 0.03 kg; P = 0.04) whereas fat content of carcasses tended to be lower only in foetuses of treated GM gilts (5.3 ± 0.2 vs. 5.8 ± 0.2%; P = 0.1). Weight of the longissimus muscle and its fibre number were not influenced by GRF. Furthermore, growth of piglets to 28 d was not affected by GRF treatment (P > 0.1). In conclusion, GRF given in early gestation seems to have different effects in LW and GM litters, yet it does not alter pre-weaning growth rate. Key words: Molybdenum, molybdenosis, copper, mine tailings, reclamation, animal health

Specific window of prolactin inhibition in late gestation decreases mammary parenchymal tissue development in gilts

Prolactin is required from d 70 to 110 of gestation for normal mammary development of gilts. The goal of the present study was to determine the effect of inhibiting prolactin with bromocriptine during specific time windows during the second half of gestation on mammary gland development in gilts. Crossbred primigravid gilts were assigned as controls (n = 12) or received 10 mg of bromocriptine orally three times daily from d 50 to 69 (BR50, n = 12), d 70 to 89 (BR70, n = 12), or d 90 to 109 (BR90, n = 12) of gestation. Jugular blood samples were collected on d 50, 70, 90, and 109 of gestation and assayed for prolactin and estradiol. Gilts were slaughtered on d 109 of gestation and fetuses were counted and weighed. One row of mammary glands was used for dissection of parenchymal and extraparenchymal tissues, and for biochemical analyses. Tissue from the other row was used for measures of prolactin receptor number and affinity. Concentrations of prolactin were decreased markedly (P < 0.001) at the end of each bromocriptine treatment period compared with controls, but there was no overall treatment effect (P > 0.1) on estradiol concentrations. Extraparenchymal tissue weight of the mammary glands was unaffected by treatments (P > 0.1), but weight of parenchymal tissue, total DNA, and total RNA were lower (P < 0.01) in BR90 than control gilts. The percentage of DM in parenchymal tissue was unaffected by treatments (P > 0.1), but percentage of fat was higher and percentage of protein lower (P < 0.01) in BR90 gilts compared with controls. Cell size, as estimated by the protein:DNA ratio, also was lower (P < 0.01) in the BR90 group. Number and affinity of prolactin receptors in parenchymal tissue were not significantly altered by treatments. In conclusion, there is a specific time period in the second half of gestation, from 90 to 109 d, during which prolactin is essential for normal mammary parenchymal tissue development.

Glucose and hormonal profiles of Meishan-derived and Large White gilts in early and late gestation

Jugular catheters were inserted non-surgically in eight Large White (LW) and nine Genex-Meishan (GM, with 50% Meishan genes) gilts on days 37 and 106 of gestation to obtain serial blood samples on days 38 and 107. Meal time was 0805. Three preprandial samples (baseline) were obtained at 0740, 0750 and 0800 as well as samples every 20 min thereafter until 1100. Glucose and insulin concentrations were measured in all samples and values for cortisol and insulin-like growth factor-I (IGF-I) were determined on preprandial samples and hourly samples thereafter. All gilts were weighed and their backfat thickness measured at mating and on days 17, 34 and 109 of gestation. Gilts of the GM line were lighter (P = 0.03) and fatter (P = 0.004) than LW. Postprandial values for cortisol and IGF-I were greater in GM than LW gilts in early gestation only (P < 0.05). The same was true for baseline IGF-I (P < 0.001). Postprandial insulin was not affected by breed or stage of gestation (P > 0.1), yet glucose values were greater in LW than in GM gilts (P < 0.05) and postprandial glucose was greater in late compared to early gestation in both breeds (P < 0.001). In conclusion, both cortisol and IGF-I concentrations varied differently between genotypes depending on the stage of gestation. Furthermore, even though postprandial insulin was not affected by breed, concentrations of glucose were lower in GM gilts. A metabolic adaptation to gestation was observed in both breeds, with glucose values increasing in later gestation. Key words: Meishan, Gestation, Pigs, Hormones, Insulin, Glucose

Expression levels of STAT5A and STAT5B in mammary parenchymal tissue from Upton-Meishan and Large White gilts

The implication of STAT5A and STAT5B in mammary gland development and maintenance of lactation is well documented in rodents and humans. However, little is known regarding their roles in mammary gland development during gestation in pigs. We identified and analyzed the complete coding sequences of swine STAT5A and STAT5B and evaluated their mRNA levels in mammary glands of gestating gilts (day 110) in two different breeds, Upton-Meishan and Large White. Sequence analysis revealed a new APASA insertion in the STAT5A amino acid sequence that is in close proximity to residue Tyr 699 and whose phosporylation leads to the activation of target genes’ transcription. STAT5A mRNA levels were higher in Upton-Meishan than in Large White. In both breeds, STAT5B mRNA levels were higher than those of STAT5A , which is contrary to what was found in other mammals. A correlation between circulating IGF-I levels and STAT5B mRNA levels in the mammary gland was noticed in the Upton-Meishan breed only. STAT5B mRNA levels in mammary tissue of Large White gilts were highly correlated with extra-parenchymal tissue weight, parenchymal tissue weight, total parenchymal DNA, RNA and RNA/DNA ratio. In Upton-Meishan gilts, correlations were observed only between extra-parenchymal weight and STAT5A and STAT5B mRNA levels. These results indicate that there are significant differences in mRNA levels of STAT5A and STAT5B in the mammary glands of pregnant gilts when compared to other mammals, and between swine breeds. Key words: Mammary glands, signal transducers, pregnancy, kinases, pig, expression

Huntington's disease: a randomized, controlled trial using the NMDA-antagonist amantadine

OBJECTIVE

To examine the acute effects of the NMDA receptor antagonist amantadine on motor and cognitive function in Huntington's disease (HD).

BACKGROUND

Chorea in HD and in the levodopa-induced dyskinesias of PD may be clinically indistinguishable. In PD, hyperphosphorylation of NMDA receptors expressed on striatal medium spiny neurons contributes to peak-dose dyskinesias, and drugs that block these receptors can diminish chorea severity. Because these spiny neurons are the primary target of the neurodegenerative process in HD, sensitization of NMDA receptors on residual striatal neurons might also participate in the generation of motor dysfunction in HD.

METHODS

To evaluate this possibility, 24 patients with HD entered a double-blind placebo-controlled crossover study of amantadine with two 2-week arms.

RESULTS

Chorea scores were lower with amantadine (usually 400 mg/d) than placebo, with a median reduction in extremity chorea at rest of 36% (p = 0.04) for all 22 evaluable patients and of 56% in the 10 individuals with the highest plasma drug levels. Improvement correlated with plasma amantadine concentrations (p = 0.01) but not CAG repeat length. Parkinsonian rating scores did not worsen and there was no consistent change in cognitive measures. Adverse event profile was benign.

CONCLUSIONS

Results suggest that NMDA receptor supersensitivity may contribute to the clinical expression of choreiform dyskinesias in HD and that selective antagonists at that site can safely confer palliative benefit.

Hormonal response of pregnant gilts fed a high fiber or a concentrate diet once or twice daily

The effects of fiber intake and feeding frequency on endocrine status were studied. Gilts were fed 2.2 kg d-1 of a concentrate diet (n = 6; 5.3% crude fiber) or 3.1 kg d-1 of a high-fiber diet (n = 7; 18.2% crude fiber) as of day 23 of gestation. For a 1-mo period, starting on day 60 of gestation, three or four animals within each dietary treatment received one daily ration at 0800 h while the others received two meals at 0800 and 1430 h. Feeding frequency was then reversed for the following 1-mo period. Jugular catheters were inserted on day 23 of each 1-mo period and serial blood samples were obtained from 0730 to 1630 h on day 25, to measure cortisol, insulin, glucose and free fatty acids (FFA). The mean of three samples obtained before the morning or afternoon mealtime was used to establish a preprandial baseline and samples thereafter were used to measure area under the curve (AUC) and maximal values. Fiber intake had no effect on any baseline values (P > 0.1), but decreased overall insulin AUC (P < 0.05) and glucose maximal values (P < 0.05) and increased morning FFA AUC (P < 0.05). Compared to one daily meal, twice daily feeding increased afternoon baseline cortisol (P < 0.05) and decreased morning cortisol AUC and baseline FFA (P < 0.001). It also increased afternoon insulin maximal values and AUC (P < 0.05) as well as morning and afternoon maximal glucose (P < 0.05) and decreased morning maximal FFA (P < 0.05). Insulin was the only variable affected by the fiber intake × number of meals interaction with twice daily feeding lowering morning maximal (P < 0.05) and AUC (P < 0.001) values in concentrate-fed gilts while not altering those values in gilts fed a high-fiber diet. Addition of fiber to the diet of pregnant gilts altered their hormonal response to meals, while once daily feeding created a post-absorptive state in the morning and increased cortisol concentrations postprandially. Key words: Gestation, pigs, fiber intake, feeding frequency, insulin, glucose

Lactational performance, nursing and maternal behavior of Upton-Meishan and Large White sows

The growth of litters from 19 Upton-Meishan (UM) and 16 Large White (LW) sows was recorded from birth to weaning (25 d of age). Water and feed intake of sows were recorded. Suckling behavior was studied on days 5 and 20 of lactation. Milk yield was measured on day 22 and a milk sample was obtained the next day. Water intakes were similar (P = 0.947) for both breeds, yet UM sows consumed less feed throughout lactation (P = 0.0002). Average piglet (P < 0.05) and total litter (P < 0.001) weights were greater as of day 7 in UM compared to LW sows. Mean piglet weight on day 24 was 6.13 ± 0.16 kg for UM litters and 5.33 ± 0.33 kg for LW litters. Suckling interval was similar for UM and LW litters on day 5 (P = 0.533), but was shorter for UM litters on day 20 (41.4 ± 1.2 vs. 48.3 ± 2.8 min; P= 0.060). On day 22, daily milk yield corrected for actual suckling interval was greater (10.59 ± 0.47 vs. 8.03 ± 0.65 kg; P = 0.003) in UM sows. Milk from UM sows contained more fat (P= 0.042) and lactose (P = 0.005). In conclusion, the greater growth rate of piglets from UM sows is mainly due to a higher frequency of nursings and to greater energy content of milk. Key words: Sows, lactation, breed, Meishan, behavior, nursing

A brief analysis of clinical pharmacy interventions undertaken in an Australian teaching hospital

Selected clinical pharmacy interventions undertaken during a 30-day data capture period were analysed, seeking to gain a greater understanding of the nature of the drug-related problems involved. Pharmacists were asked to record only interventions that were of potentially major significance. A total of 67 interventions were submitted for analysis. In 28 cases (41.7% of the initial total) the intervention reports were excluded from further analysis after initial review. For the remaining 39 interventions, 20 patients (51%) were under the care of a medical unit, and cardiovascular/antithrombotic agents accounted for 17 reports (43.5%). The majority of interventions were implemented at the time of inpatient medication order review by the clinical pharmacist (n=25, 64%). The most common category of drug-related problem addressed in the interventions related to the prescription of inappropriately high doses of the correct drug for the patient (n=17, 43.6%). Deficiencies in technical knowledge accounted for less than 25% of all cases.