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Biomedical subjects

M A Sutherland

Publications and source records attributed to M A Sutherland.

12 recordsLinked to original sources
PubMed2007

Immune responses of piglets to weaning stress: impacts of photoperiod.

An acute stress response can be provoked by abrupt social, nutritional, and environmental changes associated with weaning, and this may disrupt homeostasis and thus compromise well-being. Manipulating environmental factors, such as photoperiod, might provide a simple way to reduce the physiological consequences that piglets experience due to weaning stress. The objective of this study was to evaluate the impacts of photoperiod manipulation across various weaning ages on leukocyte populations, lymphocyte proliferation, natural killer cytotoxicity (NK), chemotaxis, phagocytosis, and immunoglobulin G, cortisol, and BW of piglets during the nursery phase. Sixty-eight crossbred piglets were obtained from sows kept on a short-day (8 h of light/d) photoperiod from d 90 of gestation until weaning. Piglets were weaned at 14, 21, or 28 d of age and kept on a short or long (16 h of light/d) photoperiod until 10 wk of age. Piglet BW and blood samples were collected at weaning and at 6, 8, and 10 wk of age. Pigs weaned at 28 d had reduced neutrophil counts (P < 0.001), phagocytosis (P < 0.001), and lymphocyte proliferation (P < 0.05) at weaning compared with those weaned at 14 and 21 d. Pigs weaned at 21 d tended to have lower (P = 0.08) lymphocyte counts than did pigs weaned at 14 or 28 d. Pigs weaned at 14 d had reduced (P < 0.01) NK relative to those weaned at 21 or 28 d. Photoperiod also influenced pig BW and immune status. Generally, those pigs on the long-day photoperiod and weaned at 28 d were heavier (P < 0.001) than their counterparts weaned at 14 or 21 d. At 6 wk of age, NK was greater (P = 0.002) in pigs kept on a long day and weaned at 14 or 21 d than in pigs weaned at 28 d. Phagocytosis was less (P = 0.005) at 6 wk of age, but was greater at 8 wk, in piglets kept on the long day and weaned at 28 d than in long-day pigs weaned at 14 or 21 d. These results suggest that photoperiod differentially influences immune responses in piglets weaned at different ages and indicate an inverse relationship between growth and immune status. Here, weaning at 28 d and a long-day photoperiod was the treatment combination that was most physiologically beneficial to piglets, whereas a 14-d weaning and short-day photoperiod was least physiologically beneficial.

Animals↗
PubMed2006

Impacts of chronic stress and social status on various physiological and performance measures in pigs of different breeds.

Pigs typically experience various environmental stressors, which can negatively affect performance. Cortisol concentrations and various immune and performance measures are influenced by breed, but few data exist describing the impact of breed on stress responsiveness in pigs. The objective of this experiment was to determine if certain physiological responses to chronic stressors differed among 3 breeds and 2 commercial lines of pigs. The pigs were Landrace (n = 36), Meishan (n = 30), Yorkshire (n = 32), or 1 of 2 commercial lines (Line-A and Line-B; both n = 36). All pigs were weaned at 17 to 21 d and kept in a common nursery. At 49 d of age, pigs were assigned to 1 of 2 treatments: stress (heat, crowding, and mixing) or control (no stress treatment). Pigs were allocated to groups of 3 pigs per pen of the same sex. Control pigs were kept with their littermates. At the onset of the experiment, stressed pigs were mixed with 2 unfamiliar pigs once, and heat and crowding stressors were implemented simultaneously for 14 d. Pigs allocated to the stress treatment were video-recorded for 24 h following initiation of mixing to determine social status: dominant, intermediate, or submissive. Blood samples were taken at d 0 (baseline), 1, 7, and 14 to assess cortisol concentrations and immune measures. Breed and treatment affected cortisol, immune, and performance measures, but no significant breed x treatment interactions were found. In general, pigs subjected to the chronic stressor had lower (P < 0.001) BW and ADG (P < 0.001) than did control pigs. Plasma cortisol was lower (P < 0.001) among stressed pigs at d 7 and 14. Regardless of breed, lipopolysaccharide-induced proliferation (P < 0.01) and natural killer (NK; P < 0.005) cytotoxicity were greater in stressed pigs compared with controls. Furthermore, among stressed pigs, dominant pigs had a greater total white blood cell count (P < 0.005), NK (P < 0.05), and phagocytosis (P < 0.05) than the subordinate pigs. The results indicate that pig breed did not influence the physiological responses to the chronic concurrent stressors imposed for 14 d in this study, but social status did influence the immune responsiveness of these pigs to heat, crowding, and mixing.

Animals↗
PubMed2006

Photoperiod influences the immune status of multiparous pregnant sows and their piglets.

Manipulation of photoperiod may provide a noninvasive, easily implemented, effective method to improve immune status and enhance the efficiency of production. The objective of this study was to evaluate the impact of manipulation of photoperiod on endocrine and immune responses of pregnant sows and their offspring. At d 83 of gestation, sows were moved to gestation stalls and kept on a photoperiod of 12 h of light:12 h of dark until d 90, when sows were assigned to a long day (LD; 16 h of light/d) or a short day (SD; 8 h of light/d) treatment. During farrowing and lactation, one-half of the sows remained on their initial photoperiod (LD:LD or SD:SD), whereas one-half were switched to the opposite treatment (LD:SD or SD:LD). Blood samples were collected from sows at d 0, 7, 14, and 21 posttreatment, 24-h postfarrowing, and the end of lactation (approximately d 21 postfarrowing). Piglets were bled at 7 and 21 d of age for immune measures. Relative to sows on LD, sows on SD had greater concanavalin A- (P = 0.003) and lipopolysaccharide- (P = 0.02) induced proliferative responses at d 7 but reduced responses at d 14. Compared with SD, sows on LD had a greater (P < 0.05) percentage of neutrophils and fewer (P < 0.05) lymphocytes at d 7, resulting in a greater (P = 0.05) neutrophil:lymphocyte ratio. Neutrophil phagocytosis was greater at d 21 in sows kept on LD. Cortisol concentrations tended to be greatest (P = 0.10) in sows on SD:SD at 24-h postfarrowing and throughout lactation. At 7 d of age, piglets on LD:SD had greater (P = 0.001) total white blood cells (WBC) and plasma cortisol (P = 0.001) relative to those on the other photoperiod treatments. Plasma immunoglobulin G was less (P = 0.001) in piglets from sows kept on SD:LD compared with the other photoperiod treatments. Piglets from sows kept on LD:LD tended to have lower total WBC (P = 0.08) at 21 d of age. Piglets from sows kept on SD:SD had greater concanavalin A- (P < 0.001) and lipopolysaccharide-induced (P < or = 0.10) proliferation responses and cortisol (P = 0.05). Phagocytosis was greater (P < 0.003) in piglets from sows that were kept on LD:LD. Cortisol (P = 0.02), WBC (P = 0.003), and immunoglobulin G (P = 0.001) were all influenced by gestational photoperiod treatment. These data indicate that photoperiod influences the immune status and endocrine response of piglets from dams that have been kept on a defined photoperiod. We conclude that photoperiod effects on piglets may be programmed in utero and can last throughout lactation.

Animals↗
PubMed2005

Breed and age affect baseline immune traits, cortisol, and performance in growing pigs.

It was hypothesized in these studies that differences would exist in baseline immune and performance measures among different breeds of pigs, and that these differences would be affected by age of the pig. Baseline immune, plasma cortisol (CORT) concentrations, and performance measures were determined among Berkshire (n = 36), Duroc (n = 18), Meishan (n = 54), Landrace x Yorkshire (White X; n = 36), and Yorkshire (n = 36) pigs at 4, 8, and 12 wk of age. All piglets were weaned at 17 to 21 d of age and moved to a common nursery environment. Total white blood cell (WBC), leukocyte differential, plasma CORT, immunoglobulin G (IgG) concentrations, natural killer cytotoxicity, neutrophil phagocytosis (PHAGO), and chemotaxis (CHTX) were evaluated. At all ages, plasma CORT was greatest in Meishan pigs, and least in Yorkshires (P < 0.05). Plasma IgG increased with age for all breeds (age: P < 0.01; breed x age: P < 0.005), except that in Meishans, IgG decreased. Natural killer cytotoxicity was greatest (P < 0.05) among Meishan pigs. There were breed x age interactions for neutrophil PHAGO (P < 0.001) and CHTX (P < 0.001). Overall, Yorkshire pigs showed the greatest (P < 0.05) percentage of PHAGO but the least (P < 0.05) CHTX. White X pigs had the greatest (P < 0.05) CHTX response. Berkshire pigs had the greatest (P < 0.001) numbers of neutrophils. At 12 wk of age, Meishan pigs had the least BW gain (P < 0.001), and Durocs had the greatest G:F (P < 0.001). There were no significant sex differences for immune (P > or = 0.15), performance (P > or = 0.20), or CORT (P = 0.70) measures. Pig breed and age influenced both baseline immune measures and plasma CORT in growing pigs, suggesting that pig breed and age are important factors influencing the response to various stressors or infectious challenges.

Age Factors↗
PubMed2002

Cortisol responses to dehorning of calves given a 5-h local anaesthetic regimen plus phenylbutazone, ketoprofen, or adrenocorticotropic hormone prior to dehorning.

The purpose of this work was to assess whether the non-steroidal anti-inflammatory drugs (NSAIDs) phenylbutazone and ketoprofen, and an adrenocorticotropic hormone (ACTH) induced cortisol surge, reduce the cortisol response which occurs when the local anaesthetic wears off in calves following dehorning. There were four control groups and one dehorned group; also four groups were given local anaesthetic lasting 5h and were dehorned without or with phenylbutazone, ketoprofen or an ACTH injection, one group was injected with ACTH twice (at 0 and 6h) and another received ACTH and 6h later was dehorned. Blood samples were taken before and after dehorning and plasma cortisol concentrations were determined by radio-immunoassay. Dehorning increased the mean plasma cortisol concentrations [max 137 (11)nmoll(-1)] above control values [38 (5)nmoll(-1)] for about 7h, whereas local anaesthesia maintained concentrations at control values until about 5h after dehorning, and then they became elevated until about 10h. The maximum rise in mean concentration which occurred when the local anaesthetic wore off [128 (32)nmoll(-1)] was not affected when phenylbutazone was given before dehorning [141 (28)nmoll(-1)], but was reduced significantly when ketoprofen [65 (17)nmoll(-1)] or ACTH [61 (19)nmoll(-1)] were injected before or at the time of dehorning, respectively. Marked cortisol responses to ACTH injected at 0 and 6h were similar, but the early part of the cortisol response to dehorning 6h after an ACTH injection was reduced. It is suggested that the delayed cortisol response, which began 5h after dehorning, arose both from ketoprofen-sensitive and cortisol-sensitive sensory input as well as from other factors. Phenylbutazone did not affect the sensory input from the amputation wounds in the present calves.

Adrenocorticotropic Hormone↗
PubMed2002

Effect of local anaesthetic combined with wound cauterisation on the cortisol response to dehorning in calves.

OBJECTIVE: To reassess whether local anaesthesia before dehorning and wound cauterisation after dehorning eliminates the cortisol response to dehorning. METHODS: A control group was compared with three dehorned groups (dehorned alone, dehorned after local anaesthesia, dehorned after local anaesthesia then cautery of the amputation wounds). The local anaesthetic regimen used produced nerve blockade for about 5 h. Blood samples were taken before and after dehorning and plasma cortisol concentrations were determined. RESULTS: Dehorning caused a marked cortisol response lasting for about 7 h. Local anaesthetic reduced the plasma cortisol concentrations to control values for 5 h, after which they increased for a further 5 h. Subsequently in both groups, cortisol concentrations remained at control values until at least 24 h after treatment. Local anaesthetic combined with wound cautery virtually abolished the cortisol response until at least 24 h after dehorning. CONCLUSION: Combining local anaesthesia with cautery of the amputation wounds substantially reduced the cortisol response until at least 24 h after dehorning.

Anesthetics, Local↗
PubMed2000

Acute cortisol responses and wound healing in lambs after ring castration plus docking with or without application of a castration clamp to the scrotum.

OBJECTIVE: To test whether the cortisol response to ring castration plus docking is reduced by additional application of a castration clamp across the full width of the scrotum distal to the ring. DESIGN: A physiological study with controls. PROCEDURE: Lambs, 3 to 6 weeks of age, were castrated using a ring or ring plus castration clamp applied for 6 or 10 s and docked using a ring. Blood samples were taken before and regularly for about 4 h after treatment and analysed for plasma cortisol concentrations. The healing of the scrotal wounds was monitored for 6 weeks after castration. RESULTS: The plasma cortisol concentrations were lower only at 60 min after treatment in lambs castrated with a clamp placed on the scrotum for 10 s after ring castration and docking than in lambs castrated and docked by ring alone. Scrotal wounds healed more quickly after ring plus clamp than after ring only castration. CONCLUSIONS: The castration clamp had at most a marginal effect on the cortisol response to ring castration and docking of 3- to 6-week-old lambs, but it did seem to improve the rate of healing.

Animals↗
PubMed1999

Acute cortisol responses of lambs to ring castration and docking after the injection of lignocaine into the scrotal neck or testes at the time of ring application.

OBJECTIVE: To test whether injecting lignocaine into the scrotal neck 5 to 10 s before or into both testes immediately after ring castration and docking wound significantly reduce the plasma cortisol response to castration and docking. DESIGN: A physiological study with controls. PROCEDURE: Lambs were given one of six treatments: control handling, injection of lignocaine into scrotal neck, injection of lignocaine into both testes, ring castration and docking, ring castration and docking after lignocaine was injected into the scrotal neck, and ring castration and docking before lignocaine was injected into both testes. Blood samples were taken before and regularly after treatment and analysed for plasma cortisol concentrations. RESULTS: The plasma cortisol concentrations of lambs castrated and docked after lignocaine had been injected into the scrotal neck were significantly lower between 20 and 60 min after treatment than in lambs castrated and docked without local anaesthesia. Injecting lignocaine into the testes after ring application did not significantly reduce the cortisol response to ring castration and docking. CONCLUSIONS: Lignocaine injected into the scrotal neck 5 to 10 s before ring castration will reduce the cortisol response and by inference the pain associated with ring castration.

Anesthesia, Local↗
PubMed1983

Leucocyte adherence inhibition and carcinoembryonic antigen in combination for diagnosis of colorectal cancer.

A combination of leucocyte adherence (LAI) and carcinoembryonic antigen (CEA) diagnosed colorectal carcinoma with 91% sensitivity and 68% specificity. Relative operating characteristic (ROC) analysis was used to calculate the cutoff points for optimum detectability in a group of 159 patients with bowel symptoms who were investigated by endoscopy and radiology. Combining LAI and CEA would be likely to reduce the chance of missed diagnosis of colorectal carcinoma when x-ray and colonoscopic findings are equivocal.

Adenoma↗