Search

Stone chewing is a common behaviour in outdoor sows, but its effects on their teeth and stomachs have not been investigated. Tooth wear and damage was assessed by examining the heads of 58 sows culled from outdoor units and 23 culled from indoor units. Tooth damage was found in 28 per cent of outdoor and 30 per cent of the indoor sows, and tooth wear affected 88 per cent of the outdoor and 91 per cent of the indoor sows. The outdoor sows were more prone to wear on the lower molars and premolars, a pattern of wear associated with stone chewing. The stomachs of 152 outdoor sows and 47 indoor sows were examined. Stones were found in 59 of the outdoor sows but in none of those kept indoors. There was no evidence that the presence of stones damaged the stomach, or that stone chewing affected the health of the sows. The teeth of the outdoor sows were worn, but probably not sufficiently to affect their ability to eat during their relatively short productive lives.

In an abattoir survey the stomachs of 1242 pigs from 15 farms were examined. Ulceration of the pars oesophagea was present in 22.95 per cent with a range from 4.7 to 57.4 per cent. The ulcers were graded mild in 9.5 per cent and severe in 13.4 per cent of the stomachs. Bile staining and hyperkeratinisation of the pars were significantly more common in stomachs with ulcers than in those without (P < 0.001), although the difference between the hyperkeratinisation in cases with severe ulcers and cases without ulcers was not significant. The daily liveweight gains of 208 males and 150 females from two units with a high prevalence of ulcers were calculated from their weaning weights at about five weeks of age and their slaughter weights at around 90 kg. At the abattoir their stomachs were examined for the presence of ulcers of the pars. The daily liveweight gain of the males was significantly greater than that of the females (P < 0.001), but the presence of mild or severe ulcers had no influence on the rate of gain of the pigs from either unit. The prevalence of ulcers in the males and females was 57.2 and 49.3 per cent, respectively, but the difference was not significant.

Pigs from four farms (two producing 'easy' and two 'difficult to handle' pigs) were slaughtered at two abattoirs, each with two slaughter handling systems, so that 25 pigs of each behavioural type were slaughtered by all four handling systems on each day; there were 16 replicates (3200 pigs) in total. The pigs at abattoir X were electrically stunned, either in a floor pen holding five pigs or in a race-restrainer. At abattoir Y the pigs were stunned either in a floor pen holding five pigs or in a dip-lift carbon dioxide stunner. The following measurements were made: hot carcase weight and backfat thickness at P2, degree of rigor mortis 35 minutes post mortem, skin blemish, pH and muscle reflectance in the m longissimus dorsi at 60 minutes and 18 hours post mortem, and pH and muscle reflectance in the m adductor at 18 hours post mortem. At abattoir X, the pigs slaughtered in the race-restrainer had heavier carcases (74.0 kg vs 73.0 kg, P < 0.05), developed rigor mortis more rapidly (8.1 mm vs 7.3 mm, P < 0.01), had more skin blemish (2.8 vs 2.7, P < 0.01), paler m longissimus dorsi muscles after one hour (15.7 vs 13.9, P < 0.01) and 18 hours (27.8 vs 26.6, P < 0.05), and paler m adductor muscles (24.5 vs 22.7, P < 0.001) after 18 hours. At abattoir Y, the pigs handled through the floor pen system had more skin blemish (2.7 vs 2.6, P < 0.05) and a tendency to develop rigor mortis more quickly (6.11 vs 5.32, P = 0.089).(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of feeding the beta-adrenergic agonist salbutamol to pigs at levels between 0.5 and 5.0 mg/kg feed for different periods were studied in six experiments. The feet and ability to walk of pigs weighing 30 to 100 kg were examined at intervals. False sand-crack, white-line and heel erosion lesions were classified as mild or severe, and corns and wall haemorrhages were also recorded. At each examination the pig was given a grade for the overall severity of its foot lesions. Salbutamol fed at 1.0 to 5.0 mg/kg feed, for as little as 21 to 28 days, increased the frequency (P < 0.05 to 0.001) and often the severity (P < 0.05) of the foot lesions, the higher doses tending to produce more severe lesions, and the overall foot grades deteriorated (P < 0.001). The effects on both sexes were similar. No changes were observed when 0.5 mg/kg was fed for 56 days. Despite the severity of many of the foot lesions, the pigs became lame in only one experiment. Electron microscopy indicated that salbutamol was interfering with horn production, but light microscopy revealed no changes in skin sections. These findings suggested that salbutamol was not directly affecting the function of keratinocytes. Supplementing the diet of the pigs with biotin and methionine did not delay, or prevent, the effects of salbutamol.

Pigs from four farms were slaughtered at two abattoirs, each with two slaughter handling systems. Pigs at abattoir X were electrically stunned, either in a floor pen holding five pigs or in a race-restrainer. At abattoir Y pigs were stunned either in a floor pen holding five pigs or in a dip-lift carbon dioxide stunner. At exsanguination, 96 blood samples (24/farm) were collected from pigs slaughtered through each slaughter handling system (384 samples in total). Serum samples were analysed for cortisol, creatine phosphokinase (CPK) lactate dehydrogenase (LDH) and LDH-isoenzymes. There were no significant differences between the systems at abattoir X. At abattoir Y, pigs slaughtered through the floor pen system had higher levels of LDH-5 (39.84 +/- 1.39 per cent of total LDH vs 34.76 +/- 1.21 per cent, P < 0.05) indicating greater skeletal muscle damage in the floor pen. Pigs at abattoir Y had higher mean serum levels of CPK than pigs at abattoir X (3.63 log10 U/litre vs 3.41 log10 U/litre, 0.03 sed, P < 0.001), higher total LDH activities (1269.5 U/litre vs 922.8 U/litre, P < 0.001) and higher cortisol concentrations (1.70 log10 ng/ml vs 1.51 log10 ng/ml, P < 0.001). These differences suggested that the levels of physical and psychological stress were higher at abattoir Y.

On eight farms alternate sows and gilts within three weeks of their expected farrowing date were injected intramuscularly in the neck with 8 ml of an iron (gleptoferron) preparation containing 200 mg iron/ml, or kept as uninjected controls. Data from 513 iron-injected and 488 control animals were used in the analysis of results. Small, but not statistically significant, improvements were observed in the numbers of piglets born alive and dead/litter, the birth weights and weaning weights at three weeks, the numbers of piglets fostered on and off/litter, piglet mortality, the number weaned/litter and the weaning to service interval. The condition scores of the iron-injected sows were marginally below those of the controls at weaning, but their condition scores at farrowing had also been slightly below those of the controls. A summation of these trends would suggest an overall benefit of approximately 0.45 pigs/sow/year in favour of the iron-injected sows.

A herd of 116 sows was divided into two groups. Animals in one group had their food supplemented with 1160 micrograms/day of biotin in pregnancy and 2320 micrograms/day in lactation, over a 12-month period. The other group served as a control. Those receiving biotin farrowed significantly more live pigs in parities 2 and 4 than in the control animals; the increase in parity 3 only just failed to reach significance. There was no consistent effect on the weaning to service internal although a significant difference (P = 0.05) was seen with the third litters.

A herd of 116 sows with a high frequency of foot lesions and lameness was divided into two groups, A and B. Group B was supplemented with 1160 microgram per day of biotin in pregnancy and 2320 microgram per day in lactation, over a 12-month period. No improvement occurred in the condition of the feet or skin. Gilts introduced as replacements to the herd were allocated alternately to the groups. Those receiving biotin (group B) showed significantly fewer lesions of heel erosion, white-line, heel bruising and "corn", and the severity and number of lesions of the lateral hind claws were also significantly improved.

The growth and wear rate of claw horn was measured in 42 commercial hybrid pigs. Half received a ration supplemented with 1 mg d-biotin/kg food daily, while the others acted as controls. The start weights of three replicates of 10 pigs averaged 25 kg and their mean finishing weight was 85 kg. Twelve pigs averaged 18 kg at the start and 118 kg at the end of the experiment. No differences in horn growth and wear rates were found between the biotin-supplemented pigs and the controls, or between the front and hind claws, although horn growth and wear both decreased with age. Claw horn grew at an average of 10 mm/28 days in the pigs taken from 25 to 85 kg bodyweight and at 11 mm/28 days in the pigs taken from 18 to 118 kg. The mean rate of wear of claw horn was 6 mm/28 days.

The snouts of 2701 pork, bacon and heavy pigs killed at five abattoirs in England and Scotland during March to July 1974 were examined for evidence of atrophic rhinitis. Lesions were graded 1 to 5 according to severity. Suspicious lesions were present in 75-7 per cent of the sample. There was obvious atrophy of the turbinates in 44-7 per cent (grade 2 to 5) and severe atrophy in 17-5 per cent (grades 3 to 5). Foreign bodies were found in or between the posterior cheek teeth of 5-3 per cent of the sample. There was frequently an associated gingivitis. Other lesions seen included black discolouration of the teeth, severe tooth wear and osteoarthrosis of the temporomandibular joint. It was concluded that the incidence of atrophic rhinitis could have increased markedly since the last survey of the United Kingdom was undertaken in 1956/57 and some form of disease-monitoring service was urgently needed.

A postal survey was carried out by the Pig Veterinary Society to establish the opinions of its members on priorities for pig research: 153 members, 64 per cent of the total--returned analysable questionnaires. The survey shows that problems of highest priority for members are atrophic rhinitis, non-infectious infertility, neonatal enteritis, economics of disease, preventive medicine programmes and swine dysentery. The membership was classified by the nature of their work into five groups and the six subjects listed above cover the top three priorities of all groups. A classification of the papers listed in the Index of Current Research on Pigs XXII 1976 suggests that some of the six subjects are under researched.

The clinical responses of sheep dosed orally over seven to 14 weeks with the dried mycelium of a soil-borne mould containing the tremorgenic mycotoxin penitrem A are described. An initial tremoring response was gradually overshadowed by an incoordination syndrome similar to that seen in ryegrass staggers. In spite of protracted staggers symptomatology, correlated with in vitro changes in the release of neurotransmitter amino acids from corpus striatum nerve ending preparations, no histopathology was evident in the wide range of neural and other tissue studied. The biochemical nature of this reversible mycotoxicosis is discussed.

Supplementary biotin (1 mg d-biotin/kg feed) increased the compressive strength of the mid-abaxial sidewall region of pig's hoof from 9.3 (+/- 0.5) X 10(6) N/m2 to 12.0 (+/- 0.5) X 10(6) N/m2 (P less than 0.05). It also increased the hardness of this region, measured on the Shore A and D hardness scales (P less than 0.05). The leading edge of the hoof wall was significantly stronger than the sidewall (P less than 0.001) with a compressive strength of 14.5 (+/- 0.7) X 10(6) N/m2. This site showed no significant improvement in compressive strength or hardness in response to biotin. Biotin also produced a significant decrease in the hardness of the heel bulb on the Shore A scale (P less than 0.05). There would therefore appear to be a rational biomechanical basis for the finding by others that biotin reduces lameness. The Shore A and D hardness testers are sensitive to the improvement produced by biotin and may be useful as small, hand-held hoof testing devices for use in field conditions by the practising veterinarian.

Half the progeny in a 200-sow herd (2045 pigs) was given feed medicated with 500 g/tonne of a 1:5 trimethoprim/sulphadiazine mixture from three to nine weeks of age. The other half (1989) acted as controls. The trial lasted 12 months. No difference was observed between the two groups in the incidence of streptococcal meningitis and the morbidity and mortality from all disease causes during the growing/fattening periods did not differ significantly. The main diseases encountered were pneumonia (7.24 per cent), streptococcal meningitis (5.12 per cent), leg and foot disorders (3.34 per cent) and the after-effects of vices (1.86 per cent). The resistance of faecal coliforms to trimethoprim was studied during the six-week period of trimethoprim/sulphadiazine feeding. Faecal coliforms in both medicated and non-medicated groups developed almost 100 per cent resistance. However, resistance developed more slowly in the untreated pigs. The medicated pigs showed a small overall improvement in feed conversion rate up to 18 weeks of age mainly because of a marked improvement between three and six weeks.