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PubMed2004

Impact of sawdust and wood shavings in bedding on pig tuberculous lesions in lymph nodes, and IS1245 RFLP analysis of Mycobacterium avium subsp. hominissuis of serotypes 6 and 8 isolated from pigs and environment.

Among 25,027 slaughter pigs raised in two farms, tuberculous lesions were detected in the lymph nodes of 898 (3.6%) of them. Tuberculous lesions were most commonly found in the mesenteric (601; 2.4%) and head (451; 1.8%) lymph nodes. Mycobacteria were isolated from 49 of 120 randomly selected mesenteric, head and bronchial lymph nodes with diagnosed tuberculosis originating from both farms. Forty six Mycobacterium avium subsp. hominissuis, one M. chelonae and two M. fortuitum isolates were found in the lymph nodes of pigs. No statistically significant difference was detected between farms A and B for isolation rates of mycobacteria from the lymph nodes of pigs and their species composition. To investigate the source of the pigs' infections, culture examinations of 117 samples from the external environment were performed. Mycobacteria were isolated from 25 samples from the external environment (21.4%). Mycobacterial isolates were also detected in eleven (91.7%) and two (16.7%) of 12 used sawdust and 12 of non-used (fresh) sawdust samples, respectively. None of 12 wood shavings was culture-positive. Twelve of 13 sawdust isolates were classified as M. a. hominissuis of serotypes 6 and 8 and genotype IS901- and IS1245+; the remaining isolate was classified as species M. fortuitum. Other conditionally pathogenic mycobacteria were only isolated from 12 of the remaining 81 samples from the external environment (excluding bedding). A total of eight isolates (two pig and six sawdust samples originating from farms A and B) were examined by IS1245 restriction fragment length polymorphism (IS1245 RFLP) analysis. These isolates produced five distinct IS1245 RFLP types with more than 20 bands. Based on identical IS1245 RFLP types of one pig isolate and two isolates of used sawdust from farm A, we have concluded that contaminated sawdust was the source of mycobacterial infection for pigs in our study.

Animals↗

PubMed1997

Myelosuppression in the pig (Sus scrofa): uteroferrin reduces the myelosuppressive effects of 5-fluorouracil in young pigs.

The present study investigated the ability of uteroferrin to modulate the myelosuppressive effects of 5-fluorouracil (5-FU) in young pigs (Sus scrofa). Pigs (28-35 days of age; n = 6 per treatment) were infused with equal amounts of 5-FU on days 0 and 1 of the experimental period (37.5 mg/kg cumulative dose). Uteroferrin (100 micrograms/kg in 0.9% NaCl) or control (equivalent volume of 0.9% NaCl) was administered to pigs as intramuscular injections twice daily (08:00 and 20:00 hr) on days 1 through 21. Peripheral blood cell number, composition and progenitor cells were determined over 28 days. Treatment of pigs with 5-FU resulted in a rapid dose-dependent (P < 0.05) leukocytopenia. Concurrent treatment of pigs with uteroferrin reduced (P < 0.05) the rate of 5-FU-induced leukocytopenia (44 vs 77 +/- 7% decline from baseline on day 3) and enhanced (P < 0.05), the recovery from 5-FU on days 10 and 12 postinfusion. The positive effect of uteroferrin on leukocytes resulted primarily from a protection and/or enhanced recovery of neutrophils and monocytes. In addition, uteroferrin attenuated (P < 0.05) the suppression of red blood cell numbers after 5-FU administration (6.9 vs 6.1 +/- 0.2 x 10(6) cells/microliter on day 3), an affect reflected in increased hematocrit and hemoglobin concentrations. The effects of uteroferrin appeared to result from enhancement of the proliferation and/or differentiation of primitive pluripotent stem cells resistant to 5-FU, as concurrent treatment of pigs with uteroferrin resulted in a protection and/or enhanced recovery (P < 0.05) of CFU-GEMM, CFU-GM and BFU-E progenitor cells in the peripheral blood. These results are the first to demonstrate that uteroferrin can reduce the myelosuppressive effects of 5-FU in the pig and suggest that uteroferrin has hematopoietic growth factor activity in vivo.

Acid Phosphatase↗

PubMed1971

The comparative susceptibility of hysterectomy-produced, colostrum-deprived pigs and naturally born, enzootic-pneumonia-free pigs to enzootic pneumonia.

Hysterectomy-produced, colostrum-deprived (HPCD) pigs and naturally born, enzootic-pneumonia-free (EPF) pigs were compared with respect to their susceptibility to two strains of enzootic pneumonia induced by intranasal inoculation of suspensions of ground pneumonic tissue. All but one of the HPCD pigs developed enzootic pneumonia, whereas the EPF pigs commonly failed to develop the disease; secondly, the pneumonic lesions were more extensive in the HPCD pigs.When the dose of inoculum was increased in EPF pigs, the resulting pneumonic areas were larger.In a small, in-contact experiment the disease was also more readily transmitted to HPCD pigs than to EPF pigs.

Animals↗

PubMed2001

Pig paramyxovirus of the blue eye disease binding to a 116 kDa glycoprotein expressed in pig neuronal membranes.

UNLABELLED: Pig paramyxovirus of the blue eye disease (PPBED) is a novel member of the paramyxoviridac family which infects pigs. In neonatal pigs it causes neurological damage, whereas in adult pigs it affects the reproductive function. As PPBED damages the new-born pig central nervous system (CNS), it is important to study whether PPBED binds to the membrane proteins of all brain tissue, or selectively binds to neuronal tissue of the brain stem, olfactory bulb, hippocampus, cerebellum, frontal, temporal and parietal brain cortex. It is also important to establish whether it also infects neurones obtained from new-born, 60-day-old and adult pigs, and the role of carbohydrate residues in virus binding. The effect on virus binding of polyclonal antibodies against viral envelope proteins was also studied. Binding studies were performed using dot blot and virus overlay protein binding assays. PPBED was able to bind to membrane proteins from all brain regions, particularly to a protein band of approximately 116 kDa. Neuraminidase treatment of neuronal membrane proteins decreased virus binding; subsequent treatments with beta-galactosidase and manosidase did not increase virus binding inhibition. N-glycosidase F and trypsin also decreased virus binding, but not the O-glycanase. Antibodies against viral haemagglutinin-neuraminidase blocked virus binding more efficiently than antibodies against viral fusion protein. IN CONCLUSION: (1) PPBFD is able to bind to pig neurones of all brain regions studied and at all ages analysed; (2) a 116 kDa membrane protein containing sialic acid residues with an N-linked oligosaccharide chain was specifically recognized; (3) PPBED haemagglutinin-neuraminidase protein seems to play a central role in neural receptor recognition.

Animals↗

PubMed1996

PIG-A and PIG-H, which participate in glycosylphosphatidylinositol anchor biosynthesis, form a protein complex in the endoplasmic reticulum.

Many eukaryotic cell surface proteins are bound to the membrane via a glycosylphosphatidylinositol (GPI) anchor. Assembly of the GPI anchor precursor is a sequential addition of components to phosphatidylinositol (PI) in the endoplasmic reticulum (ER). The first step is the transfer of N-acetylglucosamine (GlcNAc) to PI from UDP-GlcNAc to generate GlcNAc-PI. This simple step, however, is regulated by at least three genes because in both mammals and yeasts, there are three mutants of different complementation classes. To clarify this complexity, we analyzed the products of two cloned human genes, PIG-A and PIG-H. Here we demonstrate 1) that PIG-A is an ER transmembrane protein with a large cytoplasmic domain that has homology to a bacterial GlcNAc transferase and a small lumenal domain; 2) that PIG-H is a cytoplasmically oriented, ER-associated protein; and 3) that they form a protein complex. We also show that part of the small lumenal domain of PIG-A plays an essential functional role in targeting itself to the rough ER. Taken together with the cytoplasmic orientation of GlcNAc-PI, these results indicated that PIG-A and PIG-H are subunits of the GPI GlcNAc transferase that transfers GlcNAc to PI on the cytoplasmic side of the ER.

Animals↗

PubMed1978

Gastric secretion in suckling pigs and early-weaned pigs given a dry cow's-mild formula ad lib.

1. Twelve gastric-cannulated litter-mate pigs were used to study secretion and proteolytic activity in the stomach of suckling and early-weaned pigs in relation to age and food intake. 2. Results demonstrate that from the first observation at day 8, piglets were able to secrete acid. pH and acid concentration did not change during the first 4 weeks of life. 3. Proteolytic activity was low during the first 2--3 weeks of life and rapidly increased thereafter. 4. Two phenomena differentiated suckling pigs from pigs given dry cow's milk: (1) a low buffering capacity the gastric contents, beginning 1 hr after feeding the dry cow's-milk formula, results in a low total acid concentration in the weaned pigs and (2) the increase in proteolytic activity in relation to the age is much more pronounced in the artificially-reared pigs. 5. These two phenomena are discussed and related to the formation of a hard casein clot in the stomach of the cow's-milk-fed pigs, which has a long retention time and stimulates gastrin release.

Animals↗

PubMed1993

Phosphorus studies in pigs. 1. Available phosphorus requirements of grower/finisher pigs.

Two experiments were conducted to determine the available P requirements of grower and grower/finisher pigs and to define the conditions for conducting a growth assay for P availability. In the first experiment, diets with four levels of calculated available P (1-4 g/kg) and four Ca:available P ratios (1.7-2.9) were used to determine the available P requirements of grower pigs. The diets were formulated by substituting the required amounts of limestone and sodium tripolyphosphate for sugar in a soya-bean meal and sugar-based diet. In addition to measuring growth responses, a range of bones were examined to determine the most suitable criteria for assessing the response to available P. There was a small quadratic response of feed intake and growth rate of the pigs to level of available P, with maximum responses occurring to approximately 3 g available P/kg (P < 0.05). There were linear depressing effects of increasing Ca:available P ratios on carcass gain and feed conversion ratio (P < 0.01) but most of these effects occurred when the ratio exceeded 2.5:1. All bone variables examined increased linearly (P < 0.05) or curvilinearly (P < 0.01) with increasing available P concentration. In general, these variables were not affected by the Ca:available P ratio. The results of the growth responses and bone development indicate that the grower pig requires approximately 3 g available P/kg. However, for availability assays, where linearity of response is needed, the dietary concentration of available P should be a maximum of approximately 2 g/kg. In the second experiment four levels of calculated available P (1-4 g/kg) with a Ca:available P ratio of 2.5:1 were used to determine the available P requirements of grower/finisher pigs from 20 to 90 kg live weight. At 50 kg live weight the dietary available P concentration for half the pigs fed at 2, 3 and 4 g available P/kg was reduced to 1, 2 and 3 g/kg respectively. The pigs were fed ad lib, and growth performance, bone characteristics, P retention and ash concentration in the empty body were taken as response criteria to assess P adequacy. Among the variables tested, the ash concentration in the radius/ulna bone and P and ash concentrations in the empty body appeared to be more responsive than other variables to the changes in dietary P levels.(ABSTRACT TRUNCATED AT 400 WORDS)

Animal Nutritional Physiological Phenomena↗

PubMed1995

The effect of heat on amino acids for growing pigs. 4. Nitrogen balance and urine, serum and plasma composition of growing pigs fed on raw or heat-treated field peas (Pisum sativum).

Experiments were conducted to determine the effect of heating field peas (Pisum sativum) on the N balance and urine, serum and plasma composition of growing pigs. In the first experiment, four diets containing raw field peas (cv. Wirrega) or field peas heated to 150 degrees (cv. Wirrega), 165 degrees (cv. Wirrega) or 150 degrees (cv. Dundale) for 15 min respectively were formulated to contain 1.15 g ileal digestible N/MJ digestible energy (DE) and 0.36 g ileal digestible lysine/MJ DE in a sugar-based diet. Digestibility estimates were based on those for the Dundale cultivar of field peas used in previous experiments. Total urine and faeces collection from eight pigs was conducted over two 7 d collection periods with a 7 d diet change-over period. Serial blood sampling from the external jugular vein was conducted on the final day of each collection period. There was no significant difference (P > 0.05) in the N balance or apparent biological value of the field-pea treatments. Pigs fed on diets containing peas heated to 150 degrees (cv. Wirrega) or 165 degrees (cv. Wirrega) had a significantly lower (P < 0.01) daily output of urea and uric acid in the urine, and depressed serum protein and serum urea concentrations. Plasma lysine concentration and daily urine lysine output were not significantly different (P > 0.05) in pigs fed on heated peas. Protein excretion in the urine of pigs fed on diets containing peas heated to 165 degrees increased 3-7 times (depending on estimation technique) the level observed in pigs fed on diets containing raw peas. A second experiment was conducted to determine the apparent ileal digestibility of N and amino acids in cv. Wirrega field peas. This study revealed that N digestibility (0.44) and lysine digestibility (0.35) in peas heated to 165 degrees were significantly lower than the cv. Dundale estimates (0.57 and 0.62 respectively) used in diet formulations. The depressed serum and urine variables in pigs fed on heated peas were attributed to overestimation of digestibility. The results exemplify the fact that it is not possible to draw general conclusions as to the effects of heat on any particular protein concentrate. Variability in N balance experiments and problems associated with urine analysis are suggested as likely reasons for the current study not reflecting poor utilization of ileal digestible lysine from heat-treated field peas.(ABSTRACT TRUNCATED AT 400 WORDS)

Amino Acids↗

PubMed2000

A polymerase chain reaction-based protocol for the detection of transmission of pig endogenous retroviruses in pig to human xenotransplantation.

BACKGROUND: Xenotransplantation of pig organs and tissues to humans bears the risk of infection of immunosuppressed recipients by porcine endogenous retrovirus (PERV) released from the transplanted tissue. However, when diagnosing potential PERV transmission, it is essential to exclude microchimerism, i.e., persisting pig cells in analyzed bioptic material of xenotransplanted patients, which give rise to false positive PERV signals. Polymerase chain reaction (PCR) is so far the only suitable method to diagnose a cross-species transfer of PERV, but the exclusion of microchimerism might be a serious problem because most of the presently employed primer pairs detect PERV sequences with higher sensitivity than primers used for the detection of contaminating pig sequences. METHODS: We designed and evaluated a novel and improved primer set for detection of pig sequences as well as complementing positive control primers on the basis of mitochondrial cytochrome B, an approved marker for phylogenetic studies. We further established primer pairs derived from the long terminal repeat/leader region of PERV isolated from a Duroc German Landrace cross-bred pig and tested their sensitivity in comparison with known PERV- and pig-specific PCR markers. RESULTS: In standard PCR assays, the new cytochrome B-derived primers are at least 10 times more sensitive than the presently used PERV retroviral polymerase gene and mammalian beta-actin primers. When tested in a tissue culture infection model, PERV transmission to human 293 cells can be unambiguously demonstrated, even in the presence of up to 10% pig cells. One of the primer combinations derived from the PERV DuxDL3791 long terminal repeat/leader region amplifies with even lower sensitivity than primers detecting porcine beta-globin, thus permitting the exclusion of microchimerism also via chromosomal loci. CONCLUSIONS: The availability of the new PCR markers allows the proposal of a rigorous setup for the routine detection of PERV transmission after xenotransplantation.

Actins↗

PubMed1994

Reduced virulence of Serpulina hyodysenteriae hemolysin-negative mutants in pigs and their potential to protect pigs against challenge with a virulent strain.

The role of the Serpulina hyodysenteriae hemolysin encoded by the tlyA gene in the pathogenesis of swine dysentery (SD) was studied. tlyA mutants of two S. hyodysenteriae strains (B204 and C5) were tested for virulence in pigs. None of the animals developed SD. However, after infection with wild-type strain B204 or C5, the incidence of SD was 100 or 60%, respectively. Thus, the tlyA-encoded hemolysin of S. hyodysenteriae is an important virulence factor in SD. The potential of these mutants to protect pigs against challenge with a virulent S. hyodysenteriae strain was also studied. After challenge with wild-type strain B204, 50% of pigs previously inoculated with the B204 tlyA mutant were protected, whereas all control pigs contracted SD. None of the pigs previously inoculated with the C5 tlyA mutant developed SD upon challenge with wild-type strain B204, whereas 40% of the control pigs developed SD in this experiment. Thus, previous colonization with S. hyodysenteriae tlyA mutants in pigs provides partial protection against challenge with a virulent S. hyodysenteriae strain.

Animals↗

PubMed2004

Instability of the restriction fragment length polymorphism pattern of open reading frame 5 of porcine reproductive and respiratory syndrome virus during sequential pig-to-pig passages.

Restriction fragment length polymorphism (RFLP) analysis is one of the tools commonly used to study the molecular epidemiology of porcine reproductive and respiratory syndrome viruses (PRRSVs). As PRRSVs are genetically variable, the stability of the RFLP pattern of a PRRSV during in vivo replication was evaluated by carrying out 13 sequential pig-to-pig passages (P1 to P13) of PRRSV ATCC VR-2332 in three independent pig lines for a total of 727 days. During P1 the pigs were inoculated with a homogeneous inoculum (CC-01) prepared through a series of plaque purifications, and during P2 to P13 the pigs were inoculated with a tissue filtrate from the corresponding pig in the previous passage. Fifteen viral plaque clones were directly isolated from CC-01 and the day 7 serum of each pig of each passage, open reading frame 5 of the clones was sequenced, and the clones were compared to CC-01 to assess the mutation rates and RFLP patterns (obtained by digestion with MluI, HincII, and SacII) over time. Among the 495 viral clones recovered during the passages, 398 clones, including CC-01, had pattern 2-5-2 (MluI-HincII-SacII); however, the remaining 97 viral clones showed different patterns (2-6-2 [P2], 1-5-2 [P3], 2-5-4 [P7], and 2-1-2 [P10]). Importantly, the MluI site that was reported to be present in only one of the PRRS modified live virus vaccine strains (Ingelvac) and its parental strain (ATCC VR-2332) can disappear during in vivo replication. Furthermore, sequence homology between CC-01 and clones with pattern 2-5-2 or clones with other patterns differed by 0.05 to 1.58% and 0.5 to 1.45%, respectively, suggesting that RFLP analysis cannot accurately predict genetic relatedness between PRRSVs. Collectively, precaution should be taken when the molecular epidemiology of PRRSVs is evaluated by RFLP analysis.

Animals↗

PubMed1994

An inherited lower motor neuron disease of pigs: clinical signs in two litters and pathology of an affected pig.

A chronic progressive neurodegeneration, called hereditary porcine neuronal system degeneration (HPNSD), was recognized in a swine herd in Devon, England. Adult pigs that were presumed carriers of the dominantly inherited trait for HPNSD were transferred from England, where a breeding colony was maintained for 9 years, to the Wyoming State Veterinary Laboratory (WSVL) for study. Two litters of affected piglets were born to 2 carrier sows at the WSVL. Clinical signs of muscular tremors, paresis, or ataxia developed at 12-59 days of age in 4 of 6 liveborn pigs. Three other pigs were stillborn. In the 4 affected liveborn pigs, clinical signs progressed and included symmetrical (3 pigs) or asymmetrical (1 pig) posterior paresis, bilateral knuckling of metatarsal-phalangeal or carpal joints, poor exercise tolerance, and in 1 pig, marked hind limb hypermetria. A 34-kg gilt exhibiting clinical signs of muscular tremors and posterior paresis and clinical signs for 22 days was euthanized and examined postmortem at 83 days of age. Apart from decubitus ulcers, gross lesions were absent. Microscopically, perikaryal vacuolation and osmiophilic lipid droplets were observed in atrophic alpha motor neurons in the spinal cord. There was axonal (Wallerian) degeneration in sulcomarginal and dorsal spinocerebellar tracts. Axonal degeneration also involved ventral but not dorsal spinal nerve roots, and was present in eight peripheral nerves sampled for histopathology. Changes in skeletal muscles were consistent with denervation atrophy and were most pronounced in M. tibialis cranialis of the 6 muscles sampled. Immunohistochemical staining of spinal cord for phosphorylated and nonphosphorylated neurofilaments did not reveal abnormal patterns, unlike some well-characterized inherited motor neuron diseases in other species.

Animals↗

PubMed2005

Pigs in sequence space: a 0.66X coverage pig genome survey based on shotgun sequencing.

BACKGROUND: Comparative whole genome analysis of Mammalia can benefit from the addition of more species. The pig is an obvious choice due to its economic and medical importance as well as its evolutionary position in the artiodactyls. RESULTS: We have generated approximately 3.84 million shotgun sequences (0.66X coverage) from the pig genome. The data are hereby released (NCBI Trace repository with center name "SDJVP", and project name "Sino-Danish Pig Genome Project") together with an initial evolutionary analysis. The non-repetitive fraction of the sequences was aligned to the UCSC human-mouse alignment and the resulting three-species alignments were annotated using the human genome annotation. Ultra-conserved elements and miRNAs were identified. The results show that for each of these types of orthologous data, pig is much closer to human than mouse is. Purifying selection has been more efficient in pig compared to human, but not as efficient as in mouse, and pig seems to have an isochore structure most similar to the structure in human. CONCLUSION: The addition of the pig to the set of species sequenced at low coverage adds to the understanding of selective pressures that have acted on the human genome by bisecting the evolutionary branch between human and mouse with the mouse branch being approximately 3 times as long as the human branch. Additionally, the joint alignment of the shot-gun sequences to the human-mouse alignment offers the investigator a rapid way to defining specific regions for analysis and resequencing.

Animals↗

PubMed2006

Increases in pig major acute-phase protein in wasting pigs brought to the abattoir.

Plasma proteins of wasting pigs were quantitatively and qualitatively compared with those of normal fattening pigs. Higher expression of a 120 kDa protein was observed in the plasma of wasting pigs by SDS-PAGE. This protein was identified as pig major acute-phase protein (Pig-MAP) by proteomic analysis using two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The plasma concentration of Pig-MAP in wasting pigs was 7-fold higher than that of normal ones.

Abattoirs↗

PubMed2002

Variation in mitochondrial DNA of Vietnamese pigs: relationships with Asian domestic pigs and Ryukyu wild boars.

Mitochondrial DNA (mtDNA) sequences (574 bp) of 30 Vietnamese pigs (large and small) were examined and compared with those of 61 haplotypes from wild boars and domestic pigs from various locations in Asia. The large Vietnamese pigs had genetic links to Ryukyu wild boars in southern Japan. The small Vietnamese pigs were closely related to other East Asian domestic pigs. These results indicate that Vietnamese pigs are genetically diverse and may be descendents of wild and domestic pigs from other regions of Asia.

Animals↗

PubMed2001

Progress of farrowing and early postnatal pig behavior in relation to genetic merit for pig survival.

The objective of this study was to investigate whether pigs with different genetic merit for survival differed in birth weight, progress of farrowing, early postnatal behavior, or rectal temperature within 24 h after birth. On a nucleus farm in Rio Verde, Brazil, information was collected on 280 pigs, originating from 25 litters with known estimated breeding values for pig survival (EBVps). Litters were selected in such a way that a continuous range of EBVps with a maximum genetic contrast was achieved. Birth weight was recorded for all pigs. Indicators for progress of farrowing were birth intervals and duration of farrowing. Behavioral indicators of pig vitality were time until first upright standing (FUS), time until first udder contact (FUC), time until first teat in mouth (FTM), and time until first colostrum uptake (FCU). Rectal temperature was measured within 24 h after birth. Farrowing survival and early postnatal survival (within 3 d after farrowing) were registered. Farrowing survival and early postnatal survival both increased with increasing EBVps (farrowing survival: P = 0.007; early postnatal survival: P = 0.027). Birth weight decreased with increasing EBVps (P = 0.01). Birth intervals tended to increase with increasing EBVps (P = 0.10) and duration of farrowing was not related to EBVps. Time until first teat in mouth increased with increasing EBVps (P = 0.05), but the other behavioral indicators of pig vitality were not related to EBVps. Rectal temperature within 24 h after birth was not related to EBVps. Pigs with a higher genetic merit for survival have a lower birth weight but nevertheless have an increased farrowing survival and early postnatal survival. Their increased survival cannot be explained by differences in progress of farrowing, early postnatal behavior, or rectal temperature within 24 h after birth.

Animals↗

PubMed1991

Growth hormone concentrations in plasma of healthy pigs and pigs with atrophic rhinitis.

Plasma concentrations of porcine growth hormone (PGH) were similar in healthy pigs and those with atrophic rhinitis (AR), therefore, observed reduced growth rates and feed efficiency in naturally infected pigs with AR were not attributed to low concentrations of plasma PGH. Also, pituitary glands in both groups of pigs were responsive to growth hormone-releasing hormone (GHRH) challenge by increasing PGH secretion. Administration of clonidine hydrochloride to pigs naturally infected with AR failed to elicit any significant change (5.3 +/- 1.4 ng/ml) in the plasma concentration of PGH within a 45-minute bleeding interval. The pretreatment concentrations of PGH were similar in specific-pathogen-free toxin-treated and specific-pathogen-free control groups, but they increased significantly in toxin-treated pigs (20.7 +/- 8.2 ng/ml) within 15 minutes after GHRH injection. Porcine growth hormone release in toxin-treated pigs was variable; however, all pigs did not respond to GHRH administration: 3 responded with an increase in PGH release (35.6 +/- 10.6 ng/ml), 2 did not respond (6.7 +/- 0.5 ng/ml), and 1 had a decrease in PGH release (3.9 ng/ml). Therefore, the observed reduced growth rates reported in the literature may be attributed to factors at the target level of PGH action, such as insufficient or down-regulation of PGH receptors, changes or impaired ability in the PGH receptor-binding characteristics, and inability of PGH receptor complex to transduce signal. Toxins are known to modulate signal transduction pathways. It has been speculated that serotype-D Pasteurella multocida toxin may influence growth by its effect on signal transduction from PGH receptor complex on the cell membrane to the interior of the cell.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1988

[Hygienic aspects of pig's head meat. 1. Obtaining and processing pigs' heads].

Pigs's head meat is mainly obtained in specialised deboning plants and provides raw materials for the manufacture of meat products and snacks. Few data on hygiene in processing and production of pig's heads or on the bacteriological quality and tissue composition of pig's head meat have so far been published. The object of the present investigation was to supplement these data and to examine the extent to which this quality could be improved by Good Manufacturing Practices (GMP's). A total number of 11 slaughter-houses and 14 deboning plants were studied. Hygiene was assessed by two investigators on the basis of a check list. Temperatures of rooms, heads and head meat were measured. Twenty-one samples (7 x 3) were taken in each of nine deboning plants for bacteriological and histological examination. The investigations carried out in slaughter-houses showed that pig's heads were only washed in five out of eleven slaughter-houses. Cleansing and disinfection of the apparatus used in splitting the carcasses were omitted or merely carried out incidentally during slaughter. Assessment of hygiene in the deboning plants ranged from adequate to satisfactory in 13 out of 14 plants. The average aerobic colony count in Log N g-1 of pig's head meat was 6.7 +/- 0.7; this was 4.4 +/- 0.9 for counts of colony-forming units (CFU) of Enterobacteriaceae. Tonsils, mucous membranes, bone, hair and dirt were found to be present in 8, 13, 21, 39 and 9 per cent of the samples respectively. As a result of the manual cleavage of heads, relatively large bone particles (greater than 8 mm) were detected in the head meat. It is concluded that an improvement of the hygienic quality of pig's head meat can mainly be achieved by taking more care in obtaining pig's heads.

Abattoirs↗