Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “GOATS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 289 records · Page 16Linked to original sources
PubMed2004

Effect of fluorogestone acetate on embryo recovery and quality in eCG-superovulated goats with premature luteal regression.

The objective of this study was to evaluate if treatment of eCG-superovulated goats with fluorogestone acetate (FGA) would increase the number and quality of embryos recovered. Goats (n = 25) were given an intravaginal sponge containing 45 mg FGA for 12 days, with 1000 IU eCG and 7.5mg of Luprostiol (a PGF(2 alpha) analog) given -48 and 0 h relative to sponge removal. Goats were mated by natural service every 12h during estrus and surgical embryo collection was done 6 days after the last mating. There were two treatment groups; those in the FGA group (n = 13) had a FGA sponge from 8h after mating to embryo collection, whereas goats in the control group (n = 12) did not receive any post-mating treatment. Premature luteal regression occurred in 61.5% (8/13) and 83.3% (10/12) of the goats in the FGA and the control groups, respectively (P > 0.05). Corpus luteum life span averaged 4 days in goats with premature luteolysis. The mean (+/- S.E.) number of transferable embryos was 5.7 +/- 1.6 in the FGA group and 0.1 +/- 0.1 in the control group (P < 0.05). Within the FGA group, the embryo recovery rate was similar in goats with premature luteal regression compared to those with normal luteal function, although non-transferable embryos were only found in goats with premature luteal regression. In conclusion, post-breeding treatment with FGA increased embryonic survival in eCG-superovulated goats, even though it did not prevent premature luteal regression.

Administration, Intravaginal↗
PubMed2005

Effect of roscovitine on nuclear maturation, MPF and MAP kinase activity and embryo development of prepubertal goat oocytes.

The low number of embryos obtained from IVM-IVF-IVC of prepubertal goat oocytes could be due to an incomplete cytoplasmic maturation. Roscovitine (ROS) inhibits MPF and MAP kinase activity and maintains the oocyte at Germinal Vesicle (GV) stage. The aim of this study was to determine if meiotic activity is arrested in prepubertal goat oocytes cultured with 0, 12.5, 25, 50 and 100 microM of ROS for 24 h. A group of oocytes from adult goats was cultured with 25 microM of ROS to compare the effect of ROS on prepubertal and adult goat oocytes. A sample of oocytes was stained to evaluate the nuclear stage at oocyte collection time and after ROS incubation. IVM-oocytes not exposed to ROS formed the control group. Prepubertal goat IVM-oocytes were inseminated and cultured for 8 days. The percentage of oocytes at GV stage, after exposition to ROS was significantly higher in adult goat oocytes (64.5%) than in prepubertal goat oocytes. No differences were found among 25, 50 and 100 microM ROS concentrations (29, 23 and 26%, oocytes at GV stage, respectively). After 8 days of culture, no differences in total embryos were observed between control oocytes and oocytes treated with 12.5 and 25 microM (45.2, 36.1 and 39.4%, respectively), however the percentage of blastocysts was higher in the control group. Western blot for the MAPK and p34(cdc2) showed that both enzymes were active in prepubertal goat oocytes after 24h of ROS exposition. In conclusion, a low percentage of prepubertal goat oocytes reached GV stage after ROS incubation; possibly because most of them had reinitiated the meiosis inside the follicle. ROS did not affect fertilization or total embryos but ROS showed a negative effect on blastocyst development.

Animals↗
PubMed2005

Mitochondrial diversity and phylogeographic structure of Chinese domestic goats.

China has numerous native domestic goat breeds, but so far there has been no extensive study on genetic diversity, population demographic history, and origin of Chinese goats. Here, we examined the genetic diversity and phylogeographic structure of Chinese domestic goats by determining a 481-bp fragment of the first hypervariable region of mitochondrial DNA (mtDNA) control region from 368 individuals representing 18 indigenous breeds. Phylogenetic analyses revealed that there were four mtDNA lineages (A-D) identified in Chinese goats, in which lineage A was predominant, lineage B was moderate, and lineages C and D were at low frequency. These results further support the multiple maternal origins of domestic goats. The pattern of genetic variation in goat mtDNA sequences indicated that the two larger lineages A and B had undergone population expansion events. In a combined analysis of previously reported sequences and our sequences belonging to lineage B, we detected two subclades, in which one was unique to eastern Asia and another was shared between eastern and southern Asia. A larger genetic variation in eastern Asia than southern Asia and the pattern of phylogeographic variation in lineage B suggest that at least one subclade of lineage B originated from eastern Asia. There was no significant geographical structuring in Chinese goat populations, which suggested that there existed strong gene flow among goat populations caused by extensive transportation of goats in history.

Animals↗
PubMed2000

Regional distribution of gonadotropin-releasing hormone-like, beta-endorphin-like, and methionine-enkephalin-like immunoreactivities in the central nervous system of the goat.

Regional distribution of gonadotropin-releasing hormone (GnRH)-like-, beta-endorphin (beta-end)-like-, and methionine-enkephalin (met-enk)-like-immunoreactivity was quantified across various regions of the central nervous system (CNS) of male and female goats by using highly specific radioimmunoassays. All the animals were sacrificed during the months of March through June (non-breeding season). Although the distribution of these three neuropeptides was similar to other mammalian species, species-specific gender differences in the levels of neuropeptides were noticed in the goat CNS. Highest levels of GnRH-like immunoreactivities were found in the hypothalamus. The hypothalamus of male goats exhibited significantly higher levels of GnRH-like immunoreactivities compared to female goats. Other regions exhibiting GnRH-like immunoreactivities included olfactory bulbs, preoptic and supraoptic regions, and mamillary bodies. Both beta-end- and met-enk immunoreactivities were detected in all selected regions of goat CNS, but highest levels of these opioid peptide-like immunoreactivities were limited to the forebrain regions of the goat. The supraoptic area of the female goats contained significantly higher levels of beta-end-like immunoreactivities than that of the male goats. Met-enk-peptide-like immunoreactivity also exhibited gender-specific differences in its content in some regions of the CNS. The male goats exhibited significantly higher levels of met-enk-like immunoreactivity in both the striatal and hypothalamic regions of the brain.

Analysis of Variance↗
PubMed1975

Studies on the milk composition of West African dwarf, Red Sokoto and Saanen goats at different stages of lactation. I. Total solids, butterfat, solids-not-fat, protein, lactose and energy contents of milk.

Nine West African dwarf (Fouta djallon), Red Sokoto (Maradi) and Saanen lactating goats, hand-milked, were used for these studies, which lasted 12 weeks. The Saanen goat's milk was obtained weekly from the Western State Ministry of Agriculture and Natural Resources Urban Dairy Farm at Iwo Road, while similar samples were collected from the herd at the University of Ibadan Teaching and Research Farm. The goats were balanced for stage of lactation, namely early, mid- and late-lactation. They were each maintained on giant star grass (Cynodon nlemfuensis) ad lib. and 1 kg dairy concentrate mixture daily. The mean contents, with standard deviations, of the milks of Saanen, West African dwarf and Red Sokoto goats at mid-lactation respectively were: (in percentages), total solids 12-25 plus or minus 0-078, 18-18 plus or minus 0-392, 15-85 plus or minus 0-077; solids-not-fat (SNF) 8-91 plus or minus 0-42, 10-48 plus or minus 0-471, 10-53 plus or minus 0-140; butterfat 3-34 plus or minus 0-141, 7-78 plus or minus 0-621, 5-32 plus or minus 0-098; protein 3-04 plus or minus 0-139, 5-30 plus or minus 0-292, 4-74 plus or minus 0-021; lactose 4-56 plus or minus 0-167, 5-19 plus or minus 0-176, 4-77 plus or minus 0-053; energy (kj/g dried milk), 21-08 plus or minus 1-11, 25-51 plus or minus 1-74, 22-17 plus or minus 0-51. Breed differences were significant (P less than 0-01). The milk of West African dwarf goats contained more of these milk components than the milk of the Red Sokoto or Saanen goats. The Red Sokoto goats gave milk of higher content than did Saanen goats, even at an early stage of lactation. Butterfat, protein, lactose and energy values were significantly affected by stages of lactation (P less than 0-05) and tended to rise with advancing lactation; this was particularly so with West African dwarf goats.

Animal Feed↗
PubMed2002

Changes in blood glucose, plasma non-esterified fatty acids and insulin in pregnant and non-pregnant goats.

The blood glucose and the plasma non-esterified fatty acids (NEFA) and insulin concentrations were estimated in jugular blood samples from 18 Alpine x Beetal and Sannen x Beetal goats during pregnancy and compared with samples from non-pregnant goats and from goats during the periparturient period. The blood glucose levels in the pregnant goats rose to a peak of about 60 +/- 1.36 mg/ml at 42-56 days and then declined to about 46 +/- 2.37 mg/ml at 112-126 days. In non-pregnant goats, the blood glucose levels were significantly (p < 0.01) higher than in pregnant goats, except between days 42 and 70 (59 +/- 1.36 mg/ml). On the day of kidding, the levels declined significantly (p < 0.01), increasing again thereafter. The plasma NEFA concentrations were significantly higher in pregnant than in non-pregnant goats from days 56 to 126. The NEFA concentration increased on the day of kidding, followed by a transient fall by day 3. The plasma insulin concentration was usually higher in pregnant than in non-pregnant goats, except between days 56 and 70 and from day 126 onwards. The insulin concentration fell late in pregnancy, but there was a transient increase 2 days after parturition. The blood glucose and plasma NEFA concentrations can be used as indices of nutritional status during pregnancy in goats.

Animals↗
PubMed1996

The preference for warm drinking water induces hyperhydration in heat-stressed lactating goats.

The aim of this study was to determine whether lactating goats regulate their water intake when given a choice between warm (35 degrees C) and cold (15 degrees C) water. Six lactating goats were kept individually in pens. At 07.00 h one bucket was filled with warm water and another with cold water. Water consumption was measured at intervals until 18.00 h. Water temperature was not controlled at night. Two experiments were made, one at normal room temperature (18-19 degrees C) and the other at 39-40 degrees C from 10.45 to 17.00 h. At normal room temperature the goats drank 6.0 +/- 1.4 L of the warm water but only 1.7 +/- 1.3 L of the cold water (P < 0.001). The total water consumption, including the following night, was 9.2 +/- 1.6 L. This differed from control days, when only cold water was available (5.9 +/- 0.4 L; P < 0.05). Neither the plasma Na concentration nor the osmolality changed, which indicate that the goats regulated their fluid balance. In the experiments involving heat stress the goats drank 11.5 +/- 1.7 L of the warm water but only 2.0 +/- 1.0 L of the cold water (P < 0.001). In total, including the following night, they drank 16.2 +/- 2.6 L (P < 0.001 vs. control days). Goats drank repeatedly despite falling plasma Na and osmolality, proving that their thirst was not induced by water losses. Their abdomens became distended, indicating that water was stored in the reticulo-rumen and explaining why their body weights increased. The goats appeared distressed. It is concluded that goats prefer to drink warm water. Nevertheless, our results suggest that, if possible, warm drinking water should not be given to lactating goats under hot ambient conditions.

Animals↗
PubMed2000

Effects of endotoxin-induced fever and probenecid on disposition of enrofloxacin and its metabolite ciprofloxacin after intravascular administration of enrofloxacin in goats.

Pharmacokinetics of enrofloxacin and its active metabolite ciprofloxacin were investigated in normal, febrile and probenecid-treated adult goats after single intravenous (i.v.) administration of enrofloxacin (5 mg/kg). Pharmacokinetic evaluation of the plasma concentration-time data of enrofloxacin and ciprofloxacin was performed using two- and one-compartment open models, respectively. Plasma enrofloxacin concentrations were significantly higher in febrile (0.75-7 h) and probenecid-treated (5-7 h) goats than in normal goats. The sum of enrofloxacin and ciprofloxacin concentrations in plasma > or =0.1 microg /mL was maintained up to 7 and 8 h in normal and febrile or probenecid-treated goats, respectively. The t1/2beta, AUC, MRT and ClB of enrofloxacin in normal animals were determined to be 1.14 h, 6.71 microg .h/mL, 1.5 h and 807 mL/h/kg, respectively. The fraction of enrofloxacin metabolized to ciprofloxacin was 28.8%. The Cmax., t1/2beta, AUC and MRT of ciprofloxacin in normal goats were 0.45 microg /mL, 1.79 h, 1.84 microg .h/mL and 3.34 h, respectively. As compared with normal goats, the values of t1/2beta (1.83 h), AUC (11.68 microg ? h/mL) and MRT (2.13 h) of enrofloxacin were significantly higher, whereas its ClB (430 mL/h/kg) and metabolite conversion to ciprofloxacin (8.5%) were lower in febrile goats. The Cmax. (0.18 microg /mL) and AUC (0.99 microg .h/mL) of ciprofloxacin were significantly decreased, whereas its t1/2beta (2.75 h) and MRT (4.58 h) were prolonged in febrile than in normal goats. Concomitant administration of probenecid (40 mg/kg, i.v.) with enrofloxacin did not significantly alter any of the pharmacokinetic variables of either enrofloxacin or ciprofloxacin in goats.

Animals↗
PubMed2004

Anaphylactic reaction to goat's milk in a cow's milk-allergic infant.

Goat's milk has been used as a substitute for cow's milk in cow's milk-allergic individuals. It is currently advocated for this purpose in writings and internet resources directed at the lay person, and infant formula based on goat's milk is available in many countries. Clinically significant cross-allergenicity between cow's and goat's milk has been noted, but a life-threatening cross-reaction has not been reported. We describe a 4-month-old infant with immunologically documented cow's milk protein allergy but no prior exposure to goat's milk who developed anaphylaxis after the ingestion of commercial goat's milk. Subsequent skin prick testing demonstrated a specific reaction to goat's milk. Thus, the cross-allergenicity between cow's and goat's milk proteins can lead to life-threatening complications. Individuals allergic to cow's milk protein should avoid goat's milk and goat's milk products.

Anaphylaxis↗
PubMed1999

Comparative pharmacokinetics of diminazene in lactating goats and sheep.

The pharmacokinetic aspects of diminazene aceturate were studied in lactating goats and sheep after single intravenous and intramuscular administrations of 3.5 mg/kg b.wt. Plasma and milk concentrations were determined by use of reversed phase high-performance liquid chromatography (HPLC) after ion-pair extraction. Following intravenous injection, the disposition of diminazene in goats and sheep conformed to a two-compartment model with rapid distribution and slower elimination phases. Values of (t1/2 beta) were obtained indicating a slower final disappearance of the drug from plasma of sheep (21.17 h) than in goats (16.39 h). Diminazene concentrations were maintained for more than 4 days in the plasma of goats and sheep. In both species of animals, diminazene was rapidly absorbed following intramuscular administration of 3.5 mg/kg b.wt. The peak plasma concentrations (Cmax) were 7.00 and 8.11 micrograms/ml and were attained at (Tmax) 0.92 and 1.12 hours in goats and sheep, respectively. The elimination half-life (t1/2el) of diminazene after intramuscular administration was shorter in goats (16.54 h) than in sheep (18.80 h). Systemic bioavailabilities (F%) of diminazene after intramuscular administration were 94.94% and 82.64% in goats and sheep, respectively. Diminazene could be detected in milk of goats and sheep within 10 min post-injection. Milk concentrations of the drug were lower in goats than in sheep and were detected for 5 and 6 days following both routes of administration, respectively.

Animals↗
PubMed1995

Effect of short photoperiodic cycles on male genital tract and testicular parameters in male goats (Capra hircus).

This study was performed in adult male goats in which seasonal variations were abolished by rapid alternations of long days and short days. These treatments have been shown previously to prevent seasonal changes in the hypothalamo-pituitary axis and to maintain testis weight and sperm production at a high level. The experimental groups were exposed for 3 years to an alternation of either a 1 month short (16 h dark; 8 h light) and 1 month long (16 L; 8 D) photoperiod (2 month cycle; n = 5) or of a 2 month short and 2 month long photoperiod (4 month cycle; n = 4). The control groups were maintained in natural photoperiodic conditions (45 degrees N) and goats were slaughtered in the non-breeding season (end of April RS; n = 5) at the same period as light-treated bucks, or in the breeding season (end of September BS; n = 6). The total weight of the testes, the length and mean diameter of the seminiferous tubules of light-treated goats were similar to those in the breeding season, and higher than those in the non-breeding season. The total number of A0 spermatogonia was increased by light treatments as compared to control goats in the breeding and non-breeding season. The daily production of A1 spermatogonia, leptonene primary spermatocytes and round spermatids in light-treated goats was maintained at the peak breeding season level. The intra-testicular concentration of testosterone, total volumes of intertubular tissue and of Leydig cells, and the number of Leydig cells per testis did not differ between groups. Although the mean cross-sectional area of Leydig cells in light-treated goats was similar to this area in non-breeding season goats, it was significantly lower than that of breeding season goats. In conclusion, the rapid alternation of short and long days allowed an increase in all the germ cells from the A0 spermatogonia onwards, which was responsible for the maintenance of high spermatogenetic activity of light-treated goats.

Animals↗
PubMed2001

Multiple maternal origins and weak phylogeographic structure in domestic goats.

Domestic animals have played a key role in human history. Despite their importance, however, the origins of most domestic species remain poorly understood. We assessed the phylogenetic history and population structure of domestic goats by sequencing a hypervariable segment (481 bp) of the mtDNA control region from 406 goats representing 88 breeds distributed across the Old World. Phylogeographic analysis revealed three highly divergent goat lineages (estimated divergence >200,000 years ago), with one lineage occurring only in eastern and southern Asia. A remarkably similar pattern exists in cattle, sheep, and pigs. These results, combined with recent archaeological findings, suggest that goats and other farm animals have multiple maternal origins with a possible center of origin in Asia, as well as in the Fertile Crescent. The pattern of goat mtDNA diversity suggests that all three lineages have undergone population expansions, but that the expansion was relatively recent for two of the lineages (including the Asian lineage). Goat populations are surprisingly less genetically structured than cattle populations. In goats only approximately 10% of the mtDNA variation is partitioned among continents. In cattle the amount is >/=50%. This weak structuring suggests extensive intercontinental transportation of goats and has intriguing implications about the importance of goats in historical human migrations and commerce.

Animals↗
PubMed1996

The effects of condensed tannins from Desmodium intortum and Calliandra calothyrsus on protein and carbohydrate digestion in sheep and goats.

A factorial experiment was conducted to study the effects of condensed tannins (CT) from the tropical legumes Desmodium intortum and Calliandra calothyrsus on the digestion and utilization of protein and carbohydrate in sheep and goats. CT-free Centrosema pubescens was also fed for comparison with the CT legumes, and each legume was included (300 g/kg DM) in a basal diet of pangola grass (Digitaria decumbens). Pangola grass alone was used as a control diet. There were no significant (P > 0.05) differences between sheep and goats for the efficiency of digestion of N (0.574, SE 0.013), organic matter (OM; 0.519, SE 0.010), neutral-detergent fibre (NDF; 0.524, SE 0.011) and acid-detergent fibre (ADF; 0.407, SE 0.016). Diets containing desmodium and calliandra were digested less well in the rumen (64 and 62% of total OM digested) when compared with the pangola and centrosema diets (74 and 73% of total OM digested in rumen). There was an apparent net gain of 30% in ADF across the digestive tract of sheep and goats given calliandra, and this gain was ascribed to the formation of 'artifact' fibre as a result of fibre-tannin interaction. Overall, inclusion of legume at 300 g/kg in the diet significantly increased (P < 0.05) the concentration of acetic acid and decreased butyric acid concentration in the rumen fluid of sheep and goats. Significantly higher proportions of dietary N apparently reached the abomasum of animals given the diets containing desmodium (50%) and calliandra (56%) when compared with animals given the centrosema and pangola diets (35%). Sheep and goats given the CT diets also had higher excretions of faecal N. This increment of faecal N (14%) did not affect post-rumen N digestion (P > 0.05) since animals given CT diets absorbed more N (19%) per kg total OM digested than those given the control diets. It was concluded that whilst the low levels of CT provided in desmodium (1.0%) and calliandra (2.3%) diets protected dietary protein from degradation in the rumen, there were no overall beneficial or detrimental effects of CT in these diets for sheep or goats. A method was developed to categorize CT into fractions representative of their forms (free, protein-bound, and fibre-bound) during the digestion process. A quantitative model of CT metabolism during passage through the digestive tract was developed from the measured exchanges of CT between free, protein-bound and fibre-bound pools in the rumen and lower digestive tract. CT interchange mainly occurred in the reticulo-rumen of both animal species. Desmodium and calliandra free CT showed net losses of 68 and 78% in the rumen respectively and 57 and 68% of the fibre-bound CT was lost in the same site for sheep and goats respectively. However, protein-bound CT increased across the rumen by 73 and 56% for both animal species. Post-rumen losses of the total CT abomasal flow were 86 and 83% (free CT) for sheep and goats respectively, 70 and 66% (protein-bound CT), whilst 28% loss of fibre-bound CT occurred in sheep and goats respectively.

Animals↗
PubMed1996

A genetic linkage map of the male goat genome.

This paper presents a first genetic linkage map of the goat genome. Primers derived from the flanking sequences of 612 bovine, ovine and goat microsatellite markers were gathered and tested for amplification with goat DNA under standardized PCR conditions. This screen made it possible to choose a set of 55 polymorphic markers that can be used in the three species and to define a panel of 223 microsatellites suitable for the goat. Twelve half-sib paternal goat families were then used to build a linkage map of the goat genome. The linkage analysis made it possible to construct a meiotic map covering 2300 cM, i.e., > 80% of the total estimated length of the goat genome. Moreover, eight cosmids containing microsatellites were mapped by fluorescence in situ hybridization in goat and sheep. Together with 11 microsatellite-containing cosmids previously mapped in cattle (and supposing conservation of the banding pattern between this species and the goat) and data from the sheep map, these results made the orientation of 15 linkage groups possible. Furthermore, 12 coding sequences were mapped either genetically or physically, providing useful data for comparative mapping.

Animals↗
PubMed1966

Calcium metabolism in normal and thyro-parathyroidectomized goats.

1. The effects of thyro-parathyroidectomy on calcium metabolism in the goat have been investigated using stable calcium balance techniques and the isotopes (45)Ca, (47)Ca and (85)Sr.2. Thyro-parathyroidectomized goats, whether receiving supplementary thyroxine or not, are in negative calcium balance, whereas normal or thyroidectomized animals are in positive balance.3. Gastro-intestinal absorption of (45)Ca is less in thyro-parathyroidectomized goats, whether receiving supplementary thyroxine or not, than in either normal goats or thyroidectomized goats receiving thyroxine supplements.4. The rate of endogenous secretion of calcium into the gastro-intestinal tract is unchanged by either thyroidectomy or thyro-parathyroidectomy. Urinary excretion of calcium is also apparently unchanged.5. The bone calcium accretion rate is reduced to approximately the same extent in thyroidectomized and thyro-parathyroidectomized goats. Thyroxine supplements restore the bone accretion rate of both groups of animals to normal or greater than normal levels.6. The bone calcium resorption rate is greater in thyro-parathyroidectomized goats, whether receiving thyroxine supplements or not, than in either normal goats or thyroidectomized goats receiving thyroxine supplements.

Animals↗
PubMed1987

Injection site reactions and antibody responses in sheep and goats after the use of multivalent clostridial vaccines.

Uncertainty concerning the use, efficacy and possible adverse effects of clostridial vaccination in goats prompted a study of the injection site reactions and antibody responses in 40 goats and 40 sheep. The vaccines used were Covexin 8, Heptavac and Tasvax 8. In all the animals swellings averaging 2.5 cm in diameter were present at the injection site seven days after vaccination and were still apparent 28 days after vaccination. The injection site reactions could not be attributed to faulty vaccination technique because they did not occur in a control group injected with sterile water. By 14 days the reactions were significantly larger in sheep than in goats and by 28 days the reactions to Covexin 8 were larger than those to the other vaccines in sheep and goats. Serum antibody was present in all groups before vaccination and, with the exception of the goats vaccinated with Heptavac, increased 14 days after vaccination. The increase was greater in sheep than in goats. By 28 days antibody levels had declined in all but the sheep vaccinated with Heptavac in which a further increase occurred. At that time, the antibody levels in vaccinated sheep were still higher than in the unvaccinated sheep whereas the antibody levels in vaccinated goats were no longer different from those in the control goats. These results suggest that there is a difference between the vaccines used and between the responses of the two species and support the clinical observation that the protection afforded to goats by multivalent clostridial vaccines is poorer than that afforded to sheep.

Animals↗
PubMed1991

Pulmonary hemodynamic reaction to foreign blood in goats and rabbits.

We have found that the goat is extraordinarily sensitive to very small quantities of rabbit or rat blood. As little as 0.004 ml/kg induces transient pulmonary hypertension [maximal rise in pulmonary arterial pressure 32 +/- 10 (SD) cmH2O] in goats. We hypothesized that this reaction may be related to the presence of the resident population of intravascular macrophages that reside in the pulmonary capillaries of goats. If that is so, then rabbits or rats, which have few or no intravascular macrophages, should not be reactive to foreign blood. We compared pulmonary hemodynamics and changes in blood thromboxane B2 concentrations among goats, rabbits, and rats in response to graded doses of foreign blood. The pulmonary reaction to foreign blood was much greater in goats than in rabbits or rats, even though we injected up to 10- or 60-fold larger amounts into the latter species. In goats the pulmonary vascular pressure response to rabbit blood was dose dependent in goats and correlated well with changes in systemic arterial thromboxane B2 concentrations [change in pulmonary arterial pressure = 0.07 (thromboxane B2) + 8.3, r = 0.79]. We also tested the prostaglandin H2 endoperoxide analogue (U-46619) and found that the goats are somewhat more reactive than rabbits. We conclude that the pulmonary hemodynamic reaction to foreign blood is consistent with the concept that the foreign erythrocytes are reacting with the pulmonary intravascular macrophages in goats. The lower reactivity of the rabbit pulmonary circulation to thromboxane may also have a role.

Animals↗
PubMed1999

Effect of carotid body denervation on breathing in neonatal goats.

The objective of the present study was to determine in goats whether carotid body denervation (CBD) at 1-3 days of age causes permanent changes in breathing greater than those that occur after CBD in adult goats. Goats underwent CBD (n = 6) or sham CBD (n = 3) surgery at 1-3 days of age. In addition, one unoperated control animal was studied. Bolus intravenous injections of NaCN 2 days postsurgery verified successful CBD surgery. However, at 3, 11, and 18 mo of age, the CBD goats had regained a NaCN response that did not differ (P > 0.10) from that of intact goats. Intracarotid NaCN injections elicited a hyperpnea in the sham CBD but not the CBD goats. Only one animal exhibited highly irregular breathing [characterized by prolonged (>9-s) apneas] after CBD, and the irregularity disappeared by 3 mo of age. One CBD goat died at 35 days of age, and autopsy revealed that death was associated with pneumonia. After 3 mo of age, there were no statistically significant differences (P > 0.10) between sham and CBD goats in eupneic breathing, hypoxia and CO(2) sensitivity, and the exercise hyperpnea. It is, therefore, concluded that CBD at 1-3 days of age in goats does not appear to affect selected aspects of respiratory control after 3 mo of age, conceivably because of the emergence of other functional chemoreceptors that compensate for the loss of the carotid chemoreceptor.

Animals↗