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At least 487 records · Page 27Linked to original sources
PubMed1989

Immunological clearance of 75Se-labelled Trypanosoma brucei in goats.

An experiment was conducted to determine, under different conditions, the capacity of young adult East African goats to eliminate intravenously inoculated [75Se]selenomethionine-labelled Trypanosoma brucei from the bloodstream. Over 80% of labelled trypanosomes, preincubated for 1 h in inactivated normal goat serum, were detectable in the circulation 1 h after inoculation into normal goats. By contrast, after incubation in serum from goats which had been immunised against the homologous trypanosome clone, parasites were largely removed from the bloodstream within 5 min after inoculation. When the goats were necropsied 1 h after the inoculation of radiolabelled trypanosomes, 50% of the injected activity was found in the liver and lungs, the contribution of each organ being dependent to some extent on whether the inoculum was via a mesenteric or the jugular vein. The same result was obtained when labelled parasites were incubated in normal goat serum, and then inoculated into immunised goats; thus, rapid blood clearance occurred, and high activity was detected in the lungs and liver. The results confirm those of previous studies in laboratory mice in which the removal of trypanosomes from the circulation of an immune animal was achieved primarily by uptake of opsonised trypanosomes by elements of the mononuclear phagocytic system.

Animals↗
PubMed1993

Comparative pharmacokinetic behaviour of albendazole in sheep and goats.

Albendazole (ABZ) containing a trace of [14C]-ABZ was administered intraruminally at 4.75 mg kg-1 to Merino sheep and Angora goats and the pharmacokinetic behaviour of ABZ and its metabolites in plasma nd abomasal fluid compared. The systemic availability (area under the curve, AUC) for total [14C]-labelled metabolites was significantly lower in goats than in sheep. This was largely attributable to the disposition of ABZ sulphoxide (ABZ.SO) which had a significantly lower maximum concentration (Cmax) in goats (0.94 +/- 0.04 micrograms ml-1) than in sheep (1.41 +/- 0.24 micrograms ml-1). The AUC of [14C] in abomasal fluid was similar in goats and sheep, with approximately 35 and 45% of the dose passing the pylorus in the two species, respectively. ABZ, ABZ.SO and ABZ sulphone (ABZ.SO2) were present in the abomasal fluid of both species but between-species differences were only evident with ABZ.SO which had a lower Cmax in goats compared with sheep. The relative proportions of the [14C] dose excreted in urine and faeces were similar between species. It is suggested that ABZ may be sequestered to a greater extent in the liver of goats than of sheep which would result in lower concentrations of ABZ.SO in plasma and abomasal fluid. This behaviour might be compensated for by administering ABZ to goats at a proportionally higher dose rate.

Abomasum↗
PubMed1988

Social modulation of pituitary-adrenal responsiveness and individual differences in behavior of young domestic goats.

The effects of three variables known to influence pituitary-adrenal activity were examined in kid goats who were accompanied by adult goats in standard goat-human encounters. Serum corticosteroid concentrations in bold kids who characteristically spent above average amounts of time closely interacting with the person were never significantly different from control values. Corticosteroids in timid kids who spent little time near the person depended on the adult goat's behavior toward the person and the nature of the social relationship between the kid and the adult goat. When timid kids were accompanied by adult goats (familiar pen-mates or strangers) who behaved as if they were fearful of the person, their corticosteroids were significantly greater than control values. In contrast, bold pen-mates or bold strangers effectively reduced pituitary-adrenal responsiveness in timid kids. Only mothers unconditionally reduced kid pituitary-adrenal responsiveness and systematically affected kid behavior toward the person. The functioning of behavioral and pituitary-adrenal systems in young goats was influenced by consistent individual differences in responsiveness and the differing capacities of social companions to modulate this responsivity.

Adrenal Cortex Hormones↗
PubMed1994

Protection of goats against heartwater acquired by immunisation with inactivated elementary bodies of Cowdria ruminantium.

In two experiments, four and five goats were vaccinated by giving two subcutaneous injections of a preparation of inactivated elementary bodies of Cowdria ruminantium (Gardel stock) mixed with Freund's adjuvant. All vaccinated animals together with four naive controls were challenged intravenously with 5 ml of supernatant of a culture of bovine endothelial cells infected with the same stock of Cowdria. All goats developed a high temperature. Two out of four, and four out of five vaccinated goats survived the challenge whereas all naive control animals died within 7-12 days. Vaccinated goats which died survived longer than the controls. No difference in antibody titres was observed between protected and non-protected vaccinated goats. Moreover, immune sera from surviving goats, whether heat inactivated or not, were unable to neutralize the infection of bovine endothelial cells by Cowdria in vitro. Mechanisms conferring protection on the immunized goats are unknown at the moment but the hypothesis that T-helper lymphocyte populations have been elicited seems to be likely. This method of immunization with dead organisms will help in the search for protective antigens against cowdriosis.

Animals↗
PubMed1996

Responses to systemic angiotensin II in lactating and non-lactating goats.

This study aimed at investigating whether lactation affects the dipsogenic, hypertensive and volumetric effects of angiotensin II (Ang II) in a low-yielding goat adapted to arid conditions. Six black Moroccan goats were given intravenous infusions of Ang II at 8 ng kg-1 min-1 for 90 min during lactation and a non-lactation period. To further test the dipsogenic response, 5 of them were given Ang II at the consecutively increasing doses 10, 20, 50 and 100 ng kg-1 min-1 (10 min at each dose). The body weight was 32 +/- 1 kg in both periods and the daily milk production was 22 +/- 2 ml kg-1. No drinking was observed during infusions of Ang II in any of the goats. The rise of the mean arterial pressure to Ang II was attenuated in lactating animals and this was not steroid-dependent since the plasma progesterone level was low (< 0.2 nmol 1(-1)). Total plasma protein concentration decreased during Ang II infusions, and the ratio albumin/total proteins was unchanged, indicating that haemodilution had occurred. It is concluded that Ang II does not elicit drinking in the arid adapted Moroccan goats and we suggest that these goats have an elevated thirst threshold. However, haemodilution and an attenuated blood pressure response to Ang II occur in the lactating Moroccan goat, as has previously been observed in high-yielding Swedish domestic goats.

Angiotensin II↗
PubMed1984

Homeostatic responses to water deprivation or hemorrhage in lactating and non-lactating Bedouin goats.

Three lactating and three non-lactating black Bedouin goats were subjected to four days of water deprivation or to hemorrhage. Four days of water deprivation caused body wt losses of 32 and 23% and plasma volume losses of 30 and 34% in lactating and non-lactating goats respectively. Plasma osmolality increased 17 and 15% in lactating and non-lactating goats. Plasma arginine vasopressin concentration rose from about 5 pg/ml to a mean of 36 pg/ml. Plasma renin activity increased from about 0.7 ng/ml/hr to a mean of 3.45 ng/ml/hr in lactating and to 3.15 ng/ml/hr in non-lactating goats. At 4.5 hr post-rehydration plasma osmolality and plasma vasopressin concentration were back to normal in non-lactating, but still elevated in lactating goats. Plasma renin activity increased after rehydration. Rapid blood volume loss of 21-28% increased plasma vasopressin concentration to 16-35 pg/ml in non-lactating and to 70 or greater than 500 pg/ml in lactating goats. It is concluded that black Bedouin goats are well adapted to endure severe dehydration and rapid rehydration, but that they (especially lactating animals) react strongly to rapid volume depletion.

Animals↗
PubMed1990

Changes in mammary blood flow during the lactation period in goats measured by the ultrasound Doppler principle.

1. Mammary blood flow was measured during the lactation period in two low- and two high-yielding dairy goats (peak milk yields approx. 1.5 and 3.6 kg/day respectively), using the ultrasound Doppler principle for determination of blood velocity in both milk veins (subcutaneous abdominal veins) of the animals, and ultrasound scanning for measurement of cross-sectional area of the veins. 2. Milk vein cross-sectional area ranged from 0.11 to 0.38 cm2 in the four goats, with a close to significant (P = 0.06) difference between the veins in the two sides of the animals. Cross-sectional area remained constant during the lactation period. Changes in mammary blood flow was therefore caused by changes in blood velocity. 3. Milk vein blood velocities ranged from 4.4 to 34.7 cm/sec independently of the time of the day, and were of the same magnitude in the two sides of the animals. Except in one goat (P = 0.1), blood velocity decreased significantly (P less than 0.01) with progressing lactation, during which period also milk yield was declining. 4. In the two low-yielding goats, a positive linear relationship (R2 = 0.20) was found between milk yield and milk vein blood velocity, whereas a diminishing exponential relationship (R2 = 0.97) was found in the two high-yielding goats. At a given milk vein blood velocity, high-yielding goats obtained a higher milk yield and also responded to changes in blood velocity (up to approx. 15 cm/sec) with greater increases in milk yield than low-yielding goats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Heat stress causes excessive drinking in fed and food deprived pregnant goats.

Water intake was studied in six goats during late pregnancy to investigate if heat stress induces primary polydipsia. The goats were fed twice daily or deprived of food for 24 hr to avoid postprandial drinking and induce hyponatremia. Signs of stress was evaluated by determination of plasma cortisol concentration. Ambient temperature was increased from 20 degrees C to 38.0-39.5 degrees C for 5.15 hr. Water temperature was 35 +/- 1 degree C during heat stress. Fed goats started to drink 13 +/- 3 min after the heaters were turned on and water diuresis developed in five of them. The body weight increased simultaneously with decreased plasma Na concentration and osmolality showing that the goats also stored water. During food deprivation, plasma Na concentration and osmolality fell, and plasma aldosterone concentration increased. Despite hyponatremia, food deprived goats started to drink 44 +/- 15 min after the heaters were turned on and then they drank repeatedly. Three of them underwent water diuresis. Hemodilution was observed both in fed and food-deprived goats during heat stress. These results show that heat stress induced primary polydipsia in pregnant goats. It is suggested that stimulating signals from warmth receptors overrode inhibiting influences from receptors signalling hyponatremia and hypoosmolality at the "thirst center" in the hypothalamus. Heat stress did not increase plasma cortisol concentration, but catching sight of food caused an abrupt, short-lasting elevation.

Aldosterone↗
PubMed1996

Reproductive period affects water intake in heat-stressed dehydrated goats.

Water intake following dehydration was studied in pregnant (N = 5), lactating (N = 4) and nonpregnant, nonlactating (N = 5) Swedish domestic goats (Capra hircus) to investigate if reproductive period affected drinking. Plasma cortisol concentration and the hematocrit value were measured to evaluate stress. The goats were water deprived from 9.00 h until 15.05 h the next day. They were fed at 7.00 and 15.20 h. On the second day, ambient temperature was increased from 20 degrees C to 38-39.5 degrees C for 5.15 h to accelerate water losses. Water temperature during rehydration was 35 +/- 1 degree C. Plasma Na concentration and osmolality increased most in dehydrated and heat-stressed pregnant and lactating goats. Pregnant goats lost 2.2 kg of their body weight. They drank 3.5 l immediately, followed by 2.5 l during afternoon eating. Lactating goats lost 4.9 kg and drank 6.3 l at once, and 3.9 l during feeding. Nonpregnant, nonlactating goats lost 1.7 kg and drank 2.6 l followed by 0.6 l. The large water consumption in pregnant and lactating goats caused hyponatremia and hemodilution, but they continued to drink during the night (0.5 +/- 0.2 l and 0.8 +/- 0.5 l, respectively). Renal free water clearance increased in all periods, with a long-lasting water diuresis during pregnancy. Plasma cortisol concentrations and the hematocrit values rose in connection with water intake. These results imply that the thirst center became less sensitive to inhibitory signals from the oropharyngeal tract and the diluted blood plasma during pregnancy and lactation. Catching sight of water was the most exciting procedure during these experiments.

Animals↗
PubMed2005

Cloning and seasonal secretion of the pancreatic lipase-related protein 2 present in goat seminal plasma.

The storage of frozen semen for artificial insemination is usually performed in the presence of egg yolk or skimmed milk as protective agents. In goats, the use of skimmed milk extenders requires, however, that most of the seminal plasma is removed before dilution of spermatozoa because it is deleterious for their survival. It has been previously demonstrated that a lipase (BUSgp60) secreted by the accessory bulbourethral gland was responsible for the cellular death of goat spermatozoa, through the lipolysis of residual milk lipids and the release of toxic free fatty acids. This lipase was purified from the whole seminal plasma of goat and was found to display both lipase and phospholipase A activities, this latter activity representing the main phospholipase activity detected in goat seminal plasma. Based on its N-terminal amino acid sequence, identical to that of BUSgP60 purified from bulbourethral gland secretion, and the design of degenerated oligonucleotides, the lipase was cloned from total mRNA isolated from bulbourethral gland. DNA sequencing confirmed it was the goat pancreatic-lipase-related protein 2 (GoPLRP2). The physiological role of GoPLRP2 is still unknown but this enzyme might be associated with the reproductive activity of goats. A significant increase in lipase secretion was observed every year in August and the level of lipase activity in the semen remained high till December, i.e., during the breeding season. A parallel increase in the plasmatic levels of testosterone suggested that GoPLRP2 expression might be regulated by sexual hormones. The lipase activity level measured in goat seminal plasma, which could reach 1000 U/ml during the breeding season, was one of the highest lipase activity measured in natural sources, including gastric and pancreatic juices.

Amino Acid Sequence↗
PubMed2006

Factors derived from mouse embryonic stem cells promote self-renewal of goat embryonic stem-like cells.

Goat embryonic stem (ES)-like cells could be isolated from primary materials-inner cell masses (ICMs) and remain undifferentiated for eight passages in a new culture system containing mouse ES cell conditioned medium (ESCCM) and on a feeder layer of mouse embryo fibroblasts (MEFs). However, when cultured in medium without mouse ESCCM, goat ES-like cells could not survive for more than three passages. In addition, no ES-like cells could be obtained when ICMs were cultured on goat embryo fibroblasts or the primary materials-whole goat blastocysts were cultured on MEFs. Goat ES-like cells isolated from ICMs had a normal karyotype and highly expressed alkaline phosphatase. Multiple differentiation potency of the ES-like cells was confirmed by differentiation into neural cells and fibroblast-like cells in vitro. These results suggest that mouse ES cells might secrete factors playing important roles in promoting goat ES-like cells' self-renewal, moreover, the feeder layers and primary materials could also influence the successful isolation of goat ES-like cells.

Animals↗
PubMed2005

Effects of low concentrations of dietary cobalt on liveweight gains, haematology, serum vitamin B(12) and biochemistry of Omani goats.

Seventy-three, 10-week-old, newly weaned Omani goats of three different breeds, namely Dhofari (D), Batinah (B) and Jebel Akhdar (JA) were randomly divided into a control (n=38) and a treated group (n=35) for an experimental period of 10 months. Goats in both groups were fed 150 g/day per head of a pelleted concentrate, based on body weight and their requirements and Rhodes grass hay ad libitum, containing 0.12 and 0.10 mg/kg DM cobalt, respectively. Goats in the treated group also received bi-monthly subcutaneous injections of 2000 microg hydroxycobalamin. In contrast to the treated goats, the control animals of all breeds experienced a severe decrease in their serum vitamin B(12) levels, developed pale mucous membranes, appeared scruffy and two breeds (D and B) had significantly lower weight gains from month 5. Untreated kids of all breeds had significant decreases in their red blood cell counts and erythrocyte indices after approximately four months. Controls developed low total serum protein levels whilst activities of alkaline phosphatase and aspartate aminotransferase significantly increased. Although it is widely assumed that goats are more resistant to cobalt deficiency than sheep this is apparently not true for Omani goats. Based on experimental data from previously reported studies and those from the present study it can be concluded that the reduction in weight gains in D and B goats is related to their lower digestibility coefficients for dry matter, crude protein and energy while the increase in alkaline phosphatase and aspartate aminotransferase are associated with developing hepatic lipidosis.

Animal Feed↗
PubMed2005

Serotypes, virulence genes and intimin types of verotoxin-producing Escherichia coli and enteropathogenic E. coli isolated from healthy dairy goats in Spain.

Faecal samples from 222 healthy dairy goats on 12 farms in Spain, as well as bulk tank milk samples of these farms, were screened for the presence of verotoxin-producing Escherichia coli (VTEC) and enteropathogenic E. coli (EPEC). VTEC and EPEC were isolated in 47.7 and 7.7% of the animals, respectively. VTEC were isolated more frequently from adults and replacement animals than from goat kids. In contrast, EPEC were detected more frequently from goat kids than from replacement animals and adults. VTEC or EPEC strains were not detected in the bulk tank milk samples. Although a selective enrichment protocol was used, the serotype O157:H7 was not detected. The most frequent serotypes among the 106 VTEC strains isolated from goats were O5:H-, O76:H19, O126:H8, O146:H21, ONT:H- and ONT:H21. None VTEC strain was eae-positive. The absence of the eae gene in the VTEC strains could indicate that these strains are less virulent for humans that the classical eae-positive enterohaemorrhagic E. coli types. However, 16% of VTEC strains isolated from healthy goats belonged to serotypes associated with haemolytic uraemic syndrome in humans. The ehxA gene was detected in 84.9 and 52.9% of the VTEC and EPEC from goats, respectively. The beta1, theta/gamma2 and zeta were the most frequent intimin types among the 17 EPEC strains studied and the most prevalent serotypes of these strains were O156:H25 and O177:H11. Our data show that in Spain healthy goats are an important reservoir of VTEC and EPEC, and a potential source of infection for humans.

Adhesins, Bacterial↗
PubMed2000

The seroprevalence of antibodies to toxoplasma gondii in domestic goats in Uganda.

Only limited epidemiological information is available on the seroprevalence of Toxoplasma gondii in domestic livestock in sub-Saharan Africa. In Uganda, goats are important to the local economy and are also popular food animals. A high incidence of T. gondii infection in goats would have implications both for animal production and for public health, but no data is available on Toxoplasma infection in these animals. In this study we estimated the seroprevalence of antibodies against T. gondii in goats located in both urban and rural environments and from different geographical regions within Uganda. Goat sera were collected using a random, two-stage clustering method. Of 784 samples analysed by antibody-ELISA from various districts in Uganda, 240 tested positive. The combined (cluster-adjusted) seroprevalence was 0.31 (31%) (95% confidence intervals 0.28, 0.34) indicating a substantial level of infection in these regions. Seroprevalence was significantly higher in goats from urban locations. A strong positive relationship between age and seroprevalence was demonstrated and a mathematical model based on continuous exposure proved generally accurate in predicting seroprevalence. Farm environments were identified as being suitable for oocyst survival and transmission, and the reported incidence of caprine abortion was high. The importance of toxoplasmosis to goat production in Uganda has yet to be determined, but the high seroprevalence detected in this study suggests that it may have a significant impact and that the consumption of goat meat may play a role in zoonotic transmission to humans.

Animals↗
PubMed2000

Role of nitric oxide in vascular tone and in reactivity to isoproterenol and adenosine in the goat coronary circulation.

The present study examined the role of nitric oxide in coronary vascular tone and in the coronary vasodilatation in response to beta-adrenoceptor stimulation and adenosine. In anesthetized goats, the effects of intracoronary and i.v. administration of the inhibitor of nitric oxide synthesis, N(w)-nitro-L-arginine methyl ester (L-NAME), and those of isoproterenol, adenosine and acetylcholine on coronary blood flow, measured electromagnetically in the left circumflex coronary artery, were recorded. Intracoronary infusion of L-NAME (30-40 microg kg(-1) min(-1), four goats) reduced resting coronary blood flow by 14+/-3% (P<0.05) without changing arterial pressure and heart rate. L-NAME (40 mg kg(-1), eight goats) i.v. reduced resting coronary blood flow by 19+/-4% (P<0.05), increased mean systemic arterial pressure by 22+/-3% (P<0.01) and decreased heart rate by 10+/-2% (P<0.05). These effects of L-NAME were partially, but significantly reversed by L-arginine (six goats). Isoproterenol (10-100 ng, eight goats), adenosine (0.3-10 microg, seven goats) and acetylcholine (3-100 ng, five goats), injected intracoronarily, increased coronary conductance in a dose-dependent way and, under control conditions, these increases for isoproterenol, ranged from 32+/-5% to 82+/-12%; for adenosine, 6+/-2% to 174+/-22%; and for acetylcholine, 39+/-5% to 145+/-15%. During i.v. L-NAME the increases in coronary conductance induced by isoproterenol and acetylcholine were significantly reduced by about 50 and 60% (P<0.05), respectively, whereas those induced by adenosine were significantly increased further (about 30-100%, P<0. 05). During L-NAME plus L-arginine, the effects of isoproterenol, acetylcholine and adenosine on coronary conductance were not significantly different from those under control conditions. Therefore, it is suggested that in the coronary circulation: (a) nitric oxide may produce a basal vasodilator tone under normal conditions; (b) nitric oxide may be an intermediate in the vasodilatation due to beta-adrenoceptor stimulation and acetylcholine, and (c) the vasodilatation due to adenosine is potentiated during reduction of nitric oxide production.

Acetylcholine↗
PubMed1999

Characterization of a pig-to-goat orthotopic lung xenotransplantation model to study beyond hyperacute rejection.

BACKGROUND: A pig-to-goat orthotopic lung xenograft model was developed to test whether depletion of goat xenoreactive antibodies against pig red blood cells would prolong pig lung xenograft survival. METHODS: Adult goats with anti-pig xenoreactive antibodies underwent left pneumonectomy followed by orthotopic transplantation of pig left lung (group 1) or immunodepletion of their xenoreactive antibodies by extracorporeal right pig lung perfusion before transplantation without (group 2) or with (group 3) complete clampage of the right pulmonary artery. In group 4, goat left lungs were orthotopically transplanted into pigs and served as negative controls (pig serum does not have anti-goat xenoreactive antibodies). Each study group included 5 animals. Immunosuppression in surviving recipients included cyclosporine and azathioprine. RESULTS: Group 1 recipients died 7 +/- 3 hours after xenograft reimplantation of severe pulmonary hypertension and dysfunction and vasogenic shock, with little evidence of histologic xenograft injury. Group 2 xenografts had a stable circulatory and respiratory function on reperfusion and survived 9 +/- 4 days. Group 3 animals also tolerated complete occlusion of the right pulmonary artery, and xenografts assured the total respiratory support for 4 +/- 1 days. After immunodepletion, goat serum showed no detectable titers of xenoreactive antibodies, which began to reappear by postoperative day 2, where xenografts showed histologic stigmata of acute (humoral and cellular-mediated) rejection that evolved to a complete xenograft necrose at death. Group 4 xenografts showed scattered features of acute rejection 5 +/- 1 days after the operation. CONCLUSIONS: Pig left lung xenografts can provide prolonged and complete respiratory support after depletion of goat xenoreactive antibodies, but they ultimately necrose once recipient xenoreactive antibodies return to pretransplantation values.

Animals↗
PubMed2000

Roles of pulsatile release of LH in the development and maintenance of corpus luteum function in the goat.

The roles of the pulsatile release of LH in the functional development and maintenance of the corpus luteum (CL) during the estrus cycle in the goat were examined using a potent GnRH antagonist. In Experiment 1, to assess the inhibitory effects of the GnRH antagonist on the release of LH during the estrus cycle, 9 goats were divided into 3 groups. Goats in Group I received only saline on Days 0 (day of ovulation), 5, 10 and 15. Goats in Group II received the GnRH antagonist (50 microg/kg, s.c.) on the days mentioned for Group I to inhibit endogenous LH during the periods of luteal development and maintenance. Goats in Group III received saline on Days 0 and 5 and then the GnRH antagonist on Days 10 and 15 to inhibit LH during the period of luteal maintenance. Serial blood sampling took place on Days 1, 3, 5, 8, 13 and 18 to characterize the LH pulses. The LH pulses were observed throughout the estrus cycle in Group I but were completely abolished in Group II. In Group III, the pulsatile release of LH was observed from Day 1 to 8, but the LH pulses were completely abolished on Days 13 and 18. In Experiment 2, 16 goats were divided into the same 3 groups as in Experiment 1 to examine the effects of the GnRH antagonist on the luteal function. The concentration of progesterone in the plasma in Group I increased after ovulation, reached a maximum level around Day 12, and subsequently returned to the basal level on Day 17. The concentrations of progesterone in Group II rose after ovulation, but reached a plateau around Day 6 and maintained the level up to Day 9, then rapidly decreased from Day 9 to 10 to the basal level. The concentrations of progesterone in Group II were lower on Days 7 to 15 than those in Group I (P<0.01). The concentrations of progesterone in Group III increased after ovulation, reached a maximum level around Day 8, then dropped from Day 10 to 13 to the basal level. The concentrations of progesterone in Group III on Days 11 to 15 were lower than those in Group I (P<0.05 on Day 11, P<0.01 on Days 12 to 15). These results demonstrate that endogenous LH is essential for normal development and maintenance of the CL function during the estrus cycle in the goat. Further, this study suggests that while the functional maintenance of the caprine CL depends entirely on LH support, such functional dependence during early CL development is only partial.

Animals↗
PubMed1998

Body weight, oestrous and ovarian activity in local Burundian ewes and goats after parturition in the dry season.

To compare body weight losses and post-partum anoestrus, twelve local Burundian ewes and twelve goats which had lambed or kidded at the middle of the dry season were followed from parturition until eight months. Each dam was weighed every month and bled three times a week to assess the ovarian activity resumption by plasma progesterone (P4) profiles. For the two species, the body weight decreased significantly (P < 0.05) compared to the body weight at parturition. The mean time during which the body weight decreased was longer (P < 0.05) for the ewes (3.2 +/- 1.2 months) than for the goats (2.3 +/- 1.4 months), however, the relative body weight losses did not significantly differ. The time to oestrous and ovarian activity resumption was highly correlated to the body weight losses for the ewes (r = 0.81; P < 0.01 and r = 0.58; P < 0.05) not for the goats. The first oestrus preceded the first ovarian activity by 4 days in the goats, but occurred 36 days later in the ewes. Nevertheless, after the first luteal function, the subsequent ovarian activity was regular and normal in the ewes but not in the goats and in some cases a return to anoestrus could be observed. These data indicate that in the ewe, not in the goat, the body weight losses are one of the major limiting factors of the oestrous and ovarian resumption after parturition during the dry season. Moreover, the occurrence of luteal function does not initiate a regular reproductive cyclicity in the goat in contrast to the ewes.

Analysis of Variance↗