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1.
The present study aims to evaluate the effects of feeding palm oil by-products based diets on different muscle fatty acid profiles in goats. Thirty-two Cacang × Boer goats were randomly assigned to four dietary treatments: (1) control diet (CD), (2) 80% decanter cake diet (DCD), (3) 80% palm kernel cake diet (PKCD) and (4) CD plus 5% palm oil (PO) supplemented diet (CPOD). After 100 days of feeding, four goats from each group were slaughtered and longissimus dorsi (LD), infraspinatus (IS) and biceps femoris (BF) were sampled for analysis of fatty acids. Goats fed the PKCD had higher (P<0.05) concentration of lauric acid (C12:0) than those fed the other diets in all the muscles tested. Compared to the other diets, the concentrations of palmitic acid (C16:0) and stearic acid (C18:0) were lower (P<0.05) and that of linoleic acid (C18:2 n-6) was higher (P<0.05) in the muscles from goats fed the CD. It was concluded that palm kernel cake and decanter cake can be included in the diet of goats up to 80% with more beneficial than detrimental effects on the fatty acid profile of their meat.  相似文献   
2.
Molecular tools were used to evaluate the hybrid status of a specimen with intermediate colour pattern between Halichoeres bivittatus and Halichoeres garnoti from Belize. Phylogenetic analyses of the two species, eight Halichoeres species from new and old world lineages and two outgroups showed that the study species are closely related and that H. garnoti is the maternal contributor to the putative hybrid specimen, based on partial mitochondrial COI data. Direct sequencing of Intron 1 of the nuclear ribosomal protein S7 identified H. bivittatus as sister to H. garnoti with the putative hybrid specimen in an intermediate position, due to heterozygosity at nucleotides alternatively fixed in the two putative parent species. This is consistent with the hybrid status of the specimen, with parental contributions from both H. garnoti and H. bivittatus. These results, combined with no evidence of introgression between the two parent species (based on the mtDNA and the single investigated nuclear marker) and the biogeography and ecology of these species suggests that this is a rare event with minimal evolutionary implications.  相似文献   
3.
The objective of this study was to monitor and compare follicle populations and follicular development in pregnant and nonpregnant sows from Day 3 to Day 20 after breeding. Twenty-four sows were paired within parity on the day of artificial insemination and were randomly allocated within pair for insemination with either killed (n=12) or live spermatozoa (n=12). All the sows were artificially inseminated with the pooled ejaculate of the same boar. From Day 3 through Day 20 post estrus, ovarian follicles were scanned daily by ultrasonography. Ultrasound images were recorded on videotape and were retrospectively analyzed. Follicles were mapped to indentify the existence of follicular waves. The follicles were then classified as small (< 3 mm), medium (3-5 mm), or large (>/=5 mm). Pregnancy diagnosis was performed on Day 21 by ultrasonography. Pregnant sows maintained a constant proportion of the follicle population in the small, medium and large follicle categories. However, in the nonpregnant sows, the proportion of follicles in the various size categories remained constant until Day 15. Thereafter, the proportion of small follicles decreased (P < 0.05) from Day 15 to 20, and the proportions of medium and large follicles increased (P < 0.05). The predictability of pregnancy status on Day 20 based on follicle populations in any of the 3 follicle categories was low. Moreover, there was no evidence of follicular waves during the estrous cycle or early pregnancy. In conclusion, the proportion of small follicles decreased while medium and large follicle increased from Day 15 through Day 20 of the estrous cycle, but not during a similar stage of pregnancy. This latter finding concurs with follicle recruitment from the pool of small follicles for ovulation following PGF2alpha secretion to induce luteolysis, which reduces progesterone concentrations and thereby allows for the stimulation of the pool of small follicles by gonadotropins.  相似文献   
4.
Rumen microorganisms are responsible for digestion and utilization of dietary feeds by host ruminants. Unconventional feed resources could be used as alternatives in tropical areas where feed resources are insufficient in terms of quality and quantity. The objective of the present experiment was to evaluate the effect of diets based on palm oil (PO), decanter cake (DC) or palm kernel cake (PKC) on rumen total bacteria, selected cellulolytic bacteria, and methanogenic archaea. Four diets: control diet (CD), decanter cake diet (DCD), palm kernel cake diet (PKCD) and CD plus 5% PO diet (CPOD) were fed to rumen cannulated goats and rumen samples were collected at the start of the experimental diets (day 0) and on days 4, 6, 8, 12, 18, 24 and 30 post dietary treatments. Feeding DCD and PKCD resulted in significantly higher (P<0.05) DNA copy number of total bacteria, Fibrobacter succinogenes, Ruminococcus flavefeciens, and Ruminococcus albus. Rumen methanogenic archaea was significantly lower (P<0.05) in goats fed PKCD and CPOD and the trend showed a severe reduction on days 4 and 6 post experimental diets. In conclusion, results indicated that feeding DCD and PKC increased the populations of cellulolytic bacteria and decreased the density of methanogenic archaea in the rumen of goats.  相似文献   
5.
The objective was to determine the effect of dietary intake on follicle and oocyte morphology in unstimulated and superovulated ewes. Fifty-four ewes were fed grass meal at 0.5, 1.0 or 2.0 times maintenance energy requirements (M) for 32 days. Oestrous cycles were synchronized using progestagen pessaries and either unstimulated or superovulated with 200 mg pig FSH. The ewes were killed and ovaries were collected either 36 or 12 h before the anticipated LH surge. Serum progesterone concentrations in ewes on day 10 after withdrawal of the pessary were lower in ewes fed 2.0M than in ewes fed 0.5M or 1.0M (P < 0.05). LH pulse frequency tended to be higher in ewes fed 2M than 1M (1.0 +/- 0.3 versus 0.3 +/- 0.2 pulses per 8 h) on day 6 after removal of the pessary but the effect was not significant. In unstimulated ewes, more follicles (>/= 3 mm) were observed when the animals were killed in ewes fed 2.0M (3.5 +/- 0.3) than in ewes fed 0.5M (2.4 +/- 0.3) or 1.0M (2.4 +/- 0.5; P < 0. 05). Fewer follicles were observed in superovulated ewes on 0.5M (7. 5 +/- 1.2) than in ewes on 1.0M (12.0 +/- 0.5) or 2.0M (12.3 +/- 1. 4; P < 0.05). Follicular fluid progesterone concentrations were higher in ewes fed 0.5M compared with those fed 1M or 2M (P < 0.05). Insulin-like growth factor (IGF)-I concentrations were higher in follicular fluid from ewes on 1M compared with either those on 0.5M or 2M (P < 0.05), whereas IGF-II concentrations were lower in follicular fluid from ewes on 2M compared with those on 1M or 0.5M (P < 0.05). Superovulation increased follicular fluid progesterone, oestradiol, IGF-I and IGF-II concentrations (P < 0.01). Concentrations of the 34, 22 and 20 kDa IGF binding proteins were lower in follicles from superovulated ewes compared with unstimulated ewes (P < 0.05). Oocytes from superovulated ewes showed abnormalities such as premature activation of cumulus expansion and vacuolation of the nucleolus and increased frequency of detachment of interchromatin-like granules from the nucleolar remnant. Collectively, these results indicate that both high and low dietary intakes can alter systemic and follicular fluid hormone concentrations. Relative to dietary effects, the effects of superovulation were greater and involved substantial increases in follicular fluid hormone concentrations and abnormal oocyte morphology.  相似文献   
6.
Embryo yield and quality can be decreased following superovulation of cattle on high levels of concentrates. Concentrate type can alter rumen fermentation patterns and so affect energy availability and thus embryo quality. The objectives of this experiment were to examine the effect of 2 levels and 2 types of concentrate on superovulatory response and embryo quality in beef heifers. Beef heifers received grass silage as a basal diet and barley at 3 kg (n = 20) or ad-libitum (n = 19), or citrus/beet pulp at 3 kg (n = 18) or ad-libitum (n = 19) as the source of concentrate supplement. Silage was available ad-libitum for heifers offered 3 kg but was restricted to 1 kg DM/day for heifers on ad-libitum concentrate intake. Both concentrates contained 14% crude protein. After 100 d, heifers were treated with an intravaginal progesterone releasing device (CIDR) for 7 d, and superovulation was initiated 60 h before CIDR withdrawal. Heifers received pFSH (a total of 265 mg NIH-FSH-P1 equivalent) administered over 8 injections at 12 h intervals with the last 2 injections administered at 12 and 24 h after CIDR withdrawal; they were inseminated at 56 and 72 h after CIDR withdrawal without reference to estrus. Heifers were slaughtered 6, 7 or 8 d after the first insemination, and embryos were flushed from the uterus with PBS and were graded morphologically. Statistical analyses were performed using analysis of variance. There was no interaction between level and type of diet, and thus data for the main effects are presented separately. Final live weights at the end of the experiment and carcass weights for heifers offered ad-libitum concentrate (643.8+/-6.9 kg; 354+/-8 kg, respectively) were higher (P<0.01) than those of heifers offered 3 kg concentrate (613.1+/-7.5 kg; 338.4+/-3.2 kg, respectively) while live weights and carcass weights of heifers offered barley (625.6+/-8.1 and 345.4+/-4.1 kg, respectively) or citrus/beet pulp concentrate (631.4+/-7.0 and 348.0+/-3.1 kg, respectively) were not different (P>0.05). Superovulatory responses (number of corpora lutea at slaughter) was greater (P<0.06) when heifers were offered 3 kg (15.5+/-1.6) than when offered ad-libitum concentrates (12.3+/-1.4). However, the superovulatory response for both citrus/beet pulp (14.4+/-1.5) and barley (13.4+/-1.5) diets were not different (P>0.05). Heifers offered 3 kg concentrates produced greater (P<0.05) numbers of transferable embryos (4.8+/-0.7) compared with heifers fed ad-libitum concentrates (2.8+/-0.4). Heifers offered citrus/beet pulp produced greater (P<0.05) numbers of transferable embryos (4.8+/-0.7) than heifers offered barley (2.9+/-0.5). These data indicate that high concentrate intake has a negative effect on embryo yield and quality and that a barley compared with citrus/beet pulp based concentrate has a negative effect on embryo quality following superovulation in beef heifers.  相似文献   
7.
Increasing dietary energy tends to decrease the ovulatory response and produce fewer viable embryos following superovulation of beef cattle. Data in sheep indicate that high energy intake can decrease progesterone concentrations (P4), although effects in cattle are not as clear. The objectives were to evaluate the effects of roughage type and concentrate supplementation on P4 concentrations, follicle growth and subsequent oocyte fertilisation and embryo development in vitro. Forty-two beef heifers were allocated to 3 treatment groups: (i) silage ad libitum plus 6 kg concentrates (silage + conc.; n = 14); (ii) silage ad libitum (silage; n = 14) or (iii) hay ad libitum (hay; n = 14) for 40 days. Oestrus was synchronised using a controlled intravaginal progesterone releasing device (CIDR) for 7 days plus prostaglandin F2 alpha (15 mg luprostiol) administered 2 days before CIDR withdrawal. Ovaries were stimulated with 600 i.u. of follicle stimulating hormone (pFSH) administered in 6 equal doses at 12-h intervals, starting 12 days after CIDR withdrawal. Daily blood samples were collected from 3 days after CIDR insertion until CIDR withdrawal, and for another 3 days prior to pFSH, for P4 determination. Oocytes were recovered postmortem 12 h after the last pFSH injection, matured, fertilised and cultured in vitro. There was no overall effect of diet (P > 0.05) on P4 concentrations. The number of follicles grown in heifers on silage + conc (18.8 +/- 3.3), silage (23.5 +/- 3.4) or hay (18.1 +/- 2.6) were not affected by the dietary treatment (P > 0.05). The percentage of oocytes fertilised from heifers on hay (88%) was higher compared to oocytes from heifers on silage (79%; P < 0.05), but was not different (P > 0.05) compared to the proportion of oocytes from heifers on silage + conc. (86%). The percentage of fertilised oocytes that cleaved was higher from heifers on silage (94%; P < 0.01) compared with oocytes from heifers on hay (82%) or silage + conc. (86%). The proportion of embryos that developed to blastocyst was not different (P > 0.05) between groups of oocytes from heifers on silage + conc. (8%), silage (14%) or hay (15%). Heifers on silage produced numerically more blastocysts (silage: 19 from 14 heifers; silage + conc.: 8 from 14 heifers; hay: 12 from 14 heifers). These results suggest that dietary treatment used prior to oocyte recovery did not significantly influence the developmental competence of the oocytes in vitro.  相似文献   
8.
There is still a lack of information on estrus synchronization in goats. Understanding the estrus synchronization protocols and the subsequent effects is important to improve the efficiency of assisted reproductive technologies (ARTs) and subsequently would improve the breeding procedures. This study will help in determining the most suitable estrus synchronization protocol and understand better the effect on the sexual behaviour and hormonal effects in goats. A total of 127 Boer does were used and divided into three groups with different duration of CIDR insertion intravaginally either for 14 (two groups) or 9 days (one group). Approximately 0.5 ml Estrumate® (PG) was administered intramuscularly to all groups at CIDR removal, and only groups PMSG14 and PMSG9 were administered with 200IU of Pregnant Mare Serum Gonadotropin (PMSG) intramuscularly. Estrus signs were observed at 4 h intervals and blood samples were collected for progesterone and luteinizing hormone determination. The percentage of does in estrus within 24 to 72 h post CIDR removal was significantly higher (P<0.05) in groups with PMSG compared to the group without the PMSG. The numbers of does display estrus signs within 24 to 28 h post CIDR removal were significantly higher (P<0.05) in group shorter period (9 days) compared to groups with 14 days CIDR. The P4 concentrations at 24 hours post CIDR removals and LH concentration was not significantly different (P>0.05) in all groups. The time of the LH peak in the group without the PMSG was significantly delayed (P<0.05) when compared to group 9 days CIDR and administered with PMSG. It is recommended to use the treatment for 9 days CIDR since the estrous cycle can be shortened.  相似文献   
9.
Hybrids in coral reef fishes have traditionally been described based on external features using meristic characters and colouration to identify putative parental contributors. This study utilised molecular genetic techniques to verify hybrid status and identify putative parental species for five hybrid specimens (Labridae: Thalassoma) collected from Holmes Reef in the Coral Sea. Phylogenetic analyses support hybrid origins of the specimens. Mitochondrial COI gene, nuclear S7 (intron 1) and nuclear copy of mitochondrial (NUMT) D-loop region corroborate the identity of T. quinquevittatum as the maternal and T. jansenii as the paternal contributor. Backcrossing to parental species by hybrids and bi-directional gene exchange between the Holmes Reef populations of T. jansenii and T. quinquevittatum was detected, suggesting that hybrids are fertile and able to reproduce successfully. F(1) hybrids display a mixture of the colouration attributes of the two parental species, but subsequent backcrossed individuals were unrecognisable as hybrids and displayed colouration of either parental species. A large numerical imbalance exists between the putative parental species at Holmes Reef, with T. quinquevittatum outnumbering T. jansenii by approximately 25:1. In this case study, hybridization appears to be driven by ecological rather than evolutionary factors.  相似文献   
10.
Testes from nine male Malin × Santa-Ines rams with an average body weight of 43.1 ± 3.53 kg, were used to study the effects of palm kernel cake (PKC) based diet on spermatogenic cells and to assess copper (Cu) levels in liver, testis and plasma in sheep. Animals were divided into three groups and randomly assigned three dietary treatments using restricted randomization of body weight in completely randomized design. The dietary treatments were 60% palm kernel cake plus 40% oil palm frond (PKC), 60% palm kernel cake plus 40% oil palm frond supplemented with 23 mg/kg dry matter of molybdenum as ammonium molybdate [(NH4)6Mo7O24·4H2O] and 600 mg/kg dry matter of sulphate as sodium sulphate [Na2SO4] (PKC-MS) and 60% concentrate of corn-soybean mix  +  40% oil palm frond (Control), the concentrate was mixed in a ratio of 79% corn, 20% soybean meal and 1% standard mineral mix. The results obtained showed that the number of spermatogonia, spermatocytes, spermatids and Leydig cells were not significantly different among the three treatment groups. However, spermatozoa, Sertoli cells and degenerated cells showed significant changes, which, may be probably due to the Cu content in PKC. Liver and testis Cu levels in the rams under PKC diet was found to be significantly higher (P < 0.05) than rams in Control and PKC-MS diets. Plasma Cu levels showed a significant increase (P < 0.05) at the end of the experiment as compared to at the beginning of the experiment for PKC and Control. In conclusion, spermatogenesis is normal in rams fed the diet without PKC and PKC supplemented with Mo and S. However spermatogenesis was altered in the PKC based diet probably due to the toxic effects of Cu and the significant changes in organs and plasma. Thus, Mo and S play a major role in reducing the accumulation of Cu in organs.  相似文献   
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