The influence of premating feeding level and exogenous insulin on the reproductive performance of sows

1991 ◽  
Vol 71 (1) ◽  
pp. 249-251 ◽  
Author(s):  
R. N. Kirkwood ◽  
P. A. Thacker

At weaning (day 0), 120 mixed parity Yorkshire × Landrace sows were allocated in a 2 × 2 factorial arrangement to be fed a 16% crude protein diet at either 1.8 or 3.6 kg d−1 until breeding and to receive either no insulin or insulin (0.75 IU kg−1) on days 1–4, inclusively. There were no significant effects of dietary or insulin treatments on days to rebreeding, farrowing rate or subsequent litter size. Key words: Sow, nutrition, insulin, reproduction

1988 ◽  
Vol 68 (1) ◽  
pp. 69-81 ◽  
Author(s):  
MOHAMED H. FAHMY ◽  
JACQUES J. DUFOUR

Reproductive performance and body weight were studied on 361 ewes, representing Finnsheep (F), DLS (a population of 1/2 Dorset, 1/4 Leicester, 1/4 Suffolk) and seven combinations ranging from 1/8 to 7/8 Finnsheep breeding. Conception rate in yearlings was 61.5% for DLS compared to 89.0% for F with the crosses being intermediate. Conception rate in older ewes was similar in the different genetic groups (avg. 94%). Ovulation rate and litter size at birth of DLS ewes were 1.72 and 1.44 lambs, which was less than half those of F ewes (3.51 and 2.86 lambs, respectively). Both traits increased progressively with an increase in F breeding in crosses and with advances in age. DLS ewes weaned 1.22 lambs compared to 2.03 lambs for F ewes and 1.84 lambs for 4/8 F ewes. The heaviest litters at weaning (31.7 kg) were raised by 4/8 F ewes, followed by 7/8 F (30.8 kg) while those raised by DLS ewes weighed 23.0 kg and F ewes 29.1 kg. Percentage of ova lost per ewe mated averaged 24% and ranged between 18% (DLS and 1/8 F) and 29% (6/8 F). About 3.6% of lambs were born dead and a further 13.8% died before weaning. Preweaning mortality rate was highest in F (22.9%) and lowest in 3/8 F (9.4%). Average kilograms of lambs weaned per ewe exposed was highest in 4/8 F (27.6 kg) followed by F (26.0 kg), whereas that of DLS was the lowest at 18.1 kg. The 4/8 F cross showed 25% heterosis in kg of lambs weaned per ewe exposed and 52.5% increase over DLS. Significant positive linear regressions were calculated for ovulation rate, litter size and preweaning mortality rate on proportion of Finnsheep breeding in crosses. The relation was quadratic for percent ova lost and lamb mortality at weaning. Yearling DLS females weighted 36 kg compared to 44 kg for F yearlings. However, at 5 yr of age DLS ewes weighed 62 kg, 5 kg heavier than F ewes. The heaviest ewes at all ages were the 4/8 F (45 kg at 1 yr, 65 kg at 5 yr). Key words: Reproduction, DLS sheep, Finnsheep, crossbreeding, heterosis, repeatabilities


1991 ◽  
Vol 71 (2) ◽  
pp. 589-591 ◽  
Author(s):  
R. N. Kirkwood ◽  
P. A. Thacker

One hundred gilts and one hundred mixed-parity sows of Yorkshire and Landrace breeding were inseminated with semen with or without an additional 10 μg estradiol-17β. Pregnancy rates of gilts receiving estradiol-supplemented and control semen were 90 and 79%, respectively (P < 0.09). The estradiol supplementation of semen did not improve the pregnancy rates or litter size in sows. Key words: Swine, artificial insemination, estradiol


1991 ◽  
Vol 71 (1) ◽  
pp. 237-239 ◽  
Author(s):  
P. A. Thacker ◽  
A. D. Gooneratne ◽  
R. N. Kirkwood

Pregnancy rates and litter sizes following insemination of sows with fresh-extended and frozen-thawed semen averaged 71 vs. 53% and 10.6 vs. 4.4, respectively, and was not affected by the addition of 12.5 μg relaxin to semen. These results indicate no relaxin mediated effect on either pregnancy rate or litter size when sows are artificially inseminated with relaxin-supplemented semen. Key words: Artificial insemination, relaxin, sows


1992 ◽  
Vol 72 (2) ◽  
pp. 427-429 ◽  
Author(s):  
T. A. Van Lunen ◽  
R. N. Kirkwood ◽  
P. A. Thacker

Seventy-two gilts were fed a 16% crude protein diet supplemented with monensin, salinomycin or not supplemented. There was no effect of treatment on gilt growth between 30 and 100 kg body weight. Monensin-fed gilts tended to have increased, while salinomycin-fed gilts had decreased (P < 0.01), serum growth hormone concentrations. Salinomycin-fed gilts were older and heavier at puberty (P < 0.05). Key words: Monensin, salinomycin, gilts, growth, reproduction


1987 ◽  
Vol 67 (2) ◽  
pp. 405-415 ◽  
Author(s):  
R. N. KIRKWOOD ◽  
S. K. BAIDOO ◽  
F. X. AHERNE ◽  
A. P. SATHER

Two experiments were performed with 78 second parity Lacombe sows to determine the influence of nutrition on reproductive performance. During a lactation of 35 d sows were fed daily either 3 (L) or 6 kg (H) of a diet having 16% crude protein and 12.5 MJ DE kg−1. For exp. 1, six L- and six H-fed sows were given an intravenous injection of gonadotropin releasing hormone (GnRH) at 21 d of lactation and blood was sampled at −30, −10, 0, 10, 20, 30, 45, 90 and 120 min from the time of injection. Prestimulation luteinizing hormone (LH) levels were lower for L-fed than for the H-fed sows (1.34 ± 0.1 vs. 1.93 ± 0.2 ng mL−1' P < 0.02). Peak LH levels achieved after UnKH injection, however, did not differ significantly (5.0 ± 0.6 and 5.8 ± 0.5 ng mL−1 for L and H sows, respectively). In exp. 2, 38 sows were fed the H and 40 fed the L level of feed throughout a 5-wk lactation. As expected, low-level feeding in lactation resulted in a greater body weight and backfat loss (17.4 ± 1.6 vs 41.2 ± 2.3 kg and 3.2 ± 0.4 vs. 6.3 ± 0.1 mm; P < 0.001 for both). Low-level feeding also resulted in an increased incidence of anestrus (15.0 vs. 0.0%) and an extended remating interval (140.7 ± 11.7 vs. 103.4 ± 2.1 h; P < 0.05). At the postweaning estrus, sows were inseminated with either fresh (F) or thawed (T) semen. Treatment groups were thus HF, LF and LT. Pregnancy rate was influenced by both feed level and semen type (90, 72, 69 and 39% for groups HF, HT, LF and LT, respectively). Ovulation rate was unaffected by feed intake (18.7 ± 0.9 vs. 18.2 ± 0.5 for L and H sows, respectively) but embryo survival was influenced by both feed intake and semen type (82.7 ± 2.5, 46.4 ± 9.7, 68.3 ± 9.6 and 53.7 ± 9.8% for groups HF, HT, LF and LT respectively). Eight H and twelve L-fed sows were blood-sampled via indwelling vena caval cannulae at 6-h intervals from weaning until the end of estrus. No treatment effect was noted for plasma levels of LH, growth hormone, estradiol-17β or testosterone during this period. It was concluded that low-plane feeding in lactation and the consequent increased weight and backfat loss reduce reproductive performance of sows. However, the mechanism(s) controlling this effect remain to be fully elucidated. Key words: Sow, lactation, nutrition, estrus


2009 ◽  
Vol 33 (6) ◽  
pp. 1671-1674
Author(s):  
Joana Miller ◽  
Ana Luísa Neves Alvarenga ◽  
Luis David Solis Murgas ◽  
Adriana Cristina da Silva ◽  
Ricardo Sales Araújo ◽  
...  

The aim of this work was to evaluate the efficiency of the intrauterine insemination (IUI) in swine, considering the conception rate, farrowing rate, litter size (alive born pigs). For the IUI, the females had been insemination at 24 and 48 hours after the estrus detection, and the inseminating doses of 500 million, 1 billion, 1.5 billion and 2 billion spermatozoa in 20 mL extender had been used. The procedure of catheter insertion through the cervical canal was successfully performed in 97.9% of the females. The conception rate was 6.3% in the IUI. The farrowing rate in IUI was 87.2% but the farrowing rate was 100% for the sperm concentration of 500 million. Regarding the number of born pigs and alive born pigs observed in females inseminated with IUI, no significant difference was observed (p > 0.05). The concentration of 500 x 10(6) spermatozoa in 20 mL extender in the intrauterine insemination resulted in an optimal reproductive performance.


1984 ◽  
Vol 38 (2) ◽  
pp. 241-247 ◽  
Author(s):  
R. H. King ◽  
I. H. Williams

ABSTRACTA factorial experiment was conducted with 80 first-litter sows and involved two levels of feeding during lactation (ad libitum or 2·0 kg/day), and two levels of feeding between weaning and mating (4·0 or 1·5 kg/day).Average lactation length was 32·2 days. Sows given 2·0 kg/day during lactation lost more backfat (6·3 v. 0·9 mm; P < 0·05) and more live weight (36·8 v. 9·1 kg; P < 0·05) during lactation than sows fed ad libitum and whose average daily food intake was 4·47 kg. Sows receiving 20 kg/day during lactation took longer to return to oestrus after weaning. Within 8 days of weaning more sows fed ad libitum during lactation ovulated (0·90 v. 0·40; x2 = 20·0; P < 0·001) and exhibited oestrus (0·78 v. 0·38; x2 = 12·8; P < 0·001) than sows whose food intake throughout lactation was restricted. Ovulation rate, subsequent litter size and embryonic mortality were not significantly affected by feeding level during lactation.Post-weaning feeding level did not affect the interval between weaning and oestrus. However, sows receiving 4·0 kg/day between weaning and mating had higher ovulation rates (14·8 v. 13·0; P < 0·05) and a greater litter size (10·0 v. 8·8; P < 0·1) at the subsequent farrowing.


1987 ◽  
Vol 67 (3) ◽  
pp. 715-719 ◽  
Author(s):  
R. N. KIRKWOOD ◽  
E. S. LYTHGOE ◽  
F. X. AHERNE

Twenty-four first parity and 48 multiparity crossbred sows (Yorkshire × Landrace) were used in a 2 × 2 factorial design involving high (H) or low (L) lactation feed intakes and the intramuscular injection, or not, of 50 μg of gonadotrophin-releasing hormone (GnRH) at the onset of the first postweaning estrus. All sows were weighed at farrowing and weaning. The H feed intake entailed feeding sows at levels of 10, 13, and 14% of each sow's immediate postfarrowing metabolic weight during weeks 1, 2, and 3–4 of lactation, respectively. Low-fed sows received 50% of the H feed level. The diet contained 12.5 MJ DE kg−1 and 16% crude protein. Between weaning and mating, and following mating, all sows were fed 2.25 kg daily of the lactation diet. After weaning, sows were exposed to a boar twice daily to facilitate estrus detection. GnRH was administered at the onset of standing heat. All sows were slaughtered 25 d after mating at which time the reproductive tracts were removed and examined to determine the number of ovulations and the number of viable embryos. Low-level feeding resulted in an extension of the remating interval (5.9 ± 0.3 vs. 4.5 ± 0.2 d; P < 0.05), an increased incidence of anestrus (16.7 vs. 3.6%; P > 0.1) and a reduction in pregnancy rates (69.7 vs. 81.6%; P > 0.1). Interactions were noted between lactation feeding level and GnRH injection (P < 0.05) and between parity and GnRH injection (P < 0.05) for number of viable embryos. The data obtained suggest that both low level of feeding during lactation and a young age are associated with decreased embryo numbers, but this situation is alleviated by the administration of GnRH. Key words: Sows, feed intake, estrus, GnRH


1985 ◽  
Vol 65 (1) ◽  
pp. 221-229 ◽  
Author(s):  
G. W. DYCK ◽  
J. H. STRAIN ◽  
E. E. SWIERSTRA

Forty-eight Yorkshire (Y) and 48 Yorkshire × Lacombe (YL) primiparous sows were used to evaluate the effect of outside lot and confinement housing from weaning to parturition on reproductive performance over the second to fourth parity. Feed intake of the sows housed in the outside lots was adjusted monthly to provide a similar average gain (54 kg) to that of sows housed in confinement (56 kg). All sows were bred by AI. Sows that did not conceive to mating at the first or second estrus were culled from the experiment. More (P < 0.05) sows housed in the outside lots than in confinement completed the experiment (77.1 vs. 52.1%, respectively). The number of sows that failed to conceive was similar for both treatments but 12 sows housed in confinement and one housed in outside lots were culled due to injury or death. The sows housed in outside lots weaned more (P < 0.01) piglets (8.42 ± 0.23 vs. 7.49 ± 0.25) than those housed in confinement while the number of piglets born (10.20 ± 0.15) and born alive (9.79 ± 0.14) and the weight at birth (1.31 ± 0.02 kg) and weaning (9.45 ± 0.09 kg) were similar. As anticipated, the YL sows farrowed and weaned more and heavier piglets (P < 0.01) than the Y sows. The housing environment did not have a significant effect on the farrowing interval which averaged 159.3 ± 0.6 days. These results indicate that effects of housing conditions from weaning to parturition are limited to the number of sows culled and the number of piglets weaned. Key words: Sows, gestation housing, litter size


Sign in / Sign up

Export Citation Format

Share Document