Aflatoxicosis in rabbits: Effectiveness of Egyptian raw bentonite in prevention or diminution the detrimental effects of naturally aflatoxin contaminated diets

Thirty five females and 15 males of New Zealand White mature rabbits about 6 months of age, were assigned to 1–5 dietary treatments (7 does+3 bucks for each): uncontaminated control diet, naturally aflatoxin contaminated diet without or with 1,2 and 3% bentonite. Rabbit fed with the aflatoxin-diet had a decreased (P<0.01 or 0.05) physical semen characteristics of bucks and a reproductive performance traits of does. The values of conception rate (%), gestation length (days), litter size (n) and litter weights (g) at birth and viability (%) of litters of doe rabbits, fed with the aflatoxin-diet, recorded, respectively: 64.5; 31.0; 4.4; 275.0 and 57.1 versus 85.6; 30.3; 7.9; 508.0; and 100 for those fed with the uncontaminated diet. Addition of bentonite to the aflatoxin contaminated diet improved in general the physical semen characteristics of buck and reproductive performance traits of doe rabbits. The results of the study demonstrate that adding 1% of Egyptian raw bentonite to the naturally aflatoxin contaminated rabbit diets can provide an effective, cheap and safe practical technique for preventing the aflatoxicosis in mature rabbits.     

The effect of level of feeding in early gestation on reproductive success in young rabbit does

An experiment examined the effect of restricted feeding during early gestation on later feed intake and on kindling performance in young rabbit does. Nulliparous rabbit does (n=94) were inseminated at 14.5 weeks of age. During the first 10 days of gestation, does were fed individually either to appetite (AL) or 1.35 times maintenance requirement (R). After 10 days of gestation, all animals were fed to appetite. Does were weighed at insemination and after kindling. Feed intake was recorded during the first 10 days of gestation and weekly, thereafter. The number of does that kindled, number of live and stillborn kits and litter weight was recorded. The experiment ended after kindling. During feed restriction, AL does consumed 70 g/day more on an average than R does (209 and 139+/-4 g for AL and R, respectively; P<0.001). In the first and second week after feed restriction, compensatory feed intake occurred. Restrictive fed does ate more than AL does (+34+/-5 g/day from days 11 to 17 of gestation; P<0.001; +17+/-6g/day from days 18 to 24 of gestation; P<0.05). In the last week of gestation, feed intake of AL and R was comparable (89 and 100+/-5 g, respectively). At kindling, AL does had consumed 8+/-3g/day more feed over the total gestation period than R does (P<0.04). Feeding level during early gestation neither affected the kindling rate (83%), total litter size (7.9+/-0.4) nor the number of does with stillborn kits (10 versus 9 for AL and R, respectively). Regardless of treatment, in the last week of gestation (days 25-32) the number of does with stillbirth was lower and average birth weight was higher (P<0.01) in does eating more than the average daily feed intake compared to does eating below average. Based on the results of this study it was concluded that feed restriction for 10 days in early gestation does not affect kindling performance of young does, but feed intake in the last week of gestation affects kit survival and birth weight.     

Effects of Gestational Maternal Undernutrition on Growth,Carcass Composition and Meat Quality of Rabbit Offspring

An experiment was conducted in order to evaluate the effects of gestational undernutrition of rabbit does on growth, carcass composition and meat quality of the offsprings. Thirty primiparous non lactating rabbit does were artificially inseminated and randomly divided in three treatment groups: Control (C; fed to 100% of maintenance requirements throughout gestation, n = 10), early undernourished (EU; fed to 50% of maintenance requirements during days 7–19 of gestation, n = 10) and late undernourished (LU; fed to 50% of maintenance requirements during days 20-27 of gestation, n = 10). During the 4^th week of the gestation period, LU does significantly lost weight compared to C and EU groups (P<0.05). At kindling, C does produced litters with higher proportions of stillborn kits (P<0.05) while the total litter size (alive and stillborn kits) was not different among groups (10.7, 12.8 and 12.7 kits in C, EU and LU groups, respectively). Kit birth weight tended to be lower in the LU group. During fattening, body weight and feed intake were not different among offsprings of the three experimental groups. Moreover, the maternal undernutrition did not have any impact on carcass composition of the offsprings in terms of carcass parts and internal organs weights as well as meat quality of L. lumborum muscle (pH24, colour, water holding capacity and shear values) at slaughter (70 days of age). Therefore, it can be concluded that the gestational undernutrition of the mother does not have detrimental effects on the productive and quality traits of the offsprings.     

Analyses of factors influencing the birth weight and neonatal growth rate of Cheetah (Acinonyx jubatus) cubs

Birth weight and the neonatal growth rate are reliable indicators of neonatal survival prospects. Data on weight at birth and consecutive weights until 40 days of age were recorded for cheetah cubs in 16 litters. Growth was found to be linear during the first 40 days of life. Weight data were used to evaluate the influence of several factors on birth weight and neonatal growth. The factors used in these analyses were sex, litter identity, litter size, average litter size over the first 40 days, birth weight, parents, gestation length, parity of the dam, and inbreeding. For birth weight and neonatal growth, litter identity was the major explanatory factor (81.8 and 85.3%). For birth weight, a significant influence of gestation length was found (p < 0.05), whereas inbreeding coefficient tended to decrease the birth weight (p = 0.09). Together, gestation length and inbreeding coefficient account for 57.5% of the between‐litter variation for birth weight. Factors with significant influences on neonatal growth are gestation length and parity (p < 0.05). The average litter size over the first 40 days tended to influence neonatal growth (p = 0.07). These three variables together account for 99.9% of the between‐litter variation for neonatal growth during the first 40 days of life. A comparison of neonatal growth between mother‐raised and hand‐raised cubs revealed a lower growth rate in hand‐raised cubs (45 vs. 27 g/day). Zoo Biol 18:129–139, 1999. © 1999 Wiley‐Liss, Inc.     

Effect of turmeric on the viability,ovarian folliculogenesis,fecundity, ovarian hormones and response to luteinizing hormone of rabbits

The present study investigated whether dietary turmeric (Curcuma longa L.) can improve rabbit reproduction, ovarian function, growth, or viability. Female New Zealand White rabbits were either fed a standard diet (n=15) or a diet enriched with 5 g (group E1) or 20 g (group E2) turmeric powder per 100 kg feed mixture (n=16 or 15, respectively). After 295 days, weight gain, conception and kindling rates, pup and mother viability, ovarian macro- and micro-morphometric indices, release of leptin in response to the addition LH, and the release of progesterone, testosterone and leptin by isolated ovarian fragments were analyzed. Dietary turmeric failed to affect ovarian length and weight but did increase the number of primary follicles (E2: 32.5% greater than control group), as well as the diameter of primary (E1: +19.4%, E2: +21.1%), secondary (E2: +41.4%), and tertiary (E1: +97.1%, E2: +205.1%) follicles. Turmeric also increased the number of liveborn (E1: +21.0%) and weaned (E1: +25.0%) pups and decreased the number of stillborn pups (E2: −87.5%) but did not affect weight gain, conception, or kindling rate. Furthermore, dietary turmeric decreased doe mortality during the first reproductive cycle (13.3% in control; 0% in E1; and 6.7% in E2) but not during the second cycle. In vitro, the ovaries of the turmeric-treated rabbits released more progesterone (E1: +85.7%, E2: +90.0%) and less testosterone (E2: −87.0%) and leptin (E2: −29.0%) than the ovaries of control rabbits. Moreover, LH decreased the leptin output of control rabbits but increased that of experimental rabbits. Therefore, it is likely that dietary turmeric improves pup viability and that it could promote rabbit fecundity by either (1) promoting the production of primary ovarian follicles or (2) stimulating the growth of follicles at all stages of folliculogenesis.     

Influence of some sow characteristics on within-litter variation of piglet birth weight

Within-litter variation of piglet birth weight (BW0) is associated with an increased piglet mortality and a high variability in pig weight at weaning and weight or age at slaughter. Data collected in two experimental herds were used to quantify within-litter variability in BW0 and to assess the influence of factors mainly related to the sow. Within 24 h after birth, piglets born alive were individually weighed and stillborn piglets were collectively (first data set) or individually (second data set) weighed. The first data set was restricted to litters with no or only one stillborn piglet (3338 litters). It was used to assess the influence of genetic selection on BW0 variation by comparing litter characteristics before (1994 to 1996) and after (2001 to 2004) the development of hyperprolific sows in this herd. The second data set included all litters (n = 1596) from sows born between 2000 and 2004. For each litter, mean BW0 (mBW0) and its coefficient of variation (CVBW0) were calculated. Then, variance analyses were performed to test the influence of litter size, parity, year of sow birth and season at conception. Prolificacy improvement was associated with an increased CVBW0 in litters from pure Large White (LW) and Landrace × Large White (LR × LW) crossbred sows. The CVBW0 averaged 21% and was significantly influenced by litter size and parity. It increased from 15% to 24% when litter size varied from less than 10 piglets to more than 15 piglets. The proportion of small piglets (i.e. weighing less than 1 kg) increased concomitantly. The CVBW0 was not repeatable from a parity to the following. It was lowest for first and second parities (20%) and thereafter increased progressively. The CVBW0 was positively related to sow's backfat thickness gain during gestation. Taking into account litter size, parity, year of sow birth and season at conception explained 20% of BW0 variation. Thus, major part of heterogeneity is due to other factors, presumably including embryo genotype, on the one hand, and factors that influence embryo and foetus development, such as epigenetic factors, on the other hand.     

Plane of nutrition during gestation affects reproductive performance and retention rate of hyperprolific sows under commercial conditions

Defining a maternal plane of nutrition during gestation is pivotal for improving sow productivity and the cost-effectiveness of feeding. The benefits of increasing the amount of feed during late gestation have been controversial. The objective of this study was to investigate the effects of different planes of nutrition during gestation on reproductive performance of hyperprolific sows and pre-weaning litter performance. One hundred and thirty-five gestating sows were randomly assigned to one of three planes of nutrition throughout parities three and four (P4), as follows: Req – plane designed to meet requirements of prolific sows (2.3 kg per day from day 1 to 21; 1.8 kg per day from day 22 to 75; 2.3 kg per day from day 76 to farrowing); Bump – plane designed as the Req, with increased feed intake during late gestation (3.0 kg per day from day 91 to farrowing); and Maintenance – plane designed to closely meet maintenance requirements of sows (1.8 kg per day from day 1 to farrowing). All treatments were fed the same gestation diet (2.50 MCal NE/kg; 0.67% SID Lysine; 15.17% CP). Sow biometrical parameters at farrowing and at weaning, and litter characteristics were recorded. Also, blood samples were collected for pre- and post-prandial serum glucose and plasma insulin, as well as triglycerides, calcium, and phosphorus analyses. Culling, stratified by cause, and retention rates were recorded in all treatments for each parity. Over two parities, Bump sows had higher weight gain and, at P4, had a higher number of piglets born alive (P < 0.05). Bump sows lost more weight between the end of gestation and weaning over two parities (P < 0.05). Maintenance sows showed reduced body condition score with a higher percentage of piglets removed throughout lactation (due to inappetence and inability to reach the udder) at P4 (P = 0.03). Pre- and post-prandial glucose levels were higher in Bump sows, as well as post-prandial insulin and phosphorus levels at P4 (P < 0.05). Bump sows also showed increased plasma triglycerides compared to the other treatments (P = 0.03). Retention rate was reduced in Maintenance compared to Bump and Req sows at parity 5 (P = 0.02). Taken together, our results indicate that higher feed intake allowance during late gestation may improve the sow’s nutritional status triggering positive results on litter size of hyperprolific sows (e.g., more than 17 total born). However, body condition score must be carefully evaluated to prevent excessive weight gain during successive parities.     

Effect of feeding program during rearing and age at first insemination on performances during subsequent reproduction in young rabbit does

An experiment was performed to study the effect of the feeding program and age at first mating on body growth, feed intake, reproductive performance, and culling of rabbit does over three parities, using 155 does of a strain of New Zealand white rabbits. Three treatments were applied. Ad libitum feeding until first insemination at 14.5 wk (AL-14.5) or 17.5 wk of age (AL-17.5), and restrictive feeding from five wk of age until first insemination at 17.5 wk of age (R-17.5). At first insemination, the BW of AL-14.5 and R-17.5 was similar (3 907 vs. 3 791 +/- 46 g, respectively), whereas AL-17.5 does were heavier (4 390 +/- 46 g, P < 0.001). During reproduction, performance of AL-17.5 was not improved compared to AL-14.5 and R-17.5 does. Al-17.5 does showed a lower feed intake during the first gestation (-25%) and first parity (-10%) than R- 17.5, resulting in weight loss (-6%) during the first gestation and decreased litter weights (-19%) and litter growth (-14%) in the first parity. Extended first mating by three wk (17.5 vs. 14.5 wk) but similar BW at first mating did not affect feed intake and BW development during the first three parities. However, the number of live born kits and weight at first kindling, and litter growth in the first parity were improved in R-17.5 (+23%, +18%, and +14%, respectively). Reproductive performance can be improved by restricted feeding during rearing and extended first insemination to 17.5 wk of age. However, the culling rate was not affected by the rearing strategy.     

Familial Trends in Low Birth Weight

The reproductive performance of sisters and sisters-in-law of 185 women who had delivered “light-for-dates” and “premature expulsion” low birth weight infants was studied. Percentile birth weights were compared taking into account length of gestation, fetal sex, and the height, weight, parity, and smoking habits of the mother. Sisters of women who had delivered light-for-dates babies had lighter babies than the general population, their sisters-in-law, or the sisters of women in the premature expulsion group. These other groups, however, had the expected distribution of percentile birth weights. Data on familial trends in smoking habits and unknown gestation are also presented. The results are consistent with the theory that the mother''s own intrauterine experience affects her reproductive performance but could also be explained by shared family learning experience of as yet unidentified microsocial factors related to pregnancy performance.     

Birth weight from pregnancies dated by ultrasonography in a multicultural British population.

OBJECTIVE--To produce standard curves of birth weight according to gestational age validated by ultrasonography in the British population, with particular reference to the effects of ethnic origin. DESIGN--Retrospective analysis of computerised obstetric database. SETTING--Three large maternity units associated with Nottingham University with over 16,000 deliveries a year. PATIENTS--41,718 women with ultrasound dated singleton pregnancies and delivery between 168 and 300 days'' gestation. MAIN OUTCOME MEASURES--Length of gestation, ethnic origin, parity, maternal height and weight at booking, smoking during pregnancy; the effect of these variables on birth weight. RESULTS--Birth weights from ultrasound dated pregnancies have a higher population mean and show less flattening of the birthweight curve at term than those of pregnancies dated from menstrual history. Significant differences were observed in mean birth weights of babies of mothers of European origin (3357 g), of Afro-Caribbean origin (3173 g), and from the Indian subcontinent (3096 g). There were also significant interethnic differences in length of gestation, parity, maternal height, booking weight, and smoking habit which affected birth weight. The ethnic differences in birth weight were even greater when the effect of smoking was excluded. CONCLUSIONS--Birthweight standards require precise dating of pregnancy and should describe the population from which they were derived. In a heterogeneous maternity population the accurate assessment of an individual baby''s weight needs to take the factors which affect birthweight standards into consideration.     

Maternal Determinants of Birth Weight in Northern Ghana

Objectives

Weight at birth is usually considered as an indicator of the health status of a given society. As a result this study was designed to investigate the association between birth weight and maternal factors such as gestational weight gain, pre—pregnancy BMI and socio—economic status in Northern Ghana.

Methods

The study was a facility-based cross-sectional survey conducted in two districts in the Northern region of Ghana. These districts were purposively sampled to represent a mix of urban, peri—urban and rural population. The current study included 419 mother-infant pairs who delivered at term (37–42 weeks). Mother’s height, pre-pregnancy weight and weight changes were generated from the antenatal records. Questionnaires were administered to establish socio-economic and demographic information of respondents. Maternal factors associated with birth weight were examined using multiple and univariate regressions.

Results

The mothers were generally well nourished before conception (Underweight 3.82%, Normal 57.76%, Overweight 25.06% and Obesity 13.37%) but approximately half of them could not gain adequate weight according to Institute of Medicine recommendations (Low weight gain 49.64%, Adequate weight gain 42.96% and Excessive weight gain 7.40%). Infants whose mothers had excess weight gain were 431g (95% CI 18–444) heavier compared to those whose mothers gained normal weight, while those whose mothers gained less were 479g (95% CI -682– (-276) lighter. Infants of mothers who were overweight and obese before conception were 246g (95% CI 87–405) and 595g (95% CI 375–815) respectively heavier than those of normal mothers, whereas those whose mothers were underweight were 305g (95% CI -565 –(-44) lighter. The mean birth weight observed was 2.98 ± 0.68 kg.

Conclusion

Our findings show that pre-pregnancy body mass index and weight gain during pregnancy influence birth weight. Therefore, emphasis should be placed on counseling and assisting pregnant women to stay within the recommended weight gain ranges.     

Reducing the level of nutrition of twin-bearing ewes during mid to late pregnancy produces leaner prime lambs at slaughter

The Australian prime lamb industry is seeking to improve lean meat yield (LMY) as a means to increasing efficiency and profitability across the whole value chain. The LMY of prime lambs is affected by genetics and on-farm nutrition from birth to slaughter and is the total muscle weight relative to the total carcass weight. Under the production conditions of south eastern Australia, many ewe flocks experience a moderate reduction in nutrition in mid to late pregnancy due to a decrease in pasture availability and quality. Correcting nutritional deficits throughout gestation requires the feeding of supplements. This enables the pregnant ewe to meet condition score (CS) targets at lambing. However, limited resources on farm often mean it is difficult to effectively manage nutritional supplementation of the pregnant ewe flock. The impact of reduced ewe nutrition in mid to late pregnancy on the body composition of finishing lambs and subsequent carcass composition remains unknown. This study investigated the effect of moderately reducing ewe nutrition in mid to late gestation on the body composition of finishing lambs and carcass composition at slaughter on a commercial scale. Multiple born lambs to CS2.5 target ewes were lighter at birth and weaning, had lower feedlot entry and exit weights with lower pre-slaughter and carcass weights compared with CS3.0 and CS3.5 target ewes. These lambs also had significantly lower eye muscle and fat depth when measured by ultrasound prior to slaughter and carcass subcutaneous fat depth measured 110 mm from the spine along the 12th rib (GR 12th) and at the C-site (C-fat). Although carcasses were ~5% lighter, results showed that male progeny born to ewes with reduced nutrition from day 50 gestation to a target CS2.5 at lambing had a higher percentage of lean tissue mass as measured by dual energy X-ray absorptiometry and a lower percentage of fat during finishing and at slaughter, with the multiple born progeny from CS3.0 and CS3.5 target ewes being similar. These data suggest lambs produced from multiple bearing ewes that have had a moderate reduction in nutrition during pregnancy are less mature. This effect was also independent of lamb finishing system. The 5% reduction in carcass weight observed in this study would have commercially relevant consequences for prime lamb producers, despite a small gain in LMY.     

An association analysis of sow parity,live-weight and back-fat depth as indicators of sow productivity

Understanding how critical sow live-weight and back-fat depth during gestation are in ensuring optimum sow productivity is important. The objective of this study was to quantify the association between sow parity, live-weight and back-fat depth during gestation with subsequent sow reproductive performance. Records of 1058 sows and 13 827 piglets from 10 trials on two research farms between the years 2005 and 2015 were analysed. Sows ranged from parity 1 to 6 with the number of sows per parity distributed as follows: 232, 277, 180, 131, 132 and 106, respectively. Variables that were analysed included total born (TB), born alive (BA), piglet birth weight (BtWT), pre-weaning mortality (PWM), piglet wean weight (WnWT), number of piglets weaned (Wn), wean to service interval (WSI), piglets born alive in subsequent farrowing and sow lactation feed intake. Calculated variables included the within-litter CV in birth weight (LtV), pre-weaning growth rate per litter (PWG), total litter gain (TLG), lactation efficiency and litter size reared after cross-fostering. Data were analysed using linear mixed models accounting for covariance among records. Third and fourth parity sows had more (P<0.05) TB, BA and heavier BtWT compared with gilts and parity 6 sow contemporaries. Parities 2 and 3 sows weaned more (P<0.05) piglets than older sows. These piglets had heavier (P<0.05) birth weights than those from gilt litters. LtV and PWM were greater (P<0.01) in litters born to parity 5 sows than those born to younger sows. Sow live-weight and back-fat depth at service, days 25 and 50 of gestation were not associated with TB, BA, BtWT, LtV, PWG, WnWT or lactation efficiency (P>0.05). Heavier sow live-weight throughout gestation was associated with an increase in PWM (P<0.01) and reduced Wn and lactation feed intake (P<0.05). Deeper back-fat in late gestation was associated with fewer (P<0.05) BA but heavier (P<0.05) BtWT, whereas deeper back-fat depth throughout gestation was associated with reduced (P<0.01) lactation feed intake. Sow back-fat depth was not associated with LtV, PWG, TLG, WSI or piglets born alive in subsequent farrowing (P>0.05). In conclusion, this study showed that sow parity, live-weight and back-fat depth can be used as indicators of reproductive performance. In addition, this study also provides validation for future development of a benchmarking tool to monitor and improve the productivity of modern sow herd.     

A pilot study on the prevalence of maternal obesity in selected Greek counties

ObjectiveTo report a pilot prevalence of maternal overweight, obesity and underweight in selected Greek counties.MethodsA total of 441 adult childbearing women were recruited from maternity clinics in 6 Greek counties for this cross-sectional study. Pre-gravid weight status was defined according to the WHO cut-offs and gravid weight status was diagnosed with the Mardones and Rosso weight gain chart.ResultsDuring gestation the majority of the participants were of normal body weight (BW) (34.0%), obesity was apparent in 25.6% of the sample, 23.8% of the participants were underweight, and the remaining 16.6% were overweight. Overall, pregnancy tripled the prevalence of underweight, increased the prevalence of obesity (by 388.0%) and decreased the number of participants in the normal BW category (p ≤ 0.001 for all). The majority of participants classified in each pre-gravid weight-category remained in the same weight category during their gestation. All the pre-gravidly obese women were also obese during pregnancy. Underweight was more prevalent in Kavala (37.5%) and obesity was more frequent in Thessaloniki (30.8%). Women who were overweight prior to conception were highly likely to be overweight/obese during pregnancy (OR: 23.8, CI: 11.1–51.0).ConclusionsThe results indicate a high prevalence of overweight, obesity and underweight among pregnant women in Greece.     

高龄孕妇分娩新生儿出生体重及出院转归的影响因素分析

摘要 目的：探讨高龄孕妇分娩新生儿出生体重及出院转归的影响因素。方法：选择2021年01月到2022年01月与我院就诊的198例产妇作为研究对象,根据孕妇分娩时的年龄分为观察组和对照组,分娩时年龄满35周岁为高龄产妇组（98例）,分娩时年龄为20~34周岁为适龄组（100例）。比较适龄孕妇和高龄孕妇新生儿出生体重情况和新生儿住院时间,对高龄孕妇新生儿体重和新生儿出院转归影响因素进行Logistic单因素分析和多因素分析。结果：与适龄孕妇相比,高龄孕妇新生儿低出生体重儿、巨大儿发生率更高（P<0.05）,新生儿住院时间明显更长（P<0.05）。对高龄孕妇新生儿体重进行单因素分析结果显示,妊娠糖尿病、产检检查、分娩方式、是否使用催产素、分娩时麻醉方式和脐带情况与高龄孕妇新生儿体重无关（P>0.05）,孕妇年龄、孕前BMI、孕期体重增加情况、妊娠高血压、合并其他疾病状况、孕次、产次、羊水情况与高龄孕妇新生儿体重相关（P<0.05）。进行Logistic多因素回归分析结果显示,孕妇年龄、孕前BMI、孕期体重增加情况、孕次、产次、羊水情况是影响高龄孕妇新生儿出生体重的独立危险因素（P<0.05）。对新生儿出院转归情况进行单因素分析结果显示,胎次、开奶时间、喂养方式和有无接受治疗与新生儿出院转归无相关性（P>0.05）,胎龄、出生体重、Apgar评分、出生窒息史、有无伴发疾病与新生儿转归相关（P<0.05）。进行Logistic多因素分析结果显示,胎龄、出生体重、Apgar评分、出生窒息史、有无伴发病是影响新生儿出院转归的独立危险因素（P<0.05）。结论：孕妇年龄、孕前BMI、孕期体重增加情况、孕次、产次、羊水情况是影响高龄孕妇新生儿出生体重的独立危险因素。新生儿出院转归受到胎龄、出生体重、Apgar评分、出生窒息史、有无伴发病影响。     

Effects of dietary enrichment with a marine oil-based n-3 LCPUFA supplement in sows with predicted birth weight phenotypes on birth litter quality and growth performance to weaning

The effects of a marine oil-based n-3 long-chain polyunsaturated fatty acid (mLCPUFA) supplement fed to the sow from weaning, through the rebreeding period, during gestation and until end of lactation on litter characteristics from birth until weaning were studied in sows with known litter birth weight phenotypes. It was hypothesized that low birth weight (LBW) litters would benefit more from mLCPUFA supplementation than high birth weight litters. A total of 163 sows (mean parity=4.9±0.9) were rebred after weaning. Sows were pair-matched by parity and litter average birth weight of the previous three litters. Within pairs, sows were allocated to be fed either standard corn/soyabean meal-based gestation and lactation diets (CON), or the same diets enriched with 0.5% of the mLCPUFA supplement at the expense of corn. Each litter between 9 and 16 total pigs born was classified as LBW or medium/high average birth weight (MHBW) litter and there was a significant correlation (P<0.001) between litter average birth weight of the current and previous litters within sows (r=0.49). Sow serum was harvested at day 113 of gestation for determination of immunoglobulin G (IgG) concentrations. The number of pigs born total and alive were lower (P=0.01) in mLCPUFA than CON sows, whereas the number of stillborn and mummified pigs were similar between treatments. Number of stillborns (trend) and mummies (P<0.01) were higher in LBW than MHBW litters. Tissue weights and brain : tissue weight ratios were similar between treatments, but LBW litters had decreased tissue weights and increased brain : tissue weight ratios compared with MHBW litters. Placental weight was lower (P=0.01) in LBW than MHBW litters, but was not different between treatments. Average and total litter weight at day 1 was similar between treatments. mLCPUFA increased weaning weight (P=0.08) and average daily gain (P<0.05) in MHBW litters, but not in LBW litters. Pre-weaning mortality was similar between treatments, but was higher (P<0.01) in LBW than MHBW litters. IgG concentration in sow serum was similar between treatments and litter birth weight categories. In conclusion, litter birth weight phenotype was repeatable within sows and LBW litters showed the benchmarks of intra-uterine growth retardation (lower placental weight and brain sparing effects). As maternal mLCPUFA supplementation decreased litter size overall, only improved litter growth rate until weaning in MHBW litters, and did not affect pre-weaning mortality, maternal mLCPUFA supplementation was not an effective strategy in our study for mitigating negative effects of a LBW litter phenotype.     

Factors affecting foal birth weight in Thoroughbred horses

Foaling data from 348 Thoroughbred foals born on a commercial stud were analysed to investigate interrelationships among mare age, parity, gestation length, foal sex, placental weight, and foal birth weight. Placental weight was positively correlated with foal birth weight up to a threshold of 6.5 kg; above this, placental weight was not significantly associated with foal birth weight. Placental weight was assessed, including the amniotic membranes and umbilical cord as well as the allantochorion. Using path analysis, parity was positively associated with foal birth weight both directly and through increased placental weights, but age was not directly related to foal birth weight. Over the range of gestation lengths observed, gestation length was not significantly associated with foal birth weight. We conclude that, in populations represented by this study population, either placental weights up to 6.5 kg are rate-limiting for foal birth weight or placental weight increases with foal birth weight up to this threshold. However, further increases in placental weight are not associated with additional increases in foal birth weight. The positive association between parity and foal birth weight is mediated through increased placental weight as well as other pathways. Age is not directly related to foal birth weight and gestation length is not strongly associated with foal birth weight.     

Supplementing sow gestation diets with betaine during summer increases litter size of sows with greater numbers of parities

Conducted during the Australian summer, this experiment evaluated the reproductive performance of sows receiving a diet supplemented with betaine, a potent organic osmolyte and methyl donor. Large White/Landrace/Duroc sows (n=450) ranging in parity from 1 to 7 (parity 2.9 ± 0.10, mean ± SEM), and mated between the 11th of January and 11th February were used. The treatments compared the effects of two gestation diets (standard (Stand) compared to betaine (Bet) supplemented) and two parity groups (parities one and two (P1/2) versus parity three and greater (P3+) on pregnancy outcomes and litter size. The betaine diet was fed from d 3 ± 1 post-mating until farrowing, with betaine content of the diet altered during gestation to ensure a daily intake of 7.6-9.0 g/sow. Liveweight (LW) and LW gain were unaffected by gestation diet; however, on d 1 of lactation P2 backfat (P2) tended (P=0.07) to be greater for standard compared to betaine fed sows (22.5 ± 0.42 compared to 21.5 ± 0.42 mm). P2, LW and LW gain were greater (P<0.05) for P3+ compared to P1/2 sows. Sow farrowing rate (0.79) was unaffected by gestation diet. Total litter size was greater (P<0.05) for Bet3+ (13.6 ± 0.35) sows compared to Stand3+ (12.1 ± 0.34), BetP1/2 (12.1 ± 0.36) and StandP1/2 (12.3 ± 0.38) sows. In conclusion, this is the first study to demonstrate that gestational betaine supplementation during summer increased litter size of sows with greater numbers of parities.     

Assessment of the post partum Reproductive Performance of the Icelandic Dairy Cow During a 3 Year Period

The time of ovulation, artificial insemination (AI), conception and conception rate were studied in 412 Icelandic dairy cows from 2 different areas during a period of 3 years. To assess these parameters the progesterone level was measured in sequential samples of milk and the status of the genital organs evaluated by monthly rectal palpations. The time and number of AI was recorded and the conception rate calculated and compared with the other parameters. Furthermore, the length of the calving interval and gestation period were determined. The effects of year, season, area, age, herd and parity on these parameters were evaluated. The overall mean for the time of first post partum ovulation was 42 days and varied from 29 to 49 days between herds. This is a considerably longer time than recorded for many other breeds of dairy cows. The effects of season, area and herd were significant for the time of first post partum ovulation. The overall time of first post partum AI and conception were 74 days and 97 days, respectively. In spite of late onset of ovarian activity in Icelandic dairy cows, these two pararmeters are comparable to those of other breeds of cattle. The effects of season, parity and herd were significant for these two parameters. The conception rate to first post partum AI was 59% and the number of AI per conception was 1.6. The time of conception correlated closely (r = 0.5) with the time of first post partum AI, but the conception rate to first AI increased and the number of AI per conception decreased with increasing time of first post partum AI. The calving interval was 382 days and the gestation period was 287 days.     

Concentrations of estrone sulfate in peripheral serum of pregnant goats: Relationships with gestation length, fetal number and the occurrence of fetal death in utero

Blood sampling was initiated shortly after breeding and continued weekly through 60 to 72 days post breeding in 20 pregnant and 5 nonpregnant dairy goat does. In does not showing a return to estrus by 72 days, collection of blood was continued at 10- to 14-day intervals until 135 days post breeding. At parturition, the numbers of does delivering one, two, three, four or five kids was four, ten, three, two and one, respectively. Immunoreactive estrone sulfate (ES) was measured in serum by radioimmunoassay (RIA). In nonpregnant does, the mean +/- SD concentration of ES was 0.1 +/- 0.1 nmol/l (n = 36 samples). At 40 to 50 days post breeding, ES concentrations increased dramatically in pregnant does. Statistically, does were classified as pregnant when serum ES increased and remained above 1.1 nmol/l (P < 0.05). Serum ES in pregnant does peaked at 65 to 75 days of gestation, remained at a relative plateau through 120 days and then gradually increased for the remainder of the sampling schedule. There were positive correlations between serum ES and the number of kids born in sampling periods of 50 to 55 days and after 90 days of gestation (P < 0.05). Fetal loss was documented in two does that were not included in the survey data. One doe delivered two normal kids and two mummified fetuses. Time-trend changes in ES were typical of a normal pregnancy. Another doe had a marked decrease in ES (below 0.8 nmol/l) in samples drawn on Days 94 and 108 of gestation while luteal concentrations of progesterone were maintained. This doe delivered one weak, depressed kid, one stillborn kid and a decomposed fetus at the expected time for parturition.