Farrowing hut design and sow genotype (Camborough-15 vs 25% Meishan) effects on outdoor sow and litter productivity

Performance measures were evaluated for 125 outdoor sows and litters of two crossbred genotypes (Camborough-15 and 25% Meishan) and in two farrowing hut designs (American-style and English-style hut). Contemporary breeding groups of second-parity sows were evaluated in an intensive, outdoor research unit. Sow genotype and hut designs were arranged factorially. Seven complete blocks were evaluated over a 21-wk period. No interactions between environment and genotype were identified for sow and litter productivity. Litters farrowing in the English-style huts weaned 1.5 more (P < .05) piglets per sow (because of a lower preweaning mortality, P = .05) than did litters in the American-style huts. The 25% Meishan weaned 1.7 more (P < .01) pigs per sow than Camborough-15, because of a greater number of piglets born alive. The effects of hut style and genotype were additive and 25% Meishan sows in English-style huts weaned an average (+/- SEM) of 11.1 +/- .83 piglets per sow. The English-style arc hut design may improve outdoor pig production and increase competitiveness of the intensive, outdoor system. The 25% Meishan genotype has potential for increased pigs weaned per litter that must be considered in light of other features of this genotype such as body composition.     

Behavior and performance of lactating sows and piglets reared indoors or outdoors.

Two hundred eighty-seven lactating Newsham sows and their litters were used to determine the effects of intensive indoor (n = 147) and intensive outdoor (n = 140) production systems on sow and litter productivity and behavior. All sows were of contemporary age and fed a completely balanced sorghum-based diet. Behavior data were collected by live observation on 40 sows and litters (20 indoor and 20 outdoor) using a 5-min scan sample over a 4-h period in the afternoon (1400 to 1800). The durations of lying (90.0 vs 72.1 +/- 2.76% of time observed) and drinking (4.42 vs 1.41 +/- 0.6% of time observed) were higher (P < 0.01) among indoor than among outdoor lactating sows. Nursing interval and feeding and sitting behaviors were not different (P > 0.05) between production systems. Piglets spent more (P < 0.05) time walking (10.1 vs 5.2 +/- 1.72% of time observed) and engaged in play activity (5.0 vs 1.7 +/- 1.26% of time observed) when housed outdoors than indoors. Outdoor piglets had more (P < 0.05) nursing behaviors directed toward the sow (27.5 vs 20.3 +/- 2.02% of time observed) but time spent in contact with the sow did not differ between environments (38.8 vs 39.2 +/- 2.78% of time observed). Treatments did not influence (P > 0.05) any of the sow or piglet production parameters. In conclusion, outdoor-kept Newsham sows and their piglets showed a richer behavioral repertoire, but the diverse environments did not influence production parameters.     

Effect of gonadotrophin-releasing hormone on the fertility of sows kept outdoors

A total of 1,231 mixed parity sows from five outdoor units in East Anglia were randomly assigned to one of three treatment groups. Sows in the control group were given no treatment, those in group 1 were injected intramuscularly with 8 microg of the analogue of gonadotrophin-releasing hormone (GnRH), buserelin, within 24 hours after first service and those in group 2 received the same treatment on day 11 or 12 after first service. There was no significant effect of treatment on farrowing rate to first service (85.0 v 85.4 v 84.7 per cent, respectively) or on overall mean (se) total litter size (11.6 [0.2] v 11.9 [0.2] v 11.9 [0.21]), although litter size was significantly increased by both treatments on one unit (11.6 [0.3] v 12.4 [0.3] v 12.8 [0.3]; P<0.05). However, there was a significant increase overall in the numbers of pigs born alive in both treatment groups (10.9 [0.2] v 11.3 [0.1] v 11.4 [0.3]; P<0.05) to sows of parities 0 to 2 only (P<0.05). This increase in numbers born alive is difficult to reconcile with the lack of overall effect on total litter size.     

Biochemical intestinal parameters in pigs reared outdoors and indoors,and in germ-free pigs

Intestinal microbial functions reflect cross-talk between a host and its flora, and external factors may influence these functions. The aim of this investigation was to follow the development of six biochemical microbial-related functions of piglets, raised outdoors (OPs) or indoors (IPs), from birth to slaughter age. The following parameters (microflora-associated characteristic; MAC) were consecutively measured at five different ages: production of short-chain fatty acids (SCFA), conversion of cholesterol to coprostanol and of bilirubin to urobilinogens, inactivation of trypsin, degradation of beta-aspartylglycine and of mucin. Additionally, four parameters (production of SCFA. conversion of cholesterol to coprostanol, inactivation of trypsin, degradation of beta-aspartylglycine) were investigated in faecal samples from germ-free minipigs. The differences in MAC patterns between OPs and IPs were most pronounced at 20 days of age. Differences were found in the total amount of SCFAs, proportions of the acetic, propionic and butyric acids, conversion of bilirubin to urobilinogens, degradation of faecal tryptic activity and degradation of mucin. The values found in the minipigs were within the range of a germ-free animal characteristic (GAC) pattern. Our results show that environmental factors influence the development of some intestinal microbial functions in pigs.     

Immune response of sows and their offspring to pseudorabies virus: serum neutralization response to vaccination and field virus challenge.

One month prior to breeding, sows were vaccinated with an attenuated pseudorabies virus vaccine or challenged with a field strain of pseudorabies virus. A third group of sows were not vaccinated or challenged before breeding. Pigs from these sows were vaccinated at 3, 6, or 12 weeks of age and challenged with virulent virus three weeks later. One pig from each litter served as an unvaccinated, unchallenged control. Serum neutralization titers of these pigs were monitored from birth until 22 weeks of age. Titers of the sows were monitored through breeding, gestation and farrowing. The maximum prefarrowing anti-pseudorabies virus titer in the field virus challenged sows occurred four weeks following challenge. A significant decline in titers occurred at farrowing. Titers rose from one week postfarrowing and then declined. Titers in the field virus infected sows were consistently two to threefold greater than those of the vaccinated sows. The maximum prefarrowing anti-pseudorabies virus titer in the vaccinated sows occurred six weeks following vaccination. The geometric mean titer in these sow's then decreased and increased for two weeks after farrowing. The results in the pigs can be summarized as follows: Pigs from control sows had a greater serological response following field virus challenge than following vaccination with a modified live virus. Pigs from control sows responded serologically to vaccination at 3, 6 and 12 weeks of age. Pigs from control sows which were challenged at 6, 9 and 15 weeks of age had similar antibody responses. Pigs from vaccinated sows had no increase in titer following vaccination at three and six weeks of age. Titers increased when these pigs were vaccinated at 12 weeks of age. There was no significant increase in mean titers of pigs from challenged sows following vaccination at 3, 6 and 12 weeks of age. Vaccinated pigs from control and vaccinated sows had a secondary response following challenge three weeks after vaccination.(ABSTRACT TRUNCATED AT 250 WORDS)     

生长抑素基因疫苗pVAX1-TRX-SS对妊娠母猪及其后代的影响

妊娠后期母猪使用电转化法肌肉注射pVAX1-TRX-SS质粒,观察其对母猪生产性能及其后代的影响。选择30头胎次相近、生理状况相似的母猪,随机分为3组,在妊娠75d时分别用活体基因导入仪注射2mg pVAX1空载体、2mg pVAX1-TRX-SS和4mg pVAX1-TRX-SS。结果表明,2 mg质粒组试验母猪后代初生重比对照组提高9.70%,4mg组比对照组高14.18%,差异都达到极显著水平(P0.01);4mg质粒组的试验母猪后代断奶重分别比对照组和2mg质粒组提高8.16%和4.13%,差异极显著(P0.01);检测血清中生长抑素抗体(SS-Ab)发现,4mg质粒组试验母猪在免疫后40d血清中SS-Ab的P/N极显著高于2 mg质粒组(P0.01),同时显著高于对照组(P0.05),阳性率达60%;对试验母猪及其后代血清激素及相关蛋白检测表明,4mg质粒组试验母猪血清催乳素(PRL)浓度比对照组高120.23%(P0.05),两试验组母猪血清中胰岛素样生长因子1(IGF-1)有比对照组升高趋势,其中4mg组比对照组高18.54%,但差异不显著(P0.05),试验母猪后代血清中的IGF-1未见显著差异(P0.05);4mg质粒组试验母猪血清IGF结合蛋白(IGFBP-3)显著高于对照组和2mg质粒组(P0.05);血清生化指标的测定结果表明,试验组母猪间及其后代间的各项指标都没有显著差异(P0.05),故该质粒对试验母猪及其后代是安全的。本试验表明pVAX1-TRX-SS质粒能引发试验母猪产生免疫反应,提高母猪的生产性能及其后代的断奶重,且对母猪及其后代安全。     

Effects of dietary supplementation of nucleotides from late gestation to lactation on the performance and oxidative stress status of sows and their offspring

Increased metabolic burdens in breeding sows, which are induced by elevated systemic oxidative stress, could increase the need for nucleotides to repair lymphocyte DNA damage; however, de novo synthesis of nucleotides may be insufficient to cover this increased need. This study investigated the effects of dietary nucleotides on milk composition, oxidative stress status, and the reproductive and lactational performance of sows. Forty multiparous sows were assigned to 2 dietary treatments (Control group, and 1 g/kg Nucleotides group) based on a randomized complete block design using their BW at 85 d of gestation as a block. Sows from 2 groups were fed a restricted diet during gestation and ad libitum during lactation. The experiment lasted from 85 d of gestation to 21 d of lactation. The reproductive performance of sows and the growth performance of suckling piglets were measured. Oxidative stress parameters and milk components were also analysed. Data were analyzed using contrasts in the MIXED procedure of SAS. Sows in the Nucleotides group consumed more feed during the first week (P < 0.01) and from 1 to 21 d (P < 0.05) of lactation than those in Control group. Correspondingly, the litter weight gain of piglets showed a tendency to increase from cross-fostering to 9 d (P = 0.09) and from cross-fostering to 20 d (P = 0.10) in the Nucleotides group relative to the Control group. Additionally, the Nucleotides group was higher (P < 0.01) than the Control group in the concentrations of uridine 5''monophosphate, guanosine 5''monophosphate, inosine 5''monophosphate, adenosine 5''monophosphate and total nucleotides in milk. Furthermore, the Nucleotides group was higher (P < 0.01) than the Control group in the serum levels of total antioxidant capacity (P < 0.01) for sows at 109 d of gestation and glutathione peroxidase for weaning piglets, but lower at the levels of thiobarbituric acid-reactive substances (P < 0.05) in serum of weaning piglets. This study indicated that maternal dietary nucleotides could promote piglet growth, probably due to the higher lactational feed intake and higher concentration of nucleotides in the milk of sows, and lower oxidative stress for both sows and piglets.     

Influence of dietary amino acid level on performance,carcass quality and health of organic pigs reared indoors and outdoors

Abstract

The influence of dietary amino acids on performance and carcass quality was studied in 192 organic indoor and outdoor pigs given diets with different amino acid levels (recommended amino acid level, 7% and 14% lower) ad libitum in a two-phase feeding system. During phase 2, daily consumption of lysine, methionine+cystine and threonine was higher for outdoor than indoor pigs independent of amino acid level (p=0.002, 0.004 and 0.006, respectively). The outdoor pigs grew faster during phase 2 than the indoor pigs (p=0.001), although feed conversion ratio did not differ (p=0.358). Dressing percentage was higher for outdoor than for indoor pigs (p=0.011) but lean meat content did not differ (p=0.904). The health status of the pigs was evaluated and showed that the incidence of pigs seropositive to erysipelas was higher outdoors. Ascaris suum was present in both production systems, whereas Eimeria sp. only was found among outdoor pigs. The results indicate a discrepancy between pigs housed in different production systems rather than between pigs directed to different dietary amino acid levels. This suggests that growing/finishing pigs fed ad libitum can compensate for dietary amino acid levels lower than the current Swedish recommendations without affecting production results.     

Safety and efficacy of a classical swine fever subunit vaccine in pregnant sows and their offspring

In the study three groups with five pregnant sows each were used. The animals were vaccinated twice, 2 weeks apart, in different stages of gestation, i.e. +/-4, +/-8 and +/-12 weeks after insemination and then 14 days later, respectively. From each group of sows three litters were randomly selected and vaccinated twice, 4 weeks apart, at 5 and 9, 7 and 11, and 9 and 13 weeks of life, respectively. Blood for serological investigations by virus neutralisation test and ELISA tests (for E(rns) antibodies and for E2 antibodies, separately) was taken before immunisation, at each vaccination and 2 weeks thereafter. Clinical observations shown that no local nor systemic reactions as well as no adverse effect on gestation occurred after vaccinations in any of the sows. Serological tests detected a low level of antibodies after the first vaccination and a typical booster effect after the second one. In piglets no adverse effect of the vaccination on the body weight gain was found. The presence of maternally derived antibodies (MDA) in non-vaccinated control piglets was observed up to the age of 5-13 weeks of life. The most evident immunological reaction was obtained in piglets vaccinated at the age of 5 or 7 weeks of life and revaccinated 4 weeks later. The CSFV-E2 subunit marker vaccine tested proved to be safe for pregnant sows and immunogenic for MDA positive piglets.     

Photoperiod influences the immune status of multiparous pregnant sows and their piglets

Manipulation of photoperiod may provide a noninvasive, easily implemented, effective method to improve immune status and enhance the efficiency of production. The objective of this study was to evaluate the impact of manipulation of photoperiod on endocrine and immune responses of pregnant sows and their offspring. At d 83 of gestation, sows were moved to gestation stalls and kept on a photoperiod of 12 h of light:12 h of dark until d 90, when sows were assigned to a long day (LD; 16 h of light/d) or a short day (SD; 8 h of light/d) treatment. During farrowing and lactation, one-half of the sows remained on their initial photoperiod (LD:LD or SD:SD), whereas one-half were switched to the opposite treatment (LD:SD or SD:LD). Blood samples were collected from sows at d 0, 7, 14, and 21 posttreatment, 24-h postfarrowing, and the end of lactation (approximately d 21 postfarrowing). Piglets were bled at 7 and 21 d of age for immune measures. Relative to sows on LD, sows on SD had greater concanavalin A- (P = 0.003) and lipopolysaccharide- (P = 0.02) induced proliferative responses at d 7 but reduced responses at d 14. Compared with SD, sows on LD had a greater (P < 0.05) percentage of neutrophils and fewer (P < 0.05) lymphocytes at d 7, resulting in a greater (P = 0.05) neutrophil:lymphocyte ratio. Neutrophil phagocytosis was greater at d 21 in sows kept on LD. Cortisol concentrations tended to be greatest (P = 0.10) in sows on SD:SD at 24-h postfarrowing and throughout lactation. At 7 d of age, piglets on LD:SD had greater (P = 0.001) total white blood cells (WBC) and plasma cortisol (P = 0.001) relative to those on the other photoperiod treatments. Plasma immunoglobulin G was less (P = 0.001) in piglets from sows kept on SD:LD compared with the other photoperiod treatments. Piglets from sows kept on LD:LD tended to have lower total WBC (P = 0.08) at 21 d of age. Piglets from sows kept on SD:SD had greater concanavalin A- (P < 0.001) and lipopolysaccharide-induced (P < or = 0.10) proliferation responses and cortisol (P = 0.05). Phagocytosis was greater (P < 0.003) in piglets from sows that were kept on LD:LD. Cortisol (P = 0.02), WBC (P = 0.003), and immunoglobulin G (P = 0.001) were all influenced by gestational photoperiod treatment. These data indicate that photoperiod influences the immune status and endocrine response of piglets from dams that have been kept on a defined photoperiod. We conclude that photoperiod effects on piglets may be programmed in utero and can last throughout lactation.     

The influence of gestational dietary calcium on serum 1, 25-dihydroxycholecalciferol in sows and their pigs

Fifteen multiparous sows (three groups of five) were studied during one gestation-lactation cycle to measure the influence of dietary Ca (.5, .8[control], and 1.1%) on 1,25-dihydroxycholecalciferol (1, 25-(OH)2D3) in serum and colostrum of the sows and serum of their pigs. Concentrations of 1,25-(OH)2D3 and Ca, Mg, P, Cu, and Zn were determined on d 15 and 45 of gestation, at parturition, and at 3 wk postpartum in sow serum and at birth and d 10 and 21 in pig serum. Colostrum was assayed for 1,25-(OH)2D3. Serum 1,25-(OH)2D3 in sows was affected inversely (P less than .05) by dietary Ca within d 15 of gestation and was correlated (r = -.88) with serum Ca during gestation and lactation. Serum Ca was correlated (r = .52) with dietary Ca at d 15 and 45 of gestation and at farrowing. Sow serum Mg was inversely related (r = -.49) to serum Ca during gestation and early lactation. Serum 1,25-(OH)2D3 of the pigs at birth ranged from 38.7 to 44.2 pg/ml was decreased (P less than .05) by 1.1% maternal Ca intake. Sow colostrum 1,25-(OH)2D3 was related (P less than .05) inversely (r = -.40) to sow dietary Ca and directly (r = .90) to sow serum 1,25-(OH)2D3. Serum 1,25-(OH)2D3 of 10- and 21-d-old pigs was inversely related (P less than .05) to their dams' dietary Ca. These results indicate that 1,25-(OH)2D3 production in sows is quickly affected by modest changes in dietary Ca.(ABSTRACT TRUNCATED AT 250 WORDS)     

Social rank of pregnant sows affects their body weight gain and behavior and performance of the offspring

Previous studies on group housing of pregnant sows have mainly focused on reproduction, but we hypothesized that the social rank of pregnant sows housed in groups could also affect birth weight, growth, and behavior of their offspring. Therefore, in the present study, pregnant gilts and sows were housed in 15 different groups (n = 7 to 14 animals per group) from 4 d after AI until 1 wk before the expected farrowing date. All groups were fed by an electronically controlled sow feeding system that registered, on a 24-h basis, the time of first visit, number of feeding and non-feeding visits, and number of times succeeding another sow within 2 s. Only in the first 6 groups (n = 57 animals), agonistic interactions were observed continuously. The percentage of agonistic interactions won was highly correlated (r(s) = 0.90, P < 0.001) with the percentage of displacement success (DS) at the feeding station, which was calculated as: [the number of times succeeding another sow within 2 s/(the number of times succeeded by another sow within 2 s + the number of times succeeding another sow within 2 s)] x 100. This allowed us to classify all sows (n = 166) according to their DS: high-social ranking (HSR) sows had a DS >50% (n = 62) and low-social ranking (LSR) sows a DS <50% (n = 104). Body weights before AI did not differ between HSR and LSR sows, but HSR sows gained more BW during gestation, and lost more BW and back-fat during lactation (P < 0.001). Maternal salivary cortisol concentrations at 2, 7, and 13 wk after AI did not differ between HSR and LSR sows, nor did gestation length, litter size, or percentage of live born piglets. During a novel object (NO) test at 3 wk of age, HSR offspring moved and vocalized more than LSR offspring (P < 0.05). In addition, the latency time to touch the NO was shorter in HSR offspring (P < 0.05), and HSR males spent more time near the NO than LSR males (P < 0.01). At weaning, HSR offspring weighed more than LSR offspring (P < 0.05), and at slaughter HSR offspring had more lean meat than LSR offspring (P < 0.05). Results indicate that the social rank of the sow during gestation affects her own BW gain and loss as well as the growth and behavior of her offspring. Pig breeders that apply group housing for pregnant sows should pay attention to reducing competition around the feeding area, which may reduce aggression among the sows and minimize differences between HSR and LSR sows.     

Effects of dietary resistant starch content on metabolic status,milk composition,and microbial profiling in lactating sows and on offspring performance

In the present study, the effects of dietary resistant starch (RS) content on serum metabolite and hormone concentrations, milk composition, and faecal microbial profiling in lactating sows, as well as on offspring performance was investigated. Sixteen sows were randomly allotted at breeding to two treatments containing low‐ and high‐RS contents from normal and high‐amylose corn varieties, respectively, and each treatment had eight replicates (sows). Individual piglet body weight (BW) and litter size were recorded at birth and weaning. Milk samples were obtained on day 10 after farrowing for composition analysis. On day 2 before weaning, blood and faecal samples were collected to determine serum metabolite and hormone concentrations and faecal microbial populations, respectively. Litter size at birth and weaning were not influenced (p > 0.05) by the sow dietary treatments. Although feeding the RS‐rich diet to sows reduced (p = 0.004) offspring birth BW, there was no difference in piglet BW at weaning (p > 0.05). High‐RS diet increased (p < 0.05) serum triacylglycerol and nonesterified fatty acid concentrations and milk total solid content, and tended (p = 0.09) to increase milk fat content in lactating sows. Feeding the RS‐rich diet to sows increased (p < 0.01) faecal bacterial population diversity. These results indicate that high‐RS diets induce fatty acid mobilization and a greater intestinal bacterial richness in lactating sows, as well as a greater nutrient density in maternal milk, without affecting offspring performance at weaning.     

妊娠后期母猪日粮中添加低聚木糖和益生菌对母猪繁殖性能及哺乳仔猪生长性能的影响

试验旨在研究妊娠后期母猪日粮中添加低聚木糖和益生菌对母猪繁殖性能及哺乳仔猪生长性能的影响。试验采用随机区组试验设计,选取妊娠108 d的母猪(体重及预产期相近,长白×大白)48头,随机分为3个处理,每个处理16个重复,每个重复1头母猪。对照组饲喂基础日粮,试验组分别在基础日粮中添加0.05%XOS(试验1组)和0.05%XOS+0.03%益生菌(试验2组),试验期35 d。结果表明:(1)3个处理母猪哺乳期平均日采食量(ADFI)、产仔总数、活产仔数、合格仔数、初生均重和母猪7 d发情率等几方面差异均不显著(P>0.05)。所有胎次母猪的发情间隔、背膘损失和产程差异均不显著(P>0.05)。但3~6胎次母猪试验1组的发情间隔显著低于对照组(P<0.05),试验2组母猪背膘损失极显著低于对照组(P<0.01);(2)从所有胎次母猪和3~6胎母猪所产仔猪来看,3个试验组仔猪的哺乳期ADG差异不显著(P>0.05)。但从3~6胎以外母猪所产仔猪来看,试验2组的哺乳期ADG比对照组高34.36%(P<0.01),试验1组哺乳期ADG比对照组高21.47%(P<0.05)。(3)3个试验组仔猪断奶成活率没有显著差异(P>0.05)。由此可见,在妊娠后期母猪日粮中单独添加低聚木糖或者同时添加低聚木糖和益生菌对母猪产程和发情间隔没有明显的改善作用,同时添加低聚木糖和益生菌极显著降低3~6胎母猪的背膘损失。仔猪断奶成活率与母猪胎次以及低聚木糖和益生菌的添加水平有关。母源性低聚木糖和益生菌对哺乳仔猪生长性能没有明显促进作用。     

ALA可改善母猪和仔猪体内铁的状况

<正>研究人员已证实,初生仔猪体内储备的铁满足不了其断奶后的营养需要。主要原因是母猪饲料中的铁养分通过胎盘转移给仔猪的效率太低。目前多种含铁化合物已经应用于妊娠和哺乳母猪,以期尝试增加母猪乳汁的铁含量,从而提高仔猪体内铁的水平。可是,这些方法大多达不到理想的效果。因此,为了防止仔猪出现缺铁,通过给出生后数天的     

Different dietary methionine to lysine ratios in the lactation diet:effects on the performance of sows and their offspring and methionine metabolism in lactating sows

Background: Over the last decade, the nutritional requirements of lactating modern genotype sows have increased. The current nutritional recommendations might be unable to meet the needs of increased litter size and milk production, and thus the nutritional requirements need to be re-evaluated. The current study was conducted to investigate the effects of dietary methionine to lysine(Met:Lys) ratios on the performance of and methionine metabolism in lactating sows.Results: During the 1~(st) week of lactation, piglets reared on sows in the 0.37 to 0.57 Met:Lys ratio groups grew faster than those reared on sows in the control group(0.27)(P 0.01). The 0.37-ratio group showed increased levels of GSHPx in plasma during lactation(P 0.01) and decreased concentrations of urea nitrogen in the plasma of sows(P 0.05).Compared with the 0.27-ratio group, the levels of T-AOC and GSH-Px in the plasma and homocysteine in the milk of lactating sows were significantly increased in sows in the 0.47-ratio group(P 0.01). In sows fed a 0.57-ratio diet, the levels of glutathione and taurine in the plasma and milk were improved significantly during lactation. However, the content of TBARS in the blood(P 0.05 at day 7 and P = 0.06 at weaning day) was increased(P 0.01). Moreover, there were linear increases in the levels of homocysteine in the blood and milk of sows during the lactation period(P 0.01)with increased dietary Met:Lys ratios in the lactation diet.Conclusions: The current study indicated that increasing the dietary Met:Lys ratio(0.37～0.57) in the lactation diet had no significant effect on the overall performance of sows or the colostrum and milk composition, but it increased piglet mean BW and piglet ADG during the first week of lactation. Increasing dietary methionine levels had no significant effect on antioxidant function in lactation sows, even though it increased levels of GSH and GSH-Px in the plasma of sows during lactation. However, the content of homocysteine in the plasma and milk increased during lactation due to a high level of dietary methionine.     

Evaluation of 25%, 50%, and 67% Nitrous Oxide with Halothane-Oxygen for General Anesthesia in Horses

Twenty-five percent, 50%, and 67% nitrous oxide was administered to 12 horses anesthetized with halothane and oxygen. Compared to halothane-oxygen alone, there was no significant difference in heart rate, systolic, diastolic, or mean blood pressure values, arterial pH, PaCO2, or plasma bicarbonate values when nitrous oxide was included. A significant linear reduction in PaO2 values could be correlated with N2O:O2 concentrations. The halothane level required to maintain surgical anesthesia was reduced when nitrous oxide was administered, but it was not affected by changing the nitrous oxide concentrations. Nitrous oxide concentrations greater than 25% provide no additional reduction in halothane requirement and may be accompanied by PaO2 values that pose risk to the horse.     

Preventing transmission of sarcoptic mange from sows to their offspring by injection of ivermectin. Effects on swine production

A blind and controlled field study was conducted on a pig farm in Australia to evaluate the activity of 1% ivermectin solution when injected into pregnant sows that were naturally infested with mites. The study was designed to appreciate the tolerance of the product on sows (litter size, litter birth weights, litter weaning weights, pre-weaning mortality) and to show the effects of sarcoptic mange on the growth performances of their offspring. Twenty sows were selected and ranked on Day-10, prior to the start of the study, on the basis of positive mite counts and parity. Sows were randomly allocated into two groups, A and B. On Day-7, they were injected once with product A (1 ml/33 kg; yielding 300 microg ivermectin/kg BW) or product B (placebo), respectively and then moved to the farrowing unit. Mite counts, ear and body lesions were scored and recorded. The average daily weight gain (ADG) was calculated on piglets from birth to Day-45 (ADG(45)) and birth to Day-70 (ADG(70)). Ivermectin was 100% efficient in preventing the transmission of scabies mites and did not have negative effect on the pregnant sows. Growth performances (ADG(45) and ADG(70)) of piglets from treated sows were significantly higher (452 and 541.5 g per day) than that from untreated sows (433.5 and 518.4 g per day) respectively, confirming that sarcoptic mange is detrimental to the production performances of growing pigs.