• Mycobiology
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• 제45권3호
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• pp.172-177
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• 2017

The genus Paxillus is characterized by the difficulty of species identification, which results in reproducibility problems, as well as the need for large quantities of fungal inoculum. In particular, studies of Paxillus ammoniavirescens have reported divergent results in the in vitro growth while little is known of its capacity to degrade organic matter. For all the above, and assuming that this variability could be due to an inappropriate culture media, the aim of this study was to analyse growth in different culture media (MMN, MS, and 1/2 MS) and in the case of MMN in presence/absence of two types of organic matter (fresh litter and senescence litter) to probe the saprophytic ability of P. ammoniavirescens. We also evaluated the effects of pH changes in the culture media. Growth kinetics was assessed by weekly quantification of the area of growth in solid culture media over 5 wk, calculating the growth curves and inflection points of each culture media. In addition, final biomass after 5 wk in the different culture media was calculated. Results showed that best culture media are MS and 1/2 MS. Moreover, an improvement in growth in culture media containing decomposing fall litter was observed, leading to confirm differences in the culture media of this species with others of the same genus. Further, we established that all growth media suffered a significant acidification after fungal growth.

• 한국가금학회지
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• 제30권2호
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• pp.113-118
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• 2003

In this study, broilers were raised up to 6 weeks of age in a single room to determine if different levels of dietary protein or addition of aluminum sulfate[alum, $Al_2$(SO$_4$)$_3$ㆍ14$H_2O$] to the litter affected growth performance, production of ammonia(NH$_3$) and soluble phosphorus(SP) content of the litter.The experimental treatments consisted of six treatments in a 2x3 factorial arrangements: T$_1$＝23% protein ＋ 0.2% alum to litter; T$_2$＝21% protein ＋ 0.2% alum to litter; T$_3$＝19% protein ＋ 0.2% alum to litter; T$_4$＝23% protein ＋ no alum; T$_{5}$＝21% protein ＋ no alum; T$_{6}$＝19% protein ＋ no alum. For broiler performance, there was no effect of alum addition to the litter, but the dietary protein levels significantly affected feed intake from days 22 to 42(P<0.05) and day 0 to 42(P< 0.05), weight gain during all periods(P<0.05 or 0.01), and feed:gain from day 0 to 21(P<0.05) and day 0 to 42(P<0.05). Alum addition to the litter did not affect body weight at 21 and 42 days, but dietary protein levels has a significant effect on it at both 21(P<0.0l) and 42 days(P<0.05). Alum addition only affected ammonia production at weeks 3(P

• Journal of Animal Science and Technology
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• 제63권1호
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• pp.1-15
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• 2021

As a result of intensive breeding, litter size has considerably increased in pig production over the last three decades. This has resulted in an increase in farrowing complications. Prolonged farrowing will shorten the window for suckling colostrum and reduce the chances for high-quality colostrum intake. Studies also agree that increasing litter sizes concomitantly resulted in decreased piglet birth weight and increased within-litter birth weight variations. Birth weight, however, is one of the critical factors affecting the prognosis of colostrum intake, and piglet growth, welfare, and survival. Litters of uneven birth weight distribution will suffer and lead to increased piglet mortality before weaning. The proper management is key to handle the situation. Feeding strategies before farrowing, management routines during parturition (e.g., drying and moving piglets to the udder and cross-fostering) and feeding an energy source to piglets after birth may be beneficial management tools with large litters. Insulin-like growth factor 1 (IGF-1)-driven recovery from energy losses during lactation appears critical for supporting follicle development, the viability of oocytes and embryos, and, eventually, litter uniformity. This paper explores certain management routines for neonatal piglets that can lead to the optimization of their colostrum intake and thereby their survival in large litters. In addition, this paper reviews the evidence concerning nutritional factors, particularly lactation feeding that may reduce the loss of sow body reserves, affecting the growth of the next oocyte generation. In conclusion, decreasing birth weight and compromised immunity are subjects warranting investigation in the search for novel management tools. Furthermore, to increase litter uniformity, more focus should be placed on nutritional factors that affect IGF-1-driven follicle development before ovulation.

• 한국환경과학회지
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• 제24권10호
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• pp.1309-1313
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• 2015

The effects of Houttuynia cordata powder on the growth performance of ducks were investigated. Ninety ducks were assigned into one of three dietary treatments as a completely randomized design for 6 weeks: feeds supplemented with 1% or 2% H. cordata and a control group. No significant difference was observed in feed conversion among the three groups (p > 0.05), but addition of H. cordata had a significantly positive effect (p < 0.05) on initial and final body weight, weight gain, and feed intake of the ducks. Furthermore, the effects of chemical treatment (comprising 50 g and 100 g aluminum chloride [$AlCl_3$] per kilogram litter) on the ammonia ($NH_3$) flux in duck litters were also investigated. Duck litter was treated with $AlCl_3$ at a depth of 8 cm by top-dressing; this resulted in a significant difference on $NH_3$ flux (p < 0.05) during the experimental period (but not at 2 weeks). $NH_3$ flux at 6 weeks were reduced by 25.4% and 37.5% by treatment with 1% and 2% H. cordata, respectively, compared with the control groups. In conclusion, enriching the diets of the ducks with 2% H. cordata and adding 100 g $AlCl_3$ to their litter has beneficial effects on increasing their growth performance and reducing $NH_3$ flux in their environment.

• Journal of Animal Science and Technology
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• 제62권6호
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• pp.777-789
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• 2020

Intense artificial selection has been imposed to Luzhong mutton sheep population in the past years. Improvements on growth and reproductive performance are two breeding goals in the present herd. Although some progresses were phenotypically observed possibly due to inbreeding induced by strong selection in terms of these traits, the genomic evaluation was poorly understood. Therefore, a high-density SNP array was used to characterize the pattern of runs of homozygosity (ROH), estimate inbreeding and inbreeding depressions on early growth performance and litter size based upon ROH, and scan positive selection signatures of recent population. Consequently, a low inbreeding level was observed which had negative effects on litter size, but not on early growth performance. And 160 genes were under selection, of which some were reported to be linked to several traits of sheep including body weight, litter size, carcass and meat quality, milk yield and composition, fiber quality and health, and the top genes were associated with growth (growth hormone [GH]- growth hormone receptor [GHR]- Insulin-like growth factor 1 [IGF1] axis) and litter size (bone morphogenic proteins [BMPs]-associated). The effectiveness of previous breeding measures was highlighted, but purging selection was proposed to alleviate the inbreeding depression on litter size, providing some genomic insights to breeding management of Luzhong mutton sheep.

• Asian-Australasian Journal of Animal Sciences
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• 제27권1호
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• pp.83-92
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• 2014

This experiment was conducted to evaluate the effects of dietary CP levels in gestation under equal lysine content on reproductive performance, blood metabolites and milk composition of gilts. A total of 25 gilts ($F_1$, Yorkshire${\times}$Landrace) were allotted to 4 dietary treatments at breeding in a completely randomized design, and fed 1 of 4 experimental diets containing different CP levels (11%, 13%, 15%, or 17%) at 2.0 kg/d throughout the gestation. Body weight of gilts at 24 h postpartum tended to increase linearly (p = 0.09) as dietary CP level increased. In lactation, backfat thickness, ADFI, litter size and weaning to estrus interval (WEI) did not differ among dietary treatments. There were linear increases in litter and piglet weight at 21 d of lactation (p<0.05) and weight gain of litter (p<0.01) and piglet (p<0.05) throughout the lactation as dietary CP level increased. Plasma urea nitrogen levels of gilts in gestation and at 24 h postpartum were linearly elevated as dietary CP level increased (p<0.05). Free fatty acid (FFA) levels in plasma of gestating gilts increased as dietary CP level increased up to 15%, and then decreased with quadratic effects (15 d, p<0.01; 90 d, p<0.05), and a quadratic trend (70 d, p = 0.06). There were no differences in plasma FFA, glucose levels and milk composition in lactation. These results indicate that increasing dietary CP level under equal lysine content in gestation increases BW of gilts and litter performance but does not affect litter size and milk composition. Feeding over 13% CP diet for gestating gilts could be recommended to improve litter growth.

• The Korean Journal of Ecology
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• 제19권6호
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• pp.563-573
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• 1996

Macroinvertebrate contribution to the leaf litter breakdown of Carpinus cordata was estimated at headwater streams at Mt. Jumbong (38°03'N, 128°25'E) during spring and winter spring by using two types of litter bag. Coarse-mesh bags with 10 g of leaf letter were placed in a 1st-order stream in April (the spring experiment) and December 1995 (the winter-spring experiment). Fine-mesh bags with 5 g of leaf letter were placed in a nearby 3ed-order steam. The breakdown of Carpinus in coarse-mesh bags was rapid, and, in terms of season, leaf litter processed rapidly during spring. daily mass loss rates of leaf litter (-k±1 SE) were highest for coarse-mesh bags in the spring experiment (-0.0429±0.0048), followed by coarse-mesh bags in the winter-spring (-0.0146±0.0014), fine-mesh bags in the spring (-0.0078±0.0004), fine-mesh bags in the winter-spring experiment (-0.0054±0.0005). Macroinvertebrate contribution to the litter breakdown was estimated by the difference of % leaf letter remaining between coarse -mesh bage and fine-mesh bags. Although shredders were more abundant during the winter-spring, their contribution was greater during the spring (50%) than the winter-spring (22∼33%). This result appeared to be due to the change in the chemical composition of leaf letter during processing, and to the seasonal growth patterns of major shredder taxa.

• Journal of Animal Science and Technology
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• 제45권1호
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• pp.33-40
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• 2003

본 연구는 혈장의 insulin-like growth factor (IGF)-I과 IGF-II 농도와 산자수 및 비유성적과의 관계를 구명하고자 착수되었다. 분만주가 비슷한 미경산 및 경산 임신돈 중에서 선발한 총 60두의 순종 Landrace와 Yorkshire 공시돈을 저산자수 (low; <${\mu}$­0.5 SD)와 고산자수 (high; >${\mu}$ + 0.5 SD)-lines로 구분하여 2 (품종) ${\times}$ 2 (line) 요인분석 실험설계 하에 본 실험을 진행하였다. 공시돈은 분만시 모돈당 포유자돈수를 9두로 고정시키고, 3주령 이유시 비유량의 척도로서 총 이유자돈 체중을 측정하였다. 혈액 시료는 임신 90일과 분만 후 15일에 경정맥으로부터 채취하였다. 본 실험기간 중 산자수 및 본 실험기간까지의 평균 산자수는 high-line이 low-line보다 각각 3.7두와 2.4두 많았고 (P< 0.01), 두 품종간 산자수 차이는 없었다. 임신 90일 혈장의 IGF-II 농도는 low-line보다 high-line에서 높았다. 산자수는 임신 90일 IGF-I 농도와 Landrace에서는 부의 상관관계를 나타냈고 (r=－0.46; P<0.05), Yorkshire에서는 부의 상관관계 경향을 나타내어 (r=－0.31; P=0.09) 전체 공시돈에서는 이들 두 변수간 유의적인 부의 상관관계를 보였다 (r=－0.35; P< 0.01). 이유시 모돈당 총 이유자돈 체중은 두 품종간 혹은 두 lines간 차이가 없었다. 이유자돈 체중과 IGF 농도와의 관계는 품종 ${\times}$ 생리적인 생태 조합들간 일정한 경향을 나타내지 않았다. 이상의 결과는 임신 90일 IGF 농도가 임박한 분만시 산자수의 지표가 될 수 있는 가능성을 시사한다.

• 농업과학연구
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• 제44권2호
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• pp.228-234
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• 2017

Feed intake (FI) of sows during lactation is a serious problem because sows require a large amount of energy for high milk production during lactation. Providing a palatable diet is important for lactating sows to cope with the stress of breast-feeding. Palatability can be increased by adding sweeteners to diets. This study was conducted to evaluate the effects of saccharin (sweetener) on growth performance, fecal moisture, and litter performance of lactating sows. Sixteen sows were randomly allotted to one of two dietary treatments in a 27-day trial starting from lactation. The two dietary treatments were supplemented with 0 and 0.2% saccharin (sweetener), respectively. Average daily feed intake (ADFI) was increased (p < 0.05) and back fat loss (BFL) was decreased (p < 0.05) in sows fed saccharin supplementation diets compared with sows fed control diet during lactation. However, sows' body weight loss, body condition score (BCS), fecal score, and the number of piglet survival were not different (p > 0.05) among dietary treatments. The two dietary treatments also had no significantly different effect (p > 0.05) on litter weight and average daily gain (ADG) of piglets. Taken together, saccharin has no significant effect on growth performance of piglets but it can increase FI and reduce BFL of lactating sows.

• Asian-Australasian Journal of Animal Sciences
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• 제21권7호
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• pp.1011-1014
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• 2008

A total of 335 sows at a commercial operation (Hitch Pork Producers Inc, Guymon, OK) was used to determine dietary effects of yeast culture supplementation ($XPC^{TM}$, Diamond V Mills) on litter performance. Sows were grouped by parity (parity 1 to 12). Pigs within a group were then allotted to treatments. Treatments consisted of: CON (no added yeast culture) and YC (12 and 15 g/d XPC during gestation and lactation, respectively). Sows were housed individually and fed their assigned gestation and lactation diets from d 35 of gestation to d 21 of lactation. Sows were fed 2.0 kg/d during gestation and ad libitum during lactation. Voluntary feed intake was measured daily during lactation. At farrowing, numbers of pigs born total and alive were measured. Weights of litters were measured at birth and weaning on d 21 of lactation. Litter weight gain of the YC treatment was 6.9% greater (p<0.01) than that of the CON. However, voluntary feed intake of sows and litter size did not differ between treatments. This study indicates that dietary yeast culture supplementation benefits sow productivity by improving litter weight gain. At present, it is not confirmed if improved litter weight gain was due to milk production, which remains to be investigated.