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1.
OBJECTIVE--To examine the effects of maternal diet during lactation and the use of formula feeds on the development of atopic eczema in infants at risk. DESIGN--Mothers who planned to breast feed exclusively were randomly allocated to either a restricted diet (avoiding milk and other dairy products, eggs, fish, peanuts, and soybeans) or a diet without restrictions. Mothers who did not plan to breast feed were randomly allocated to using one of three formula feeds. SETTING--Child health centre in Canada. SUBJECTS--97 Mothers who chose to breast feed and 124 mothers who did not. INTERVENTIONS--Restricted diet for 49 mothers who breast fed. Casein hydrolysate formula, soy milk formula, or cows'' milk formula for infants not breast fed. MAIN OUTCOME MEASURE--Development of eczema in babies. RESULTS--Infants were followed up over 18 months and examined for eczema. Eczema was less common and milder in babies who were breast fed and whose mothers were on a restricted diet (11/49 (22%) v 21/48 (48%)). In infants fed casein hydrolysate, soy milk, or cows'' milk 9/43 (21%), 26/41 (63%), and 28/40 (70%), respectively, developed atopic eczema. CONCLUSIONS--In families with a history of atopic disease [corrected] mothers who breast feed should avoid common allergenic foods during lactation. If they choose not to breast feed a hydrolysate formula should be used.  相似文献   

2.
The effect of changing feeds on individual feed intake and feeding and dominance ranks in groups of African catfish Clarias gariepinus was investigated. Following feeding on a commercial feed groups (n = 3) of six African catfish were either fed fish meal (FM42) or maize gluten (MG35) based feeds for 5 days before being switched to the other feed for 5 days. Energy intake was significantly lower on FM42 than on MG35, dry matter intake and protein intake were significantly lower on FM42 than on commercial feed and this occurred whether FM42 was fed first or second. There were no significant differences between intake of MG35 and commercial feed. Thus, the action of changing the feed on its own did not affect feed intake since the decrease was shown to be feed‐specific to FM42. Six types of agonistic behaviours were identified and used to assign dominance rank. There were no correlations between dominance and feeding ranks. This was due to non‐linear hierarchies with one dominant fish in each group. Feeding ranks were more stable when feeding MG35 than FM42. Feeding rank stability (Kendall's coefficient of concordance) was significant in five out of six groups fed MG35 (compared with three out of six fed FM42). Feeding rank stability was higher in five out of the six groups when they were fed MG35 than when the same group was fed FM42. The experiment provided evidence that the introduction of a novel feed can, but does not necessarily, alter feed intake and that feed can influence the stability of feeding ranks.  相似文献   

3.
Pinealectomized and control groups of Single Comb White Leghorn pullets were housed in individual laying cages within an experimental room maintained at a temperature of 22 ± 2°C. Hourly feed intake data were collected on the birds subjected to single 3-h changes in the duration of light or dark periods at either auroral (lights-on) or vespertine (lights-off) time of a 14L:10D lighting cycle. Feed intake reached an acrophase at either the 12th or 13th hour of the light period then declined until the onset of darkness. Vespertine changes in the light cycle were more effective in shifting the intake acrophase than the auroral changes. This observation was consistent irrespective of the direction of the change. When the laying hens were subjected to a 26-h lighting rhythm, the strength of cyclic light as a zeitgeber for feed intake rhythm was again demonstrated. The feed intake rhythm developed a 26-h duration with an acrophase consistently 22–23 hours post-vespertine. Pinealectomy did not effect the ability of hens to adjust to new lighting regimens.  相似文献   

4.
From in-vitro studies of breast and cow''s milk preparations, and of the faeces from breast-fed and bottle-fed infants, a number of factors seemed likely to influence the production and maintenance of a lactobacillary flora and low pH in the faeces of newborn infants. These were mainly attributable to the nature of the feed. It is suggested that responsible factors in breast milk include its high lactose, low protein, low phosphate content, together with its poor buffering capacity. Importance is also attached to the fact that breast milk seems to provide a fluid feed of small bulk and low residue, and that its use is unlikely to include periods of starvation. Cow''s milk, on the other hand, which has a low lactose, high protein, high phosphate content, and a high buffering capacity, is a relatively bulky, high-residue feed. Feeding regimens which employ it are likely to include periods of starvation.  相似文献   

5.
Biofilm formation on reverse osmosis (RO) systems represents a drawback in the application of this technology by different industries, including oil refineries. In RO systems the feed water maybe a source of microbial contamination and thus contributes for the formation of biofilm and consequent biofouling. In this study the planktonic culturable bacterial community was characterized from a feed water of a RO system and their capacities were evaluated to form biofilm in vitro. Bacterial motility and biofilm control were also analysed using phages. As results, diverse Protobacteria, Actinobacteria and Bacteroidetes were identified. Alphaproteobacteria was the predominant group and Brevundimonas, Pseudomonas and Mycobacterium the most abundant genera. Among the 30 isolates, 11 showed at least one type of motility and 11 were classified as good biofilm formers. Additionally, the influence of non-specific bacteriophage in the bacterial biofilms formed in vitro was investigated by action of phages enzymes or phage infection. The vB_AspP-UFV1 (Podoviridae) interfered in biofilm formation of most tested bacteria and may represent a good alternative in biofilm control. These findings provide important information about the bacterial community from the feed water of a RO system that may be used for the development of strategies for biofilm prevention and control in such systems.  相似文献   

6.
In ethanol fermentations inhibition of the microorganism by ethanol limits the amount of substrate in the feed that can be converted. In a process high feed concentrations are desirable to minimize the flows. Such high feed concentrations can be realized in integrated processes in which ethanol is recovered from the fermentation broth as it is formed. In this study ethanol recovery by pervaporation was coupled to glucose fermentations by baker's yeast. Pervaporation was carried out with commercial silicone based hollow-fibre membrane modules with relatively high fluxes. Three different types of process configurations with pervaporation were investigated. Two of these configurations also included cell retention by microfiltration, in order to optimize the productivity. In the systems with pervaporation a feed containing 360 kg/m3 glucose could be converted almost completely. This feed concentration is a factor three higher than in a process without ethanol recovery. The productivity was 14 kg/m3 h in a system with pervaporation only, and could be increased to 43 kg/m3 h in the system with all recycle by microfiltration. The kinetic data suggest that accumulation of inhibitory compounds occurs in the integrated system. The integrated process was relatively easy in operation.  相似文献   

7.
Feed is usually the costliest input in lactating cow's farms. Therefore, the developing of methods for a better adjustment of feed intake to cow's energetic needs in order to improve efficiency is desired. The aim of this study was to improve feed efficiency of low-efficient (LE) cows through a moderate increase in diet forage-to-concentrate ratio. We studied the effects of replacing 8.2% corn grains in a control low-fiber (LF) diet that contained 17.5% forage neutral detergent fiber (NDF) with 7.5% wheat straw + 0.7% soybean meal for a high-fiber (HF) diet that contained 23.4% forage NDF. Based on efficiency data of individual cows from the Agricultural Research Organization's herd measured in our previous study, 15 pairs of pre-classified LE multiparous mid-lactating Israeli Holstein dairy cows were selected, each pair with similar performance, intake, and efficiency data; each member of a pair was then adapted for 2 weeks to one or the other dietary treatment. Traits examined during the 5 weeks of the experiment were DM intake (DMI), eating behavior, milk production, in vivo digestibility, and estimation of feed efficiency [energy-corrected milk (ECM)/DMI and energy balance]. Cows fed the HF diet showed slower eating rate, smaller visit and meal sizes, longer daily eating time, higher visit frequency, and longer meal duration, compared to those fed the LF diet. The DMI of cows fed the HF diet was 9.1% lower, their DM digestibility decreased from 65.7 to 62.2%, and their ECM yield was 7.0% lower than in cows fed the LF diet. Feed efficiency, measured as net energy captured/digestible energy intake, improved in the cows fed the HF vs. LF diet while feed efficiency measured as ECM/DMI remained similar. Our results thus show the potential of improving feed efficiency for milk production in LE cows by increasing the forage-to-concentrate ratio.  相似文献   

8.
南方锦天牛Acalolepta speciosa是近年在油茶Camellia oleifera上新出现的一种蛀干害虫。为摸清南方锦天牛对不同寄主的取食和产卵选择行为,采用林间调查和室内观测的方法,记录害虫在不同寄主上的取食面积和产卵量。林间调查发现,广宁红花油茶C. semiserrat上未发现南方锦天牛危害状;南方锦天牛在距离地面72.0 cm以下、胸径大于1.0 cm以上的高州油茶C. gauchowensis、普通油茶C. oleifera树干上产卵,在叶片上不产卵;成虫产卵量与高州油茶、普通油茶寄主种类、树干胸径大小无相关性。室内试验表明,南方锦天牛成虫在木荷Schima superb、橡树Quercus palustris、马尾松Pinus massoniana和葡萄Vitis vinifera上既不取食也不产卵;取食山茶科Theaceae的山茶Camellia japonica和油茶的树皮和叶片,取食选择性无显著差异;成虫在油茶树干上产卵,在山茶树干上不产卵,产卵选择性无显著差异。  相似文献   

9.
This study aimed to characterize the intestinal yeasts in weaning piglets and to establish their possible relationships with main bacterial groups. German Landrace piglets were weaned (WP, n=32) at 28 days of age or kept with the dams until day 39 without creep feed (UP, n=32). The experiment was performed at an experimental and a commercial farm (CF). Faeces were collected from the piglets, sows and pen floors on days 28, 33 and 39 for isolation of DNA and cultivation for enumeration of yeasts, enterobacteria, enterococci and lactobacilli. Fragments of the D1 domain of 26S rRNA gene were amplified and separated by denaturing gradient gel electrophoresis (DGGE). No yeasts could be cultured from water and feed samples. No or only low numbers of yeasts were detected among all UP. In WP at CF, yeasts correlated with lactobacilli (r=0.456; P=0.009) and enterobacteria (r=-0.407; P=0.021). Kazachstania slooffiae dominated among the cultured yeasts. It was the only yeast species detected by PCR-DGGE. Yeasts, especially K. slooffiae, established in the porcine gastrointestinal tract after consumption of grain-based feed and may interrelate with the intestinal microbiota. The study provides data indicating importance of K. slooffiae for the development of balanced porcine gut microbiota.  相似文献   

10.
Tylenchorhynchus dubius was observed to feed on ''Toronto'' creeping bentgrass and ''Merion'' Kentucky bluegrass, and was a key participant in reducing the vegetative growth of both grass species. The severity of foliar and root macrosymptoms incited by T. dubius to ''Toronto'' bentgrass was greater on plants grown at 16 C than on plants maintained at 21, 27 and 32 C. These parasitized plants exhibited a suppression of secondary stolon formation, shortened internodes and premature inflorescence initiation. Initial inoculum densities of 500 and 1000 nematodes/test pot produced similar pathogenic effects on the host. Feeding was primarily on root hairs and epidermal cells immediately behind the meristematic region. No necrotic lesions or other diagnostic symptoms were visible at the feeding sites. Nematodes were not observed inside the roots.  相似文献   

11.
With the high cost of feed for animal production, genetic selection for animals that metabolize feed more efficiently could result in substantial cost savings for cattle producers. The purpose of this study was to identify DNA markers predictive for differences among cattle for traits associated with feed efficiency. Crossbred steers were fed a high‐corn diet for 140 days and average daily feed intake (ADFI), average daily gain (ADG), and residual feed intake (RFI) phenotypes were obtained. A region on chromosome 14 was previously associated with RFI in this population of animals. To develop markers with the highest utility for predicting an animal's genetic potential for RFI, we genotyped additional markers within this chromosomal region. These polymorphisms were genotyped on the same animals (n = 1066) and tested for association with ADFI, ADG and RFI. Six markers within this region were associated with RFI ( 0.05). After conservative correction for multiple testing, one marker at 25.09 Mb remained significant (= 0.02) and is responsible for 3.6% of the RFI phenotypic variation in this population of animals. Several of these markers were also significant for ADG, although none were significant after correction. Marker alleles with positive effects on ADG corresponded to lower RFI, suggesting an effect increasing growth without increasing feed intake. All markers were also assessed for their effects on meat quality and carcass traits. All of the markers associated with RFI were associated with adjusted fat thickness (AFT, 0.009) and three were also associated with hot carcass weight (HCW, 0.003). Marker alleles associated with lower RFI were also associated with reduced AFT, and if they were associated for HCW, the effect was an increase in weight. These markers may be useful as prediction tools for animals that utilize feed more efficiently; however, validation with additional populations of cattle is required.  相似文献   

12.
Most cows'' milk based formulae for infant feeding present a greater acid load to the infant than breast milk. To determine the effect of this difference the acid base state of 180 healthy term infants was measured on the sixth day of life and related to the type of feed. Those infants fed on cows'' milk formula (SMA) had a mean pH of 7-34 +/- 0-05 and a base deficit of 8-8 +/- 3-1, while those fed on breast milk had a mean pH of 7-38 +/- 0-05 and a base deficit of 5-6 +/- 3-1. The difference between the two groups of infants was significant for both these measurements. Metabolic acidosis was defined as a base deficit greater than 10 mmol/l. Seventy-four per cent of the 34 infants who were acidotic at six days were bottle-fed. There was a significant correlation between the pH of the feed and the degree of acidosis in the infant as measured by the base deficit. The findings suggest that when breast milk is not available a pH-adjusted milk formula would be desirable for preventing and treating neonatal metabolic acidosis.  相似文献   

13.
Abstract

The identification of introduced and native predators is important for many conservation studies within New Zealand. Carcasses of Hutton's shearwaters were collected over three field seasons, and where predation was probable, the bodies were autopsied. Paired bites identified stoats as the principal predator of Hutton's shearwater, but also revealed that a feral cat was present within the colony. Stoats killed their prey with a bite to the back of the neck or head, and commenced feeding on the neck or head. Despite the limited number of cat‐killed birds, cats appeared to feed on Hutton's shearwaters differently from stoats, starting on the breast muscles. Harriers and kea left sign that allowed birds killed or scavenged by these native birds to be distinguished from those killed by stoats or cats.  相似文献   

14.
Distillers' grains are a co-product of ethanol production. In China, only a small portion of distillers' grains have been used to feed the livestock because the amount was so huge. Nowadays, it has been reported that the distillers' grains have the potential for fuel ethanol production because they are composed of lignocelluloses and residual starch. In order to effectively convert distillers' grains to fuel ethanol and other valuable production, sodium hydroxide pretreatment, step-by-step enzymatic hydrolysis, and simultaneous saccharification and fermentation (SSF) were investigated. The residual starch was first recycled from wet distillers' grains (WDG) with glucoamylase to obtain glucose-rich liquid. The total sugar concentration was 21.3 g/L, and 111.9% theoretical starch was hydrolyzed. Then the removed-starch dry distillers' grains (RDDG) were pretreated with NaOH under optimal conditions and the pretreated dry distillers' grains (PDDG) were used for xylanase hydrolysis. The xylose concentration was 19.4 g/L and 68.6% theoretical xylose was hydrolyzed. The cellulose-enriched dry distillers' grains (CDDG) obtained from xylanase hydrolysis were used in SSF for ethanol production. The ethanol concentration was 42.1 g/L and the ethanol productivity was 28.7 g/100 g CDDG. After the experiment, approximately 80.6% of the fermentable sugars in WDG was converted to ethanol.  相似文献   

15.
16.
We investigated the effect of 50% nutrient restriction during the last 6 weeks ofgestation on twin-pregnant ewes' plasma glucose, non-esterified fatty acid, β-hydroxybutyrate, insulin, IGF-1 and leptin concentrations and the effects on lamb birth weight and ewes' lactation performance. Plasma metabolite and hormone concentrations in restricted ewes suggest that maternal tissues were being mobilised. Despite the ewes' adaptations their lambs weighed significantly less at birth. Furthermore, colostrum and milk yields were markedly reduced up until the latest measurement at 3 weeks post partum despite ad libitum access to feed. Reduced milk yields coincided with reduced plasma IGF-1 concentration pre partum in nutrient restricted ewes indicating, that mammary gland development may have been compromised. The present data suggest that leptin is not involved in the regulation of early lactation changes in feed intake and energy balance. It is concluded that severely reduced nutrient availability in late gestation affects fetal growth in utero and has a prolonged negative effect on lactation performance.  相似文献   

17.

Background

Genomic selection can be implemented by a multi-step procedure, which requires a response variable and a statistical method. For pure-bred pigs, it was hypothesised that deregressed estimated breeding values (EBV) with the parent average removed as the response variable generate higher reliabilities of genomic breeding values than EBV, and that the normal, thick-tailed and mixture-distribution models yield similar reliabilities.

Methods

Reliabilities of genomic breeding values were estimated with EBV and deregressed EBV as response variables and under the three statistical methods, genomic BLUP, Bayesian Lasso and MIXTURE. The methods were examined by splitting data into a reference data set of 1375 genotyped animals that were performance tested before October 2008, and 536 genotyped validation animals that were performance tested after October 2008. The traits examined were daily gain and feed conversion ratio.

Results

Using deregressed EBV as the response variable yielded 18 to 39% higher reliabilities of the genomic breeding values than using EBV as the response variable. For daily gain, the increase in reliability due to deregression was significant and approximately 35%, whereas for feed conversion ratio it ranged between 18 and 39% and was significant only when MIXTURE was used. Genomic BLUP, Bayesian Lasso and MIXTURE had similar reliabilities.

Conclusions

Deregressed EBV is the preferred response variable, whereas the choice of statistical method is less critical for pure-bred pigs. The increase of 18 to 39% in reliability is worthwhile, since the reliabilities of the genomic breeding values directly affect the returns from genomic selection.  相似文献   

18.
D. Wang  F. Cai  S. Yan  Z. Zhao  B. Sun 《Animal genetics》2017,48(6):686-690
Residual feed intake (RFI) is a measure of feed efficiency. Pigs with low RFI have reduced feed costs without compromising their growth. For marker‐assisted selection, it is helpful to identify genes or genetic markers associated with RFI in animals with improved feed efficiency at an early age. Using Illumina's PorcineSNP60 BeadChip, we performed a pilot genome‐wide association study of 217 Junmu No. 1 white male pigs phenotyped for RFI. Two‐step and one‐step methods were used separately to identify associated SNPs. Both methods obtained similar results. Twelve SNPs were identified as significantly associated with RFI at a Bonferroni adjusted P‐level < 9.7 × 10?7, and 204 were found to have suggestive (moderately significant) association with RFI at P < 5 × 10?5. NMBR, KCTD16, ASGR1, PRKCQ, PITRM1, TIAM1 and RND3 were identified as candidate genes for RFI.  相似文献   

19.
Male broiler chicks (n = 120) were fed diets containing 0, 5, 10 or 15% dried distillers' grains with solubles (DDGS) from the 12th day up to the end of fattening (day 35). During this period feed intake, weight gain and excreta quality (pH, DM) were tested. A digestibility trial was carried out on four birds from each group on the last five days of the experiment to determine the digestibility of organic matter and CP of the different diets. The protein digestibility was evaluated using three different methods; uric acid correction, α-amino-N and amino acid-N. There were no significant effects of increased DDGS levels on feed intake, weight gain, excreta quality or digestibility of CP and organic matter. However, feed conversion showed a tendency to decline at the highest DDGS level (15%). Digestibility of DDGS protein was estimated to be 77%. There was no significant difference between uric acid and α-amino-N method, but both methods had a significantly lower CP digestibility than amino acid-N. The present results indicate that DDGS can be used as a protein source in diets for fattening broilers up to 10–15%.  相似文献   

20.
A prospective study was designed to investigate the weaning practices of 50 primiparous mothers whose babies were born between September 1976 and March 1978. The question whether the age of weaning influenced growth from birth to 6 months was also considered. The mothers and babies were seen in hospital and then at a follow-up clinic at 1, 2, 3, and 6 months. Details were taken of feeding practices, and measurements made of the babies'' weight, length, and subscapular and triceps skinfold thicknesses. Seventeen infants who were breastfed received their first solid food at a mean age of 13.8 weeks, compared with 8.3 weeks for the 33 bottle-fed infants. Most (38) mothers weaned because they though their babies were hungry (crying after a feed or demanding more frequent feeds, or both). The age of weaning did not influence weight gain, growth in length, or change in skinfold thicknesses. The results suggest that the "4-month rule" for weaning is unrealistic. The decision to wean should be based more on the mother''s interpretation of her baby''s needs than on age alone.  相似文献   

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