Lysozyme transgenic goats’ milk positively impacts intestinal cytokine expression and morphology

In addition to its well-recognized antimicrobial properties, lysozyme can also modulate the inflammatory response. This ability may be particularly important in the gastrointestinal tract where inappropriate inflammatory reactions can damage the intestinal epithelium, leading to significant health problems. The consumption of milk from transgenic goats producing human lysozyme (hLZ) in their milk therefore has the potential to positively impact intestinal health. In order to investigate the effect of hLZ-containing milk on the inflammatory response, young pigs were fed pasteurized milk from hLZ or non-transgenic control goats and quantitative real-time PCR was performed to assess local expression of TNF-α, IL-8, and TGF-β1 in the small intestine. Histological changes were also investigated, specifically looking at villi width, length, crypt depth, and lamina propria thickness along with cell counts for intraepithelial lymphocytes and goblet cells. Significantly higher expression of anti-inflammatory cytokine TGF-β1 was seen in the ileum of pigs fed pasteurized milk containing hLZ (P = 0.0478), along with an increase in intraepithelial lymphocytes (P = 0.0255), and decrease in lamina propria thickness in the duodenum (P = 0.0001). Based on these results we conclude that consuming pasteurized milk containing hLZ does not induce an inflammatory response and improves the health of the small intestine in pigs.     

Large-scale production of functional human lysozyme in transgenic cloned goats

Human lysozyme (hLZ), an essential protein against many types of microorganisms, has been expressed in transgenic livestock to improve their health status and milk quality. However, the large-scale production of hLZ in transgenic livestock is currently unavailable. Here we describe the generation of transgenic goats, by somatic cell-mediated transgenic cloning, that express large amounts of recombinant human lysozyme (rhLZ) in milk. Specifically, two optimized lysozyme expression cassettes (β-casein/hLZ and β-lactoglobulin/hLZ) were designed and introduced into goat somatic cells by cell transfection. Using transgenic cell colonies, which were screened by 0.8 mg/mL G418, as a nuclear donor, we obtained 10 transgenic cloned goats containing one copy of hLZ hybrid gene. An ELISA assay indicated that the transgenic goats secreted up to 6.2 g/L of rhLZ in their milk during the natural lactation period, which is approximately 5–10 times higher than human milk. The average rhLZ expression levels in β-casein/hLZ and β-lactoglobulin/hLZ transgenic goats were 2.3 g/L and 3.6 g/L, respectively. Therefore, both rhLZ expression cassettes could induce high levels of expression of the rhLZ in goat mammary glands. In addition, the rhLZ purified from goat milk has similar physicochemical properties as the natural human lysozyme, including the molecular mass, N-terminal sequence, lytic activity, and thermal and pH stability. An antibacterial analysis revealed that rhLZ and hLZ were equally effective in two bacterial inhibition experiments using Staphylococcus aureus and Escherichia coli. Taken together, our experiments not only underlined that the large-scale production of biologically active rhLZ in animal mammary gland is realistic, but also demonstrated that rhLZ purified from goat milk will be potentially useful in biopharmaceuticals.     

Consumption of transgenic cows’ milk containing human lactoferrin results in beneficial changes in the gastrointestinal tract and systemic health of young pigs

Lactoferrin is an antimicrobial and immunomodulatory protein that is produced in high quantities in human milk and aids in the gastrointestinal (GI) maturation of infants. Beneficial health effects have been observed when supplementing human and animal diets with lactoferrin. A herd of genetically engineered cattle that secrete recombinant human lactoferrin in their milk (rhLF-milk) have been generated which provide an efficient production system and ideal medium for rhLF consumption. The effects of consumption of rhLF-milk were tested on young pigs as an animal model for the GI tract of children. When comparing rhLF-milk fed pigs to non-transgenic milk fed pigs (control), we observed that rhLF-milk fed pigs had beneficial changes in circulating leukocyte populations. There was a significant decrease in neutrophils (p = 0.0036) and increase in lymphocytes (p = 0.0017), leading to a decreased neutrophil to lymphocyte ratio (NLR) (p = 0.0153), which is an indicator of decreased systemic inflammation. We also observed changes in intestinal villi architecture. In the duodenum, rhLF-milk fed pigs tended to have taller villi (p = 0.0914) with significantly deeper crypts (p < 0.0001). In the ileum, pigs consuming rhLF-milk had villi that were significantly taller (p = 0.0002), with deeper crypts (p < 0.0001), and a thinner lamina propria (p = 0.0056). We observed no differences in cytokine expression between rhLF-milk and control-milk fed pigs, indicating that consumption of rhLF-milk did not change cytokine signaling in the intestines. Overall favorable changes in systemic health and GI villi architecture were observed; indicating that consumption of rhLF-milk has the potential to induce positive changes in the GI tract.     

Evaluating the fitness of human lysozyme transgenic dairy goats: growth and reproductive traits

While there are many reports in the literature describing the attributes of specific applications of transgenic animals for agriculture, there are relatively few studies focusing on the fitness of the transgenic animals themselves. This work was designed to gather information on genetically modified food animals to determine if the presence of a transgene can impact general animal production traits. More specifically, we used a line of transgenic dairy goats expressing human lysozyme in their mammary gland to evaluate the reproductive fitness and growth and development of these animals compared to their non-transgenic counterparts and the impact of consuming a transgenic food product, lysozyme-containing milk. In males, none of the parameters of semen quality, including semen volume and concentration, total sperm per ejaculate, sperm morphology, viability and motility, were significantly different between transgenic bucks and non-transgenic full-sib controls. Likewise, transgenic females of this line did not significantly differ in the reproductive traits of gestation length and litter size compared to their non-transgenic counterparts. To evaluate growth, transgenic and non-transgenic kid goats received colostrum and milk from either transgenic or non-transgenic does from birth until weaning. Neither the presence of the transgene nor the consumption of milk from transgenic animals significantly affected birth weight, weaning weight, overall gain and post-wean gain. These results indicate that the analyzed reproductive and growth traits were not regularly or substantially impacted by the presence or expression of the transgene. The evaluation of these general parameters is an important aspect of defining the safety of applying transgenic technology to animal agriculture.     

Consumption of pasteurized human lysozyme transgenic goats’ milk alters serum metabolite profile in young pigs

Nutrition, bacterial composition of the gastrointestinal tract, and general health status can all influence the metabolic profile of an organism. We previously demonstrated that feeding pasteurized transgenic goats’ milk expressing human lysozyme (hLZ) can positively impact intestinal morphology and modulate intestinal microbiota composition in young pigs. The objective of this study was to further examine the effect of consuming hLZ-containing milk on young pigs by profiling serum metabolites. Pigs were placed into two groups and fed a diet of solid food and either control (non-transgenic) goats’ milk or milk from hLZ-transgenic goats for 6 weeks. Serum samples were collected at the end of the feeding period and global metabolite profiling was performed. For a total of 225 metabolites (160 known, 65 unknown) semi-quantitative data was obtained. Levels of 18 known and 4 unknown metabolites differed significantly between the two groups with the direction of change in 13 of the 18 known metabolites being almost entirely congruent with improved health status, particularly in terms of the gastrointestinal tract health and immune response, with the effects of the other five being neutral or unknown. These results further support our hypothesis that consumption of hLZ-containing milk is beneficial to health.     

Protein profile and alpha-lactalbumin concentration in the milk of standard and transgenic goats expressing recombinant human butyrylcholinesterase

The expression of recombinant proteins of pharmaceutical interest in the milk of transgenic farm animals can result in phenotypes exhibiting compromised lactation performance, as a result of the extraordinary demand placed on the mammary gland. In this study, we investigated differences in the protein composition of milk from control and transgenic goats expressing recombinant human butyrylcholinesterase. In Experiment 1, the milk was characterized by gel electrophoresis and liquid chromatography/mass spectrometry in order to identify protein bands that were uniquely visible in the transgenic milk and/or at differing band densities compared with controls. Differences in protein content were additionally evaluated by computer assisted band densitometry. Proteins identified in the transgenic milk only included serum proteins (i.e. complement component 3b, ceruloplasmin), a cytoskeleton protein (i.e. actin) and a stress-induced protein (94 kDA glucose-regulated protein). Proteins exhibiting evident differences in band density between the transgenic and control groups included immunoglobulins, serum albumin, β-lactoglobulin and α-lactalbumin. These results were found to be indicative of compromised epithelial tight junctions, premature mammary cell death, and protein synthesis stress resulting from transgene expression. In Experiment 2, the concentration of α-lactalbumin was determined using the IDRing^® assay and was found to be significantly reduced on day 1 of lactation in transgenic goats (4.33 ± 0.97 vs. 2.24 ± 0.25 mg/ml, P < 0.01), but was not different from non-transgenic controls by day 30 (0.99 ± 0.46 vs. 0.90 ± 0.11 mg/ml, P > 0.05). We concluded that a decreased/delayed expression of the α-lactalbumin gene may be the cause for the delayed start of milk production observed in this herd of transgenic goats.     

Impact of lactation stage on milk composition and blood biochemical and hematological parameters of dairy Baladi goats

The objective of this study was to elucidate the impact of lactation stage on milk composition, hematological and biochemical parameters of dairy Baladi goats under Egyptian conditions. Forty-eight Baladi goats (32.8 ± 2.9 kg of BW) were enrolled in the current study. The lactation period has been divided into three stages; early (DIM less than 80 days), Mid (DIM 80–140 days), and Late (DIM over 140 days). Baladi goats had decreased daily-MY at a rate of 18.4% and 31.9% at mid and late stages of lactation, compared with early stage, respectively (p = 0.001). Furthermore, lactose% decreased significantly with progress of lactation (p = 0.017). Total solids%, however, decreased significantly at early stage of lactation in comparison with mid and late stages (p = 0.022). On the contrary, no significant differences were found in protein, fat and SNF percentages at different stages of lactation (p = 0.836, 0.625 and 0.281, respectively). Serum glucose and total protein were significantly reduced at late stage of lactation in comparison with early and mid stages (p = 0.001 and 0.001, respectively). On the contrary, no significant differences were found for erythrocytes count, hemoglobin, serum cholesterol, catalase and triiodothyronine at different stages of lactation. There were high and positive correlations between daily-MY and serum total protein (r = 0.87, P < 0.01) and triiodothyronine (r = 0.41, P < 0.01). However, negative estimates were reported between daily-MY and triglycerides (r = ?0.55, P < 0.01) and cholesterol (r = ?0.33, P < 0.05). Our results indicate that dairy Baladi goats produce milk with relatively stable protein, fat and solid not fat (SNF) contents at the different stages of lactation, encouraging the continuous utilization of their milk in processing. Also, dairy Baladi goats seem able to maintain the most vital biochemical parameters.     

Consumption of milk from transgenic goats expressing human lysozyme in the mammary gland results in the modulation of intestinal microflora

Lysozyme is a key antimicrobial component of human milk that has several health-promoting functions including the development of a healthy intestinal tract. However, levels of lysozyme in the milk of dairy animals are negligible. We have generated transgenic dairy goats that express human lysozyme (HLZ) in their milk in an attempt to deliver the benefits of human milk in a continual fashion. To test the feasibility of this transgenic approach to achieve a biological impact at the level of the intestine, feeding trials were conducted in two animal models. Pasteurized milk from HLZ transgenic animals was fed to both kid goats (ruminant model) and young pigs (human model), and the numbers of total coliforms and Escherichia coli present in the small intestine were determined. Data from this proof-of-principle study demonstrate that milk from transgenic animals was capable of modulating the bacterial population of the gut in both animal models. Pigs that consumed pasteurized milk from HLZ transgenic goats had fewer numbers of coliforms and E. coli in their intestine than did those receiving milk from non-transgenic control animals. The opposite effect was seen in goats. Milk from these transgenic animals not only represent one of the first transgenic food products with the potential of benefiting human health, but are also a unique model to study the development and role of intestinal microflora on health, well-being and resistance to disease.     

Consuming Transgenic Goats' Milk Containing the Antimicrobial Protein Lysozyme Helps Resolve Diarrhea in Young Pigs

Childhood diarrhea is a significant problem in many developing countries and E. coli is a main causative agent of diarrhea in young children. Lysozyme is an antimicrobial protein highly expressed in human milk, but not ruminant milk, and is thought to help protect breastfeeding children against diarrheal diseases. We hypothesized that consumption of milk from transgenic goats which produce human lysozyme (hLZ-milk) in their milk would accelerate recovery from bacterial-induced diarrhea. Young pigs were used as a model for children and infected with enterotoxigenic E. coli. Once clinical signs of diarrhea developed, pigs were fed hLZ-milk or non-transgenic control goat milk three times a day for two days. Clinical observations and complete blood counts (CBC) were performed. Animals were euthanized and samples collected to assess differences in histology, cytokine expression and bacterial translocation into the mesenteric lymph node. Pigs consuming hLZ-milk recovered from clinical signs of infection faster than pigs consuming control milk, with significantly improved fecal consistency (p = 0.0190) and activity level (p = 0.0350). The CBC analysis showed circulating monocytes (p = 0.0413), neutrophils (p = 0.0219), and lymphocytes (p = 0.0222) returned faster to pre-infection proportions in hLZ-milk fed pigs, while control-fed pigs had significantly higher hematocrit (p = 0.027), indicating continuing dehydration. In the ileum, pigs fed hLZ-milk had significantly lower expression of pro-inflammatory cytokine IL-8 (p = 0.0271), longer intestinal villi (p<0.0001), deeper crypts (p = 0.0053), and a thinner lamina propria (p = 0.0004). These data demonstrate that consumption of hLZ-milk helped pigs recover from infection faster, making hLZ-milk an effective treatment of E. coli-induced diarrhea.     

Effect of the rearing system on financial returns from Murciano-Granadina breed goats

In dairy goats, the kid rearing system can have critical importance in financial returns. Commonly used criteria for the choice of rearing system are not always clear due to the high number of factors involved. The aim of this study was to quantify all those factors to facilitate decision making. So, the effect of two different kid rearing systems, mixed rearing system (MRS) and artificial rearing system (ARS), on milk yield, milk composition and somatic cell count (SCC), milk yield loss at weaning for MRS, kid growth and costs of the different traits on the financial returns in Murciano-Granadina breed goats was studied. Twenty-four goats per group were used. In the MRS, goats reared only one kid, which had free access to goat milk 24 h a day and were weaned at week 6 of lactation, whereas kids in the ARS were separated from their mothers at kidding, colostrum and artificially reared. In both systems, dams were machine-milked once a day throughout lactation and the records took place weekly. Potential milk yield was estimated according to the oxytocin method up to week 12 of lactation, and was similar for both rearing systems, although a 12.3% drop in potential milk yield at weaning was observed for MRS. During the first 6 weeks of lactation, marketable milk was lower for dams in MRS compared to those in ARS (72.1 v. 113.0 l), but similar for the rest of the experiment (101.5 v. 99.4 l, respectively). Marketable milk composition and SCC throughout the 12 weeks of lactation were unaffected by the rearing system. Artificial rearing system entailed an increment in production cost of 22.2€ per kid compared to the rearing by MRS. A similar economic return per goat and kid was obtained from ARS and MRS in this experiment, although, due to one herd’s prolificacy of 1.8, the actual results would be 16.2€ per goat in favour of MRS. The real interest of this experiment may be the possibility of extrapolation to different flocks with diverse levels of milk production, prolificacy and prices and costs for incomes and outputs, to estimate the production system that increases returns. In conclusion, the results showed an increase in the cost of €22.2 per kid bred in the ARS, compared to the MRS, and a final return of 16.2€ per goat in favour of the mixed system.     

Piglet growth before and after weaning in relation to a qualitative estimate of solid (creep) feed intake during lactation: A pilot study*

Abstract

The experimental objectives were to verify whether a qualitative measure of creep feed consumption using a dye was related to performance, and associate this with teat order. Indigo carmine (5 g/kg) was added to a starter diet between days 12 and 31 (weaning) of lactation. On days 19, 23, 27 and 31, faeces from each piglet were assessed for colouration. Each piglet was categorized as a ‘good’, ‘moderate’ or ‘small/non’ eater of feed. There were no differences in pre-weaning growth rate between categories. Piglets classed as ‘good’ or ‘moderate’ eaters in lactation grew fastest (p = 0.009) in the first three days after weaning, but between days 4 and 7, the highest growth rate occurred in ‘moderate’ eaters. ‘Small/non' eaters grew slower (p < 0.01) between weaning and 28 days after weaning. Piglets drinking milk from anterior teats were heavier at weaning (p < 0.001) and for the first 14 days after weaning (p = 0.104) compared to piglets sucking posterior teats. Data from this study demonstrated that creep feed intake of piglets could qualitatively be assessed using indigo carmine, and that this categorization was related to performance in the immediate post-weaning period.     

Spironolactone reduces aortic stiffness via blood pressure-dependent effects of canrenoate

Spironolactone is thought to improve aortic stiffness via blood pressure (BP) independent (antifibrotic) effects, but the exact mechanism is unknown. We used metabolomics and hemodynamic measures to reveal the underlying actions of spironolactone in people with a hypertensive response to exercise (HRE). Baseline and follow-up serum samples from 115 participants randomized to 3 months spironolactone (25 mg/day) or placebo were analysed using liquid chromatography/mass spectrometry and nuclear magnetic resonance spectroscopy. Hemodynamic measures recorded at baseline and follow-up included aortic pulse wave velocity (stiffness) and 24 h ambulatory BP. Aortic stiffness was significantly reduced by spironolactone compared with placebo (?0.18 ± 0.17 vs 0.30 ± 0.16 m/s; p < 0.05), but this was no longer significant after adjustment for the change in daytime systolic BP (p = 0.132). Further, the change in aortic stiffness was correlated with the change in daytime and 24 h systolic BP (p < 0.05). Metabolomics detected 42 features that were candidate downstream metabolites of spironolactone (no endogenous metabolites), although none were correlated with changes in aortic stiffness (p > 0.05 for all). However, the spironolactone metabolite canrenoate was associated with the change in daytime systolic BP (r = ?0.355, p = 0.017) and 24 h pulse pressure (r = ?0.332, p = 0.026). This remained highly significant on multiple regression and was independent of age, body mass index and sex. Canrenoate appears to be an active metabolite with BP-dependent effects on the attenuation of aortic stiffness in people with HRE. This finding, together with the lack of change in endogenous metabolites, suggests that the antifibrotic effects of spironolactone could be BP-dependent.     

Generation of transgenic goats by pronuclear microinjection: a retrospective analysis of a commercial operation (1995–2012)

Production of transgenic founder goats involves introducing and stably integrating an engineered piece of DNA into the genome of the animal. At LFB USA, the ultimate use of these transgenic goats is for the production of recombinant human protein therapeutics in the milk of these dairy animals. The transgene or construct typically links a milk protein specific promoter sequence, the coding sequence for the gene of interest, and the necessary downstream regulatory sequences thereby directing expression of the recombinant protein in the milk during the lactation period. Over the time period indicated (1995–2012), pronuclear microinjection was used in a number of programs to insert transgenes into 18,120, 1- or 2- cell stage fertilized embryos. These embryos were transferred into 4180 synchronized recipient females with 1934 (47%) recipients becoming pregnant, 2594 offspring generated, and a 109 (4.2%) of those offspring determined to be transgenic. Even with new and improving genome editing tools now available, pronuclear microinjection is still the predominant and proven technology used in this commercial setting supporting regulatory filings and market authorizations when producing founder transgenic animals with large transgenes (> 10 kb) such as those necessary for directing monoclonal antibody production in milk.     

Characterisation of caecal microbial diversity of lactating does and their offspring given diets with different neutral detergent soluble to insoluble fibre ratios

The effect of neutral detergent soluble fibre (NDSF) to neutral detergent fibre (NDF) dietary ratio (0.29, LR and 0.43, HR) on the caecal ecosystem of lactating does and their offspring was studied. From the 17th day of lactation, each diet was given to four does, allowing for free access to their litters. Does were sampled at 17 and 28 days of lactation, and also two pups per litter at 17 (milk-fed only), 28 (milk and solid fed) and 49 days of age. DGGE was used to study bacterial caecal biodiversity, and total bacterial concentration and relative proportions of Ruminococcus albus and Butyrivibrio fibrisolvens were quantified by real time PCR. In does, diet did not affect (P > 0.10) diversity indexes, total bacterial concentration or relative abundance of B. fibrisolvens, but at 28 days of lactation the proportion of R. albus was higher with LR (interaction Diet × Time, P = 0.037). Caecal communities of pups of 17 days were grouped by litter, but the influence of the mother was reduced at 28 days with solid feed intake, and at 49 days rabbits clustered by diet. Caecal biodiversity increased from 17 to 28 days, and was reduced at 49 days (Shannon index of 3.60, 3.71 and 3.57, respectively; P = 0.049). Total bacterial concentration and relative abundance of R. albus and B. fibrisolvens increased with solid feed intake from 17 to 28 days (P < 0.01), remaining unaffected thereafter. Access of pups to solid feed from 17 days of age modulates the development and composition of the caecal microbiota at weaning.     

Effect of water restriction on lactation performance of Aardi goats under heat stress conditions

This study was conducted to evaluate the effect of water restriction on lactation performance in Aardi goats. The experiment divided into 3 periods each of 6 days; control, water restriction and rehydration. Nine lactating Aardi goats in early lactation were divided into two groups. One group (n = 5) received 50% and the other group (n = 4) received 25% restriction of drinking water relative to their consumed water during control period. Both groups exhibited a fall in dry matter intake with almost a similar rate. Live weight loss during water restriction was similar in both groups (8 and 6% in 50 and 25% water restriction, respectively). Milk production was also reduced by 20 and 18% with 50 and 25% water restriction, respectively. Milk fat percentage was lower in goats that received 25% restriction while it was maintained unchanged in the 50% restriction group. Total solids of milk tended to decrease in goats with 25% water restriction without any change in milk osmolality. Whereas, milk osmolality increased without any alterations in total solids of milk with 50% water restriction. It could be concluded that lactating Aardi goats possess a high capacity of withstanding water restriction when it was coupled with higher environmental temperature.     

Large-scale neurochemical metabolomics analysis identifies multiple compounds associated with methamphetamine exposure

Methamphetamine (MA) is an illegal stimulant drug of abuse with serious negative health consequences. The neurochemical effects of MA have been partially characterized, with a traditional focus on classical neurotransmitter systems. However, these directions have not yet led to novel drug treatments for MA abuse or toxicity. As an alternative approach, we describe here the first application of metabolomics to investigate the neurochemical consequences of MA exposure in the rodent brain. We examined single exposures at 3 mg/kg and repeated exposures at 3 mg/kg over 5 days in eight common inbred mouse strains. Brain tissue samples were assayed using high-throughput gas and liquid chromatography mass spectrometry, yielding quantitative data on >300 unique metabolites. Association testing and false discovery rate control yielded several metabolome-wide significant associations with acute MA exposure, including compounds such as lactate (p = 4.4 × 10^?5, q = 0.013), tryptophan (p = 7.0 × 10^?4, q = 0.035) and 2-hydroxyglutarate (p = 1.1 × 10^?4, q = 0.022). Secondary analyses of MA-induced increase in locomotor activity showed associations with energy metabolites such as succinate (p = 3.8 × 10^?7). Associations specific to repeated (5 day) MA exposure included phosphocholine (p = 4.0 × 10^?4, q = 0.087) and ergothioneine (p = 3.0 × 10^?4, q = 0.087). Our data appear to confirm and extend existing models of MA action in the brain, whereby an initial increase in energy metabolism, coupled with an increase in behavioral locomotion, gives way to disruption of mitochondria and phospholipid pathways and increased endogenous antioxidant response. Our study demonstrates the power of comprehensive MS-based metabolomics to identify drug-induced changes to brain metabolism and to develop neurochemical models of drug effects.     

Correlation between lactoferrin and beneficial microbiota in breast milk and infant’s feces

Lactoferrin (LF) is a natural component of human milk with antimicrobial, immunostimulatory and immunomodulatory properties. Several in vitro studies suggest that LF could promote an environment in the gut of neonates that favors colonization with beneficial bacteria. However, clinical studies on the correlation between the concentration of LF in breast milk and feces of infants and the gut microbiota in infants are lacking. In our study we analyzed the content of LF and the microbiota of breast milk and feces of infants of 48 mother–infant pairs (34 full-term and 14 pre-term infants) at birth and 30 days after delivery. In the term group, a significant decrease of mean LF concentration between colostrum (7.0 ± 5.1 mg/ml) and mature milk (2.3 ± 0.4 mg/ml) was observed. In pre-term group, breast milk LF levels were similar to those observed in full-term group. Fecal LF concentration of healthy infants was extremely high both in term and pre-term infants, higher than the amount reported in healthy children and adults. In term infants mean fecal LF levels significantly increased from birth (994 ± 1,828 μg/ml) to 1 month of age (3,052 ± 4,323 μg/ml). The amount of LF in the feces of 30 day-old term infants was significantly associated with maternal mature milk LF concentration (p = 0.030) confirming that breast milk represents the main source of LF found in the gut of infants. A linear positive correlation between colostrum and mature milk LF concentration was observed (p = 0.008) indicating that milk LF levels reflect individual characteristics. In pre-term infants higher mean concentrations of fecal LF at birth (1,631 ± 2,206 μg/ml) and 30 days after delivery (7,633 ± 9,960 μg/ml) were observed in comparison to full-term infants. The amount of fecal bifidobacteria and lactobacilli resulted associated with the concentration of fecal LF 3 days after delivery (p = 0.017 and p = 0.026, respectively). These results suggest that high levels of fecal LF in neonates, particularly in the first days of life, could represent an important factor in the initiation, development and/or composition of the neonatal gut microbiota. Since early host–microbe interaction is a crucial component of healthy immune and metabolic programming, high levels of fecal LF in neonates may beneficially contribute to the immunologic maturation and well-being of the newborn, especially in pre-term infants.     

Effect of artificial vs. natural rearing on milk yield,kid growth and cost in Payoya autochthonous dairy goats

Seventy full lactations of Payoya dairy goats were used to study the effect of two different kid-rearing systems, natural or artificial, on milk yield, composition, hygiene-sanitary quality, kid growth and rearing cost. Two animal groups were established, one with goats under natural rearing (NS) and the other under artificial rearing (AR). In the NS group, the kids had free access to goat milk 18–20 h a day and were suckled up to 5 weeks of age and then the dams were milked twice daily. Dams in the AR were separated from their kids at 48 h post-partum; then, kids were reared artificially, and the dams were milked twice daily. The number of animals used in each type of rearing system was 35 (23 goats giving birth to twins and 12 goats giving birth to a single kid). Each week during suckling phase the volume of milk produced was measured, and individual samples were taken. From 5th week and until 210 days lactation, test-day yields recorded at intervals of 30 ± 3 days were obtained. The chemical composition of the milk, the bacteriology, and the somatic cell count was analyzed. The kids of both sexes were assigned to two groups, natural suckling (NS, n = 58) and ad libitum artificial rearing (AR, n = 58). Within each treatment, two groups of kids were formed depending on prolificacy: first group with kids from single birth (n = 12) and the second with twin kids (n = 46). Birth weight and weight every week upto the 4th week of life were recorded. During the 5 weeks of lactation the total milk yield per goat was higher for the NS group (140.2 L vs. 95.4 L; P < 0.001), although the total amount of marketable milk was greater for the AR group, with a difference of some 21 L (P < 0.05). Throughout the entire lactation the milk yield was higher in the group of natural rearing (total yield of 508 L vs. 400 L; P < 0.05). Although a significant effect of prolificacy was found during suckling phase (P < 0.001), during 30 weeks of lactation this factor did not affect milk yield (P > 0.05). For the milk composition and hygiene-sanitary quality there were no effects on the type of rearing system or the type of birth (P > 0.05). No significant effect was observed either for the feeding system or the sex or the prolificacy on the live weight of the kids at 28 days and the postnatal growth rate from birth to 28 days (P > 0.05). Natural rearing system had higher cost per kid comparing with artificial rearing system (€18.63/kid vs. €14.70/kid, respectively). However, when comparing total incomes during a full lactation, goats with natural rearing system had a higher income because of increment of total milk production (€29.95/kid).     

The iFat1 transgene permits conditional endogenous n-3 PUFA enrichment both in vitro and in vivo

Fat-1 transgenic mice, which endogenously convert n-6 PUFA to n-3 PUFA, are a useful tool in health research; however with this model timing of n-3 PUFA enrichment cannot be directly controlled. To add such capability, the novel Cre-recombinase inducible fat-1 (iFat1) transgenic mouse has been developed. The aim of this study was to characterize the utility of the iFat1 transgene as a model of Cre-inducible endogenous n-3 PUFA enrichment. Functionality of the iFat1 transgene was screened both in vitro and in vivo. In the presence of Cre, the iFat1 transgene resulted in a balancing (p < 0.01) of the n-6/n-3 PUFA ratio within phospholipids in the human embryonic kidney 293T cell line. For in vivo analysis, iFat1 transgenic mice were crossed with the R26-Cre-ER^T2 (Tam-Cre) mouse line, a tamoxifen inducible Cre-expression model. Tam-Cre/iFat1 double hybrids were transiently treated with tamoxifen at 6–7 weeks, then terminated 3 weeks later. Tamoxifen treated mice had increased (p < 0.05) tissue n-3 PUFA and ≥two-fold reduction (p < 0.05) in the n-6/n-3 PUFA ratio of liver, kidney and muscle phospholipids relative to vehicle treated controls. Collectively these findings suggest that the iFat1 transgenic mouse may be a promising tool to help elucidate the temporal effects through which n-3 PUFA impacts health related outcomes.