The composition of serval (Felis serval) milk during mid-lactation

Milk was obtained from three captive servals. The average nutrient content was 158.3+/-44.4 g protein; 152.6+/-62.3 g fat; and 68.7+/-31.4 g lactose per kg milk. The protein fraction respectively consisted of 117.7+/-44.8 g caseins per kg milk and of 40.6+/-6.7 g whey proteins per kg milk. Electrophoresis and identification of protein bands showed a similar migrating sequence of proteins as seen in cheetah and cat milk, with small differences in the beta-caseins. The lipid fraction contains 313.3+/-18.8 g saturated and 338.6+/-11.9 g mono unsaturated fatty acids per kg milk fat respectively. The high content of 292.4+/-24.9 g kg(-1) milk fat of polyunsaturated fatty acids is due to a high content in linolenic acid. No short chain fatty acids, but substantial levels of uneven carbon chain fatty acids were observed. In general, serval milk has a higher protein and fat content than that of the domestic cat and cheetah, and a lower content of unsaturated fatty acids than that of the domestic cat.     

Growth rate of 21 captive-born,mother-raised cheetah cubs

This paper presents the growth rate of 21 clinically normal, mother-raised. captive cheetah cubs from birth through 45 days of age. The development of a growth curve for healthy, mother-raised cheetah cubs provides a diagnostic tool for individuals involved in cheetah propagation. Use of the curve may alert caretakers to problems early and thus help reduce the high neonatal mortality rate seen in captive-born cheetah cubs. The growth curve was constructed using 21 (11 males and 10 females) captiveborn cheetah cubs from six litters (offspring of three unrelated adult males and three unrelated adult females) born at the Columbus Zoo from September 1985 through December 1989. Each cub was weighed to the nearest gram the morning after birth and approximately the same time every consecutive morning for 45 days. The mean weight the morning after birth was 463 g (range 385–542 g). The average litter size was 3.5 (range 2–4, n = 6). The daily weight gain was 40–50 g/cub/day.     

Comparative evaluation of seminal,vaginal, and rectal bacterial flora in the cheetah and domestic cat

To determine the status and potential impact of microorganisms on reproductive health, bacterial cultures were evaluated from cheetah seminal, vaginal, and rectal swabs and the results compared to those from clinically healthy, domestic cats. Aerobic bacteria were isolated in the semen from 26 of the 40 (65.0%) cheetahs and 25 of the 27 (92.6%) domestic cats. Gram-negative organisms predominated in the electroejaculates of both species, accounting for >70% of the total bacterial isolates. The most common seminal organism in both species was hemolytic Escherichia coli. Bacteria were isolated from vaginal samples obtained from 49 of the 67 (73.1%) cheetahs and 46 of the 49 (93.9%) domestic cats. Gram-negative organisms dominated, representing >63% of the vaginal bacteria, and again hemolytic E. coli was the most prevalent isolate in both species. None of the cheetah or domestic cat vaginal cultures contained Mycoplasma spp. or Ureaplasma spp. Numerous gram-negative and gram-positive bacteria were identified in rectal cultures of 73 cheetahs and 60 domestic cats, but hemolytic E. coli clearly was the most common isolate. Within each species, a comparison between electroejaculates that were positive vs. negative for hemolytic E. coli growth revealed no differences in sperm concentration, sperm motility ratings, or the proportion of structurally abnormal spermatozoa. Neutrophils were not detected in any of the 67 felid ejaculates, and the presence of seminal hemolytic E. coli was unrelated to fertility, on the basis of past ability to sire young or fertilize oocytes in vitro. Vaginal cytologic evaluations in both the cheetah and domestic cat indicated that hemolytic E. coli was not associated with a pathologic inflammatory response. Overall fecundity and proven ability to produce young were similar between females producing positive or negative vaginal cultures for E. coli. These findings indicate that commensal bacteria exist in the reproductive tract of the cheetah and domestic cat, and these organisms constitute normal, apparently innocuous bacterial microflora in the semen and vagina. © 1993 Wiley-Liss, Inc.     

Distribution of muscle fibers in skeletal muscles of the cheetah (Acinonyx jubatus)

We examine the muscle fiber population of skeletal muscles from whole body in the cheetah (Acinonyx jubatus). In the present experiments, we showed the characteristics of fiber composition in the cheetah by comparative studies among the cheetah, domestic cat, and the beagle dog. Fiber population was determined on muscle fibers stained with monoclonal antibody to each myosin heavy chain isoform. Histochemical analysis demonstrated that many muscles in the cheetah and domestic cat had a low percentage of Type I fibers and a high percentage of Type IIx fibers, while those in the beagle dog showed a high percentage of Type IIa. The hindlimb muscles in the cheetah had a higher percentage of Type II (Type IIa + IIx) fiber than the forelimb muscles. This fact suggests that the propulsive role of the hindlimb is greater than the forelimb in the cheetah. The longissimus in the cheetah had a high percentage of Type IIx fibers over a wide range from the thoracic to lumbar parts, while the population of muscle fibers in this muscle was different depending on the parts in the domestic cat and beagle dog. This indicates that the cheetah can produce a strong and quick extension of the spinal column and increase its stiffness during locomotion. Furthermore, we found the notable difference of muscle fiber type population between flexors and extensors of digits in the cheetah. The present experiments show the characteristics of muscle fibers in the cheetah, corresponded to its ability to perform high-speed running.     

Oxidative phosphorylation is essential for felid sperm function, but is substantially lower in cheetah (Acinonyx jubatus) compared to domestic cat (Felis catus) ejaculate

Compared with the normospermic domestic cat, sperm metabolic function is compromised in the teratospermic cat and cheetah, but the pathway(s) involved in this deficiency are unknown. Glycolysis is essential for sperm motility, yet it appears to function normally in spermatozoa of either species regardless of structural morphology. We conducted a comparative study to further understand the mechanisms of energy production in felid spermatozoa, with the hypothesis that oxidative phosphorylation is required for normal sperm function and is impaired in teratospermic ejaculates. Electroejaculates from both species were stained with MitoTracker to quantify mitochondrial membrane potential (MMP) or were incubated to assess changes in sperm function (motility, acrosomal integrity, and lactate production) after mitochondrial inhibition with myxothiazol. Sperm midpiece dimensions also were quantified. Sperm mitochondrial fluorescence (directly proportional to MMP) was ~95% lower in the cheetah compared with the normospermic and teratospermic cat, despite the cheetah having a 10% longer midpiece. In both species, MMP was increased 5-fold in spermatozoa with retained cytoplasm compared with structurally normal cells. Inhibition of oxidative phosphorylation impaired sperm function in both species, but a 100-fold higher inhibitor concentration was required in the cat compared with the cheetah. Collectively, findings revealed that oxidative phosphorylation was required for sperm function in the domestic cat and cheetah. This pathway of energy production appeared markedly less active in the cheetah, indicating a species-specific vulnerability to mitochondrial dysfunction. The unexpected, cross-species linkage between retained cytoplasmic droplets and elevated MMP may reflect increased concentrations of metabolic enzymes or substrates in these structures.     

Polar Bear (Ursus maritimus) Adipose Tissue Fatty Acid Composition Compared to Fatty Acid Constituents of a Common Milk Replacer

This study compared the fatty acid composition of polar bear (Ursus maritimus) adipose tissue (n=2) to the fatty acid (FA) composition in published literature for maternal milk (n=3 samples) and a primary milk formula (liquid Esbilac, Pet Ag Inc., Hampshire, IL) commonly used in hand rearing, to look at possible dietary influences on ultimate body fat constituency. All tissue and commercial milk fatty acids were analyzed on a percent relative (% of fat) basis for consistency in reporting results and to make easier comparisons between samples with varying fat contents. Thirty‐eight individual fatty acid profiles were measured and the results tabulated into saturated, monounsaturated and polyunsaturated fats. The tissue adipose results for the two cubs had similar patterns throughout the assay. Saturated FA totals were 30% of the total fat, monounsaturated FA represented 50% of the total fat, and polyunsaturated FA was 15%. Similar fatty acid proportions were reported when comparing adipose to published data for maternal milk of polar bears. The most striking differences were between the commercial milk replacer (liquid Esbilac) and the tissue samples and maternal milk values. Esbilac FA summaries for saturated FAs were 24%, monounsaturated were 26%, and polyunsaturated comprised 50% of the total fat. Polyunsaturated fat in Esbilac is substantially higher than the tissue and milk scores. Although lipid sources from whole cream or half‐and‐half are used to increase the fat concentration of milk replacers for the hand‐reared polar bear cub, alternative ingredients such as fish oil may prove more suitable for this species, as their FA profiles better duplicate natural diets and resulting lipid stores in milk and adipose tissues of free‐ranging polar bears. Zoo Biol 0:1–11, 2006. © 2006 Wiley‐Liss, Inc.     

Effects of flaxseed supplementation on milk production,milk fatty acid composition and nutrient utilization by lactating dairy cows

Twelve multiparous Holstein cows at 72 ± 20 days in milk were used in a switch-back design with 14-d periods to determine the effect of replacing barley grain into a dairy total mixed ration with micronized or raw flaxseed on nutrient digestibility, milk yield, milk composition. Total mixed diets were (DM basis) 50% barley silage, 50% concentrate mix mainly rolled barley grain and canola meal. Diets were supplemented with 1 kg raw (RF) or micronized (MF) flaxseed to substitute 1 kg of rolled barley grain (C). Neutral detergent fibre, ADF and CP digestibility of the diets were not significantly affected by supplementation; however, calcium digestibility was reduced by 62% and 46% when raw and micronized flax were fed, respectively. Milk yield (38.3, 39.6, and 38.4 kg/d for diets C, RF and MF, respectively) was similar for all diets. Milk fat (3.50, 3.48, and 3.52%) and protein (3.31, 3.34, and 3.31%) for diets C, RF and MF, respectively, were not affected by treatment diets. Concentrations of c9, t11 conjugated linoleic acid (CLA; 0.51, 0.72 and 0.76 g/100 g fatty acids) in milk fat increased (P < 0.05) similarly among the two flaxseed supplemented diets. The RF and MF diets significantly increased the C18:1, C18:1 trans-11, C18:2 cis-9, cis-12 and C18:3 in milk fat however, C12:0, C14:0 and C16:0 were significantly reduced compared with control. Replacing barley grain with flaxseed in the diet of lactating cows increased the beneficial fatty acids in milk without depressing nutrient digestibility. Micronization of flaxseed did not reveal any advantage over raw flaxseed.     

Milk composition in free-ranging polar bears (Ursus maritimus) as a model for captive rearing milk formula

The goals of this study were to have an improved understanding of milk composition and to help create a suitable milk formula for cubs raised in captivity. Milk samples were evaluated for fat, fatty acids, carbohydrate, vitamin D(3), 25(OH)D(3), vitamin A (retinol), vitamin E (α-tocopherol), protein, and amino acids. Total lipids in milk did not differ for cubs (mean ± SEM = 26.60 ± 1.88 g/100 ml vs. yearlings 27.80 ± 2.20 g/100 ml). Milk lipids were of 23.6% saturated fatty acid for cubs and 22.4% for yearlings. Milk consumed by cubs and yearlings contained 43.8 and 42.0% mono-unsaturated fatty acids and 23.4 and 21.9% polyunsaturated fatty acids, respectively. Carbohydrate content was higher in milk for cubs (4.60 ± 0.64 g/100 ml) than for yearlings (2.60 ± 0.40 g/100 ml). Vitamin D(3) concentration of milk was 18.40 ± 5.00 ng/ml in early lactation compared with 7.60 ± 2.00 ng/ml for mid-lactation. 25(OH)D(3) was lower in milk consumed by cubs (162.00 ± 6.70 pg/ml) than in milk consumed by yearlings (205.00 ± 45.70 pg/ml). Vitamin A concentrations were 0.06 ± 0.01 and 0.03 ± 0.01 μg/ml for cubs and yearlings, respectively. Vitamin E was higher in milk consumed by cubs (20.16 ± 4.46 μg/ml) than by yearlings (7.30 ± 1.50 μg/ml). Protein content did not differ in milk available to cubs (11.40 ± 0.80 g/100 ml compared with milk for yearlings 11.80 ± 0.40 g/100 ml). Taurine was the most abundant free amino acid at 3,165.90 ± 192.90 nmol/ml (0.04% as fed basis).     

Correlation of sperm viability with gamete interaction and fertilization in vitro in the cheetah (Acinonyx jubatus).

Sperm-oocyte interaction in vitro was studied in the cheetah, a species known to produce poor quality ejaculates and to experience low rates of fertility. Twelve female cheetahs were injected (i.m.) with eCG followed by hCG 84 h later. Twenty-four to 26 h post hCG, each was subjected to laparoscopic oocyte aspiration. A sperm motility index (SMI) was calculated for each of 9 cheetah sperm donors that produced ejaculates averaging 41.3 +/- 22.9 x 10(6) motile sperm and 28.4 +/- 4.9% structurally normal sperm. Each ejaculate was used to inseminate cheetah oocytes from 1 or 2 females and salt-stored, domestic cat oocytes. The presence of ovarian follicles (greater than or equal to 1.5 mm in diameter) showed that all females responded to exogenous gonadotropins (range, 11-35 follicles/female). A total of 277 cheetah oocytes was collected from 292 follicles (94.9% recovery; 23.1 +/- 2.2 oocytes/female). Of these, 250 (90.3%) qualified as mature and 27 (9.7%) as degenerate. Of the 214 mature oocytes inseminated, 56 (26.2%) were fertilized, and 37 (17.3%) cleaved to the 2-cell stage in vitro; but the incidence of in vitro fertilization (IVF) varied from 0 to 73.3% (p less than 0.001) among individual males. When oocytes from individual cheetahs (n = 5) were separated into two groups and inseminated with sperm from a male with an SMI greater than 0 after 6 h coincubation versus an SMI = 0 at this time, the mean fertilization rates were 28/44 (63.6%) and 0/37 (0%), respectively (p less than 0.05). Of the 117 domestic cat oocytes coincubated with cheetah sperm, 96.6% contained 1 or more cheetah sperm in the outer half of the zona pellucida (ZP). Although the mean number of cheetah sperm penetrating the outer ZP of the cat oocyte was similar (p greater than 0.05) among all males, there was a positive correlation between the number of sperm reaching the inner half of the ZP and fertilization rate in vitro (r = 0.82; p less than 0.05). Compared to IVF efficiency in the domestic cat and tiger as reported in earlier studies, IVF efficiency in the cheetah is low. Because oocytes from 11 of 12 cheetahs were fertilized in vitro, there is no evidence that the female gamete is incompetent. Although sperm pleiomorphisms may contribute to poor reproductive performance, examination of the data on the basis of individual sperm donors reveals that effective gamete interaction in the cheetah is dictated, in part, by sperm motility.     

Performance of calves fed on milk replacers containing fish protein hydrolysate

Milk substitutes for calves are based upon dried skim milk and added fats of vegetable or animal origin. Many attempts have been made to replace part of the skim milk in these feeds by cheaper sources of protein.A milk product coagulates in the calf's abomasum and has a high digestibility. Milk replacers based on fish protein hydrolysate (FPH) do not coagulate in the abomasum, but have a high apparent digestibility coefficient (0.92) and the amino acid balance is similar to that of skim milk.Calves were fed on milk replacers prepared from FPH made from various materials. In general, FPH prepared from white fish (cod, blue whiting, white fish offal) was satisfactory although calf performance until weaning was poorer than for calves fed on milk replacers with dried skim milk (SMP). Some ways are suggested by which the quality of the product (FPH) could be maintained. FPH preparations from fatty fish, like sprats and mackerel, were also used. An antioxidant was added in the preparation of sprats and mackerel because of the unsaturated nature of fish fats. Milk replacers containing sprats prepared without an antioxidant and mackerel (31% body fat) with antioxidant were unsatisfactory and further development work is required on FPH materials from fatty fish.FPH from white fish can be dried without any appreciable loss in calf performance. The daily gain to weaning was 0.25 and 0.29 kg per day for calves fed on the dried and undried material, respectively. On the basis of present knowledge it is suggested that FPH can replace one third of skim milk in milk replacers for early weaned calves; the proportion recommended may rapidly increase with further technical development of the product.     

Decline in maternal immunity and antibody response to vaccine in captive cheetah (Acinonyx jubatus) cubs.

Blood was collected from captive cheetah cubs (Acinonyx jubatus) from the ages of 4 to 12 wk and monitored for the decline in maternally derived antibodies to feline panleukopenia, herpes and calici viruses. A steady decrease was seen in most of the cubs. Antibody responses to inactivated and/or modified live virus (MLV) vaccine also were measured. The strongest responses were seen post vaccination with MLV vaccine only.     

The composition of cheetah (Acinonyx jubatus) milk

Milk was obtained from two captive bred cheetahs. The nutrient content was 99.6 g protein; 64.8 g fat; and 40.21 g lactose per kg milk. Small amounts of oligosaccharides, glucose, galactose and fucose were noted. The protein fraction respectively consisted of 34.2 g caseins per kg milk and of 65.3 g whey proteins per kg milk. Very little variation in milk composition among the individual cheetahs was noted. Electrophoresis and identification of protein bands showed a similar migrating sequence of proteins as seen in lion's and cat's milk, with small differences in the β-caseins. The lipid fraction contains 290.4 g saturated and 337.3 g mono-unsaturated fatty acids per kg milk fat respectively. The high content of 279.5 g kg^− 1 milk fat of polyunsaturated fatty acids is due to a high content in α-linolenic acid. No short chain fatty acids, but substantial levels of uneven carbon chain fatty acids were observed.     

Glycolytic enzyme activity is essential for domestic cat (Felis catus) and cheetah (Acinonyx jubatus) sperm motility and viability in a sugar-free medium

We have previously reported a lack of glucose uptake in domestic cat and cheetah spermatozoa, despite observing that these cells produce lactate at rates that correlate positively with sperm function. To elucidate the role of glycolysis in felid sperm energy production, we conducted a comparative study in the domestic cat and cheetah, with the hypothesis that sperm motility and viability are maintained in both species in the absence of glycolytic metabolism and are fueled by endogenous substrates. Washed ejaculates were incubated in chemically defined medium in the presence/absence of glucose and pyruvate. A second set of ejaculates was exposed to a chemical inhibitor of either lactate dehydrogenase (sodium oxamate) or glyceraldehyde-3-phosphate dehydrogenase (alpha-chlorohydrin). Sperm function (motility and acrosomal integrity) and lactate production were assessed, and a subset of spermatozoa was assayed for intracellular glycogen. In both the cat and cheetah, sperm function was maintained without exogenous substrates and following lactate dehydrogenase inhibition. Lactate production occurred in the absence of exogenous hexoses, but only if pyruvate was present. Intracellular glycogen was not detected in spermatozoa from either species. Unexpectedly, glycolytic inhibition by alpha-chlorohydrin resulted in an immediate decline in sperm motility, particularly in the domestic cat. Collectively, our findings reveal an essential role of the glycolytic pathway in felid spermatozoa that is unrelated to hexose metabolism or lactate formation. Instead, glycolytic enzyme activity could be required for the metabolism of endogenous lipid-derived glycerol, with fatty acid oxidation providing the primary energy source in felid spermatozoa.     

Antimicrobial activity of lipids added to human milk,infant formula,and bovine milk

Lipids previously shown to have antiviral and antibacterial activity in buffers were added to human milk, bovine milk, and infant formulas to determine whether increased protection from infection could be provided to infants as part of their diet. Fatty acids and monoglycerides with chain lengths varying from 8 to 12 carbons were found to be more strongly antiviral and antibacterial when added to milk and formula than long chain monoglycerides. Lipids added to milk and formula inactivated a number of pathogens including respiratory syncytial virus (RSV), herpes simplex virus type 1 (HSV-1), Haemophilus influenzae, and Group B streptococcus. The results presented in this study suggest that increased protection from infection may be provided to infants at mucosal surfaces, prior to the digestion of milk and formula triglycerides, by the addition of antimicrobial medium chain monoglycerides to an infant's diet.     

Cub growth and maternal care in cheetahs

Using cub growth as an index, I examine the influence of maternalnutrition, litter size, and cub sex on maternal care in cheetahs(Acinonyx jubatus) and compare cub and litter growth rates withthose of other large feilds. Seventy-nine free-living cheetahcubs in 21 litters from 15 mothers were weighed at least oncebetween 6 and 48 days of age. Eleven litters were weighed atthe beginning and end of a 5-day observation of their mothers.The mean cub growth rate varied significantly between litters,due primarily to differences in maternal food intake. Growthdeclined sharply when maternal food intake was less than 1.5kg/ day, but did not increase with greater levels of food intake.Lower limits of growth rates may therefore have been set bythe mother's food intake, whereas upper limits may be set bythe intrinsic physiological ability of cubs to grow. Althoughmale cubs were heavier than female cubs in the same litter whenfirst weighed, major differences in growth rate between thesexes were not apparent at this stage. Both cheetah cubs andlitters grow fast relative to other large felids, and I arguethat this may be an adaptation to the high rate of cheetah juvenilemortality from predation.     

High juvenile mortality in cheetahs (Acinonyx jubatus) and its consequences for maternal care

Juvenile mortality in cheetahs was found to be extremely high compared to other large mammals, with approximately 72.2% of litters dying before they emerged from the lair at eight weeks of age. An average of 83.3% of cubs alive at emergence died by adolescence at 14 months of age, thus cheetah cubs were estimated to have only a 4.8% chance of reaching independence at birth. The instantaneous rate of mortality was highest immediately after cubs emerged from the lair. Before emergence, lion predation was the major source of this mortality, although some cubs died from starvation after they were abandoned by their mothers, or as a result of grass fires and inclement weather. After emergence, predation again accounted for virtually all cub mortality, with lions and spotted hyaenas taking approximately the same proportion of cubs. Overall predation accounted for 73.2% of cheetah cub deaths in this study, with 78.2% of these being killed by lions. The extent of maternal care, in the form of vigilance and antipredator behaviour, mirrored cub susceptibility to mortality and, in the case of vigilance, possibly also starvation. The probability of a cheetah mother responding aggressively to a predator was found also to depend on the species of predator. This study highlights the importance of the influence of juvenile mortality on patterns of parental care.     

Chemical structures of oligosaccharides in milks of the American black bear (Ursus americanus americanus) and cheetah (Acinonyx jubatus)

The milk oligosaccharides were studied for two species of the Carnivora: the American black bear (Ursus americanus, family Ursidae, Caniformia), and the cheetah, (Acinonyx jubatus, family Felidae, Feliformia). Lactose was the most dominant saccharide in cheetah milk, while this was a minor saccharide and milk oligosaccharides predominated over lactose in American black bear milk. The structures of 8 neutral saccharides from American black bear milk were found to be Gal(β1–4)Glc (lactose), Fuc(α1–2)Gal(β1–4)Glc (2′-fucosyllactose), Gal(α1–3)Gal(β1–4)Glc (isoglobotriose), Gal(α1–3)[Fuc(α1–2)]Gal(β1–4)Glc (B-tetrasaccharide), Gal(α1–3)[Fuc(α1–2)]Gal(β1–4)[Fuc(α1–3)]Glc (B-pentasaccharide), Fuc(α1–2)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)Glc (difucosyl lacto-N-neotetraose), Gal(α1–3)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)Glc (monogalactosyl monofucosyl lacto-N-neotetraose) and Gal(α1–3)Gal(β1–4)GlcNAc(β1–3)Gal(β1–4)Glc (Galili pentasaccharide). Structures of 5 acidic saccharides were also identified in black bear milk: Neu5Ac(α2–3)Gal(β1–4)Glc (3′-sialyllactose), Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)[Fuc(α1–2)Gal(β1–4)GlcNAc(β1–6)]Gal(β1–4)Glc (monosialyl monofucosyl lacto-N-neohexaose), Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)[Gal(α1–3)Gal(β1–4)GlcNAc(β1–6)]Gal(β1–4)Glc (monosialyl monogalactosyl lacto-N-neohexaose), Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3){Gal(α1–3)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–6)}Gal(β1–4)Glc (monosialyl monogalactosyl monofucosyl lacto-N-neohexaose), and Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3){Gal(α1–3)[Fuc(α1–2)]Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–6)}Gal(β1–4)Glc (monosialyl monogalactosyl difucosyl lacto-N-neohexaose). A notable feature of some of these milk oligosaccharides is the presence of B-antigen (Gal(α1–3)[Fuc(α1–2)]Gal), α-Gal epitope (Gal(α1–3)Gal(β1–4)Glc(NAc)) and Lewis x (Gal(β1–4)[Fuc(α1–3)]GlcNAc) structures within oligosaccharides. By comparison to American black bear milk, cheetah milk had a much smaller array of oligosaccharides. Two cheetah milks contained Gal(α1–3)Gal(β1–4)Glc (isoglobotriose), while another cheetah milk did not, but contained Gal(β1–6)Gal(β1–4)Glc (6′-galactosyllactose) and Gal(β1–3)Gal(β1–4)Glc (3′-galactosyllactose). Two cheetah milks contained Gal(β1–4)GlcNAc(β1–3)[Gal(β1–4)GlcNAc(β1–6)]Gal(β1–4)Glc (lacto-N-neohexaose), and one cheetah milk contained Gal(β1–4)Glc-3’-O-sulfate. Neu5Ac(α2–8)Neu5Ac(α2–3)Gal(β1–4)Glc (disialyllactose) was the only sialyl oligosaccharide identified in cheetah milk. The heterogeneity of milk oligosaccharides was found between both species with respect of the presence/absence of B-antigen and Lewis x. The variety of milk oligosaccharides was much greater in the American black bear than in the cheetah. The ratio of milk oligosaccharides-to-lactose was lower in cheetah (1:1–1:2) than American black bear (21:1) which is likely a reflection of the requirement for a dietary supply of N-acetyl neuraminic acid (sialic acid), in altricial ursids compared to more precocial felids, given the role of these oligosaccharides in the synthesis of brain gangliosides and the polysialic chains on neural cell adhesion.

     

Composition of uterine milk and its changes with gestational period in red stingrays (Hemitrygon akajei)

Uterine milk is secreted in the uterus for embryo nutrition in several elasmobranch species and may contribute to rapid embryonic growth, but the details of its composition and its functions are poorly understood. In this study, to explore the roles of uterine milk for embryos, its components throughout the gestational period were analysed in detail. Uterine milk was collected from pregnant red stingrays (Hemitrygon akajei) in the early, middle and late gestational periods, respectively (n= 3 for each period). The crude composition, constituent proteins and fatty acids in the milk were analysed. The uterine milk was rich in proteins throughout the gestational period, whereas lipids dramatically increased in the middle period and reduced slightly towards the late period. Some proteins potentially associated with nutrition, cartilage growth and embryonic immunity were found. Several enzymes related to central metabolism were also detected. The constituent fatty acids in the middle and late periods were similar to those in the egg yolks of elasmobranchs, except for C18:2, which was rich only in the uterine milk. The most abundant fatty acid in the milk was C16:1, which could function as a lipokine to promote lipid metabolism in the embryo. This study's data suggest that uterine milk may be secreted in addition to the egg yolk in elasmobranchs to support rapid and healthy embryonic growth.     

Soluble form of ICAM-1, VCAM-1, E- and L-selectin in human milk

In breast milk and paired serum from 70 lactating women and 40 of their term, infection-free neonates, on the 2nd and 5th day postpartum slCAM-1, sVCAM-1, sE- and sL-selectin were measured by ELISA and compared with those in 26 healthy adults (controls). Seven infant formulas and fresh milk from five cows were also analyzed. Human colostrum values of slCAM-1, sVCAM-1 (similar to those in maternal and control serum), sE-selectin and sL-selectin (-10 and -100 times lower than in maternal and control serum) were significantly higher than those in milk, while they varied widely. None of the adhesion molecules was detected in fresh cow's milk or infant formulas. Exclusively breast-fed infants showed significantly higher values of slCAM-1 and sL-selectin on the 2nd day of life than those supplemented also with formula. Only slCAM-1 values correlated positively between colostrum and time-matched maternal serum. These findings show in human milk important amounts of slCAM-1 and sVCAM-1 but minimal amounts of sE- and sL-selectin, which could affect the immune system of the neonate.