Replacement Feeding Research Articles

Suitability of n-alkanes and chromium (III) oxide as digestibility markers in calves at the end of the milk feeding period supplemented with a prebiotic.

Prebiotics reveal positive effects on the growth performance of pigs and poultry, and might influence intestinal microflora. This, in consequence, could alter recovery rates of digestibility markers. In the current study, we evaluated the suitability of chromium (III) oxide (Cr2O3) and the synthetic alkanes n-dotriacontane (C32) and n-hexatriacontane (C36) as external markers for digestibility estimation compared with the standard total collection method in calves supplemented with galacto-oligosaccharides. Eight male German Holstein calves (average age ± SD = 57 ± 8 days) were divided into 2 milk replacer feeding groups (group receiving galacto-oligosaccharides [A] and control group [B]). Each of 2 groups of 4 individually fed calves received a distinct milk replacer with added markers for 14 days. They were fed twice daily restrictively with milk replacer, concentrate and hay. After an adaptation period of 10 days, total faeces were collected. Faecal marker recoveries (FMR, means ± SD) for C32 were (72 ± 14)% for A and (80 ± 12)% for B. Faecal marker recoveries for C36 was (82 ± 15)% and (88 ± 13)% for groups A and B, respectively. The FMR for Cr2O3 was (102 ± 11)% and (100 ± 1)% for groups A and B, respectively. There were no significant differences between total collection organic matter digestibility and marker based organic matter digestibility when using Cr2O3 and C36. But, when utilizing C32 to calculate nutrient digestibilities, results differed from the total collection method for organic matter, crude protein and ether extract. The results indicate that Cr2O3 and C36 can be applied in digestibility studies with calves and give accurate estimates for OM and nutrient digestibilities without correction for FMR.

Effects of feeding unlimited amounts of milk replacer for the first 5 weeks of age on rumen and small intestinal growth and development in dairy calves

The development of the gastrointestinal tract in newborn calves is essential for sufficient nutrient uptake. An intensive milk feeding during the neonatal period may impair the rumen development in calves. The aim of this study was to investigate effects of milk replacer (MR) feeding in unlimited amounts for the first 5 wk of age on the gastrointestinal growth and development in preruminant calves at wk 9 of age. Twenty-eight newborn Holstein and Holstein × Charolais crossbred calves (19 male and 9 female) were fed MR ad libitum (ADLIB) or in restricted amounts (6 L per day; RES) until wk 5 of age. Thereafter, the MR intake of ADLIB was gradually reduced at wk 6 and 7, and all calves received 6 L of MR per day until wk 9 of age. In wk 9, calves were slaughtered and carcass and organ weight as well as rumen papilla size in the atrium, ventral sac, and ventral blind sac, and villus size of the mucosa in the small intestine (duodenum; proximal, mid, and distal jejunum; and ileum) were determined. The expression of mRNA associated with the local insulin-like growth factor (IGF) system was measured in the rumen epithelium. Ad libitum MR feeding increased MR intake and growth in ADLIB without influencing concentrate intake compared with RES. Carcass weight in wk 9 was greater in ADLIB than in RES. The density of the rumen papillae in the atrium and ventral blind sac was greater in RES than in ADLIB calves, but surface area of the epithelium was not different between groups in the investigated regions of the rumen. The mRNA abundance of IGF1 in the atrium tended to be greater and the IGFR1 mRNA abundance in the ventral sac tended to be lower in the ADLIB than in the RES feeding group. The rumen pH and volatile fatty acid concentrations were not affected by MR feeding intensity. In mid-jejunum, villus circumference was greater in ADLIB than in RES calves. In the distal jejunum, villus surface area and the villus height/crypt depth ratio were greater and the villus circumference and height tended to be greater, whereas crypt depth was smaller in ADLIB than in RES calves. The findings from this study indicate that ad libitum MR feeding for 5 wk of age followed by its gradual reduction promotes growth performance without any negative influence on gastrointestinal growth and development in dairy calves at 9 wk of age.

Vitamin A supplements for reducing mother-to-child HIV transmission.

BackgroundStrategies to reduce the risk of mother‐to‐child transmission of the human immunodeficiency virus (HIV) include lifelong antiretroviral therapy (ART) for HIV‐positive women, exclusive breastfeeding from birth for six weeks plus nevirapine or replacement feeding plus nevirapine from birth for four to six weeks, elective Caesarean section delivery, and avoiding giving children chewed food. In some settings, these interventions may not be practical, feasible, or affordable. Simple, inexpensive, and effective interventions (that could potentially be implemented even in the absence of prenatal HIV testing programmes) would be valuable. Vitamin A, which plays a role in immune function, is one low‐cost intervention that has been suggested in such settings.ObjectivesTo summarize the effects of giving vitamin A supplements to HIV‐positive women during pregnancy and after delivery.Search methodsWe searched the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Embase, and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) up to 25 August 2017, and checked the reference lists of relevant articles for eligible studies.Selection criteriaWe included randomized controlled trials conducted in any setting that compared vitamin A supplements to placebo or no intervention among HIV‐positive women during pregnancy or after delivery, or both.Data collection and analysisAt least two review authors independently assessed study eligibility and extracted data. We expressed study results as risk ratios (RR) or mean differences (MD) as appropriate, with their 95% confidence intervals (CI), and conducted random‐effects meta‐analyses. This is an update of a review last published in 2011.Main resultsFive trials met the inclusion criteria. These were conducted in Malawi, South Africa, Tanzania, and Zimbabwe between 1995 and 2005 and none of the participants received ART. Women allocated to intervention arms received vitamin A supplements at a variety of doses (daily during pregnancy; a single dose immediately after delivery, or daily doses during pregnancy plus a single dose after delivery). Women allocated to comparison arms received identical placebo (6601 women, 4 trials) or no intervention (697 women, 1 trial). Four trials (with 6995 women) had low risk of bias and one trial (with 303 women) had high risk of attrition bias.The trials show that giving vitamin A supplements to HIV‐positive women during pregnancy, the immediate postpartum period, or both, probably has little or no effect on mother‐to‐child transmission of HIV (RR 1.07, 95% CI 0.91 to 1.26; 4428 women, 5 trials, moderate certainty evidence) and may have little or no effect on child death by two years of age (RR 1.06, 95% CI 0.92 to 1.22; 3883 women, 3 trials, low certainty evidence). However, giving vitamin A supplements during pregnancy may increase the mean birthweight (MD 34.12 g, 95% CI −12.79 to 81.02; 2181 women, 3 trials, low certainty evidence) and probably reduces the incidence of low birthweight (RR 0.78, 95% CI 0.63 to 0.97; 1819 women, 3 trials, moderate certainty evidence); but we do not know whether vitamin A supplements affect the risk of preterm delivery (1577 women, 2 trials), stillbirth (2335 women, 3 trials), or maternal death (1267 women, 2 trials).Authors' conclusionsAntepartum or postpartum vitamin A supplementation, or both, probably has little or no effect on mother‐to‐child transmission of HIV in women living with HIV infection and not on antiretroviral drugs. The intervention has largely been superseded by ART which is widely available and effective in preventing vertical transmission.2 April 2019Up to dateAll studies incorporated from most recent searchUpdated review: all eligible published studies found in the last search (25 Aug, 2017) were included

Effects of egg yolk inclusion, milk replacer feeding rate, and low-starch (pelleted) or high-starch (texturized) starter on Holstein calf performance through 4 months of age

The objectives of this research were to evaluate milk replacer (MR) feeding rates, alternative protein and fat sources in MR, and calf starter starch concentration and their effects on calf performance to 4 mo of age. Male Holstein calves (42.6 ± 1.2 kg of body weight; n = 192) were assigned at 3 d of age to 1 of 8 treatments in a randomized complete block design with a 2 × 2 × 2 factorial arrangement of treatments. Factors tested from d 0 to 56 (nursery) were low or high MR feeding rates, 0 or 10% inclusion of spray-dried egg yolks in MR, and low- or high-starch calf starter. The low MR rate was 0.66 kg of dry matter (DM) fed for 39 d followed by 0.33 kg of DM for 3 d. The high MR rate was 0.87 kg of DM fed for 5 d, 1.08 kg of DM for 37 d, and 0.43 kg of DM for 7 d. The MR contained 27.5% crude protein and 19.6% fat (DM basis) and starters were 21.2% crude protein; low starch was a complete pellet with 10.2% starch, and high starch was textured using whole corn and oats with 43.3% starch. From d 56 to 112 (grower), calves were randomly assigned to pens (4 calves/pen) maintaining MR rate and starch content while stratifying yolk treatments within pen, resulting in a 2 × 2 factorial arrangement. Starter was blended with 5% chopped hay during the grower trial. Fecal scores and medical treatments were recorded daily. In the nursery trial, calves were weighed initially and weekly thereafter. Hip width and body condition score (BCS) were measured initially and every 2 wk thereafter. In the grower trial, body weight, hip width, and BCS were measured on d 56, 84, and 112. Data were analyzed as repeated measures with calf (nursery) or pen (grower) as the experimental unit. Calf average daily gain, hip width, and BCS change were greater for calves fed high versus low MR, 0 versus 10% yolk, and high versus low starch in the nursery. In the grower trial, calves fed low MR and high starch had the greatest average daily gain (1.09 vs. 0.87 kg/d) and hip width change (5.4 vs. 3.9 cm) compared with calves fed low MR and low starch with other treatments intermediate. From 0 to 112 d, calves fed high MR had 9% greater body weight gain and 4% greater hip width change than calves fed low MR, yet nutrient efficiency was similar despite 80% more MR intake than calves fed low MR. Additionally, calves fed high-starch starter achieved 18% greater body weight gain and 17% greater hip width than calves fed low starch starter overall, a more than 2-fold greater response than the effect of MR feeding rate.

Barren diets increase wakeful inactivity in calves

Inactivity is a vastly understudied behavioural category, which may reflect positive or negative affective states in captive or domesticated animals. Increased inactivity in barren-housed animals, in combination with an increased or decreased interest in stimuli, e.g. novel objects, can indicate boredom or apathy. Another theory is that inactivity is an alternative strategy to stereotypies to cope with sub-optimal conditions. The aim of this study was to further our understanding of inactive behaviours and possible associated negative affective states in intensively raised calves fed different diets. In two separate experiments, Holstein-Friesian veal calves (N=40+160) were fed barren or enriched diets: 1) imposed/restricted diet versus free dietary choice (experiment 1); 2) no additional straw versus ad libitum provision of straw (experiment 2); 3) low versus high solid feed provision (experiment 2); 4) bucket versus automated milk dispenser for milk replacer feeding, with high or low solid feed provision (experiment 2). Inactive behaviours, i.e. experiment 1: lie, idle and sleep; experiment 2: lie idle, stand idle, and sleep, were recorded at two ages (experiment 1: 12 and 26wk; experiment 2: 15 and 24wk) using instantaneous scan sampling. In experiment 2, latency to touch two novel objects was recorded at 15 and 24wk. No differences in inactivity were found between calves with a restricted or free choice diet (experiment 1). However, calves fed the more barren diets in experiment 2 showed more lying idle at 24wk of age, and calves with no ad libitum straw in particular, showed more standing idle at 24wk of age (P<0.05). No differences in latency to touch the novel objects were found. Therefore, although barren diets were generally associated with higher levels of inactivity, we found no support that this inactivity reflected boredom or apathy. Only weak associations were found between inactivity and stereotypies, providing only limited support for the idea that these constitute alternative strategies to cope with sub-optimal conditions.

Ad libitum milk replacer feeding, but not butyrate supplementation, affects growth performance as well as metabolic and endocrine traits in Holstein calves.

The enhanced growth performance of calves fed a higher plane of nutrition pre-weaning is well documented, and the effect of butyrate on the development of the gastrointestinal tract in calves has been evaluated. The aim of this study was to examine the synergistic effects of ad libitum milk replacer (MR) feeding and butyrate supplementation on growth performance and energy metabolism in calves. Sixty-four (32 male, 32 female) Holstein calves were examined from birth until wk 11 of life. Calves received MR either ad libitum (Adl) or restrictively (Res) with (AdlB+, ResB+) or without (AdlB-, ResB-) 0.24% butyrate supplementation. Colostrum and transition milk were fed in predefined amounts (Res or Adl) for the first 3 d postpartum. Ad libitum and restrictive MR feeding with or without butyrate was performed from d 4 until wk 8 of age. From wk 9 to 10, all calves were gradually weaned and were fed 2 L/d until the end of the trial. Concentrate (CON), hay, and water were freely available. Intakes of MR and CON were measured daily. Calves were weighed at birth and weekly thereafter. Blood was drawn on d 1 before the first colostrum intake; on d 2, 4, and 7; and weekly thereafter until the end of the study to measure plasma concentrations of metabolites and hormones. Liver samples were taken at d 50 and at the end of the study to determine gene expression related to glucose metabolism. Milk, MR, and total nutrient intake were greater, but CON intake was lower in Adl than in Res calves, resulting in a greater body weight, but partially lower gain to feed ratio in Adl than in Res. Plasma concentrations of glucose and insulin were higher during the ad libitum milk-feeding period, whereas plasma β-hydroxybutyrate was lower in Adl than in Res. Plasma concentrations of nonesterified fatty acids, lactate, total bilirubin, and cortisol were lower, but triglyceride and cholesterol concentrations were higher in Adl than in Res at specific time points. Feed intake, growth performance, and metabolic and endocrine changes were insignificantly affected by butyrate, and hepatic gene expression of enzymes related to endogenous glucose production was barely influenced by ad libitum MR feeding and butyrate supplementation. Intensive MR feeding indicated greater stimulation of growth and anabolic metabolism, but butyrate supplementation did not further improve postnatal growth or anabolic processes either in intensive or restrictive MR-fed calves.

Short communication: Use of fecal starch concentration as an indicator of dry feed digestion in preweaned dairy calves.

Fecal starch (FS) has been used as a tool to evaluate starch and diet digestibility in lactating dairy cows and feedlot steers. Some on-farm advisors also use FS to evaluate calf starter digestibility in preweaned dairy calves. Our objective was to evaluate the influence of starter intake (SI), starch and organic matter digestibility, milk replacer (MR) feeding rate, and age on FS concentrations in preweaned dairy calves. Male Holstein calves (43 ± 2.9 kg of body weight; n = 35) from a single farm were fed different amounts of MR ranging from 0.44 to 1.10 kg of dry matter (DM) daily (27% crude protein, 17% fat) and weaned by 7 wk of age. Starter ingredient composition was 37% whole corn, 20% whole oats, 35% protein pellet, and 3% molasses and contained 43 ± 1.9% starch. Fecal grab samples were taken at 3 (n = 20), 6 (n = 20), and 8 wk (n = 35) of age. Twelve fecal samples per calf were taken via rectal palpation over a 5-d period each week, frozen daily, combined on an equal wet-weight basis, and subsampled for analysis. Chromic oxide was used as an external digestibility marker at 3 and 6 wk (included in MR), whereas acid-insoluble ash was used as an internal marker at 8 wk. Milk replacer and starter intakes (offered and refused) were recorded daily during collection periods. Multiple and linear regression of organic matter digestibility (% of DM), total-tract starch digestibility (TTSD; % of DM), MR intake (kg/d), SI (kg/d), and age (week) versus FS (% of fecal DM) were determined using PROC REG of SAS (version 9.2, SAS Institute Inc., Cary, NC). Prior to weaning, SI, age, and MR rate explained 89% of the variation in TTSD, where TTSD = [19.7 × SI (±4.25)] + [3.8 × age (±0.79)] - [24.8 × MR (±3.19)] + 56.2 (±3.39). At 3 wk of age, TTSD increased (coefficient of determination = 0.53) and SI decreased (coefficient of determination = 0.20) with increasing FS. At 6 wk of age, TTSD and SI were unrelated to FS. In 8-wk-old calves (with 2 trials), SI, MR rate, FS, and trial explained 92% of the variation in TTSD, where TTSD = -[2.6 × SI (±0.67)] - [2.4 × MR (±0.56)] - [0.6 × FS (±0.04)] + [1.1 × trial (±0.33)] + 100.4 (±1.02). Postweaning, TTSD decreased linearly as FS increased (coefficient of determination = 0.86), whereas FS and SI were unrelated, a relationship in contrast to the previously observed result in calves still consuming milk replacer. In the current study, FS was not a good estimate of TTSD or dry feed intake in the preweaned calf, but has potential for evaluating TTSD in calves after weaning.

PHYSIOLOGY AND ENDOCRINOLOGY SYMPOSIUM: Postnatal reproductive development and the lactocrine hypothesis.

Maternal effects on development can program cell fate and dictate offspring phenotype. Such effects do not end at birth, but extend into postnatal life through signals communicated from mother to offspring in first milk (colostrum). Transmission of bioactive factors from mother to offspring as a specific consequence of nursing defines a lactocrine mechanism. The female reproductive tract is not fully formed at birth (postnatal day = PND 0). Data for ungulates and mice indicate that disruption of development during neonatal life can have lasting effects on the form and function of uterine tissues. Uterine growth and histogenesis proceed in an ovary-independent manner shortly after birth, suggesting that extra-ovarian inputs are important in this process. Data for the pig indicate that lactocrine signals communicated within 12 to 48 h from birth constitute one source of such uterotrophic support. Disruption of lactocrine signaling, either naturally, by limited colostrum consumption, or experimentally, by milk replacer feeding, alters neonatal porcine uterine development and can have negative consequences for reproductive performance in adults. Substantial differences in endometrial and uterine gene expression between colostrum- and replacer-fed gilts were evident by PND 2, when RNA sequencing revealed over 800 differentially expressed, lactocrine-sensitive genes. Lactocrine-sensitive biological processes identified through transcriptomic studies and integrated microRNA-mRNA pathway analyses included those associated with both cell-cell and ESR1 signaling, and tissue development. Evidence for the pig indicates that colostrum consumption and lactocrine signaling are required to establish a normal uterine developmental program and optimal uterine developmental trajectory.

Antiretroviral Treatment in HIV-1-Positive Mothers: Neurological Implications in Virus-Free Children.

Since the worldwide introduction of antiretroviral therapy (ART) in human immunodeficiency virus type 1, HIV-1-positive mothers, together with HIV-1 testing prior to pregnancy, caesarian birth and breastfeeding cessation with replacement feeding, a reduction of HIV-1 mother-to-child transmission (MTCT) has been observed in the last few years. As such, an increasing number of children are being exposed in utero to ART. Several questions have arisen concerning the neurological effects of ART exposure in utero, considering the potential effect of antiretroviral drugs on the central nervous system, a structure which is in continuous development in the fetus and characterized by great plasticity. This review aims at discussing the possible neurological impairment of children exposed to ART in utero, focusing attention on the drugs commonly used for HIV-1 MTCT prevention, clinical reports of ART neurotoxicity in children born to HIV-1-positive mothers, and neurologic effects of protease inhibitors (PIs), especially ritonavir-“boosted” lopinavir (LPV/r) in cell and animal central nervous system models evaluating the potential neurotoxic effect of ART. Finally, we present the findings of a meta-analysis to assess the effects on the neurodevelopment of children exposed to ART in utero.

Evaluation of an accelerated growth program for pre-weaned Shall lambs

In order to evaluate the effect of source and amount of milk delivered to lambs on their performance, thirty newborn Shall male lambs (4.76±0.31kg) were randomly assigned to one of three treatments: 1) conventional whole milk feeding program at 10% of body weight (CWM); 2) conventional milk replacer feeding at 10% of body weight and 17.1% milk solid (MRC); 3) accelerated milk replacer feeding program at 20% of body weight and 21% milk solid (MRA). Lambs were weaned at 56 d of age and the experiment finished 2 week after weaning. Milk and solid feed intakes were individually recorded on a daily basis. As the experiment advanced, the solid feed consumption (P<0.01) and average daily gain (ADG; P<0.01) increased, but MRC fed lambs had a decreased ADG compared to CWM or MRA groups in the pre-weaning (94g/day vs. 140 and 155g/day, respectively), but not in post-weaning, phase. The accelerated program led to decreased solid feed intake in the MRA group while the other lambs had similar starter intake, though total dry matter intake was greater in MRA compared with others. The CWM group had the best gain:feed ratio, resulting in similar final body weights as the MRA group and greater body weights compared with MRC lambs. Circulating β-hydroxy butyric acid was decreased (P<0.01) in MRA lambs compared with lambs on the traditional program during pre-weaning, but not post-, weaning period. In conclusion, it appears that lambs can be artificially reared on very low fat MRA program with greatly improved ADG during the first month of life, but, without altering final performance.

Maternal supplementation with rumen-protected methionine increases prepartal plasma methionine concentration and alters hepatic mRNA abundance of 1-carbon, methionine, and transsulfuration pathways in neonatal Holstein calves

An important mechanism of nutritional "programming" induced by supplementation with methyl donors during pregnancy is the alteration of mRNA abundance in the offspring. We investigated the effects of rumen-protected Met (RPM) on abundance of 17 genes in the 1-carbon, Met, and transsulfuration pathways in calf liver from cows fed the same basal diet without (control, CON) or with RPM at 0.08% of diet dry matter/d (MET) from -21 through +30 d around calving. Biopsies (n = 8 calves per diet) were harvested on d 4, 14, 28, and 50 of age. Cows fed RPM had greater plasma concentration of Met (17.8 vs. 28.2 μM) at -10 d from calving. However, no difference was present in colostrum yield and free AA concentrations. Greater abundance on d 4 and 14 of betaine-homocysteine S-methyltransferase 2 (BHMT2), adenosylhomocysteinase (AHCY; also known as SAHH), and cystathionine-β-synthase (CBS) in MET calves indicated alterations in Met, choline, and homocysteine metabolism. Those data agree with the greater abundance of methionine adenosyltransferase 1A (MAT1A) in MET calves. Along with CBS, the greater abundance of glutamate-cysteine ligase (GCLC) and glutathione reductase (GSR) on d 4 in MET calves indicated a short-term postnatal alteration in the use of homocysteine for taurine and glutathione synthesis (both are potent intracellular antioxidants). The striking 7-fold upregulation at d 50 versus 4 of cysteine sulfinic acid decarboxylase (CSAD), catalyzing the last step of taurine synthesis, in MET and CON calves underscores an important role of taurine during postnatal calf growth. The unique role of taurine in the young calf is further supported by the upregulation of CBS, GCLC, and GSR at d 50 versus 14 and 28 in MET and CON. Although betaine-homocysteine S-methyltransferase (BHMT) activity did not differ in MET and CON, it increased ∼50% at d 14 and 28 versus 4. A significant positive correlation (r = 0.79) was present between BHMT abundance and BHMT activity regardless of treatment. The gradual upregulation over time of BHMT2 and SAHH coupled with the gradual upregulation of MAT1A and the DNA (cytosine-5-)-methyltransferases (DNMT1, DNMT3A, DNMT3B) in MET and CON calves was indicative of adaptations potentially driven by differences in intake of milk replacer and starter feed as calves grew. In that context, the ∼2.5-fold increase in abundance of DNMT3B at d 50 versus 4 in MET and CON indicate that DNA methylation might be an important component of the physiologic adaptations of calf liver. The data indicate that calves from MET-supplemented cows underwent alterations in Met, choline, and homocysteine metabolism partly to synthesize taurine and glutathione, which would be advantageous for controlling metabolic-related stress. Whether the effects in MET calves were directly related to increased Met supply in utero remains to be determined.

Different milk feeding intensities during the first 4 weeks of rearing in dairy calves: Part 1: Effects on performance and production from birth over the first lactation

We aimed to test the effects of ad libitum feeding of whole milk (WM) or milk replacer (MR) versus restrictive feeding of MR during the first 4 wk of life on growth performance and on milk yield in the first lactation. We studied 57 German Holstein calves (29 females, 28 males) from birth until d 110 of life (trial 1). The 28 females from trial 1 were further studied during their first lactation (trial 2). In trial 1, all calves were randomly allocated at birth to 1 of 3 groups: MR-res [n = 20, 6.78 kg MR (11.5% solids)/calf per day], MR-ad lib (n = 17, 13.8% solids) or WM-ad lib (n = 20). All calves received colostrum ad libitum from their dam until d 3 of age. From d 4 to 27, calves were fed according to their group regimen. From d 28 to 55, all calves received MR-res feeding and were then gradually weaned until d 69. We recorded body weight (until d 110) and feed intake (amount, metabolizable energy, and frequency of liquid feed intake until weaning). We estimated the profitability of the different feeding regimens, taking into account income from milk yield (trial 2) and feed costs during rearing. In trial 1, the calves from WM-ad lib and MR-ad lib had total metabolizable energy intakes 2.02- and 1.65-fold greater than the MR-res group during the first 4 wk of life. During this period, concentrate intake did not differ among groups, but tended to be greater in WM-ad lib than in MR-ad lib calves from d 28 to 69. The MR-res calves visited the automatic feeders more often than the ad libitum-fed groups during differential feeding, but 70% of the visits were unrewarded (<10% in the ad libitum-fed calves). When all calves were fed at the MR-res level, the average proportion of unrewarded visits was 65% in all groups. Average daily gain and body weight were greater among MR-ad lib and WM-ad lib calves than among MR-res animals during the first 4 wk of life, but not from d 1 to 110. In trial 2, age at first calving, dry matter intake, and body weight over the first 10 mo of lactation were not different among groups, nor was milk composition. Milk yields (305 d) were numerically but not statistically greater in the ad libitum-fed groups during the first lactation (+765 kg for WM-ad lib vs. MR-res; +612 kg for MR-ad lib vs. MR-res). Feeding WM-ad lib and MR-ad lib was 1.37- and 1.21-fold more costly than MR-res, respectively, but amounted to 18, 15, and 13% of the total estimated feed costs until first calving in WM-ad lib, MR-ad lib, and MR-res, respectively. Our study confirms that ad libitum feeding is an attractive measure for rearing dairy calves, both for animal welfare and-with the caveat of a small sample size in trial 2 that led to insufficient power-economic profit from milk.

Mother-to-Child HIV Transmission Factors in Exposed Children at University Hospital Center of Treichville (Abidjan, Cote d’Ivoire)

Background: The elimination of HIV transmission from mother to child is currently possible. Cote d’Ivoire, which has a 4.6% HIV prevalence among women, is one of 22 pilot countries for the elimination of mother-to-child transmission of HIV. Since 2015, Cote d’Ivoire has adopted new strategies according to the WHO B+ guidelines. Objective: To identify factors associated with mother-to-child HIV transmission in children born of seropositive mothers managed at Treichville university hospital. Material and methods: A case-control study was conducted in the obstetrics department at Treichville university hospital, between January 2013 and December 2015. It involved children born to mothers infected with HIV, whose first PCR (Polymerase Chain Reaction) result was available during this period. A standardized questionnaire on data related to exposed children and their mother was used. Factors associated with mother-to-child HIV transmission were investigated using logistic regression. Results: A total of 214 HIV-exposed children were included in the study with a sex ratio of 0.9. The majority of the children were born by vaginal route (52.8%) and received post-exposure prophylaxis (88.3%) and replacement feed (51.9%). Their mothers received antiretroviral therapy during pregnancy in 45.3% of the cases. The first PCR was performed at the sixth week of life in 52.3% of cases. The prevalence of HIV infection in exposed children was 7.5% (95% CI = 4.5% - 11.8%). In multivariate analysis, the absence of antiretroviral prophylaxis in children [aOR = 4.3, 95% (1.2 to 15.6), p = 0.03], the mixed feed [aOR = 3.8, 95% (1.1 - 13.1), p < 0.03], the failure to take antiretroviral regimen during pregnancy [aOR = 8.0, 95% CI (1.9 - 32.4), p < 0.003], were associated with mother-child HIV transmission. Conclusion: The mother-to-child HIV transmission rate remains high in our practice. Strategies to reduce situations that do not comply with current recommendations should be considered to prevent mother-to-child HIV transmission.

Infant Feeding Practice and Associated Factors among HIV Positive Mothers Attending ART Clinic in Governmental Health Institutions of Bahir Dar Town, Amhara Regional State, Ethiopia, 2017

Objective: This study aimed to assess infant feeding practice and associated factor among HIV positive mothers attending ART service in governmental health institutions of Bahirdar town, Ethiopia, 2017.Methods: Institution based cross-sectional study was conducted in 3 Health centers and 1 Hospital which provides ART service in Bahirdar town from March to April, 2017. A total of 230 mother-infant pairs attending ART were selected by systematic random sampling technique. Structured interview was used to gather data on feeding practices. The data were coded, entered, cleaned and analyzed by SPSS software version 23. Bivariate and multivariate models were run to assess any relationship between each independent variable and outcome variables. Crude and adjusted odds ratios were used to ascertain for any association between the dependent and predictor variables while significance was determined using 95% confidence intervals.Results: The majority 173 (75.2%) practiced exclusive breast feeding up to six months of age. 13.9% and 10.9% of mothers practiced exclusive replacement feeding and mixed feeding, respectively. In multiple logistic regressions, Attended postnatal care (AOR (95% CI: 6.69 (1.647-27.178))), Time of initiation of first breast feeding after delivery (AOR (95% CI: 13.94 (2.98-65.05))), awareness of mothers on mother to child transmission of HIV via breast feeding was significantly associated with infant feeding practice (AOR (95% CI: 0.004 (0.00-0.05))).Conclusion: The study revealed that majority of the mothers’ experienced exclusive breast feeding (75.2%), postnatal care, time of initiation of first breast feeding after delivery and knowledge of MTCT during breast feeding were independent predictors of infant feeding practice.

The Cost Implications of Not Exclusively Breast Feeding in Jamaica

Although breastfeeding is known to enhance nutritional wellbeing and overall health it is recognized that a tradeoff exists between benefits and costs when mothers decide to maintain breastfeeding. This study examined whether the financial cost of not breastfeeding can be used as a powerful argument to promote breastfeeding. The prices of fresh milk, powdered milk and commercial formula were collected from popular supermarkets across four parishes in Jamaica. These prices were used to calculate the cost of replacement feeding for mothers who were partially and not breastfeeding during the first six months. Results show that households were spending between J$10,500 and J$73,000 on breast milk substitutes. For low income families this utilizes 14% to 65% of their salaries. The paper discusses the educational, workplace policy and food security implications and concludes that the financial benefits are profound.

Exclusive Breast Feeding Status and its Determinant among HIV Positive Women in West Showa Zone Oromia Region Ethiopia

Introduction: During the first six months of their life replacement feeding is recommended for infants born from HIV positive women under the condition of acceptable, feasible, affordable, sustainable and safe. Where this is not achievable, exclusive breastfeeding (EBF) is suggested during the first six months of life. Objective: To assess the EBF practice of HIV positive women and its determinants with in a selected health facilities of West showa zone Oromia region. Methods: Institutional based cross-sectional study was carried out among HIV-positive women attending PMTCT service using structured questioners. Consecutive sampling technique was applied in order to interview women. Data was analyzed using SPSS version 16.0 and multiple variable logistic regressions were done to identify risk factors of Exclusive breast feeding. Result: The proportion of exclusive breast feeding was 23.98%. Majority (79.34%) of the study subjects knew that HIV can transmit from mother to child during breast feeding. Mothers who had secondary educational status were three times more likely to give exclusive breast feeding than those who had no formal education (OR, 3.04 95% CI=2.72, 6.52). Mothers with household income earned 500-1000 birr were 2 times more likely to practice EBF than who earned 2000 birr (OR, 2.11 95% CI=1.93, 3.50). Compared to government employee women those who have self employee were 3.5 times more likely to practice EBF (OR, 3.51 95% CI=1.65-6.37). Mothers who delivered by C/S were 2.01 times more likely to practice EBF than those delivered by SVD (OR, 2.01 95% CI=1.07-4.38). Conclusion: The study revealed important findings which affect the practice of exclusive breast feeding of HIV positive mothers. All concerned bodies involvement is necessarily on infant feeding counseling to bring behavioral change in within communities for the better life of newborns.

Effects of Feeding Milk Replacer Ad Libitum or in Restricted Amounts for the First Five Weeks of Life on the Growth, Metabolic Adaptation, and Immune Status of Newborn Calves.

The pre-weaning period is critical for calf health and growth, and intensive milk feeding programs may assist postnatal development by improving body growth and organ maturation. The aim of the present work was to study the effects of ad libitum milk replacer (MR) feeding on the growth, metabolic adaptation, health, and immune status of newborn calves. Twenty-eight newborn Holstein and Holstein x Charolais crossbred calves were fed ad libitum (ADLIB) or in restricted amounts (6 liters per day; RES) during the first five weeks of life. The MR intake in the ADLIB treatment was gradually reduced at weeks 6 and 7, and all calves then received 6 liters of MR per day until day 60. Blood samples were collected to measure the plasma concentrations of metabolites, insulin, insulin-like growth factor (IGF)-I and IGF binding proteins (IGFBP), immunoglobulins, and acute phase proteins. The expression of mRNA associated with both the somatotropic axis and gluconeogenic enzymes was measured in the liver on day 60. Intensive feeding improved MR intake and growth in ADLIB without influencing concentrate intake. Carcass weight, perirenal fat, and muscle mass were greater in ADLIB. Plasma concentrations of glucose, triglycerides, insulin, and IGF-I were greater, whereas plasma concentrations of β-hydroxybutyrate, total protein, albumin, urea, IGFBP-2 and -4, and fibrinogen were lower at distinct time points in ADLIB. The hepatic mRNA expression of cytosolic phosphoenolpyruvate carboxykinase was greater in ADLIB. Most metabolic and endocrine differences occurred during the MR feeding period, but a slightly greater concentrate intake was associated with increased plasma IGF-I and insulin at the end of the study. The immune and health status of the calves were not affected by MR feeding. However, increased plasma fibrinogen in the RES group suggested differences in the acute phase response.

Het geven van vaste voeding aan witvleeskalveren vermindert de uitscheiding van clostridia in de mest

Clostridium perfringens geassocieerde enterotoxemie is een belangrijke oorzaak van sterfte bij kalveren in intensieve opfoksystemen. Het doel van deze studie was om het effect van vaste voeding te beoordelen op de uitscheiding van C. perfringens in de mest bij witvleeskalveren. Twee verschillende testdiëten werden at random toegewezen aan tien holsteinfriesian-witvleeskalveren. De kalveren in groep 1 werden uitsluitend gevoed met melkpoeder, terwijl kalveren in groep 2 zowel melkpoeder als een maximum van 300g vaste voeding per voederbeurt kregen. De vaste voeding bestond uit 30% gerst, 30% mais, 30% tarwe en 10% gehakseld stro. Vervolgens werd het aantal clostridia in de mest bepaald. Kalveren die zowel melkpoeder als vaste voeding kregen, scheidden significant minder clostridia uit in de mest dan kalveren die uitsluitend met melkpoeder werden gevoed. Er moet nog verder onderzocht worden of het verschaffen van vaste voeding aan witvleeskalveren een preventief effect heeft op enterotoxemie.

Clinical trial on the effects of a free-access acidified milk replacer feeding program on the health and growth of dairy replacement heifers and veal calves

The objectives of this study were to evaluate the effects of free-access acidified milk replacer feeding on the pre- and postweaning health of dairy and veal calves. Individually housed calves were systematically assigned at birth to 1 of 2 feeding programs: free-access feeding (ad libitum) of acidified milk replacer (ACD, n=249) or traditional restricted feeding (3L fed twice daily) of milk replacer (RES, n=249). Calves were fed milk replacer containing 24% crude protein and 18% fat. Acidified milk replacer was prepared to a target pH between 4.0 and 4.5 using formic acid. Calves were weaned off milk replacer at approximately 6wk of age. Weaning occurred over 5d, and during this weaning period, ACD calves had access to milk replacer for 12h/d and RES calves were offered only one feeding of milk replacer (3 L) daily. Calves were monitored daily for signs of disease. Fecal consistency scores were assigned each week from birth until weaning. A subset of calves was systematically selected for fecal sampling at 3 time points between 7 and 27d of age. Fecal samples were analyzed for enterotoxigenic Escherichia coli F5, Cryptosporidium parvum, rotavirus, and coronavirus. Hip width, hip height, body length, heart girth, and body weight were measured at birth and weaning. Postweaning body weight measurements were collected from the heifers at approximately 8mo of age. Postweaning body weight and carcass grading information was collected from the veal calves at slaughter once a live weight between 300 and 350kg had been achieved. The odds of ACD calves being treated for a preweaning disease event tended to be lower than that of the RES calves (1.2 vs. 5.2%, respectively). Preweaning mortality, postweaning disease treatment, and postweaning mortality did not differ between feeding treatments. The ACD feeding treatment supported greater preweaning average daily gain (0.59 vs. 0.43kg/d) and structural growth than RES feeding. Postweaning average daily gain and carcass characteristics were similar for ACD and RES calves. These results indicate that free-access acidified milk replacer feeding tended to support improved health, and greater body weight gain and structural growth during the preweaning period; these effects did not persist in the postweaning period. The growth advantage observed before weaning in the ACD calves likely disappeared due to the weaning methods used.

Changes in the intestinal bacterial community, short-chain fatty acid profile, and intestinal development of preweaned Holstein calves. 2. Effects of gastrointestinal site and age.

The objective of this work was to assess the effects of age and gastrointestinal location (rumen vs. colon) on bacterial community diversity and composition, as well as short-chain fatty acid profiles of preruminant male Holstein calves on an intensive milk replacer feeding program. Thirty-two calves were fed at 2% of their body weight (dry matter basis) from d 10 until harvest. Sixteen calves were euthanized at 2wk and another 16 at 4wk of age to collect digesta samples from the rumen and colon. The rumen and colon bacterial communities of preruminant calves showed a similar degree of diversity (i.e., Shannon index) whereas composition differed considerably. The colonic bacterial population was characterized by dominance of lactic acid bacteria such as Lactobacillus, Streptococcus, Enterococcus, and Bifidobacterium. In addition, colonic short-chain fatty acid and lactic acid concentrations were between 50 and 850% higher than in the rumen, indicating greater fermentative activity in the colon. On the other hand, in the rumen, no genus over-dominated and more variation was present among calves. Because of an active reticular groove and low starter grain intake during the first 1 to 3wk of life, ruminal fermentation may not contribute to significant metabolizable energy supply until after 4wk of life in intensively fed calves. Until then, calf hindgut fermentation, characterized by high abundance of lactic acid bacteria along with increased lactate and butyrate concentrations, could be beneficial for intestinal health and survival of the calf during the first weeks of life.