Uzi Moallem

• Doctor of Philosophy
• Research Scientist at Agricultural Research Organization ARO

We examined the effects of a supplement of plant polyphenols extracts of green tea, capsicum and fenugreek, and electrolytes [(Na+, K+), AXT; Axion ThermoPlus, CCPA, France] during summer heat load on production, welfare, and oxidative stress proteins in adipose tissue (AT) of dairy cows. Forty-two multiparous mid-lactation cows were divided into 3...

In sheep, ~30% of fetuses do not survive till parturition, and 17.7% of the multifetal pregnancies experience partial litter loss (PLL). In humans, multifetal pregnancies are associated with a higher risk of perinatal mortality. Therefore, the objectives were to examine the association between partial litter loss, fetal sex, dam’s metabolic and phy...

Metabolic disorders are often linked to alterations in insulin signaling. Omega-3 (n-3) fatty acids modulate immunometabolic responses; thus, we examined the effects of peripartum n-3 on systemic and adipose tissue (AT)-specific insulin sensitivity, immune function, and the endocannabinoid system (ECS) in dairy cows. Cows were supplemented peripart...

Negative energy balance (EB) postpartum is associated with adverse outcomes in dairy cows; therefore, non-invasive biomarkers to measure EB are of particular interest. We determined whether specific metabolites, oxidative stress indicators, enzyme activity, and fatty acid (FA) profiles in milk can serve as indicators of negative EB. Forty-two multi...

The form of a lipid supplement, its degree of saturation, and its fatty acid (FA) profile greatly influence digestibility and cow productive response. The objective in this study was to examine the effect of fat supplements that differ in their form or FA profile on nutrient digestibility and cow performance. Forty-two mid-lactation cows (128 ± 53...

Simple Summary Exposure to artificial white light at night (LAN) disrupts circadian rhythms, yet many dairy cows continue to be exposed to LAN for historical and practical reasons. We explored the effect of whole-night illumination, using white light-emitting diode (LED) bulbs, on the production and composition of milk collected during the day (day...

Because progesterone (P4) is essential for pregnancy establishment and maintenance, we investigated the effect of increased concentrations of P4 on embryonic attachment and concentrations of pregnancy-associated glycoproteins (PAG). Additionally, we investigated the relationships among luteal regression, pregnancy loss, and PAG concentrations in co...

Background: Dietary supplementation of omega-3 fatty acids can reduce the activation of the endocannabinoid system (ECS) by decreasing the availability of arachidonic acid, thus lowering endocannabinoids (eCBs) levels. The ECS is a modulator of energy metabolism, stress response and inflammation in mammals, yet there is little information on the r...

Wastewater from dairy farms has become a major environmental and economical concern. Sodium residue in treated and untreated wastewater from dairy farms used for irrigation can lead to soil and groundwater salinization, with the risk of soil degradation. We examined the effect of reducing sodium fed to mid to late lactating cows from 0.61% (high so...

Simple Summary Calcium salts of fatty acids from palm oil represent a very common supplement in dairy cows’ diets. The present results show that including up to 3.9% of CS-PFA in lactating cow rations with low fiber content did not affect milk and fat yields, decreased protein percentages and yields, reduced rumen fermentation, and decreased the to...

The impact of omega-3 nutritional manipulation on semen cryosurvival and quality post thawing is controversial. Our aim was to examine how feeding bulls with omega-3 supplementation from different sources affects the spermatozoa quality parameters. Fifteen Israeli Holstein bulls were fed for 13 weeks with a standard ration top-dressed with encapsul...

Background Dietary supplementation of omega-3 fatty acids can reduce the activation of the endocannabinoid system (ECS) by decreasing the availability of arachidonic acid, thus lowering endocannabinoids (eCBs) levels. The ECS is a modulator of energy metabolism, stress response and inflammation in mammals, yet there is little information on the rol...

Environmental heat load (HL) adversely affects the performance of dairy cows. The endocannabinoid system (ECS) regulates metabolism and the stress response, thus we hypothesized that HL may affect the ECS of dairy cows. Our objective was to determine the levels of endocannabinoids (eCBs) and gene and protein expressions of the ECS components in adi...

Fatty acid levels vary between day and night milking. Many dairy cows are kept under whole light at night (LAN) illumination using a white light-emitting diode (W-LED) suspected of disrupting circadian rhythms. We investigated the effect of W-LED LAN and same lux level red LED (R-LED) LAN, which is known not to disrupt circadian rhythms in other ma...

This article contains raw and processed data related to research published by Kra et al. [1]. There is a scarce knowledge on the proteome of peripheral blood mononuclear cells (PBMC) during the transition period in dairy cows. In human research, proteomics PBMC is used in order to gain insight into inflammatory diseases and syndromes. Dietary fats,...

This article contains raw and processed data related to research published by Swartz et al. [1]. We present proteomics data from liver of postpartum dairy cows that were obtained by liquid chromatography-mass spectrometry following protein extraction. Differential abundance between liver of cows experiencing either negative energy balance (NEB, n=6...

We examined the effects of dietary n-3 fatty acids on the proteome of peripheral blood mononuclear cells (PBMC) in transition dairy cows. Forty-two dry cows were divided into three groups supplemented with: saturated fat (CTL); flaxseed oil (FLX); or fish oil (FO). PBMC were collected from five cows per group at week 1 postpartum for proteomic anal...

Negative energy balance (NEB) is associated with metabolic disorders in early lactation dairy cows. Therefore, our objective was to characterize the liver proteome in cows experiencing either NEB or positive energy balance (PEB). Forty-two multiparous Holstein dairy cows were milked either 2 or 3 times daily for the first 30 days in milk (DIM) to a...

Fatty liver is an abnormal metabolic condition of excess intrahepatic fat. This condition, referred to as hepatic steatosis, is tightly associated with chronic liver disease and systemic metabolic morbidity. The most prevalent form in humans, i.e., nonalcoholic fatty liver disease, generally develops due to overnutrition and sedentary lifestyle and...

Fatty liver represents a significant metabolic pathology of excess intrahepatic fat in domestic animals and humans. Quantification of hepatic-fat content is therefore essential for diagnosis and investigation of liver and metabolic disease. However, the reproducibility of hepatic steatosis analysis is often low due to subjective and technical facto...

Total mixed ration (TMR) quality depends on feed levels and values, and appropriate diet formulation, but also on diet preparation practice. We examined the accuracy and homogeneity of rations, as affected by the machinery used for TMR preparation, and their effects on dairy cow performance. Multiparous Israeli-Holstein cows (n = 216) were stratifi...

Among the long-chain fatty acids (FA), the omega-3 (n-3) FA have the most potent immunomodulatory activities. In the present large-scale study, we tested the effects of supplementation of α-linolenic acid (ALA) from flaxseed commenced at the dry period on milk yield, health and fertility of dairy cows. Cows in a large commercial dairy farm were ran...

Feed is usually the costliest input in lactating cow's farms. Therefore, the developing of methods for a better adjustment of feed intake to cow's energetic needs in order to improve efficiency is desired. The aim of this study was to improve feed efficiency of low-efficient (LE) cows through a moderate increase in diet forage-to-concentrate ratio....

Pregnancy toxemia is the most frequent metabolic disorder of ewes in late pregnancy. Although propylene glycol (PG) and glycerol (GLY) are common glucogenic supplements for treating pregnancy toxemia in ewes, the relative benefit of these 2 supplements is not entirely clear. Therefore, the objectives of the present study were to determine the chang...

We investigated the effects of seasonal heat stress and the degree of body weight (BW) loss postpartum (PP) on immune and inflammatory markers in transition dairy cows. Blood sampled twice weekly during the transition period (3 wk prepartum to 3 wk PP) from 12 peripartum Holstein cows in summer and 12 in winter was analyzed for plasma nonesterified...

Hepatic steatosis is strongly associated with chronic liver disease and systemic metabolic disorder. Adipose lipolysis is a recognized principal source of intrahepatic fat in various metabolic disorders, including non-alcoholic fatty liver disease. We hypothesized that, in the premorbid state, hepatic de novo lipogenesis (DNL) driven by excess carb...

Intensive reproductive management in dairy herds is mostly based on AI using high-merit bulls. Therefore, semen quality of bulls is of high importance. An association between semen quality and fatty acid content in feed has been suggested. Accordingly, the aim of this study was to examine the effect of omega-3 supplementation on sperm traits and fe...

The two most popular rumen-protected fatty acid supplements in dairy cow rations are calcium salts of palm oil fatty acid calcium salts of palm oil fatty acid ( CSFA ) and prilled saturated fatty acids ( SFAs ). The objectives of this study were to determine the effects of supplementing SFA in the form of triglycerides ( TSFA ), as compared to CSFA...

Simple Summary Propylene glycol (PG) and glycerol are common energy substances used to supplement the feed of transitioning ruminants in order to minimize the development of metabolic disorders related to energy deficiency. Their effects on the energetic status of the animal have been, thus far, studied mostly by oral administration, which exposes...

Reducing milk production during early lactation might be of interest to improve the energy balance (EB) of high-yielding dairy cows. Therefore, the objective of this study was to determine how reducing the milking frequency (MF) of high-yielding dairy cows from thrice to twice a day during the first 30 d in milk (DIM) affects yields, intake, effici...

The aim of this study was to reduce voluntary dry matter intake (DMI) to increase feeding efficiency of preclassified inefficient (INE) dairy cows through restricted feeding. We studied the effects of dietary restriction on eating behavior, milk and energy-corrected milk (ECM) production, in vivo digestibility, energy balance, and measures of feed...

Adipose tissue (AT) plays a major role in metabolic adaptations in postpartum (PP) dairy cows. The endocannabinoid (eCB) system is a key regulator of metabolism and energy homeostasis; however, information about this system in ruminants is scarce. Therefore, this work aimed to assess the eCB system in subcutaneous AT, and to determine its relation...

Raw data of proteomic analysis. AT samples from high-weight loss (HWL, n = 5) or low-weight loss (LWL, n = 5) cows, based on the percentage of BW loss between week 1 and 5 postpartum, were analyzed by proteomic analysis at 14 d prepartum, 4 and 30 d PP. (XLSX)

Venn diagram of the top 25 canonical pathways in AT at 14 d prepartum, 4 d and 30 d postpartum according to the differentially abundant proteins in HWL and LWL dairy cows. AT samples from high-weight loss (HWL, n = 5) or low-weight loss (LWL, n = 5) cows, based on the percentage of BW loss between week 1 and 5 postpartum, were analyzed by proteomic...

Protein expression of CB1 and FAAH in ATs collected at 14 d prepartum and 4 d PP from HWL and LWL cows. Cows were categorized as high-weight loss (HWL, n = 9) or low-weight loss (LWL, n = 9) based on the percentage of BW loss between week 1 and 5 postpartum. The protein abundances of CB1 (A) and FAAH (B) were assessed by Western blotting analysis a...

Uncropped immunoblots of PLIN, Actin, MGLL, CB1, and FAAH in ATs collected at 14 d prepartum and 4 d PP from HWL and LWL cows. Cows were categorized as high-weight loss (HWL, n = 9) or low-weight loss (LWL, n = 9) based on the percentage of BW loss between week 1 and 5 postpartum. (TIF)

Mammals can synthesize all of the fatty acids (FA) necessary for proper health and functioning with the exception of FA in the n-3 (omega-3) and n-6 (omega-6) families of polyunsaturated fatty acids (PUFA), which should be supplied in the diet. The PUFA are the predominant type of lipid in dairy cattle diets; however, common feedstuffs are rich in...

The varied and elusive etiology of repeat breeding (RB) in dairy cows necessitates evaluation of oocytes and follicles, which have not previously been assessed together. Accordingly, we evaluated characteristics of preovulatory follicles and the competence of oocytes in control (CTL) and RB cows. The estrous cycles of 35 cows (18 CTL and 17 RB) wer...

Objective: Galactomannans derived from fenugreek confer known health benefits; however, there is little information regarding health benefits of citrus pectin (CP) and its association with gut microbiome metabolites. The aim of this study was to examine links between galactomannan and CP consumption, microbiota development, and glucose metabolism....

Great variation exists among cows in the magnitude of tissue mobilization during early lactation; however, it is not known whether this is an intrinsic trait. Our aims were (1) to test whether the degree of body weight (BW) loss is consistent within cows across lactations by examining daily BW records of 4 to 5 consecutive lactations and their rela...

Metabolizable energy requirements rise dramatically at late gestation in ewes bearing multiple-fetuses; consequently, prolific ewes may suffer pregnancy toxemia and fetal intrauterine growth restriction. The present objectives of this study were to examine in ewes bearing ≥ 2 fetuses, the effects of dietary supplementation with a molasses-based pro...

This article contains raw and processed data related to research published in Zachut et al. (2016) [1]. Proteomics data from preovulatory follicles in cows was obtained by liquid chromatography-mass spectrometry following protein extraction. Differential expression between controls and less fertile cows (LFC) was quantified using MS1 intensity base...

Significance: High yielding dairy cows suffer from infertility that leads to major economic losses worldwide. In Israel, about 30% of dairy cows fail to conceive following ≥4 inseminations. The etiology of this low fertility is multifactorial and remains a serious challenge. Follicular fluid proteome can provide indication to follicular quality, y...

The objectives were to examine the gross and marginal production efficiencies in high-yielding dairy cows and the future consequences on dairy industry profitability. Data from 2 experiments were used in across-treatments analysis (n = 82 mid-lactation multiparous Israeli-Holstein dairy cows). Milk yields, body weights (BW), and dry matter intakes...

Repeat breeder (RB) cows were compared with normal (CTRL) ones with respect to: behavioral estrus intensity, endocrine patterns and concentrations of plasma estradiol, progesterone and LH around estrus, and ovulation timing. A total of 27 and 31 cycles in 12 RB and 18 CTRL cows, respectively, were synchronized by means of the Ovsynch protocol follo...

The mechanism underlying the shift in milk-fat-globule (MFG) mean diameter upon changing the concentrate-to-forage ratio in dairy cow rations was investigated. Cows were fed high-concentrate low-forage (HCLF) or high-forage low-concentrate (LCHF) rations for 4weeks. Mean diameter of MFG, determined in raw whole milk, was 0.4μm larger in the LCHF-fe...

Prostaglandin endoperoxide synthase 2 (PTGS2), tumor necrosis factor-alpha-induced protein-6 (TNFAIP6), pentraxin-3 (PTX3), epidermal growth factor like factors: amphiregulin (AREG) and epiregulin (EREG) are essential for successful ovulation. We compared here the induction of these ovulatory genes in bovine granulosa cells (GCs) in vivo (after LH...

We examined the effects of concentrate-to-forage ratio in dairy cow rations on milk-fat composition, with a specific focus on the structure of milk fat globules (MFG). Twenty-four Holstein cows, 153 d in milk, were assigned to 2 dietary treatments in a crossover design study. Treatments were (1) high-concentrate (65%), low-forage (35%; HCLF) diet a...

Abstract Text: Due to the rise in grain price, there is an increased use of fat in rations of dairy cows in Israel; however, the effects of high rates have never been examined in the Israeli rations. Therefore, the objectives were to determine the effects of increasing rate of calcium soap of fatty acids (CSFA) on yields, efficiency and digestibili...

Abstract Text: The objective was to test whether Saccharomyces cerevisiae fermentation product (XP, Diamond V, Cedar Rapids, IA) could compensate for lower energy density in diets by increasing digestive efficiency. Forty-two multiparous Israeli-Holstein dairy cows were divided into 2 treatment groups according to milk production, parity, DIM and B...

Thirty-five lactating dairy cows throughout weeks of lactation (WOL) 16 to 30 were used to determine optimal time needed for reliable measurement of performance variables, and to classify the cows into high-, medium-, and low-efficiency groups. Individual performance variables [body weight (BW), dry matter intake (DMI), and milk production] were me...

This study presents a computer vision tool to automatically estimate body condition scoring (BCS). BCS indicates energy reserves of dairy cows for estimating their fatness or thinness according to a 5-point scale. Digital Images of eighty seven cows were collected in an Israeli research dairy farm using a Nikon DSLR camera located at the entrance o...

Body condition evaluation is a common tool to assess energy reserves of dairy cows and to estimate their fatness or thinness. This study presents a computer-vision tool that automatically estimates cow's body condition score. Top-view images of 151 cows were collected on an Israeli research dairy farm using a digital still camera located at the ent...

The objectives were to determine the differential incorporation of various omega-3 (n-3) fatty acids (FAs) supplemented to dairy cows into ovarian compartments, and assess the effects on in vitro fertilization (IVF). Forty-two 256-day-pregnant cows were supplemented with encapsulated fats, in treatments designated as: (i) SFA - saturated fat at 240...

The periparturient period in dairy cows is associated with alterations in insulin action in peripheral tissues; however, the molecular mechanism underlying this process is not completely understood. The objective was to examine the response to a glucose tolerance test (GTT) and to analyze insulin signaling in liver and adipose tissues in pre- and p...

During diet-induced milk fat depression (MFD), the short and medium-chain fatty acids (SMCFA), which are synthesized de novo in the mammary gland, are reduced to a much greater extent than the long-chain fatty acids (LCFA) that originate from the circulation. Our hypothesis was that increased availability of SMCFA might rescue conjugated linoleic a...

A protocol based on small doses of FSH was examined for the induction of double or triple (multiple) ovulations in cattle. Ovulation rate, follicular characteristics and luteal responses were determined. In Exp. 1, 3 groups of estrus-synchronized, cyclic Holstein heifers were treated once daily, on d 3 to 6 of the cycle, with a FSH product (Folltro...

The objectives of the present study were to evaluate the transfer efficiency of α-linolenic acid (ALA) from the abomasum into milk fat, its interaction with milk fat content and yield, and the relationship between ALA and C16:0 in milk fat. Three rumen-fistulated multiparous Holstein cows at midlactation were used in a 3×3 Latin square design. Trea...

The objectives were to determine the effects of cooling of high-yielding dairy cows under a hot and humid climate on intake, milk yield, rumination time, and welfare parameters. Forty-two multiparous Israeli Holstein dairy cows were divided into 2 treatment groups and were housed in an open barn divided into 2 pens. The groups were subjected to dif...

Ruminal wall metabolism was studied in nonlactating heifers by altering the carbohydrate (CHO) digestion site between rumen and intestine. The CHO digestion site was estimated from in situ and total-tract digestibility of control (CONT) diets and diets supplemented with corn (CRN), barley (BARL), or soy hulls (SOYH). Ruminal epithelial metabolism r...

The passage of long-chain fatty acids (FA) through the placenta in ruminants is limited. However, essential long-chain polyunsaturated FA, and especially n-3 FA, are crucial for normal development of the bovine fetus; therefore, uptake of these FA by the embryo must occur during pregnancy. The objectives of the present study were to examine the eff...

Ewes bearing more than 1 fetus are more susceptible to pregnancy toxemia than those with a single fetus. Crossbreeding programs in Israel increased the occurrences of ewes bearing more than 2 fetuses; therefore, the aim was to assess the exacerbation in the metabolic status of ewes pregnant with several fetuses. Fifty ewes, genetically developed to...

This study compared immediate and carryover effects of mastitis induced by Gram-negative endotoxin (E. coli LPS) and Gram-positive exosecretions (Staph. aureus ex.) on preovulatory follicle function. Synchronized, uninfected cyclic lactating Holstein cows were treated with PGF(2α) on day 6 of the cycle and 36 h later, a dose of either E. coli LPS (...

The objective of this study was to examine the incorporation of dietary n-3 fatty acids (FAs) into ovarian compartments and the effects on hormonal and behavioral patterns around estrus. Multiparous 256-day pregnant cows were fed either a standard diet both prepartum and postpartum (PP) (control; n=22) or supplemented with extruded flaxseed (E-FLAX...

Chronic, subclinical intramammary infection depresses fertility. We previously found that 30% of subclinical mastitic cows exhibit delayed ovulation, low circulating estradiol levels, and delayed luteinizing hormone surge. We examined the function of preovulatory follicles of cows experiencing subclinical mastitis or a past event of acute clinical...

The objectives were to examine the effect of high dietary crude protein on characteristics of preovulatory follicles in dairy heifers. Eight Israeli-Holstein heifers, 4 fitted with rumen fistula and 4 intact, were assigned to 1 of 3 treatments in a replicated (n=2) 4 × 3 incomplete Latin square design with 39-d periods. Treatments were: low (6.0%;...

The objective of this study was to determine the effects of feeding an increased amount of extruded flaxseed with high proportions of n-3 fatty acids (FA) to transition dairy cows on performance, energy balance, and FA composition in plasma, adipose tissue, and milk fat. Multiparous Israeli-Holstein dry cows (n = 44) at 256 d of pregnancy were assi...

Multiparous Israeli-Holstein cows (n=42) averaging 158 d in milk and 621 kg of body weight were used to investigate the effects of energy source (fat or concentrate) on production, rumination time, energy balance, metabolic heat production, and efficiency under hot and humid conditions. Cows were assigned to 3 diet treatment groups: a lactating-cow...

Our objectives were to determine the effects of rapid growth rate during the preweaning period and prepubertal protein supplementation on long-term growth pattern and milk production during the first lactation. Forty-six Israeli Holstein heifer calves were fed either milk replacer (MR) or whole milk (WM) from 4 to 60 d age. Calves had free access t...

Several processes have been suggested to protect lipids from bioactivity of the rumen microorganisms. The majority of experiments with conjugated linoleic acid (CLA) were conducted using calcium salts of CLA. The objectives of this study were to determine the effects of encapsulated CLA (E-CLA) that was supplemented during days 21 to 100 post partu...

The objectives were to determine the incorporation of dietary encapsulated fats differing in n-6:n-3 ratio into milk fat, plasma, and various ovarian compartments and to examine the effects on ovarian follicular status, preovulatory follicle characteristics, and oocyte quality. Twenty-four multiparous Israeli Holstein cows, averaging 114 d in milk,...

The objectives of this study were to determine the effects of extruded flaxseed supplementation to high-yielding dairy cows on milk yield and fatty acid profile. One-hundred Israeli-Holstein dairy cows averaging 150 days in milk (DIM) were stratified into two treatment groups on the basis of milk production, DIM and parity. The treatments were: (1)...

The current study examined the effects of live yeast (LY) supplementation to dairy cows during the summer season on milk production, feed efficiency and ration digestibility. Forty-two dairy cows (14 primiparous and 28 multiparous) were fed either a control lactating diet or supplemented with 1 g of LY (Saccharomyces cerevisiae, Biosaf, Lesaffre) p...

Mastitis is the most common disease affecting dairy herds. The influence of mastitis on the oocyte and on early embryonic development is unclear. The aim of the present study was to examine the effects of endotoxin on oocyte developmental competence. Six lactating Holstein cows were synchronized using the Ovsynch protocol. PGF2α was administered on...

Follicular development, follicular rupture, and corpus luteum (CL) formation are accompanied by extensive tissue remodeling. We examined whether heparanase (HPSE), which cleaves heparan sulfate glycosaminoglycans, is induced during these processes. Prostaglandin F2α injection, which initiated luteolysis and the development of a preovulatory follicl...

Dietary unsaturated fatty acids (UFAs) have been implicated in several reproductive processes in dairy cows through a variety of mechanisms. This study examined the effects of periparturient supplementation of rumen bypass fats low or high in proportion of UFAs (oleic and linoleic) on preovulatory follicle characteristics. Forty-two 256-day pregnan...

Dry multiparous cows were used to investigate the effects on intake, production, and metabolism of either a supplement containing 55% dry propylene glycol (PGLY), a prilled fat supplement (PrFA) containing a low proportion of unsaturated fatty acids (FA), or calcium soaps of FA supplement (CaLFA) containing a high proportion of unsaturated FA. Fift...

Eighty multiparous cows were used to test the effects of feeding a supplement containing 55% dry propylene glycol (PGLY), prilled fat (PrFA) containing a low proportion of unsaturated fatty acids (FA), or calcium soaps of long-chain FA (CaLFA) containing a high proportion of unsaturated FA on energy balance (EB), blood metabolites, and early postpa...

Summer heat stress (HS) is a major factor in decreased reproductive performance in high-producing dairy cattle, possibly by affecting the steroidogenic capacity of ovarian follicles and ovarian follicular dynamics. In the present study, mRNA expression of cholesterol receptors was determined in bovine ovarian cells. Two endocytotic receptors (very-...

The suitability of a statistical model for describing within-day feeding behavior, and potential relationships between model parameters and commonly measured experimental variables were examined. Forty multiparous, midlactation Holstein cows were fed using a real-time control system to record the date of each visit to a feeder, entrance time, exit...

Forty Israeli-Holstein 5-d-old calves were used to determine the effect of increasing calf body weight (BW) and skeletal size during the nursing period on age and skeletal size at puberty and on skeletal size and performance during first lactation. The calves were randomly allotted to 2 experimental groups as follows: milk replacer (MR) [calves wer...