Body Reserves Research Articles

Resource allocation effects on the timing of reproduction in an avian habitat specialist

AbstractVariation in nutrient allocation can influence the timing of breeding and ultimately reproductive output. Time and space constraints might exist, however, if fewer food resources are available to meet the costs of reproduction early during the reproductive season. Here, for the first time, we test whether nutrient‐allocation strategies for reproduction in a shrub‐dependent avian species differ with timing of breeding in different ecoregions: a high‐elevation landscape, containing spatially complex vegetation (Rocky Mountains) vs. a low‐elevation, more homogenous landscape (Great Plains). We analyzed data collected from radio‐telemetry and stable isotopes to assess the degree to which endogenous (body) reserves are used for reproduction and whether variation in allocation strategies was associated with time of year, ecoregion, habitat quality (including sagebrush type and plant greenness), or maternal characteristics. Using a Bayesian statistical framework, we found that females relied on a similar amount of endogenous reserves for reproduction in first nesting and renesting attempts. Additionally, endogenous contributions declined more rapidly throughout the nesting season in the Rocky Mountains than in the Great Plains. Individuals in high‐ and intermediate‐elevation sagebrush types in the Rocky Mountains used similar amounts of endogenous reserves, whereas females nesting in low‐elevation sagebrush used less. Females nesting at intermediate elevations, which experience the greatest flush of new green vegetation during the nesting season, switched their reliance from endogenous‐to‐exogenous sources for reproduction as green vegetation became available during spring. Our study highlights adaptations of a nutrient‐allocation strategy across areas with varying levels of resources in time and space in a habitat specialist bird. Nutrient allocation by individuals residing in high‐elevation areas favors a strategy that mainly uses nutrients gained from wintering habitats, whereas individuals residing in low‐elevation areas mainly use exogenous sources for reproduction.

Probiotic effect on reserve mobilization in late stage pregnancy in goats

This study was carried out to evaluate a probiotic effect on the mobilisation of body reserves in goats towards the end of gestation by measuring ketone body production in blood and calculating the body condition score (BCS). Ketone body production was monitored by measuring the betahydroxybutyrate BHB levels in the blood using a portable kit (PRECISION XTRA Blood ketone test). The results revealed that the use of the probiotic SYMBIOVEBA® (association of Saccharomyces cervicae and Lactobacillus) did not decrease the formation of blood BHB in goats, and therefore did not decrease mobilization of the body reserves of goats in late pregnancy.

Reproductive characteristics, diet composition and fat reserves of nose-horned vipers (Vipera ammodytes)

Long-term ecological studies are usually both time-consuming and costly, particularly when conducted on species with low detectability, such as vipers. An alternative, non-expensive method for obtaining detailed information about numerous important ecological traits, e.g. size at maturity, reproductive output, diet composition and amount of body reserves, are dissections of museum specimens. We dissected 237 museum specimens (125 males and 112 females of all age classes) of the nose-horned vipers Vipera ammodytes from the central and western regions of the Balkan Peninsula. Their reproductive and digestive systems were examined, and fat stores estimated. Relative testes volumes were significantly higher in adults than in subadults. Also, we found seasonal variation of testes volumes in adult males. Females became mature at around 43.8 cm snout-to-vent length (SVL); 38.1 % of adult females were pregnant (i.e. had developed eggs/embryos, suggesting bi- or even triennial reproduction frequency). The average number of developed eggs/embryos was 9.1 (range 5–17). As expected, there was a positive correlation between maternal body size (SVL) and the number of embryos. The nose-horned vipers fed predominately on lizards (64.7 %) and mammals (31.9 %); only a few remains of different prey were found (birds, snakes and centipedes). Analyses of inter-sexual differences showed that males more frequently consumed lizards than mammals, while in females both types of prey were equally present. A subtle ontogenetic change in diet was recorded, with a shift from lizards towards mammals. Adult individuals had more fat reserves than subadults, but there were no inter-sexual differences, and gravid females had similar amounts of fat reserves as non-gravid individuals. The data about reproductive output and dietary specialisation demonstrate the vulnerability of the species, generally regarded as “quite common” and non-threatened. This study might help in the establishment of future conservation studies, and management of the impacts of anthropogenic factors on populations of V. ammodytes in the central and western Balkans.

Effect of feed restriction on dairy cow milk production: a review.

In the dairy cow, negative energy balance affects milk yield and composition as well as animal health. Studying the effects of negative energy balance on dairy cow milk production is thus essential. Feed restriction (FR) experiments attempting to reproduce negative energy balance by reducing the quantity or quality of the diet were conducted in order to better describe the animal physiology changes. The study of FR is also of interest since with climate change issues, cows may be increasingly faced with periods of drought leading to a shortage of forages. The aim of this article is to review the effects of FR during lactation in dairy cows to obtain a better understanding of metabolism changes and how it affects mammary gland activity and milk production and composition. A total of 41 papers studying FR in lactating cows were used to investigate physiological changes induced by these protocols. FR protocols affect the entire animal metabolism as indicated by changes in blood metabolites such as a decrease in glucose concentration and an increase in non-esterified fatty acid or β-hydroxybutyrate concentrations; hormonal regulations such as a decrease in insulin and insulin-like growth factor I or an increase in growth hormone concentrations. These variations indicated a mobilization of body reserve in most studies. FR also affects mammary gland activity through changes in gene expression and could affect mammary cell turnover through cell apoptosis, cell proliferation, and exfoliation of mammary epithelial cells into milk. Because of modifications of the mammary gland and general metabolism, FR decreases milk production and can affect milk composition with decreased lactose and protein concentrations and increased fat concentration. These effects, however, can vary widely depending on the type of restriction, its duration and intensity, or the stage of lactation in which it takes place. Finally, to avoid yield loss and metabolic disorders, it is important to identify reliable biomarkers to monitor energy balance.

Feeding diets varying in starch concentration supplemented with palmitic acid or stearic acid: Effects on performance, milk fatty acid profile, and metabolic parameters of postpartum dairy cows

The objective of this study was to investigate the effects of dietary fat supplement rich in palmitic acid or stearic acid on milk yield and composition, fatty acid profile, energy partitioning, and metabolic parameters of dairy cows fed low or high starch diets from d 1 to 28 of the postpartum period. Forty-four multiparous Holstein cows were used in a complete randomized block (based on parity, and previous 305-d milk yield); 2 × 2 arrangement with two dietary starch levels [high starch (HS); 260 g/kg of diet dry matter (DM) versus low starch (LS); 210 g/kg of diet DM] with either palmitic acid (PA) or stearic acid (SA) supplementation at the level of 15 g/kg of diet DM. A basal close-up diet (6.19 MJ/kg of diet DM, NEL; 200 g/kg starch) was fed to animals prior to calving. Regardless of the fatty acid (FA) type, cows fed HS diets had a higher dry matter and NEL intake, milk protein and lactose content, and a more positive energy balance than cows fed LS diets during the postpartum period. Compared with HS diets, LS diets reduced energy toward body reserves and maintenance as a fraction of the NEL intake. Although there was no main effect of PA or SA supplement on intake and energy balance, the effect of fat supplementation depended on dietary starch levels for milk yields and milk energy as a fraction of the NEL intake. Stearic acid increased milk yield in HS diets while PA tended to increase yield in LS diets. Supplementation of PA partitioned less energy toward milk (and more energy for maintenance) in HS diets than LS diets. Moreover, the C16:0 FA concentration in milk fat was higher, and the polyunsaturated FA (PUFA) and C18:1 cis-9 FA were lower in PA supplemented cows fed HS diets but not cows fed LS diets. High starch rations increased de novo FA concentrations in milk and decreased C18:0 and preformed FA concentrations compared with LS diets. Also, HS diets tended to have higher levels of insulin and lower levels of beta-hydroxybutyrate (BHBA) than LS diets. In conclusion, the HS diet was more beneficial to improving the energy balance (EB) of dairy cows than LS diets during the early postpartum period. Also, interactions between dietary starch levels and FA supplement for the variables measured in the current study (e.g. milk yield or FA profile) indicate that the response to fat supplements rich in specific FA differed on the basis of dietary starch concentrations.

Pre-breeding Diets in the Seahorse Hippocampus reidi: How Do They Affect Fatty Acid Profiles, Energetic Status and Histological Features in Newborn?

Seahorses (Hippocampus spp.) are exceptional marine species considering their reproductive patterns and other features. Due to the iconic characteristics of these fishes, aquarium trade, and research efforts have increased in the last years. Consequently, novel rearing techniques have been developed; however, there is a need for improvements on a series of issues, namely reproduction success enhancement. The tropical species Hippocampus reidi is the most traded seahorse but many aspects of breeding and its impact on the quality of neonates are still poorly understood. In the present study, we assessed the effects of two pre-breeding diets on newborn quality and viability considering biochemical characteristics, energetic status, and ultrastructural aspects of muscular tissue. During the whole pre-breeding season (5 months), the breeders were fed on one of the following diets: M0 (adult non-enriched Artemia) and M5 (adult non-enriched Artemia + mysidaceans). From the onset of the reproduction period, all breeders were fed for 6 months on diet M5. Breeding success and energetic status (ATP, total adenylic nucleotides, AEC, and NAD) of newborns resulted considerably enhanced in treatment M5. However, initial differences in neonates quality did not affect further newborn performance (survival and growth until day 7 after male’s pouch release) while gaining access to high-quality preys (copepods). Besides, morphological alterations in muscle tissue were not observed. The reproduction in the species followed a capital–income continuum pattern characterized by an initial mixed capital-income period (until 70–100 days since the onset of the breeding season) followed by an income breeding period with progressive exhaustion of body reserves, especially in M0-newborns. Interestingly, the effects of pre-breeding diets were also noticed in the second half of the breeding period. Our results seemed to indicate that the requirements in essential fatty acids in H. reidi are lower than in other seahorse species (e.g., Hippocampus guttulatus). Globally, the results achieved revealed that high-quality pre-breeding diets enhanced reproduction success and would likely result advantageous to improve newborn endurance in conditions of moderate starvation or sub-optimal feeding.

Within and between breeding-season changes in contaminant occurrence and body condition in the Antarctic breeding south polar skua

The Antarctic ecosystem represents a remote region far from point sources of pollution. Still, Antarctic marine predators, such as seabirds, are exposed to organohalogen contaminants (OHCs) which may induce adverse health effects. With increasing restrictions and regulations on OHCs, the levels and exposure are expected to decrease over time. We studied south polar skua (Catharacta maccormiciki), a top predator seabird, to compare OHC concentrations measured in whole blood from 2001/2002 and 2013/2014 in Dronning Maud Land. As a previous study found increasing organochlorine concentrations with sampling day during the 2001/2002 breeding season, suggesting dietary changes, we investigated if this increase was repeated in the 2013/2014 breeding season. In addition to organochlorines, we analyzed hydroxy-metabolites, brominated contaminants and per- and polyfluoroalkyl substances (PFAS) in 2013/2014, as well as dietary descriptors of stable isotopes of carbon and nitrogen, to assess potential changes in diet during breeding. Lipid normalized concentrations of individual OHCs were 63%, 87% and 105% higher for hexachlorobenzene (HCB), 1,1-dichloro-2,2-bis (p-chlorophenyl)ethylene (p,p'-DDE), and ∑Polychlorinated biphenyls (PCBs), respectively, in 2013/2014 compared to 2001/2002. South polar skuas males in 2013/2014 were in poorer body condition than in 2001/2002, and with higher pollutant levels. Poorer body condition may cause the remobilization of contaminants from stored body reserves, and continued exposure to legacy contaminants at overwintering areas may explain the unexpected higher OHC concentrations in 2013/2014 than 2001/2002. Concentrations of protein-associated PFAS increased with sampling day during the 2013/2014 breeding season, whereas the lipid-soluble chlorinated pesticides, PCBs and polybrominated diphenyl ether (PBDEs) showed no change. OHC occurrence was not correlated with stable isotopes. The PFAS biomagnification through the local food web at the colony should be investigated further.

PSIII-13 Effects of Saccharomyces Cerevisiae Fermentation Products on Lactating Sow Performance

Abstract Lactating sows (N=140, York x Landrace) were used to evaluate the effects of a liquid prototype (LIQP) and dry (XPC®; Diamond V) Saccharomyces cerevisiae feed additives on sow and litter performance. Sows were fed a common gestation diet (0.55% SID-Lysine) until d112 of pregnancy and then allotted to lactation treatments: 1) Control diet (CON; 1.00% SID-Lysine), 2) CON +15 mL of LIQP from d112 to weaning (LIQ), 3) CON +0.20% of XPC from d112 to weaning (DRY), and 4) DRY +15 mL of LIQP from d112 to d7 post-farrowing (D+L). The LIQP was given once daily using an oral dose gun and XPC was included in the feed. Immunoglobulin concentrations were estimated on colostrum samples using Brix refractometer and piglet d 1 serum immunocrit ratio and plasma IgA and IgG. Daily sow water intake and daily feed intake (DFI) from d112 of gestation to d7 post-farrowing and weekly feed intake (ADFI) were recorded. There were no treatment effects on sow BW, backfat, or loin depth (P >0.05) although sows from LIQ group had numerically smaller BW reductions compared to CON sows (4.9% vs 7.2%, P=0.19). LIQ sows had greater DFI and CON lower DFI during week 1 of lactation (P=0.04) as well as ADFI for weeks 2, 3, and overall lactation period (P< 0.01) with DRY and D+L sows being intermediate. Water intake, immunoglobulins, and litter performance did not differ among treatments (P >0.05) although pigs from LIQ sows, compared to CON, had numerically increased weaning (6.14 vs 5.82kg, P >0.05) and litter weights (63.2 vs 60.1kg, P >0.05). LIQ sows had 0.7 d reduced wean-to-estrus interval (P< 0.001) and tended to have greater conception rates (P=0.07). In conclusion, LIQ supplementation of lactating sows improves feed intake, allowing sows to keep body reserves, and have better subsequent rebreeding performance.

Nutrition and Food in the Reproduction of Cattle

At the beginning of the 1980s, a series of very profound changes were initiated in the milk cow nutrition approaches, as a consequence of the highest levels of production per cow that were reached by the productive systems of the northern hemisphere. Nutrition is defined as the series of processes through which an organism acquires and assimilates food to promote its growth and replace worn or damaged tissues. The nutrients are fundamental for the animals to carry out their different productive functions. When we consider the aspects that touch the field of nutrition of ruminants, we understand the importance of this group of animals of zootechnical interest, which are able to process plant components that are not consumed by other mammals, the structural carbohydrates (fiber). Ruminant comes from the word "rumen", which is the largest of the compartments in the stomach of four compartments of a bovine, sheep or goat. This structure is where microbial fermentation takes place. The ruminants, through evolutionary processes, developed life relationships with microorganisms which enabled them to use fiber as food, that is, they developed in some way their "food factory". They eat the forage to be transformed by the rumen's microbiota into substances that are the source of energy for the animal and for the microbial synthesis, the microbial cells are an excellent source of proteins for the animal. However, the processes that make the ruminal microbiota are, in a certain way, inefficient. Grass degradation produces volatile fatty acids, microbial protein and gases. Within these gases, some are environmental pollutants such as CO2, methane and nitrous oxide. Millions of bacteria, protozoa, and fungi live in the rumen and degrade parts of the plant rich in energy, making them digestible to the animal host. After the forage has been digested in the rumen and degraded to smaller parts, it can pass through the reticulum and omasum, which function as colanders that trap large pieces of material preventing them from reaching the abomasum, or "true stomach", where digestion continues. The nutritional concern for ruminants focuses on energy (ie, carbohydrates), protein, minerals, vitamins, and water. The energy (carbohydrates) is responsible for the functions of growth and maintenance of the animal, and the generation of heat. The protein makes the tissue grow and performs other vital functions. Other nutrients and minerals such as vitamin A and E, calcium, phosphorus, and selenium can be fed to "free choice" as a mineral supplement. Dairy cows of high productive potential (9000-12000 / liters / lactation) currently represent a real challenge for nutrition. For many years, there has been evidence of the impact of nutrition on the reproductive behavior of the bovine female. The main factor that affects reproduction is the undernourishment due to the scarcity and quality of the food. Subsequent research has shown that nutritional effects are exerted through complex interrelations between various aspects such as: content and use of body reserves, distribution of nutrients between different systems and organs and prioritization of the use of nutrients for various functions in addition to reproduction.

Associations between feed efficiency and aspects of lactation curves in primiparous Holstein dairy cattle

Genetic selection for improved feed efficiency in dairy cattle has received renewed attention over the last decade to address the needs of a growing global population. As milk yield is a critical component of feed efficiency metrics in dairy animals, our objective was to evaluate the associations between feed efficiency in primiparous Holstein cattle and parameters of a mathematical model describing individual lactation curves. The Dijkstra lactation curve model was fit to individual lactation records from 34 Holstein heifers with previously estimated measures of feed efficiency. We found that the optimal fit of the Dijkstra model was achieved using daily milk yield records up to 21 d in milk to capture the rise to peak milk yield and using monthly dairy herd improvement records for the remainder of lactation to accurately characterize lactation persistency. In the period of lactation before peak milk yield, improved feed efficiency was associated with a faster increase in daily milk yield over a shorter period of time at the expense of increased mobilization of body reserves; this serves to reinforce the concept that dairy cattle are primarily capital breeders versus income breeders. Feed efficiency in the period following peak lactation, as measured by gross feed efficiency, return over feed costs, and net energy efficiency of lactation, was positively associated with higher peak milk yield. The findings in early lactation suggest that estimates of feed efficiency could be improved by evaluating feed efficiency relative to conception, rather than parturition and lactation, to better account for the energy stored and released from body reserves in capital breeding.

Dietary Starch Concentration Affects Dairy Sheep and Goat Performances Differently during Mid-Lactation.

Simple SummaryIn order to favor milk production, this research suggests that the concentration of starch in the diet of dairy ewes in mid-lactation should be reduced, compared to early lactation, by introducing sources of highly digestible fiber. On the other hand, this type of diet is not adequate for dairy goats, which should maintain the use diets rich in starch, even in mid-lactation, to support milk yield, as well.Evolution of milk production, body reserves and blood metabolites and their relationships with dietary carbohydrates were compared in 30 Sarda dairy ewes and 26 Saanen dairy goats in mid-lactation. From 92 to 152 ± 11 days in milk (DIM), each species was allocated to two dietary treatments: high-starch (HS: 20.0% starch, on DM basis) and low-starch (LS: 7.8% starch, on DM basis) diets. In mid-lactating goats, the HS diet increased fat-corrected milk yield (FCM (3.5%); 2.65 vs. 2.53 kg/d; p = 0.019) and daily milk net energy (NEL; p = 0.025), compared to the LS diet. The body condition score (BCS) was not affected. In mid-lactating ewes, the LS diet increased FCM (6.5%) (1.47 vs. 1.36 kg/d; p = 0.008), and NEL (p = 0.008), compared to the HS diet. In addition, BCS was greater in HS than in LS ewes (3.53 vs. 3.38; p = 0.008). Goats had a higher growth hormone (GH) and lower insulin concentration than ewes (GH: 2.62 vs. 1.37 ng/mL; p = 0.04; insulin: 0.14 vs. 0.38 µg/L; p < 0.001 in goats and ewes, respectively). In conclusion, in mid-lactation, the two species responded differently to dietary carbohydrates, probably due to differences in the concentration of GH and insulin. The HS diet favored milk yield in goats and body reserve accumulation in ewes. In ewes, the partial replacement of starch with highly digestible fiber increased energy partitioning in favor of milk production.

Sow-related factors affecting the postweaning feed intake in Landrace × Large White females.

During the weaning-to-estrus interval (WEI), a high feeding level is usually offered to recover losses due to lactational catabolism. However, several factors can affect the appetite, possibly impairing the efficacy of this strategy. This study aimed to investigate the effect of sow-related factors on average daily feed intake (ADFI) during WEI in 142 primiparous and 458 multiparous sows. After weaning, the sows received 4.3 kg/day of feed and the wastage was recorded. The ADFI after weaning was lower in primiparous than multiparous sows, and on estrous day than in 2 and 3 days preceding estrus (P ≤ 0.05). In primiparous sows, lower ADFI was observed if they had higher backfat thickness at 112 days of gestation (BFT ≥ 11.5 mm) or higher reserves at weaning (BFT ≥ 10.5 mm, caliper units ≥ 12 or ≥ 157 kg; P ≤ 0.05). Higher body reserves at the end of gestation (caliper units ≥ 12, BFT ≥ 11.0 mm, or BCS ≥ 3.0) or weaning (caliper units ≥ 13, BFT ≥ 12.5 mm) negatively affected the ADFI in multiparous sows (P < 0.04). Weaned litter size ≤ 11 piglets (P = 0.06) and shorter lactation length (P< 0.01) decreased the ADFI in primiparous sows. Greater loss in caliper units during lactation tended to reduce ADFI in primiparous and multiparous sows (P ≤ 0.07). Multiparous sows with greater losses in BFT and BCS had lower ADFI (P ≤ 0.03). The ADFI during WEI is reduced when sows are in estrus or if they have greater body reserves.

Zinc in Dog Nutrition, Health and Disease: A Review

Simple SummaryThis work compiles the current state of knowledge regarding zinc requirements of healthy dogs and biomarkers of zinc status. To ensure an adequate zinc status, it is important to know the zinc content of foods and their bioavailability to assess the need and the ideal supplementation strategy regarding levels and sources of additives in complete dog foods. As zinc is required for enzymatic, structural, and regulatory functions in the animal body, its nutritional status has been associated with several pathologies that may be due to, or exacerbated by, a deficit of dietary zinc supply.Zinc is an essential trace element, required for enzymatic, structural, and regulatory functions. As body reserves are scarce, an adequate zinc status relies on proper dietary supply and efficient homeostasis. Several biomarkers have been proposed that enable the detection of poor zinc status, but more sensitive and specific ones are needed to detect marginal deficiencies. The zinc content of commercial dry dog foods has great variability, with a more frequent non-compliance with the maximum authorized limit than with the nutritional requirement. The bioavailability of dietary zinc also plays a crucial role in ensuring an adequate zinc status. Despite controversial results, organic zinc sources have been considered more bioavailable than inorganic sources, albeit the zinc source effect is more evident after a restriction period of dietary zinc. Many disorders have been associated with inadequate zinc status, not being clear whether the occurrence of the disease is the consequence or the cause. This review presents data on zinc requirements and biomarkers for zinc status, that can be applied for the development of supplementation strategies of zinc in complete pet foods. Moreover, it provides an understanding of the role zinc plays in the health of dogs, and how altered zinc status affects diseases in dogs.

Metabolic status of crossbred Charolais × Nellore cows throughout the final third of gestation and lactation

The objective of this study was to evaluate the metabolic status of beef cows during the final third of gestation and thereafter until the end of the subsequent breeding season. The study was conducted using 30 beef cows, aged between 4 and 11 years, derived from crosses between Charolais and Nellore cattle. To assess the metabolic status of cows, we obtained measurements of body weight and condition (BW and BCS), and complemented these by analyzing the following blood metabolites: total proteins, globulins, albumin, glucose, cholesterol, and triglycerides. Assessments were performed at 95 days pre-calving, and again at 7, 21, 63, and 110 days post-calving. The experimental design was completely randomized with five collection periods and 30 repetitions (cows). The BW of cows was found to be highest at 110 days postpartum (489.1 kg), and loss of BW was observed between 21 and 63 days postpartum (-3.72 kg). The lowest BCS value was recorded after 63 days of lactation (2.85 points). With respect to blood metabolites, concentrations of total proteins were higher at 7 and 110 days postpartum relative to the levels recorded during gestation (8.3 and 8.3 vs. 7.7 g dL-1, respectively), whereas serum globulin levels were higher at 7, 21, and 110 days postpartum relative to those at gestation (5.2, 5.2, and 5.1 vs. 4.8 g dL -1, respectively). Compared with samples obtained during gestation, the highest levels of albumin (P &lt; 0.05) were observed at 7, 63, and 110 days postpartum (3.1, 3.1, and 3.2 vs. 2.9 g dL-1, respectively). Serum glucose was higher during pregnancy and in the first week of lactation relative to the values recorded after 21 and 63 days of lactation (80.9 and 76.7 vs 71.5 and 72.3 mg dL-1, respectively). Moreover, cholesterol concentrations increased with the progression of lactation, with the highest value being recorded at 110 days postpartum (222.1 mg dL-1). Collectively, the findings of this study, indicate that Charolais × Nellore cows raised exclusively on native pasture mobilize body reserves, lose weight, and show a negative energy balance during the first weeks of lactation, with detrimental consequences for subsequent reproductive activity.

Concentrate allowance and corn grain processing influence milk production, body reserves, milk fatty acid profile, and blood metabolites of dairy cows in the early postpartum period

The study goal was to determine the effects of a fast (FAS) or slow (SLW) incremental rate of concentrate feeding and corn processing method during the early postpartum period on lactational performance, body reserves, blood metabolites, and milk fatty acid (FA) profile. Forty multiparous Holstein cows were used in a randomized block design with a 2 × 2 factorial arrangement of treatments. Treatment diets were either a FAS [1.0 kg of dry matter (DM)/d] or SLW (0.25 kg of DM/d) incremental rate of concentrate feeding (up to 12 kg of DM/d) with either dry ground corn (DGC) or steam-flaked corn (SFC) as the primary starch source in concentrate. Treatments were fed from 5 to 64 d postpartum. The basal diet consisted of forage, soybean meal, and 5 kg/d concentrate in the postpartum period. Throughout the experiment, dry matter intake (DMI) and milk yield were measured daily, and milk components, body condition score, and body weight were recorded at 16-d intervals, whereas blood metabolites and milk FA profile were measured at 16 and 32 d in milk. The incremental rate of concentrate feeding interacted with corn processing method to affect plasma concentration of glucose with greater glucose in SFC treatment compared with DGC in cows fed with the FAS strategy. Cows fed FAS and SFC had a greater total DMI than those fed SLW and DGC counterparts (22.8 versus 22.1 kg and 22.7 versus 22.1 kg, respectively), and also SFC increased yield of actual milk compared with the DGC counterpart (42.7 versus 41.6 kg). The milk fat and energy-corrected milk yields were not different among treatments whereas milk protein yield was greater when SFC was fed. Greater incremental rate of concentrate feeding tended to increase milk lactose yield during the first 64 d of lactation. The loss of body condition score increased when cows were fed SLW for the entire period and plasma nonesterified fatty acids and β-hydroxybutyrate concentrations increased with the SLW strategy. The proportions of total trans 18:1 and trans-11 18:1 FA in milk fat were higher in cows fed FAS. However, feeding SLW enhanced milk de novo and mixed FA proportions compared with FAS, whereas the proportions of milk FA were not affected by corn grain processing method. The incremental rate of concentrate feeding had significant effects on DMI, milk yield, and body reserve changes. Although feeding SFC instead of DGC had benefits on DMI and milk yield at 48 and 64 d postpartum, treatments did not interact to affect production responses when cows were fed with the SLW strategy.

Capital-income breeding in wild boar: a comparison between two sexes

Organisms differ in the strategy adopted to fuel reproduction by using resources either previously acquired and stored in body reserves (capital breeding) or, conversely, acquired during their reproductive activity (income breeding). The choice of one or the other strategy is related to several internal and external factors which are counteractive in wild boar. Based on a large dataset of culled wild boar, we investigated individual body weight variability throughout the period of 1st September–31st January, which included the main part of the mating season, among different sex and age classes to determine their position along the capital-income breeding continuum. Though food resources were abundant during the rut, adult males lost body weight suggesting they adopted a predominantly capital breeding strategy, likely owing to the high intra-sexual competition entailed by the peculiar mating system of the species. On the contrary, subadult males seemed to behave as income breeders, likely enhancing the reproductive flexibility of wild boar populations. During the rut, females stored reserves, thus suggesting that they substantially relied on them to cover future reproductive costs.

Determining the factors affecting the gestational length in sheep.

This research aimed to determine the effects of body weight, the body condition score (BCS), body measurements, birth type (single offspring or twin birth), birth weight and sex on the gestational length in sheep (). Karayaka sheep raised on a private farm were used in the study. Progeny yield characteristics in sheep were also determined (). Estrus was monitored daily using teaser rams from August to September 2016. According to our findings, the pregnancy rate, infertility rate, fecundity, and twin and single birth rates were 93.52 %, 6.48 %, 93.52 %, 14.62 % and 85.38 % respectively. The effect of age on the BCS in sheep at mating was found to be significant (): BCS decreased as age increased. It was determined that there was a positive association between the BCS and live weight during the mating period (). The chest circumference, front shin circumference and body length were found to be higher in sheep with a BCS at mating time (). The middle rump width was significantly affected by the BCS (). In this study, the lowest and highest gestational lengths were found to be 148.90 and 151.41 d respectively. The gestational length in sheep was not found to be affected by age, the BCS, body measurements, sex or birth type (); however, it was observed that the gestational lengths for male offspring and single offspring (non-multiple births) were longer. In addition, it was detected that the gestational length was different in sheep with a BCS . The time spent in the womb is important with respect to obtaining a healthy lamb. For profitable production, a BCS of between 2.5 and 4 is recommended in sheep. It is thought that the use of body condition scoring, which is easy information for the breeder to utilize, will have a positive effect on determining the bodily reserves of sheep and the reproductive efficiency as well as on obtaining a healthy lamb. More studies on the gestational length in sheep are required.

Maternal effects on reproduction in the precocial European hare (Lepus europaeus).

In female mammals, reproduction, and in particular lactation, is the energetically most exigent life-history phase. Reproduction is strongly controlled by body reserves and food availability, so females with better body condition or food supply are believed to have higher reproductive output. Additionally, the growth and mortality of young mammals depends on their postnatal development. Therefore, the degree of precociality affects energetic demands for both mothers and young. To study the reproductive performance of the precocial European hare (Lepus europaeus), we analysed relationships between six predictor variables describing maternal and environmental effects and nine response variables relating to reproduction from 217 captive females. We compared the data with those of precocial and altricial mammal species from an extensive literature search. For hares, we found: (1) Heavier females had heavier litters at birth. (2) In summer and spring, total litter mass was larger than in winter. (3) At the end of lactation, the litters of multiparous females were heavier than those of primiparous females. (4) Both older females and females giving birth for the first time had relatively high leveret mortality during lactation. Comparing our results with the literature for other mammals revealed that the body condition (i.e., body mass) of females before birth is predictive of reproductive parameters in both precocial and altricial species. In the precocial hare, female body condition is no longer predictive of reproductive parameters at the end of lactation, whereas in altricial species, female body condition remains predictive of reproduction (litter mass at the end of lactation, offspring mortality) until the end of lactation. We conclude that these effects are caused by precocial offspring feeding on solid food soon after birth and, thus, being less dependent on the mother’s body condition during lactation than altricial offspring. In line with this, precociality might have evolved as a way of buffering offspring against maternal effects.

Pattern of anaesthesia techniques for herniotomy at a southwestern tertiary health institution: a 5-year review

Background: Anaesthesia for herniotomy may be challenging because the margin of error in managing such a young patient can be extremely small since the body reserves are limited and the organ systems may not be fully developed. Also, the psychological, physiological and pharmacological responses to anaesthesia are quite different from adult. Safe and effective care of children under anaesthesia is therefore crucial. This study aims to audit the pattern of anaesthetisia techniques used and their associated complications during herniotomy procedure in our health facility. Material and methods: This is a retrospective review of patients’ files, theatre records and anaesthetic-record charts of herniotomy cases performed in a tertiary health Institution from January 2011 to December 2015. Relevant clinical information were entered into proforma designed for the study. Data was analysed with descriptive statistics using the Statistical Package for Social Sciences (SPSS) version 20 Chicago IL (U.S.A). Inferential statistics of Chi-Square, Mann-Whitney and Kruskal-Wallis Test were alsoperformed. Results: One hundred and fortyfour in-patient children who belonged to American Society of Anesthesiologists Physical Health Status (ASA) grade I and II had herniotomies during the study period. The mean age is 4.21±3.72years (range, 6months – 16years) with male to female ratio of 47:1 (i.e 141 to 3). General anaesthesia (135, 94%) of various techniques was the most common technique while regional anaesthesia was only employed in nine (6%) children. The regional anaesthesia techniques were caudal block 1 (0.7%) and subarachnoid block 8 (5.5%) and were sedated to allow for cooperation in some of the cases. One hundred and twenty-four (86%) children presented as simple, elective cases while twenty (14%) children as complicated or emergency cases. Conclusion: This study showed that herniotomy can be safely performed under various options of anaesthesia techniques depending on the expertise of the anaesthetists involved. The simple, electives inguinal hernia and hydroceles could have been performed as day cases.

Effects of nutrient restriction on the metabolic profile of Bos indicus-influenced and B. taurus suckled beef cows

Recent research from our group demonstrated that Bos indicus-influenced suckled beef cows had greater resilience to withstand nutrient restriction and establish pregnancy compared with B. taurus cows exposed to the same conditions. To further understand these findings, differences in metabolic profile between these same B. indicus-influenced and B. taurus females were explored. Suckled beef cows (n = 134) were enrolled in a completely randomized design with a 2 × 2 factorial arrangement of treatments. On day −21, Angus (AN; Bos taurus) and Brangus (BN; B. indicus-influenced) cows were randomly assigned to 1) a diet that met daily energy maintenance requirements (MAINT), or 2) a diet that restricted intake to 70% of the daily energy maintenance requirements (RESTR). Cows were exposed to an estrus synchronization protocol and received an embryo 7 d after ovulation was pharmacologically induced on day 0. Blood samples were collected on days −21 and 19 to determine circulating concentrations of non-esterified fatty acids (NEFA), β-hydroxybutyrate (BHB), insulin, glucose, and IGF-1. Pregnancy status after embryo transfer was determined on day 28. As a consequence of the proposed diets, cows in the RESTR diet had less body condition score (BCS) on day 19 (P = 0.008) across breed types. Moreover, BCS change from day −21 to 19 was included as independent covariate into subsequent analyses, allowing for the comparison of breed types under an equivalent level of body reserve mobilization. A breed × diet interaction was observed for plasma insulin (P = 0.03) and IGF-1 (P = 0.04) on day 19, where AN–RESTR cows had less plasma concentrations on day 19 compared with AN–MAINT cows. Diets did not impact (P > 0.10) plasma insulin and IGF-1 concentrations in BN cows. No diet or breed effects were observed in circulating concentrations of NEFA, BHB, and glucose (P > 0.10). Across breed types and nutritional treatment, there was positive linear effect (P ≤ 0.04) of plasma concentrations of insulin and IGF-1 on the probability of pregnancy to fixed-time embryo transfer. In summary, the negative impacts of nutrient restriction on the somatotropic axis, independently of body tissue mobilization, were heightened in Bos taurus females compared with B. indicus-influenced cohorts, which corroborate with the differences observed in fertility between these subspecies.