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Livestock guarding dogs are a valuable adjunct to the pastoral community. Having been traditionally selected for their working ability, they fulfil their function with minimal interaction or command from their human owners. In this study, the population structure and the genetic differentiation of three Italian livestock guardian breeds (Sila’s Dog, Maremma and Abruzzese Sheepdog and Mannara’s Dog) and three functionally and physically similar breeds (Cane Corso, Central Asian Shepherd Dog and Caucasian Shepherd Dog), totalling 179 dogs unrelated at the second generation, were investigated with 18 autosomal microsatellite markers. Values for the number of alleles per locus, observed and expected heterozygosity, Hardy–Weinberg Equilibrium, F stats, Nei’s and Reynold’s genetic distances, clustering and sub-population formation abilities and individual genetic structures were calculated. Our results show clear breed differentiation, whereby all the considered breeds show reasonable genetic variability despite small population sizes and variable selection schemes. These results provide meaningful data to stakeholders in specific breed and environmental conservation programmes.
This study assessed milk productivity, demographic characteristics and workload distribution on a single high-yield dairy ewe farm in Spain (Avila, Spain; continental climate, latitude of 40.90 N, altitude of 900 m) over a 7-year period considering a transition from a herd management system involving five lambings per year (5LY) to a system involving 10 lambings per year (10LY). The 5LY system was practiced on the farm from 2010 to 2012 and the 10LY system from 2014 to 2015, with 2009 and 2013 being considered transition years. During this period, 27 415 lactations were recorded from an average of 3746 Lacaune sheep/year. Several productivity parameters were higher in 2014 to 2015 than in 2010 to 2012: milk yield/lactation (370±156 v. 349±185 l), lactation length (218±75 v. 192±75 days) and dry period length (53.5±38.3 v. 69.1±34.8 days) (all P<0.0001). During 2014 to 2015, investment in new lambing facilities was possible, workload was distributed more uniformly throughout the year, workload per worker was smaller, rate of ewe culling was lower (35.39±0.53% v. 42.51±7.51%), ewe longevity was greater and higher-order lactations were more numerous (P<0.0001). On the other hand, during 2010 to 2012, daily production was higher (1.73±1.66 v. 1.70±0.62 l/day; P=0.038), the interlambing period was shorter (283±50 v. 302±44 days; P<0.0001) and lambings/ewe per year were greater (1.42±0.01 v. 1.30±0.01; P<0.05). These results suggest that a 10LY herd management system can be compatible with profitability, productivity and good animal and worker’s welfare on a high-yield dairy farm, and may even be associated with better outcomes than a 5LY system.
The European Union Effort Sharing Regulation (ESR) will require a 30% reduction in greenhouse gas (GHG) emissions by 2030 compared with 2005 from the sectors not included in the European Emissions Trading Scheme, including agriculture. This will require the estimation of current and future emissions from agriculture, including dairy cattle production systems. Using a farm-scale model as part of a Tier 3 method for farm to national scales provides a more holistic and informative approach than IPCC (2006) Tier 2 but requires independent quality control. Comparing the results of using models to simulate a range of scenarios that explore an appropriate range of biophysical and management situations can support this process by providing a framework for placing model results in context. To assess the variation between models and the process of understanding differences, estimates of GHG emissions from four farm-scale models (DairyWise, FarmAC, HolosNor and SFARMMOD) were calculated for eight dairy farming scenarios within a factorial design consisting of two climates (cool/dry and warm/wet)×two soil types (sandy and clayey)×two feeding systems (grass only and grass/maize). The milk yield per cow, follower:cow ratio, manure management system, nitrogen (N) fertilisation and land area were standardised for all scenarios in order to associate the differences in the results with the model structure and function. Potential yield and application of available N in fertiliser and manure were specified separately for grass and maize. Significant differences between models were found in GHG emissions at the farm-scale and for most contributory sources, although there was no difference in the ranking of source magnitudes. The farm-scale GHG emissions, averaged over the four models, was 10.6 t carbon dioxide equivalents (CO2e)/ha per year, with a range of 1.9 t CO2e/ha per year. Even though key production characteristics were specified in the scenarios, there were still significant differences between models in the annual milk production per ha and the amounts of N fertiliser and concentrate feed imported. This was because the models differed in their description of biophysical responses and feedback mechanisms, and in the extent to which management functions were internalised. We conclude that comparing the results of different farm-scale models when applied to a range of scenarios would build confidence in their use in achieving ESR targets, justifying further investment in the development of a wider range of scenarios and software tools.
Fatty acids are important modulators of inflammatory responses, in particular, n-3 and n-6 essential fatty acids and CLA have received particular attention for their ability to modulate inflammation. The objectives of this study were to compare the effects of CLA and essential fatty acids on the expression of pro and anti- inflammatory cytokines and their protective efficacy against inflammatory status in mammary gland by an in vitro model based on bovine mammary epithelial cells (BME-UV1). Bovine mammary epithelial cells were treated with complete medium containing either 50 µM of cis-9, trans-11 CLA (c9,t11 CLA) or trans-10, cis-12 CLA (t10,c12 CLA) or (α)-linolenic acid (aLnA) or (γ)-linolenic acid (gLnA) or linoleic acid (LA). After 48 h by fatty acids administration the cells were treated for 3 h with 20 µM of lipopolysaccharide (LPS) to induce inflammatory stimulus. Reactive oxygen species (ROS) production after treatments was assessed to verify and to compare the potential protection of different fatty acids against LPS-induced oxidative stress. The messenger RNA abundance of bovine pro and anti-inflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and interleukine-10 (IL-10)) and peroxisome proliferator receptor-α/γ (PPARγ/α) were determined in BME-UV1 by real-time PCR. The results showed that cells treated with fatty acids and LPS increased ROS production compared with control cells. Among treatments, cells treated with c9,t11 CLA and t10,c12 CLA isomers revealed significant lower levels of ROS production compared with other fatty acids. All fatty acids reduced the gene expression of pro- and anti-inflammatory cytokines. Among fatty acids, t10,c12 CLA, LA and gLnA showed an homogeneous reduction of the three pro-inflammatory cytokines and this may correspond to more balanced and efficient physiological activity and may trigger a better protective effect. The PPARγ gene expression was significantly greater in cells treated with t10,c12 CLA, aLnA and LA, whereas the PPARα gene expression levels were significantly lower in cells treated with all different fatty acids, compared with the control. These results suggest that fatty acids inhibited the transcription of pro-inflammatory cytokines by the upregulation of PPARγ expression.
Fat supplementation plays an important role in defining milk fatty acids (FA) composition of ruminant products. The use of sources rich in linoleic and α-linolenic acid favors the accumulation of conjugated linoleic acids isomers, increasing the healthy properties of milk. Ruminal microbiota plays a pivotal role in defining milk FA composition, and its profile is affected by diet composition. The aim of this study was to investigate the responses of rumen FA production and microbial structure to hemp or linseed supplementation in diets of dairy goats. Ruminal microbiota composition was determined by 16S amplicon sequencing, whereas FA composition was obtained by gas-chromatography technique. In all, 18 pluriparous Alpine goats fed the same pre-treatment diet for 40±7 days were, then, arranged to three dietary treatments consisting of control, linseed and hemp seeds supplemented diets. Independently from sampling time and diets, bacterial community of ruminal fluid was dominated by Bacteroidetes (about 61.2%) and Firmicutes (24.2%) with a high abundance of Prevotellaceae (41.0%) and Veillonellaceae (9.4%) and a low presence of Ruminococcaceae (5.0%) and Lachnospiraceae (4.3%). Linseed supplementation affected ruminal bacteria population, with a significant reduction of biodiversity; in particular, relative abundance of Prevotella was reduced (−12.0%), whereas that of Succinivibrio and Fibrobacter was increased (+50.0% and +75.0%, respectively). No statistically significant differences were found among the average relative abundance of archaeal genera between each dietary group. Moreover, the addition of linseed and hemp seed induced significant changes in FA concentration in the rumen, as a consequence of shift from C18 : 2n-6 to C18 : 3n-3 biohydrogenation pathway. Furthermore, dimethylacetal composition was affected by fat supplementation, as consequence of ruminal bacteria population modification. Finally, the association study between the rumen FA profile and the bacterial microbiome revealed that Fibrobacteriaceae is the bacterial family showing the highest and significant correlation with FA involved in the biohydrogenation pathway of C18 : 3n-3.
Goats have played a key role as source of nourishment for humans in their expansion all over the world in long land and sea trips. This has guaranteed a place for this species in the important and rapid episode of livestock expansion triggered by Columbus’ arrival in the Americas in the late 1400s. The aims of this study are to provide a comprehensive perspective on genetic diversity in American goat populations and to assess their origins and evolutionary trajectories. This was achieved by combining data from autosomal neutral genetic markers obtained in more than two thousand samples that encompass a wide range of Iberian, African and Creole goat breeds. In general, even though Creole populations differ clearly from each other, they lack a strong geographical pattern of differentiation, such that populations of different admixed ancestry share relatively close locations throughout the large geographical range included in this study. Important Iberian signatures were detected in most Creole populations studied, and many of them, particularly the Cuban Creole, also revealed an important contribution of African breeds. On the other hand, the Brazilian breeds showed a particular genetic structure and were clearly separated from the other Creole populations, with some influence from Cape Verde goats. These results provide a comprehensive characterisation of the present structure of goat genetic diversity, and a dissection of the Iberian and African influences that gave origin to different Creole caprine breeds, disentangling an important part of their evolutionary history. Creole breeds constitute an important reservoir of genetic diversity that justifies the development of appropriate management systems aimed at improving performance without loss of genomic diversity.
Soya bean is the main protein source in poultry feed but rising prices make an alternative protein source necessary. Insects, such as the black soldier fly (Hermetia illucens), may be an attractive solution for hens, although little information is available on their effect on egg quality. The present study aims to fill this gap by testing the effect of 100% replacement of soya bean with H. illucens larva meal in the diet of Lohmann Brown Classic laying hens for 21 weeks. At the end of the trial, the eggs were characterized for parameters such as weight, colour, proximate composition of albumen and yolk, and content of carotenoids, tocopherols and cholesterol. The fatty acid profile of yolks was also determined. Hens fed the insect-based diet produced eggs (HIM group) with a higher proportion of yolk than the group fed the soya bean-based diet (SBM group). HIM was associated with redder yolks (red index 5.63 v. 1.36) than SBM. HIM yolks were richer in γ-tocopherol (4.0 against 2.4 mg/kg), lutein (8.6 against 4.9 mg/kg), β-carotene (0.33 against 0.19 mg/kg) and total carotenoids (15 against 10.5 mg/kg) than SBM yolks. The fatty acid composition of HIM yolks was almost identical to that of SBM yolks. Finally, HIM yolks contained 11% less cholesterol than SBM yolks. These results suggest that H. illucens larva meal is a suitable total substitute for soya bean meal in the diet of Lohmann Brown Classic laying hens. A sustainable alternative to the plant protein source therefore seems feasible.
The objective of this study was to evaluate the effect of supplemented condensed tannins (CT) from the bark of the Black Wattle tree (Acacia mearnsii) on production variables and N use efficiency in high yielding dairy cows. A feeding trial with 96 lactating German Holstein cows was conducted for a total of 169 days, divided into four periods. The animals were allotted to two groups (control (CON) and experimental (EXP) group) according to milk yield in previous lactation, days in milk (98), number of lactations and BW. The trial started and finished with a period (period 1 and 4) where both groups received the same ration (total-mixed ration based on grass and maize silage, ensiled sugar beet pulp, lucerne hay, mineral premix and concentrate, calculated for 37 kg energy-corrected milk). In between, the ration of EXP cows was supplemented with 1% (CT1, period 2) and 3% of dry matter (DM) (CT3, period 3) of a commercial A. mearnsii extract (containing 0.203 g CT/g DM) which was mixed into the concentrate. In period 3, samples of urine and faeces were collected from 10 cows of each group and analyzed to estimate N excretion. Except for a tendency for a reduced milk urea concentration with CT1, there was no difference between groups in period 2 (CON v. CT1; P>0.05). The CT3 significantly reduced (P<0.05) milk protein yield, the apparent N efficiency (kg milk N/k feed N) and milk urea concentration; but total milk yield and energy-corrected milk yield were not affected by treatment. Furthermore, as estimated from 10 cows per group and using urinary K as a marker to estimate the daily amount of urine voided, CT3 caused a minor shift of N compounds from urine to faeces, as urea-N in urine was reduced, whereas the N concentration in faeces increased. As an improvement in productivity was not achieved and N use efficiency was decreased by adding the CT product it can be concluded that under current circumstances the use in high yielding dairy cows is not advantageous.
Preweaning mortality in piglets is a welfare issue, as well as an ethical and economic concern in commercial pig farming. Studying the causes of preweaning mortality and their prevalence is necessary to reduce losses. Preweaning piglet mortality was investigated in a field study including 347 sows from 14 loose-housed Norwegian piglet-producing herds. A total of 5254 piglets were born in these herds during the study period, and 1200 piglets were necropsied. The cause of death was based on pathoanatomical diagnosis (PAD). Preweaning mortality of all piglets in the study was 23.4%, including 6.3% stillborn. The two main causes of preweaning mortality in live-born piglets (n=4924) were trauma (7.1%) and starvation (2.7%). Piglets dying of an infection accounted for 2.0%. Among the necropsied piglets (n=1200), 29.1% had died due to trauma, 26.8% were categorized as stillborn and 11% had died of starvation. Piglets that had died of trauma, had a mean time of death of 1 lactation day (LD 1), ranging from LD 0 to LD 21. The mean time of death of piglets that died due to bacterial infection was LD 9, ranging from LD 0 to LD 31, with Escherichia coli accounting for most infections found in necropsied piglets. Farmers were able to identify death by trauma in piglets, but were less able to identify death due to hunger. Most piglets that died in the preweaning period, died of trauma. Surprisingly, this included large and well-fed piglets. The second most prevalent cause of preweaning mortality was starvation. Improved monitoring may reveal piglets with low body mass index, and additional nutrition may contribute to increase the survival rate.
The aim of this review is to focus the attention on the nutrition ecology of the heavy metals and on the major criticisms related to the heavy metals content in animal feeds, manure, soil and animal-origin products. Heavy metals are metallic elements that have a high density that have progressively accumulated in the food chain with negative effects for human health. Some metals are essential (Fe, I, Co, Zn, Cu, Mn, Mo, Se) to maintain various physiological functions and are usually added as nutritional additives in animal feed. Other metals (As, Cd, F, Pb, Hg) have no established biological functions and are considered as contaminants/undesirable substances. The European Union adopted several measures in order to control their presence in the environment, as a result of human activities such as: farming, industry or food processing and storage contamination. The control of the animal input could be an effective strategy to reduce human health risks related to the consumption of animal-origin products and the environmental pollution by manure. Different management of raw materials and feed, animal species as well as different legal limits can influence the spread of heavy metals. To set up effective strategies against heavy metals the complex interrelationships in rural processes, the widely variability of farming practices, the soil and climatic conditions must be considered. Innovative and sustainable approaches have discussed for the heavy metal nutrition ecology to control the environmental pollution from livestock-related activities.
In the past decades, the intense selection practices carried out in order to develop fast growing and high breast-yield turkey hybrids profoundly modified the muscle physiology leading to the development of growth-related alterations and muscular abnormalities. White striations of variable thickness have been particularly observed on the ventral surface of Pectoralis major muscle belonging from heavy male turkeys since several years. However, although the effects of white striping (WS) have been extensively studied on broilers, this condition was not considered as a main quality issue by both turkey producers and meat industry. Thus, this study aimed at evaluating whether the occurrence of WS in heavy male turkeys affects the quality traits and technological properties of meat to the same extent previously observed for broilers. In two replications, 72 Pectoralis major muscles were classified as: normal (NORM), moderate WS (MOD) and severe WS (SEV) cases. The whole muscle was weighed and cut in order to assess colour, ultimate pH, water holding (drip and cooking losses) and binding (marinade uptake) capacities, NMR relaxation properties, shear force as well as proximate composition of meat. The Pectoralis major muscles affected by WS (both moderate and severe cases) exhibited a one-fifth increased weight in comparison with their NORM counterpart. However, the occurrence of WS only partially affected the proximate composition of the meat. In detail, although moisture, collagen and protein contents did not differ among the groups, if compared with NORM, higher lipid levels were found in SEV muscles, whereas MOD had intermediate values. On the other hand, both MOD and SEV exhibited lower ash content. Despite these variations in proximate composition, both water holding and binding capacities of turkey breast meat were not affected by WS. Indeed, quality traits of raw (pH, colour, cooking losses and shear force) and marinated (uptake, cooking losses and shear force) meat as well as water distribution within the muscle tissue did not differ between NORM and WS cases. Overall, if compared with broilers, WS only marginally affected quality traits of turkey breast meat. It might thus be hypothesised a diverse specie-specific physiological response to the pressure in muscle tissue induced by the selection in turkeys that, although analogously led to the occurrence of WS, results in limited effects on meat quality.
This study was conducted within the context of the Animal Welfare Indicators (AWIN) project and the underlying scientific motivation for the development of the study was the scarcity of data regarding inter-observer reliability (IOR) of welfare indicators, particularly given the importance of reliability as a further step for developing on-farm welfare assessment protocols. The objective of this study is therefore to evaluate IOR of animal-based indicators (at group and individual-level) of the AWIN welfare assessment protocol (prototype) for dairy goats. In the design of the study, two pairs of observers, one in Portugal and another in Italy, visited 10 farms each and applied the AWIN prototype protocol. Farms in both countries were visited between January and March 2014, and all the observers received the same training before the farm visits were initiated. Data collected during farm visits, and analysed in this study, include group-level and individual-level observations. The results of our study allow us to conclude that most of the group-level indicators presented the highest IOR level (‘substantial’, 0.85 to 0.99) in both field studies, pointing to a usable set of animal-based welfare indicators that were therefore included in the first level of the final AWIN welfare assessment protocol for dairy goats. Inter-observer reliability of individual-level indicators was lower, but the majority of them still reached ‘fair to good’ (0.41 to 0.75) and ‘excellent’ (0.76 to 1) levels. In the paper we explore reasons for the differences found in IOR between the group and individual-level indicators, including how the number of individual-level indicators to be assessed on each animal and the restraining method may have affected the results. Furthermore, we discuss the differences found in the IOR of individual-level indicators in both countries: the Portuguese pair of observers reached a higher level of IOR, when compared with the Italian observers. We argue how the reasons behind these differences may stem from the restraining method applied, or the different background and experience of the observers. Finally, the discussion of the results emphasizes the importance of considering that reliability is not an absolute attribute of an indicator, but derives from an interaction between the indicators, the observers and the situation in which the assessment is taking place. This highlights the importance of further considering the indicators’ reliability while developing welfare assessment protocols.
The study investigated whether different dietary energy and protein sources affect laying performance, antioxidant status, fresh yolk fatty acid profile and quality of salted yolks in laying ducks. In all, 360 19-week-old Longyan ducks were randomly assigned to four diets in a factorial arrangement (2×2). The four diets consisted of two energy sources, corn (CO) or sorghum (SO) and two protein sources, soybean meal (SM) and rapeseed meal with corn distillers dried grains with solubles (RMD), and each treatment contained six replicates of 15 birds each. The experimental diets were isocaloric (metabolizable energy, 10.84 MJ/kg) and isonitrogenous (CP, 17%). The results showed that egg production, average egg weight, egg mass and feed conversion ratio were not affected by diets (P>0.05). Plasma contents of reduced glutathione (GSH), GSH/oxidized glutathione and total antioxidant capacity were lower (P<0.05) in ducks fed the RMD diets compared with those fed SM diets with a substantial increase (P=0.006) in plasma content of malondialdehyde (MDA). Egg yolks from ducks fed SO diets had higher proportions of polyunsaturated fatty acids (PUFA) and lower saturated and monounsaturated fatty acids compared with CO diets (P<0.001). Similarly, ducks fed RMD diets had a higher content of PUFA and n-6/n-3 ratio in fresh yolks (P<0.001), and increased salted yolk MDA, carbonylated proteins content and incidence of hard salted yolks (P<0.05) compared with SM diets. Scanning electron microscopy showed that salted yolks contained rougher polyhedral granules and fewer fat droplets, and were surrounded with a layer of bunchy fibers in ducks fed SO+RMD than those fed CO+SM diet. In conclusion, the current study showed that feeding laying ducks with diets containing SO or RMD reduced antioxidant capacity and increased egg yolk concentrations of PUFA. It appeared that egg yolks from ducks fed these diets were more sensitive to lipid peroxidation and protein oxidation during salting, and reduced the quality of salted yolks.
The aim of this study was to analyze milk protein composition in purebred and crossbred dairy cattle and estimate the effects of individual sources of variation on the investigated traits. Milk samples were collected from 505 cows from three commercial farms located in Northern Italy, some of which had originated from crossbreeding programs, although most were purebred Holsteins (HO). The basic crossbreeding scheme was a three-breed rotational system using Swedish Red (SR) semen on HO cows (SR×HO), Montbeliarde (MO) semen on SR×HO cows (MO×(SR×HO)) and HO semen again on MO×(SR×HO) cows. A smaller number of purebred HO from each of the herds were mated inverting the breed order (MO×HO and SR×(MO×HO)) or using Brown Swiss (BS) bulls (BS×HO) then MO bulls (MO×(BS×HO)). Milk samples were analyzed by reverse-phase HPLC to obtain protein fraction amounts (g/l) and proportions (% of total true protein). Traits were analyzed using a linear model, which included the fixed effects of herd-test-day (HTD), parity, days in milk and breed combination. Results showed that milk protein fractions were influenced by HTD, stage of lactation, parity and breed combination. The increase in protein concentration during lactation was due in particular to β-casein (β-CN), αS1-CN and β-lactoglobulin (β-LG). The higher protein content of primiparous milk was mainly due to higher concentrations of all casein fractions. The milk from crossbred cows had higher contents and proportions of κ-CN and α-lactalbumin (α-LA), lower proportions of β-LG and greater proportion of caseins/smaller in whey proteins on milk true protein than purebred HO. The three-way crossbreds differed from two-way crossbreds only in having greater proportions of α-LA in their milk. Of the three-way crossbreds, the SR sired cows yielded milk with a smaller content and proportion of β-LG than the MO sired cows, and, consequently, a higher proportion of caseins than whey proteins. Results from this study support the feasibility of using crossbreeding programs to alter milk protein profiles with the aim of improving milk quality and cheese-making properties.
The aim of this study is to assess how the fat molecular structure and its glycerol-to-fatty acid ratio (G : FA) affect the fatty acid (FA) apparent absorption of palm oils in broiler chickens. The experimental diets were the result of a basal diet supplemented with 6% of different palm oils. Native palm oil (N), rich in triacylglycerols, was the positive control (T1), and acid palm oil (A), rich in free FA, was the negative control (T2). In order to improve the nutritive value of A, two different nutritional strategies were performed. The first strategy was achieved by adding increasing amounts of free glycerol (G) (4% (T3), 8% (T4) and 16% (T5)) to A, and the second one by adding increasing amounts of mono- (MAG) and diacylglycerols (DAG), coming from re-esterified palm oil (E) (40% (T6), 70% (T7), and 100% (T8)) to A. As a result, eight dietary treatments were formulated with a G : FA ratio ranging from 0.04 to 0.67. These treatments were randomly assigned to 192 one-day-old female broiler chickens (Ross 308), distributed in 48 cages. The results showed how, by keeping the G : FA ratio constant (0.33 mol/mol), the diet with a high MAG and DAG content (T7) achieved higher saturated FA apparent absorption values than did the diet with a high triacylglycerol content (T1) and this, in turn, more than did the diet with a high free FA content (T4). The behavior of oils with high or low G : FA ratio was dependent on whether G was in a free state or esterified as part of acylglycerol molecules. Thus, increasing amounts of G to A did not enhance the total FA apparent absorption, but rather quite the opposite, even impairing the absorption of mono- and polyunsaturated FA. However, increasing amounts of E (rich in MAG and DAG) to A (rich in FFA) did enhance total FA apparent absorption, primarily due to the increased absorption of saturated FA. In conclusion, the greater the G : FA ratio of a palm oil, the greater the absorption of total FA, as long as G is esterified as part of acylglycerol molecules. Thus, the re-esterification process for obtaining E makes sense in order to give added value to A, achieving even greater digestibility values than does its corresponding N.