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1.
J Dairy Sci ; 107(3): 1549-1560, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37806626

RESUMO

The aim of this study was to infer the effects of heat stress (HS) of dams during late gestation on direct and maternal genetic parameters for traits related to milk production and milk quality parameters (90,558 records) in Italian Brown Swiss cattle (12,072 cows in 617 herds). Daily average temperature-humidity indices (THI) during the last 56 d of pregnancy were calculated, using the climate data from the nearest public weather station for each herd. Heat load effects were considered as the average across the entire periods considering a thermoneutrality condition for data below the THI 60. For parameter estimation a random regression model using the second-order Legendre polynomial regression coefficient for THI considering both animal and maternal effect for heat load. Direct heritability increased sharply from THI 60 to 65, then decreased gradually up to THI ∼72, and sharply thereafter. Maternal heritability showed a different trend, with values close to 0 up until to THI 65 and slightly increasing toward extreme THI values. The study suggests a lower threshold of THI 60 for the onset of HS. Higher heritability values indicate greater selective efficiency in the THI range of 65 to 70, even if a higher standard deviation value have been detected. The effects of high THI during intrauterine life varied among traits with different heritability levels. Genetic correlations for milk, fat, and protein content at 60 THI with increasing value of environmental variable, remained constant (∼0.90) until THI >75, where they slightly decreased (∼0.85). Fat and protein yields, as well as milk and energy-corrected milk, showed correlations dropping to 0.80 around THI 67 to 68 and stabilizing between 0.75 and 0.85 at extreme THI values. Maternal component correlations dropped close to zero, with negative values for protein content at THI 65 to 70. Antagonism between direct and maternal components was stronger for intermediate THI values but less divergent for extremes. Genotype by environment interaction was observed, indicating the selection of resilient animals would be theoretically possible. In the future, the application of climate variables in selection schemes first should take into account the dimensions of the genetic correlations to be able to decide between the simple inclusion of the environmental effect in the statistical models, rather than a real parallel genetic evaluation.


Assuntos
Doenças dos Bovinos , Transtornos de Estresse por Calor , Feminino , Bovinos/genética , Animais , Gravidez , Lactação , Temperatura Alta , Leite/metabolismo , Tempo (Meteorologia) , Umidade , Resposta ao Choque Térmico , Transtornos de Estresse por Calor/veterinária , Itália , Doenças dos Bovinos/metabolismo
2.
J Dairy Sci ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38908697

RESUMO

Heat stress (HS) is one of the pivotal causes of economic losses in dairy industries and affects welfare and performance, but its effect on milk microbiota remains elusive. It is also unclear if and how different breeds may cope with HS in sustaining productive performance. The objectives of this study were to compare a) the performance of 2 dairy breeds, namely Holstein and Brown Swiss, subjected to HS and b) the different effects of HS on the milk microbiota of the 2 breeds in thermal comfort conditions and HS. The study was carried out on 36 dairy cows, 18 per breed. The HS was induced by switching off the cooling system during a natural heat wave for 4 d. Besides the Temperature Humidity Index (THI), the animal stress was confirmed by measuring respiratory frequency and rectal temperature twice daily at 4 a.m. and 3 p.m. The HS differently impacted the 2 breeds. Rectal temperatures were higher in Holstein cows, while no changes in rectal temperature were found in Brown Swiss. Milk yield recording and sampling were performed during the morning milking of d 1 (at 4.00 a.m.) and afternoon milking of d 4 (at 5.00 p.m.). Productive parameters were also different: milk yield, fat-corrected milk, energy-corrected milk, protein and casein content, and renneting parameters were decreased in Holstein but remained unaffected in Brown Swiss. The HS also modified the milk microbiota of the 2 breeds differently. During HS, the Brown Swiss milk microbiota was richer (α diversity) than the Holstein one. Comparing the time points before and during HS within breeds showed that Brown Swiss milk microbiota was less affected by HS than Holstein's. Under the same thermal comfort condition, milk microbiota did not discriminate between Brown Swiss and Holstein. Consistently with α and ß diversity, the number of operational taxonomic units (OTUs) at the genus level that changed their abundance during HS was higher in Holstein (74 OTUs) than in Brown Swiss (only 20 OTUs). The most significant changes in abundance affected Acinetobacter, Chryseobacterium, Cutibacterium, Enterococcus, Lactococcus, Prevotella-9, Serratia, and Streptococcus. In conclusion, the present report confirms and extends previous studies by demonstrating that Brown Swiss cows regulate their body temperature better than the Holstein breed. The relative thermal tolerance to HS compared with Holstein is also confirmed by changes in milk uncultured microbiota, which were more evident in Holstein than in Brown Swiss.

3.
J Dairy Sci ; 106(3): 1889-1909, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36586797

RESUMO

Due to its geographical position and a highly variable orography, Italy is characterized by several climatic areas and thus, by many different dairy cow farming systems. Brown Swiss cattle, in this context, are a very appreciated genetic resource for their adaptability and low metabolic requirement. The significant heterogeneity in farming systems may consist of genotype by environment (G × E) interactions with neglected changes in animals' rank position. The objective of this study was to investigate G × E for heat tolerance in Brown Swiss cattle for several production traits (milk, fat, and protein yield in kilograms; fat, protein, and cheese yield in percentage) and 2 derivate traits (fat-corrected milk and energy-corrected milk). We used the daily maximum temperature-humidity index (THI) range, calculated according to weather stations' data from 2008 to 2018 in Italy, and 202,776 test-day records from 23,396 Brown Swiss cows from 639 herds. Two different methodologies were applied to estimate the effect of the environmental variable (THI) on genetic parameters: (1) the reaction norm model, which uses a continuous random covariate to estimate the animal additive effect, and (2) the multitrait model, which splits each production pattern as a distinct and correlated trait according to the first (a thermal comfort condition), third (a moderate heat stress condition), and fifth (a severe heat stress condition) mean THI value quintile. The results from the reaction norm model showed a descending trend of the additive genetic effect until THI reached the value of 80. Then we recorded an increase with high extreme THI values (THI 90). Permanent environmental variance at increasing THI values revealed an opposite trend: The plot of heritability and the ratio of animal permanent environmental variance to phenotypic variance showed that when the environmental condition worsens, the additive genetic and permanent environmental component for production traits play a growing role. The negative additive genetic correlation between slope and linear random coefficient indicates no linear relationship between the production traits or under heat stress conditions, except for milk yield and protein yield. In tridimensional wireframe plots, the extreme margin decreases until a minimum of ∼0.90 of genetic correlation in the ECM trait, showing that the magnitude of G × E interaction is greater than the other traits. Genetic correlation values in Brown Swiss suggest the possibility of moderate changes in animals' estimated breeding value in heat stress conditions. Results indicated a moderate G × E interaction but significant variability in sire response related to their production level.


Assuntos
Doenças dos Bovinos , Transtornos de Estresse por Calor , Feminino , Bovinos , Animais , Lactação/fisiologia , Interação Gene-Ambiente , Resposta ao Choque Térmico , Leite/metabolismo , Genótipo , Temperatura Alta , Umidade , Transtornos de Estresse por Calor/veterinária , Doenças dos Bovinos/metabolismo
4.
J Dairy Sci ; 105(10): 8143-8157, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36028343

RESUMO

Concentration is a key determinant in the overall positive impact of terpenes on milk and cheese aroma; additionally, route of intake may affect the achievable concentrations of dietary terpenes in milk and cheese. In this study, we explored the possibility that the amount of the monoterpene limonene transferred to sheep milk and its corresponding cheese could differ depending on the route of intake and that the aroma profile of these products could also differ. To this aim, 12 lactating dairy ewes were repeatedly exposed to limonene by the oral or respiratory route during a 48-h test period, according to a 3 × 3 Latin square experimental design. Limonene content was measured in individual and bulk milk samples, in 1-d-old and 15-d-old Caciotta cheese obtained from that milk, in the related whey and curd, and in the air inhaled by the ewes in the respiratory treatment group (to obtain an estimate of the dose actually supplied by this route). Bulk milk and fresh (1-d-old) cheese underwent sensory analysis by ortho-olfactory evaluation. Both intake routes demonstrated transfer of limonene to milk, but the respiratory route transferred limonene with greater efficiency than the oral route. Moreover, according to the protocol used in this study, a short period of respiratory exposure induced a slightly higher limonene content in milk compared with oral exposure. As to the fate of limonene during cheesemaking, an important part of it was lost into the whey, perhaps through volatilization. The differences between milk and cheese tended to dissipate in curd and fresh cheese and disappeared completely after 15 d of ripening. Finally, it was possible to distinguish between the 2 routes of limonene intake using sensory analysis, even though no direct relationship was identified between the different aroma profiles of milks and cheeses from the oral and respiratory groups and their respective limonene contents. Overall, our results expand current knowledge on the biological pathways of terpene transfer from feed to sheep milk and cheese, as well as on the role played by terpenes in the formation of aroma in these products. Our observations may contribute to future development of strategies for external control and better standardization of the presence of odor compounds in milk and cheese from dairy ruminants.


Assuntos
Queijo , Animais , Queijo/análise , Feminino , Lactação , Limoneno/análise , Leite/química , Odorantes/análise , Projetos Piloto , Ovinos , Proteínas do Soro do Leite/análise
5.
J Dairy Sci ; 105(5): 4393-4409, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35248380

RESUMO

The present work aimed to investigate the effects of nucleotide oral administration on oxidative stress biomarkers, immune responses, gut morphology, serum biochemical parameters, and growth performance in calves from birth to 25 d of life. A total of 40 male Holstein Friesian calves were randomly divided in 2 groups. All the calves were born and reared on the same commercial dairy farm. They were fed the same colostrum, milk replacer, and calf starter. Five grams/head of an additive were orally administered with a syringe directly in the mouth to calves of the nucleotide group (NG). The additive contained 74.12 g/100 g of nucleic acids from hydrolyzed yeast, and 75.38% was free nucleotide sodium salt. The other group represented the negative control (CG). At 25 d of life all of the calves were slaughtered. Calves supplemented with nucleotides had a higher final live weight and improved average daily gain, which was associated with better efficiency of nutrient use. Oral nucleotide administration did not affect IgG absorption efficiency; however, NG calves showed greater duodenum villi length and higher crypt depth compared with CG. Oral nucleotide administration increased the activity of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) and the antioxidant capacity [ferric reducing antioxidant power and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) scavenging activity] both in plasma and in liver. An enhanced ability of cells to counter reactive oxygen species- and reactive nitrogen species-mediated damage was also observed in peripheral blood mononuclear cells from NG. The findings highlight the effectiveness of oral nucleotide administration, and potentially dietary supplementation of nucleotides, in boosting oxidative and immune status in newborn calves.


Assuntos
Ração Animal , Nucleotídeos , Administração Oral , Ração Animal/análise , Animais , Animais Recém-Nascidos , Antioxidantes , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Imunidade , Mucosa Intestinal , Leucócitos Mononucleares , Masculino , Estresse Oxidativo , Desmame
6.
J Dairy Sci ; 103(9): 8541-8553, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32684476

RESUMO

It is known that heat stress affects dairy cow performance in multiple ways: physiological, behavioral, reproductive, and productive. The aim of the present study was to determine if a threshold of temperature-humidity index (THI) exists for multiple milk production traits (milk yield, fat-corrected milk, protein and fat yield and percentage, energy-corrected milk, cheese production, and cheese yield) in Italian Brown Swiss dairy cows from the period 15 d before the day of the Italian Breeders Association test-day sampling. A 10-yr data set (2009-2018) containing 202,776 test-day records of 23,296 Brown Swiss cows was matched with the maximum THI. In all parities considered, no THI thresholds were observed for milk yield in Brown Swiss. In contrast, a THI threshold of 75 was identified for fat-corrected milk. No THI threshold was found for fat percentage, but fat yield showed the highest THI thresholds in cows of first and second parity. Protein yield and cheese production were affected by heat stress with average THI threshold of 74. The THI thresholds identified indicate that the Brown Swiss breed has higher thermal tolerance versus literature values reported for Holstein cows. As THI rises, Brown Swiss cows tend to produce the same volume of milk, but with a decreasing quality with regard to components. Further study is necessary to estimate the genetic component of heat tolerance, in Brown Swiss cattle, considering that the correct estimation of THI thresholds represents the first step to identify components that could be included in selection procedures.


Assuntos
Doenças dos Bovinos , Bovinos/fisiologia , Transtornos de Estresse por Calor/veterinária , Umidade , Lactação/fisiologia , Leite/fisiologia , Animais , Feminino , Temperatura Alta , Itália , Paridade , Gravidez , Temperatura , Termotolerância
7.
Asian-Australas J Anim Sci ; 26(11): 1637-43, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25049752

RESUMO

The present work describes the effect of slaughtering age on horse carcass traits and on meat quality. Eighteen male Italian heavy draught horse (IHDH) breed foals were employed in the study. Soon after foaling they were randomly subdivided in 3 groups according to 3 age at slaughtering classes: 6 months old, 11 months old and 18 months old. Live weight, hot carcass weight and dressing percentage of each animal were recorded. After slaughtering, meat samples were collected from Longissimus Dorsi muscle between 13th and 18th thoracic vertebra of each animal and then analyzed. The right half carcass of each animal was then divided in cuts. Each one was subdivided into lean, fat and bones. Then, the classification of the lean meat in first and second quality cuts was performed according to the butchers' customs. Older animals were characterized by a lower incidence of first quality cuts (p<0.01) on carcass. Younger animals showed greater content in protein (p<0.01). Fatty acid profile showed an increasing trend of PUFA connected to the increasing of slaughtering age (p<0.05). The unsaturation index of intramuscular fatty acids was not affected by slaughtering age, confirming that horse meat, if compared to beef, is more suitable from a nutritional point of view. Season influenced reproduction, birth as well as production aspects of this species. The different slaughtering age could represent the way to produce meat of IHDH foals during the entire year without change in the qualitative standard expected by consumers.

8.
J Dairy Sci ; 95(10): 5770-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22901483

RESUMO

The aim of this work was to study, using Wood's model, the lactation curve in Italian Heavy Draft horse (IHDH) mares, both for milk yield and composition. Interest in mare's milk has grown for use in human nutrition, as a substitute for human and cow milk for premature newborns and allergic children. For this study, 7 IHDH mares were used. Milk yield was evaluated from d 15 to 180 postpartum (every 15 d). Wood's lactation model was used to describe milk yield, fat, protein, and lactose lactation curves in the first 180 d in milk (DIM), with a prediction to 210 DIM. Mean values recorded across the considered lactation period for milk yield and constituents were 16.11 kg of milk/d, 11.38 g of fat/kg, 15.54 g of protein/kg, and 69.72 g of lactose/kg. The lactation curve showed a peak at 69 DIM, with a persistence index of 6.26. Fat (g/kg) and protein (g/kg) lactation curves decreased during the lactation period; instead, the lactose (g/kg) curve increased from the first to the last DIM. The coefficient of determination values indicated a good model fit by Wood's model application to IHDH mare lactation. The research showed good aptitude of a heavy horse breed, such as IHDH, for milk production.


Assuntos
Cavalos/fisiologia , Lactação/fisiologia , Animais , Gorduras/análise , Feminino , Lactose/análise , Leite/química , Leite/metabolismo , Proteínas do Leite/análise , Modelos Biológicos , Período Pós-Parto/fisiologia
9.
Asian-Australas J Anim Sci ; 25(12): 1775-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25049544

RESUMO

The aim of the present work was to investigate how colour changes of foal meat can vary after thawing out in relation to the slaughtering age of the horses and to the post-thawing time. Eighteen Italian Heavy Draught Horse (IHDH) foals were used for the trial. They were subdivided in three groups according to their slaughtering age (6, 11 and 18 months). Two different surfaces were investigated for each sample: a fresh cut surface (daily renewed cutting surface: DRCS), and not-renewed cutting surface (NRCS). The redness of both investigated surfaces increased with slaughtering age (p<0.01). Moreover, this parameter decreased during post-thawing time (p<0.01) only on the NRCS, probably due to the myoglobin oxidation processes. Colour is an important visual cue denoting perceived quality by consumers. So, by a chromatic perspective the thawed meat of IHDH foals slaughtered at 6 and 11 months proved to be that which best meets the market requirements.

10.
Animal ; 13(4): 888-896, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30134996

RESUMO

Supplementation with copper (Cu) improves deer antler characteristics, but it could modify meat quality and increase its Cu content to levels potentially harmful for humans. Here, we studied the effects of Cu bolus supplementation by means on quality and composition of sternocephalicus (ST) and rectus abdominis (RA) muscles (n=13 for each one) from yearling male red deer fed with a balanced diet. Each intraruminal bolus, containing 3.4 g of Cu, was administered orally in the treatment group to compare with the control group. Meat traits studied were pH at 24 h postmortem (pH24), colour, chemical composition, cholesterol content, fatty acid (FA) composition, amino acid (AA) profile and mineral content. In addition, the effect of Cu supplementation on mineral composition of liver and serum (at 0 and 90 days of treatment) was analysed. No interactions between Cu supplementation and muscle were observed for any trait. Supplementation with Cu increased the protein content of meat (P<0.01). However, Cu content of meat, liver and serum was not modified by supplementation. In fact, Cu content of meat (1.20 and 1.34 mg/kg for Cu supplemented and control deer, respectively) was much lower in both groups than 5 mg/kg of fresh weight allowed legally for food of animal origin. However, bolus of Cu tended to increase the meat content of zinc and significantly increased (P<0.05) the hepatic contents of sodium and lead. Muscles studied had different composition and characteristics. The RA muscle had significantly higher protein content (P<0.001), monounsaturated FA content (P<0.05) and essential/non-essential AA ratio (P<0.01) but lower pH24 (P<0.01) and polyunsaturated FA content (P=0.001) than the ST muscle. In addition, RA muscle had 14.4% less cholesterol (P=0.001) than ST muscle. Also, mineral profile differed between muscles with higher content of iron, significantly higher (P<0.001) content of zinc and lower content of calcium, magnesium and phosphorus (P<0.05) for ST muscle compared with RA. Therefore, supplementation with Cu modified deer meat characteristics, but it did not increase its concentration to toxic levels, making it a safe practice from this perspective. Despite the lower content of polyunsaturated FA, quality was better for RA than for ST muscle based on its higher content of protein with more essential/non-essential AA ratio and lower pH24 and cholesterol content.


Assuntos
Cobre/administração & dosagem , Cervos/fisiologia , Suplementos Nutricionais , Carne , Músculo Esquelético/efeitos dos fármacos , Ração Animal/análise , Animais , Dieta , Masculino
11.
Equine Vet J ; 50(4): 493-497, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29265484

RESUMO

BACKGROUND: Catecholamines are among the most frequently investigated parameters for studying sympathoadrenal activity in response to stress conditions. OBJECTIVES: To evaluate basal plasma concentrations of catecholamines (adrenaline, noradrenaline and dopamine) in healthy donkeys. STUDY DESIGN: Cross-sectional study. METHODS: Catecholamine concentrations from 440 Martina Franca donkeys were determined: 269 females and 171 entire males, aged from 4 months to 24 years. Animals were subdivided into four age categories: under 12 months old (64 males and 54 females), from 13 to 36 months (56 males and 75 females), from 37 to 120 months (49 males and 80 females) and over 120 months (24 males and 38 females). Indwelling jugular catheters were inserted at least 12 h before drawing blood. The data set was subjected to analysis of variance considering age, sex and the two-way interaction between them as independent variables. Pearson's correlation coefficients between the three catecholamines were evaluated. RESULTS: Confidence intervals (CI) for noradrenaline concentration ranged between 239.98 and 255.07 ng/L (mean 247.52 ng/L), for adrenaline between 129.27 and 137.90 ng/L (mean 133.59 ng/L), dopamine concentrations between 149.62 and 160.80 ng/L (mean 155.21 ng/L) and noradrenaline/adrenaline ratio between 1.91 and 2.05 (mean 1.98). Catecholamine plasma concentrations were not influenced by sex. Donkeys older than 37 months had lower adrenaline and noradrenaline plasma concentrations (P<0.001) and higher noradrenaline/adrenaline ratios (P<0.01) than younger animals. MAIN LIMITATIONS: Indwelling catheters and blood drawing procedures may have influenced catecholamine levels. CONCLUSIONS: Catecholamine concentrations were established within a large group of healthy Martina Franca donkeys.


Assuntos
Catecolaminas/sangue , Equidae/sangue , Envelhecimento , Animais , Estudos Transversais , Feminino , Masculino , Valores de Referência
12.
Meat Sci ; 134: 128-134, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28783609

RESUMO

This work aimed to evaluate the effect of suckling technique and slaughter age on Martina Franca donkey meat quality. Twenty Martina Franca male foals were involved in the trial. Foals naturally assumed colostrum within 4h from birth. Afterwards, 10 foals were partially artificially suckled (AS), and 10 foals were naturally suckled (NS). All the foals were weaned at 180d, then housed indoors and fed the same diet. Ten donkeys were slaughtered at 12months and the other 10 at the age of 18months. Samples of Longissimus thoracis et lumborum (LTL) were taken from each foal for chemical analysis, then rheological parameters, oxidative profile, colorimetric parameters and fatty acid profile were assessed. Older donkeys (18months) fed with natural milk presented the highest intramuscular fat (IMF) and meat protein content. From a dietary view point, IMF acid composition showed a more favourable profile in meat from artificially-reared donkeys compared to naturally-suckled ones.


Assuntos
Ração Animal/análise , Equidae , Carne/análise , Fatores Etários , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Feminino , Qualidade dos Alimentos , Masculino , Leite , Músculo Esquelético/química
13.
J Anim Sci ; 91(6): 2920-30, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23482573

RESUMO

The aim of the present work was to evaluate the effects of 2 different packaging films on chemical, physical, and microbiological variables in veal calf meat. Slices from the right half carcass were sampled from each calf: 8 were packaged with Cryovac film (25 µm thick) and 8 were packaged with Weegal film (45 µm thick). In both packaging types, the same gas mixture was used. The samples were analyzed at these postpackaging times: 0, 2, 4, 6, 8, 10, 12, and 14 d. Chromatic patterns, water holding capacity (WHC), cooking loss, drip loss, protein oxidation, and hydroperoxide concentration were influenced by the packaging type (P < 0.001). Moreover, during the postpackaging time the WHC decreased but oxidative reactions increased (P < 0.001). The film that showed better characteristics in packaging of veal calf meat was the Weegal, characterized by decreased gas permeability due to its ability to reduce and delay chemical and physical alterative processes.


Assuntos
Microbiologia de Alimentos , Embalagem de Alimentos , Carne/análise , Carne/microbiologia , Animais , Bovinos , Conservação de Alimentos , Gases/análise , Masculino , Fatores de Tempo
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