Genetic parameters of production and reproduction traits of Egyptian buffaloes under subtropical conditions.

This research was aimed to investigate the production and reproduction traits and their genetic parameters of Egyptian buffaloes under subtropical environment. Heritability, phenotypic, and genetic parameters were estimated for productive and reproduction traits of first parity This study revealed the averages TMY, 305-dMY, LL, BW, DP, SP, CI, and AFC were 2260, 2150 kg, 271 days, 38.63 kg, 210.50 days, 195.20 days, 586.86 days, and 36.61 months, respectively. The heritability estimates for productive traits of the first lactation were 0.61, 0.52, 0.47, 0.20, and 0.23 for TMY, 305-dMY, LL, DP, and BW, respectively. Heritability estimates for reproductive traits SP, CI, and AFC were 0.07, 0.09, and 0.35, respectively. Genetic correlations of most of the investigated first parity traits were positive, with an exception of DP. The genetic correlation was negative between SP and BW, and between AFC and LL. Phenotypic correlations of the first parity among all investigated traits were positive except between DP and TMY, 305-dMY, LL, BW, and AFC. High and moderate heritability estimates indicated that the opportunity of genetic upgrading of these parameters could be achieved owing to sire selection. Selection for high milk yield will be associated with genetic improvement in lactation period and birth weight.

Growth, carcass parameters, biochemical and oxidative stress indices, and meat traits of duck breeds under different stocking densities.

This investigation was aimed to inspect if there is an influence of various stocking density on growth, carcass parameters, blood indices, and meat traits of Muscovy and Mallard ducks. One hundred twenty-six 1-day-old of each Muscovy and Mallard ducks were randomly allocated into three experimental groups with different stocking density. Group one (SD1) was 5 ducks/m2, while group 2 (SD2) was 7 ducks/m2 and group 3 (SD3) was 9 ducks/m2. The growth, carcass parameters, meat quality, blood indices were calculated. Body weight of SD1 was 18 and 4.5% heavier than SD2, while, it was 29.5 and 12% heavier than SD3 of Muscovy and Mallard duck breeds, respectively. SD3 possessed the highest levels of, H/L, ALT, AST, LDL, VLDL, and MDA with the lowest levels of lymphocyte, SOD,GSH, GPX, C3, total antioxidant capacity and IGG of both ducks' breeds. The carcass weight decreased by 40 and 15% from SD1 to SD3 in Muscovy and mallard ducks, respectively. The dressing % was highest at SD1 (84 and 83%) when compared with SD3(71and80%) of Muscovy and Mallard ducks, respectively. Cooking loss was 20 and 16% greater in group three when compared with group one in Muscovy and Mallard ducks, respectively. In conclusion ducks raised in low SD possessed the best performance with better welfare.

Reproductive Performance and Culling Rate of Purebred Holstein Cows and Their Crosses With Fleckvieh and Brown Swiss Cows Under Subtropical Conditions.

This study aimed to elucidate the reproductive performance of purebred Holstein (HO) cows with their crosses with Fleckvieh (FV) and Brown Swiss (BS) cows under subtropical conditions. A total of 677 cows [487 HO, 104 HO × FV (HFV); 50% FV and 50% HO and 86 HO × BS (HB); 50% BS and 50% HO] were enrolled in this study. Pure HO cows had significantly greater service per conception (S/C; 3.69), days open (147.9 days), and calving interval (449.6 days), than the HFV (2.89, 116.7, and 407.4 days, respectively) and HB (3.07, 134.3, and 434.2 days, respectively) crossbred cows. At day 28, the conception percentage was significantly greater among HFV crossbred cows vs. pure HO cows [crude odds ratios (COR) = 2.16], but embryonic loss, abortion percentage, calving difficulty, and retained placenta percentage were similar (p > 0.05) among pure HO cows and their crosses. HFV crossbreds had significantly lower incidence of endometritis (COR = 0.70, p = 0.035), mastitis (COR = 0.69, p = 0.015), and ketosis (COR = 0.53, p = 0.004) vs. other cows. HB and pure HO cows had a similar incidence of mastitis, lameness, and ketosis (COR = 0.76, 0.75, and 0.81; p = 0.223, 0.468, and 0.492, respectively). HFV crossbred cows had a lower risk of culling rate than HB crossbred cows. In summary, HFV cows demonstrated the best reproductive performance in terms of S/C, days open, calving interval, conception at 28 days, mastitis percentage, ketosis percentage, and endometritis.

Potential impact of stocking density on growth, carcass traits, indicators of biochemical and oxidative stress and meat quality of different broiler breeds.

The aim of the current study to investigate the potential impact of different stocking densities on growth performance, carcass traits, indicators of biochemical and oxidative stress and meat quality of Arbor Acres and Ross-308 broiler breeds to recommend the better stocking density with low production cost simultaneously with high quality. A total of 312 one-day old of each Arbor Acres broiler and Ross-308 were randomly classified into 3 experimental groups with different stocking density, each of 6 replicates. The first group (SD1) was 14 birds/m2 (28 kg/m2), while the second group (SD2) was 18 birds/m2 (36 kg/m2) and the third group (SD3) was 20 birds/m2 (40 kg/m2). The growth performance, carcass traits, meat quality hematological and biochemical parameters were measured. SD3 group possessed the lowest body weight. Alanine transaminase in Arbor Acres was 15 and 14% higher in SD3 when compared with SD1 and SD2, respectively. While, was 21 and 20% of Ross-308, respectively. SD3 revealed the highest values of cholesterol, TG, MDA, and LDL of both breeds when compared with SD1 and SD2, with the lowest levels of HDL, GPX, and IGG. Birds of SD3 was the nastiest carcass weight 873 (P = 0.000) and 1,411.60 g (P = 0.000); dressing percentage 63.07 (P = 0.000) and 75.83% (P = 0.000); breast weight 513.10 g (P = 0.000) and 885.50g (P = 0.000); thigh weight 359.90 g (P = 0.000) and 526.08 g (P = 0.000) when compared with SD1 and SD2 of Arbor Acres and Ross-308, respectively. The dressing % of SD1 and SD2 was approximately 19% better than that of SD3 of Arbor Acres, while it was 4% of Ross-308. The cooking loss and drip loss of breast and thigh muscles were higher in SD3 of both breeds. Moreover, SD3 possessed the highest bacterial count. In conclusion birds reared in medium stocking density revealed better performance and welfare than high density but similar to low density. Therefore, from the economic point, medium density was the best.

Immunological Responses and the Antioxidant Status in African Catfish (Clarias gariepinus) Following Replacement of Dietary Fish Meal with Plant Protein.

African catfish (Clarias gariepinus) were subjected to a 30-day feeding trial to determine the appropriateness of using plant protein (PP) (soybean and sunflower meal) as a fishmeal (FM) replacement in the diet and its effects on immune status, antioxidant activity, pituitary adenylate cyclase-activating polypeptide (PACAP) gene expression, and disease resistance. A total of 150 C. gariepinus (51.01 ± 0.34 g) were randomly distributed among five groups in triplicate. Five experimental diets were formulated to replace 0 (control), 33.5, 50, 66.5, and 100% FM with soybean and sunflower meal to form the experimental diets (R0, R33.5, R50, R66.5, and R100, respectively). After 30 days, the diet containing PP for FM had no significant impact on total, and differential leukocyte counts determined at the end of the feeding period. The total globulin concentration showed significantly greater differences in the following order R0 > R33.5 > R50 > R66.5 > R100. The R0 group had the highest concentration of serum γ-globulin, while R100 had the lowest concentration. The antioxidant status complements 3 (C3), lysozyme activity (LYZ), and antiprotease activity were not significantly different between R0, R33.5, and R50 groups, while they were significantly lower in R100. The serum nitric oxide activity (NO) exhibited significantly greater differences in the following order R0 > R33.5 > R50 > R66.5 > R100. PACAP was significantly higher in the R33.5 group. The highest cumulative mortality caused by Aeromonas sobria was recorded in the R100 group (60%) and the lowest in the R0 group (30%). In conclusion, the results indicate that the immunological responses and antioxidant status of C. gariepinus were not affected when they consumed a diet with FM replaced by up to 50% with PP (SBM and SFM) with methionine and lysine supplementation, but total globulin, NO, and cumulative mortality were impaired with a diet containing a 100% FM replacement.

Growth, Hemato-Biochemical Parameters, Body Composition, and Myostatin Gene Expression of Clarias gariepinus Fed by Replacing Fishmeal with Plant Protein.

In this study, we evaluated the consequences of replacement of fishmeal with plant protein sources (soybean and sunflower meal) on fish growth parameters, haemato-biochemical factors, body composition, and myostatin gene expression of Clarias gariepinus. A total of 150 C. gariepinus were organized in glass aquaria into five investigational groups, with each group in triplicate (30 fish/group; 10 fish/replicate). Group 1 was fed a control diet (15% fishmeal). The other groups were fed diets where fishmeal was replaced gradually with plant protein, with 10% fishmeal in the second group (D1), 7.5% fishmeal in the third group (D2), 5% fishmeal in the fourth group (D3), and 0% fishmeal in the fifth group (D4). There were no significant differences regarding growth performances and body composition among the groups, except that the feed conversion ratio was improved in D4. The different diet types did not affect hematologic parameters and blood indices. Serum growth hormone and amylase levels also revealed no significant (p = 0.09 and 0.55, respectively) differences among the groups, while serum lipase levels decreased significantly (p = 0.000) due to partial (D2) or complete (D4) substitution of fishmeal with plant protein. The replacement of fishmeal had no effects on liver (p = 0.51) and kidney functions (p = 0.34). However, D4 showed the best profit and economic efficiency compared to the other groups. Altogether, we concluded that substitution of fishmeal with plant protein sources is economically beneficial and may be without any adverse effects on growth parameters, body composition, or hematologic and biochemical parameters, but with the addition of synthetic amino acids.

Principal component analysis of breeding values for birth weight milk and reproductive traits of the Egyptian buffalo.

This study was conducted to estimate the genetic parameters and breeding values for birth weight (BW) and reproductive and milk traits of the Egyptian buffalo. Moreover, the relationship among the estimated breeding values was analyzed using the principal component analysis, and selection index was constructed to improve performance. A total of 65,734 records of 2426 buffalo cows calved from 1980 to 2018 were collected from five buffalo experimental herds to estimate the genetic parameters and breeding values and then standardized for use in the principal component analysis with covariance matrix. The estimated heritability values were low for BW, total milk yield (TMY), gestation length (GL), days open (DO), calving interval (CI), calving ease (CE), and age at first calving (AFC), but they were moderate for lactation period (LP). The repeatability estimates were very low for DO and CI but were low for BW, GL, and CE, whereas they were moderate for TMY and LP. Of eight principal components (PCs), four PCs had > 1 eigenvalues, and the total variance explained was 70.37%. The variances explained for PC1, PC2, PC3, and PC4 were 25.71%, 18.20%, 13.28%, and 13.18%, respectively. The standardized estimated breeding values of CI and DO, TMY and LP, GL and CE, and BW and AFC correlated with PC1 (0.915 and 0.925), PC2 (0.760 and 0.758), PC3 (- 0.622 and 0.567), and PC4 (0.710 and 0.438), respectively. These results suggest that BW and reproduction traits would respond slowly to selection, whereas production traits would respond faster, and the uses of PCs depend primarily on the selection purpose that could be used in the genetic improvement programs of the Egyptian buffalo instead of the traditional selection index.

Does light intensity affect the behavior, welfare, performance, meat quality, amino acid profile, and egg quality of Japanese quails?

The current study aimed to explore the impact of different light intensities on behavior, welfare, performance, meat quality, amino acid content, and egg quality of Japanese quails. A total of 600 1-day-old Japanese quail chicks were used (300/batch). Chicks were homogeneously classified into 3 groups (each of 100); low (10 lux), moderate (50 lux). and high light intensity (250 lux) groups. There was a significant effect (P < 0.05) of light intensity in most of the Japanese quails' behaviors. Quails reared on low light intensity showed the lowest behavior of feeding, drinking, flying, and feather picking, while the highest behaviors were preening, dust bathing, leg and wing stretching, and body shaking when compared with the other groups. Moreover, they had the better welfare (lowest H/L ratio and corticosterone levels). Quails of low light intensity groups possessed the heaviest body weight (145.17 g, P = 0.000) with the lowest daily feed intake (14.17 g) but with the best feed conversion ratio (3.39%, P = 0.000). Moreover, they had the heaviest slaughter (132.47 g, P = 0.000) and carcass weight (109.29 g, P = 0.000) and carcass yield (75.37%, P = 0.000) when compared with the others groups. Muscles of quails (both of pectoral and thigh) kept under low light intensity revealed the highest percentage of lightness, yellowness, and water-holding capacity with the lowest percentage of cooking loss, thiobarbituric acid reactive substances, and some amino acids. They also had the heaviest egg weight (11.24 g, P = 0.000) with the best external and internal egg-quality grades (P < 0.05). Consequently, low light intensity is suggested for improving quail's welfare, performance, and reproduction, while the high light intensity had a detrimental effect on both welfare and performance.

The effect of rosemary extract and lactic acid on the quality of refrigerated broiler fillets.

The current study investigated the effect of rosemary extract (0.2% RE) and lactic acid (1% LA) on some freshness, bacterial parameters and formation of biogenic amines during refrigeration of broiler fillets. Ninety broiler fillet samples were divided into three groups (each 30). The control group was dipped in sterile distilled water, while the RE and LA groups were dipped in rosemary extract 0.2% (w/v) and lactic acid 1% (w/v), respectively. Sensory evaluation, pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), total psychrotrophic and Enterobacteriaceae counts were performed at zero time and at 3 days interval until the group were rejected from sensory analysis. Organoleptic scores were unacceptable after the 9th, 12th and 15th day of refrigeration in control, RE and LA groups, respectively. TVB-N was the lowest in LA group (3rd day; 4.36 ± 0.12, 6th day; 5.62 ± 0.7 and 9th day; 10.13 ± 0.98) when compared with the RE and control groups. Moreover, TBARS was the highest in the control group (3rd day; 0.22 ± 0.06, 6th day; 0.39 ± 0.07 and 9th day; 0.78 ± 0.09) when compared with the RE and LA groups. LA group showed the lowest number of psychrotrophic bacteria during refrigeration period when compared with the other groups. Enterbacteriaceae was detected at zero, 3rd and 6th day in control, RE and LA groups, respectively. This study concluded that dipping in LA 1% or RE 0.2% reduce the psychrotrophic and Enterobacteriaceae bacteria of broiler fillet and increased the acceptability of refrigerated fillet, decreased the biogenic amines formation and rancidity. Therefore, broiler fillets dipped in RE 0.2% or LA 1% can be used up to 12 or 15 days when refrigerated at 4 °C.

Performance, carcass traits, meat quality and amino acid profile of different Japanese quails strains.

Poultry production is considered one of the prospective opportunities to accomplish sustainable and quick production of superior protein to challenge the growing mandate for animal protein. Therefore, this study was aimed to explore the difference on growth performance, carcass traits, meat quality and amino acid profile of different Japanese quails strains. A total of 480 quail chicks of four different plumage colors (120 of each white, golden, gray and brown) were collected after hatching. At 6 week of age, birds were stunned and decapitated to determine the physical meat quality, thiobarbituric acid reactive substances and amino acid profile. White quails had the highest weight of slaughter, carcass, dressing, carcass yield, liver, gizzard, heart and spleen (197.27 g, 169.27 g, 91%, 82%, 6.63 g, 6.53 g, 2.27 g and 0.40 g, respectively). Also, they had the highest PhU, lightness, yellowness and water holding capacity with the lowest level of redness, cooking losses and thiobarbituric acid in pectoral (6.28, 46.40, 12,46, 22.17, 9.20, 19.21 and 0.44, respectively) and thigh muscles (6.37, 42.30, 11.51, 26.01, 10.12 and 0.93, respectively). Moreover, they possessed the highest level of all essential (11.68 and 10.16 g/100 g protein in pectoral and thigh muscles, respectively) and non essential amino acids (13.27 and 12.54 g/100 g protein in pectoral and thigh muscles, respectively). Therefore, the current study revealed that white quails had the heaviest body weight with the best carcass traits and meat quality.

Growth performance, carcass characteristics, meat quality and muscle amino-acid profile of different rabbits breeds and their crosses.

Meat production efficiency can be enhanced by crossbreeding to capture heterosis. This study aimed to investigate the impact of rabbit genotype on growth performance, carcass traits, meat quality and amino acids profile. A total of 504 weaned rabbits from nine genotypes of full factorial crossing of New Zealand White (NZW), Californian (CA) and Rex (RX) were used. Longissimus thoracis et lumborum muscles were assessed for meat quality and amino acids profile. There were no differences between groups at weaning and 6weeks, but by 10weeks differences were significant (P<0.001) and the numerically heaviest groups were CA×RX and RX×NZW (1970g, P<0.001) with to some extent better amino acids profile. In conclusion, RX growth performance was improved by crossing CA sire with RX dam and RX sire with NZW dam and to have dual purpose breed with better growth performance without hazard on carcass and meat quality. CA×RX and RX×NZW had the heaviest body weight at 10weeks of age and highest body weight gain during the whole finishing period.

The effect of stillbirth on reproductive and productive performance of pure Egyptian buffaloes and their crosses with Italian buffaloes.

High rates of stillbirth in buffaloes are not only emotionally and economically undesirable but also contrary to animal welfare practices. Thus, this study was aimed to investigate risk factors for stillbirth and analyze its effects on the productive and reproductive performance of pure Egyptian buffaloes (PE) and their crossing with the Italian buffaloes (F1 crosses 50%PE and 50%Italian buffaloes and Back cross (BC) 75%PE and 25%Italian buffaloes) under subtropical environmental conditions. Records of a total of 8388 (5169PE, 1494F1 and 1725BC) were used in this study with 1965 actual first parity records (489, 621 and 855, respectively). The incidence of stillbirth in the farms was 12.4% and 9.2% for primiparous and multiparous cows, respectively. It did not vary among seasons or due to gestation length, calf sex and conception after first insemination in BC buffaloes. BC buffaloes with stillbirths had shorter gestation length, first service post-partum and longer dry period (300.32, 33.67 and 207.05days, respectively) compared to those live births (311.28, 33.90 and 140.22days, respectively), implying that these animals could better adapt to the tough circumstances following stillbirth as reproductive indices were only slightly affected due to stillbirths. Contrarily, the productivity and reproductive performance of PE buffaloes were markedly decreased after stillbirth. Their milk yield, average daily milk yield and lactation length were decreased by 6.27, 10.29 and 6.36%, respectively after stillbirth, while days open, dry period and first service post-partum were increased after stillbirth by 14.28, 13.54 and 12.78%, respectively. The results from this study suggest that producers should be promoted to increase the BC animals in their farms with the intention of increasing milk production and ensure superior reproduction efficiencies with lower stillbirth incidence.

Maternal and non-maternal factors associated with late embryonic and early fetal losses in dairy cows.

Defining factors associated with embryonic and/or fetal losses will be helpful in overcoming such problem, either by adjusting conditions or applying therapeutic approaches to high-risk cows. The objective of this study was to investigate the association between a number of maternal and non-maternal factors and the risk of late embryonic (LED) and early fetal death (EFD) in dairy herds. Additionally, we investigated the effect of treating pregnant cows either with GnRH on day 26 post-insemination, or GnRH on day 26 plus CIDR insertion between days 26 and 33 post-insemination, on the risk of LED/EFD. From 3826 pregnancies, diagnosed at day 30 post-insemination, 851 cows lost the pregnancy by day 70 post-insemination. A mixed-effects logistic model was constructed to assess the effect of cow breed, calving difficulty, postpartum problems, lactation number, days in milk, insemination number, actual 305-day milk production, temperature humidity index (THI) at insemination, estrus synchronization protocols, and other factors, on the risk of LED/EFD. Our findings indicated that Holstein X Brown Swiss crossbreed cows had a lower risk for LED/EFD than Holstein cows (P < 0.05). Cows that had postpartum problems, were inseminated for the first time, produced more milk, or were inseminated at THI ≥75, recorded higher risks of LED/EFD (P < 0.05). Calving difficulty, lactation number, and synchronization protocols were not found to be associated with LED/EFD. Moreover, treatment of the pregnant cows with GnRH on day 26 post-insemination plus CIDR insertion between days 26 and 33 post-insemination decreased the risk of LED/EFD. In conclusion, cows that had postpartum problems, were inseminated early postpartum, produced higher milk, and/or were inseminated at high THI, were under higher risk of LED/EFD. Treating such cows with GnRH on day 26 plus CIDR insertion between days 26 and 33 may decrease the possibility of the LED/EFD.

The potential effect of temperature-humidity index on productive and reproductive performance of buffaloes with different genotypes under hot conditions.

The current study was aimed to investigate the impact of THI on productive and reproductive indices of PE and F1 crosses (50% PE and 50% Italian buffaloes) and back crosses (BC) (75% PE and 25% Italian buffaloes) under hot conditions. In this study, 8385 records used PE (1914, 1518, and 1737), F1 (387, 447, and 657), and BC (495, 585, and 645) for low, medium, and high THI, respectively. The high THI reduced the conception rate after first insemination in PE, F1, and BC ((odds ratio, OR) = 1.187, P = 0.007; 2.361, <0.0001 and 1.603, <0.0001, respectively) when compared with low THI. But, stillbirth and calving condition were not significantly influenced by different THI levels in BC and F1. BC was more bearable to the harsh environment; they possessed the highest incidence of conception after first insemination (72.70, 72.60, and 62.40%), producing live calves (98.50, 100, and 99.40%) with easy calving condition (98.50, 100, and 99.40%) when compared to PE and F1 at different levels of THI, respectively. The average daily milk yield and peak of milk production were decreased in PE (4.02 and 5.12%), BC (13.33 and 10.95%), and F1 (25.29 and 12.20%) from low to high THI. However, BC revealed no significant changes in days open, dry period, calving interval, gestation length, service per conception, and the first service post-partum at different levels of THI when compared with PE and F1. Therefore, rearing BC is recommended for improving buffalo productive and reproductive performance under hot conditions.

Impact of three THI levels on somatic cell count, milk yield and composition of multiparous Holstein cows in a subtropical region.

In Egypt, cow's milk represents 52.11% of the total milk production. Climatic condition is mainly expected to impact the welfare and productive performance of livestock animals. Thus, we aimed to explore the impact of temperature-humidity index (THI) on somatic cell count (SCC), milk production and composition on daily milk test records (33600) of Holstein cows under subtropical Egyptian conditions with different levels of THI. Our results revealed that daily milk yield and composition (fat%, protein %, yielded fat, yielded protein and the percentage of lactose) were higher in low THI (31.91kg, 3.91%, 3.22%, 418kg, 349kg and 4.20%, respectively) when compared with high THI. SCC significantly increased 36% from low to high THI. In addition to, it was increased with advanced parities 231.11% from 2nd to 7th parities. At high THI level, SCC was negatively correlated with total MY (r=-0.12P<0.05), 305 MY (r=-0.16P<0.05), protein % (r=-0.15P<0.01), fat% (r=-0.14P<0.01) and lactose % (r=-0.26P<0.01). The current study concluded that dairy cows performance was better in most of the investigated parameters at low THI than those in high THI. Thus, indicating a detrimental effect of THI on both welfare and economic return.

Reproductive performance of Brown Swiss, Holstein and their crosses under subtropical environmental conditions.

Selection has been emphasized for increasing production traits with ignoring the fertility traits, which leads to a general loss of reproductive fitness. The aim of this study was to evaluate the reproductive performance of the pure Brown Swiss (BS), Holstein (HO), their first-generation crossbred (F1), and backcross (BC) cows under subtropical Egyptian conditions. The reproductive performance and health traits were measured in the pure BS, HO, their F1, and BC crossbred, in addition to investigating the impact of temperature-humidity index level (THI) on reproductive traits. Brown Swiss and her F1 had a better reproductive efficiency and health traits than in HO and BC. They possess a higher conception (34.1% and 36.9%, respectively) and pregnancy rates (32.8% and 31.1%, respectively), a shorter calving interval (401 and 420 days, respectively), and a lower average insemination per parturition (3.18 and 3.45, respectively), with a lower incidence of metritis (14.1% and 14.6%, respectively). Moreover, no difference has been detected in the fertility of BS with different THI levels, whereas F1 was slightly affected by increasing THI, especially for conception rate which declined from 43.1% at low to 24.1% at high THI. But the pregnancy rate did not change with different levels of THI. Our results indicate that BS and her F1 have a better reproductive performance and adaptability than pure HO and BC under subtropical Egyptian conditions. Furthermore, milk yield of the F1 crossbred is comparable to that of the pure HO cows.

Do laying hens with keel bone fractures experience pain?

The European ban on battery cages has forced a change towards the use of non-cage or furnished cage systems, but unexpectedly this has been associated with an increased prevalence of keel bone fractures in laying hens. Bone fractures are acutely painful in mammals, but the effect of fractures on bird welfare is unclear. We recently reported that keel bone fractures have an effect on bird mobility. One possible explanation for this is that flying becomes mechanically impaired. However it is also possible that if birds have a capacity to feel pain, then ongoing pain resulting from the fracture could contribute to decreased mobility. The aim was to provide proof of concept that administration of appropriate analgesic drugs improves mobility in birds with keel fracture; thereby contributing to the debate about the capacity of birds to experience pain and whether fractures are associated with pain in laying hens. In hens with keel fractures, butorphanol decreased the latency to land from perches compared with latencies recorded for these hens following saline (mean (SEM) landing time (seconds) birds with keel fractures treated with butorphanol and saline from the 50, 100 and 150 cm perch heights respectively 1.7 (0.3), 2.2 (0.3), p = 0.05, 50 cm; 12.5 (6.6), 16.9 (6.7), p = 0.03, 100 cm; 20.6 (7.4), 26.3 (7.6), p = 0.02 150 cm). Mobility indices were largely unchanged in birds without keel fractures following butorphanol. Critically, butorphanol can be considered analgesic in our study because it improved the ability of birds to perform a complex behaviour that requires both motivation and higher cognitive processing. This is the first study to provide a solid evidential base that birds with keel fractures experience pain, a finding that has significant implications for the welfare of laying hens that are housed in non-cage or furnished caged systems.