Zealand White Breed Research Articles

The Comparative Study on Effect of Breed and Gender on Some Carcass Traits of New Zealand White and Dutch Rabbit Breeds

This study was designed to observe the effect of breed on some carcass traits of New Zealand White and Dutch rabbit breeds. In this study, 2 males and 8 female Breeder Rabbits from New Zealand White and Dutch rabbit breeds were purchased from a local farmer and allowed for breeding purposes by the ratio of 1:4 Male to Female in different cages. From the first filial generation, 80 kits were randomly selected after weaning at 21-25 days and grouped into A, B, C, and D. Groups A and C included males of New Zealand White and Dutch breeds, whereas B and D included females. Their live weight at 80 days was observed, and lastly, they were slaughtered to observe the effect of breed on carcass traits. Dutch breed males showed significantly higher (P<0.05) weaning weight, live weight, slaughter weight, carcass weight, boneless weight, bone weight and dressing percentage compared to New Zealand White males, while Dutch females also exhibited higher traits compared to New Zealand White females. The results indicated that Dutch rabbits had higher birth weight, weaning weight, live weight, slaughter weight, carcass weight, boneless weight, bone weight, and dressing percentage as compared with New Zealand White breeds.

Genetic Characterization of Myf5 and POU1F1 Genes in Different Egyptian Local Rabbit Breeds and Their Association with Growth Traits

Genetic characterization and its association with quantitative traits in local breeds are important tools for the genetic improvement and sustainable management of animal genetic resources. Myogenic regulatory factor 5 (MYf5) and POU class 1 homeobox 1 (POU1F1) are candidate genes which play important roles in growth and development of mammals. The present study aims to detect the genetic diversity of the MYf5 and POU1F1 genes in four local Egyptian rabbit breeds and their association with growth traits, using PCR-restriction enzyme (PCR–RFLP), PCR-single-strand conformational polymorphism (PCR–SSCP), and direct sequencing techniques. The results showed that MYF5 exon 1 was observed with two genotypes in Baladi Black (BB), Gabali (GB) and New Zealand White (NZW) breeds while APRI-line (APRI) presented one genotype. The genetic diversity of Myf5 exon 2 between breeds showed two genotypes in APRI compared to three in NZW and four genotypes in BB and GB breeds. The genetic diversity of the POU1F1 gene (intron 5 and partial cds) in different rabbit breeds was two genotypes in NZW and three genotypes in BB, GB, and APRI breeds with different frequencies for each genotype. Based on the statistically significant difference between genes genotypes and growth weight, the results suggested that the genotypes of Myf5 exon 2 (1 and 2) of the BB breed, Myf5 exon 2 genotype 2 of the APRI breed, and genotype 1 of Myf5 exon 1 and genotype 1 of POU1F1 of the NZW breed compared to genotypes for each gene can be considered candidate molecular markers associated with the improvement of growth traits in these breeds.

Growth, survival rate of New Zealand White, Dutch Rabbit and their crosses

Abstract. The aim of the study was to assess survival rate of crossbred New Zealand White and Dutch rabbit breed. A total of 16 mature rabbits of seven to nine months old, New Zealand White and Dutch were used for the study. Data obtained were subjected to analysis of variance ANOVA using SAS. The reproductive traits studied were litter size, litter birth weight, mean kit weight. The growth traits were: body weight, body length, ear length, chest circumference, hind limbs, thigh length, nose to shoulder and thigh circumference. The reproductive traits were significantly (P<0.05) affected by genetic group Pure and crosses. New Zealand White observed high litter size and litter birth weight at first, seventh, 14th and 21st day. Purebred Dutch had significant (P<0.05) high values for growth traits. The body weight 478.73±18.10, body length 33.12±0.42, ear length 9.10±0.09, chest circumference 18.24±0.45 and hind limbs 19.51±0.33 were significantly (P<0.05) high in crosses of Dutch x New Zealand White. Pre-weaning mortality and survival rate at weaning were 22.22% and 77.77% high in New Zealand White; 14.28% and 85.71% in Dutch and DUC x NZW; and 9.09% and 90.90% in NZW x DUC. In conclusion, New Zealand White x Dutch crosses demonstrated high survival rate and low pre-weaning mortality.

Fixing Collinearity Instability in Body Weight Estimation Based on Morpho-biometrical Traits of Rabbits Bucks

Morpho-biometric studies were conducted on 32 growing rabbit bucks comprising Chinchilla, New Zealand white and Dutch breeds to identify the estimation of body weight collinearity. The body weight and biometric traits taken were analyzed using statistical package for the Social Sciences (SPSS) version 16. Body weight and zoometrical factors had positive and highly significant bivariate relationships. The body weight and height at the withers showed the best relationship (0.826; p<0.01), whilst the foreleg and ear length showed the lowest correlation (0.542; p<0.05). Since none of the body measurements were greater than 10.00, the variance inflation factors (VIFs) displayed non-collinearity issues in all of the measurements. Tolerance (T) values greater than 0.10 in all of the same measurements served as confirmation of this. No collinearity was also evident in the eigenvalues of the correlation matrix, condition indices, or variance proportions. Body length was kept as the most crucial attribute for prediction among the variables. This study showed that there is no collinearity among selected morphometric traits. Stepwise multi-regression models showed that the best predictor of body weight was based on a combination of wither height, chest circumference, waist circumference, waist length, hind limb length, and head circumference (R2 and adjusted R2 =0.84). This research has the practical application that morphological indices can be utilized in the field to estimate body weight for selection and to estimate market values for rabbit bucks.

Osseointegration properties of domestic bioactive calcium phosphate ceramics doped with silicon

Abstract Introduction The relevance of this study lies in the fact, that today the search for biocompatible materials for the management of bone defects is of importance. Such materials could become an alternative to transplants. For the replacement of bone defects, two-phasic bioactive ceramics of hydroxyapatite and β-tricalcium phosphate is a very attractive biomaterial due to its excellent biocompatibility and osteoconductivity, but the results of its use are quite controversial due to insufficient bioactivity. The purpose of this work is to investigate the osseointegration properties of two-phase bioactive ceramics doped with silicon (HTdSi), both as a single component and a component in combination with platelet-rich fibrin, as well as in comparison with the well-known imported analogue – BIO, which consists of β-tricalcium phosphate, also as an independent component and a component in combination with platelet-rich fibrin. In the experiment, the rabbits of the New Zealand white breed at the age of 3 months and with an average weight of 2.5 kg were used. The terms of implantation are 30, 60, 90 and 180 days. The advantages of the domestic bio-composite are substantiated on the basis of clinical, radiological and histological studies. Material and methods In the experiment, the rabbits of the New Zealand white breed at the age of 3 months and with an average weight of 2.5 kg were used. The terms of implantation are 30, 60, 90 and 180 days. Results The osteointegration properties of two-phase bioactive ceramics doped with silicon (HTdSi), both as a single component and in combination with platelet fibrin, were investigated, as well as in comparison with the known imported analog - BIO, which contains β-tricalcium phosphate, both as a single component and in combination with platelet fibrin. Conclusions The advantages of domestic biocomposite are substantiated on the basis of clinical, radiological and histological studies.

Biological features of the formation of meat productivity of rabbits of chin-chilla breed depending on crossing with meat breeds

Rabbit breeding is a special branch of animal husbandry characterized by high fertility and growth intensity. The main way of intensification of rabbit farming involves such selection measures that adapt rabbit populations of keeping in industrial conditions, ensure high reproductive properties of female rabbits, preservation of rabbits in nests, high growth rate, fattening and meat qualities of animals. The research was conducted on the basis of the experimental rabbit farm of the Cherkasy Research Station of Bioresources of the National Academy of Sciences on the population of female chinchilla (Chinchilla) rabbits and males of the Gray giant rabbit (Gray giant rabbit), New Zealand white rabbit (New Zealand white rabbit) and young rabbits obtained from these three combinations. As the result of the conducted research, it was found that under the conditions of intensive production of rabbit meat, the reproductive qualities of female chinchilla rabbits in combination with males of the Gray giant and New Zealand white rabbits breeds increase, namely: high fertility – on 1.8–5.2 %; milk yield – on 1.8–7.4 %. The weight of the nest at weaning was probably (P < 0.001) higher in female rabbits of the combination Chinchilla x New Zealand white rabbit and was 5.29 ± 0.13 kg, which is 869 g more than the purebred peers of the chinchilla breed and 380 g more than the combination Chinchilla x Great giant rabbit. The best indicators of fattening and meat productivity were found in young rabbits of 1/2Chinchilla 1/2Gray giant rabbit and 1/2Chinchilla 1/2New Zealand white rabbit origin. The fattening indicators of the rabbits of these groups compared to the rabbits of the control group accordingly increased: live weight at 90 days of age – on 4.0 and 3.8 % (Р < 0.05); average daily increases – on 4.7 and 5.4 % (Р < 0.05; Р < 0.01); waist width – on 5.6 and 8.7 % (Р < 0.01). The research also revealed that the group of young rabbits 1/2Chinchilla 1/2New Zealand white rabbit by origin had a higher slaughter yield and the indicators of which exceeded and rabbits of the second group ( 1/2Chinchilla 1/2Gray giant rabbit on 3.6% and the first (Chinchilla) – on 4.1 %, and the expenses of feed per 1 kg of increase by group was 3.85 accordingly; 3.75; 3.7 kg. Crossbred rabbits 1/2Chinchilla 1/2New Zealand white rabbit and 1/2Chinchilla 1/2Gray giant rabbit according to this indicator prevailed over purebred peers (Chinchilla) on 2.6 and 3.9 %, accordingly.

INFLUENCE OF A HIGHLY POROUS CERAMIC IMPLANT BASED ON ZIRCONIUM OXIDE (ZRO2) ON BONE TISSUE REGENERATION

The purpose of this experimental work was to determine the regeneration ability of bone tissue due to modern bioceramics synthesized and obtained using the previously developed method of reactive spark plasma sintering (Spark Plasma Sintering-Reactive Synthesis, SPS-RS). The study was performed on 26 laboratory rabbits - females of the New Zealand White breed, divided into two groups. The evaluation of the regeneration of the burr hole after covering the defect with a bioceramic implant was performed by the method - (BMD) X-ray densitometry on days 7, 40, 210 after surgery. As a result of the study, there was a tight fixation of the implant in the area of ​​the bone tissue defect without its dislocation. There were no signs of osteoporosis and osteolysis in the surrounding bone tissues. And on the 210th day after the operation, according to densitometric data, the formation of dense bone tissue was observed. The use of a bioceramic implant makes it possible to immediately close large bone defects and to stimulate the formation of dense bone structures around them.

Effects of genotype, gestation length and litter size on the birth weight, litter weight, pre- and post-weaning weight of crossbred kits

BackgroundPerformance of rabbit is hinged on many factors of which the birth weights, gestation length and the litter size are most important. Linear body traits provide vital information on the performance, productivity and carcass characteristics which could be useful tool for the improvement in genetic potentials of rabbits. Therefore, this study investigated the effects of genotype, gestation length and litter size on the birth weight, pre- and post-weaning weight of crossbred kits.ResultsFive breeds: Rex (RX), Dutch-belted (DBT), New Zealand white (NZW), Californian white (CFW) and local breed (LAB) of rabbit were used for the study. A foundation stock of 40 growing rabbits consisting of six does and two bucks were used for the crossing experiment. Genotype exerted significant influence (P < 0.01) on the litter weight at birth as well as on the body weight of the kits at 21st and 35th days. The kit kindled from mating CFWxDBT breeds had the highest mean body weight from birth (91.90 ± 9.84 g) to 35th days (368.25 ± 17.36 g), while the crosses of DBTxCFW recorded the least mean body weight from birth (74.25 ± 1.78 g) to 35th days (332.60 ± 12.54 g). Gestation length significantly (P < 0.05) influenced individual and litter birth weights, pre- and post-weaning weights of kits. Does with short gestation length (29 days) had kits with light body weight compared to those with longer period of gestation (34 days). More so, kits belonging to large litter size (7) had the lowest body weight at birth as well as 21st and 35th day (69.93 ± 1.63 g, 209.57 ± 3.70 g, 319.11 ± 9.22 g) compared to kits that belonged to small litter group size. Highly significant (P < 0.01) and the strongest phenotypic relationships were recorded between body weight at day 21 and day 35 for all crosses, while weak and negative genetic correlation (r = − 0.19) was observed between litter birth weight and individual birth weight of crossbred kits.ConclusionCrossbreeding produces offspring with better performances. Birth weight of kits is a prediction tool for the overall performance of rabbits provided the environment is uninterrupted.

Efficiency of meat-fattening rabbits farmed by different keeping technologies

In Russia, different technologies are used for keeping commercial young animals in the production of rabbit meat. The main ones are in rooms with a controlled microclimate (imported young rabbits) and sheds (domestic breeds). The aim of the study was to establish the dominant factors that determine efficiency of rabbit meat production under different keeping technologies and dry feeding. Experimental studies were conducted according to classical zootechnical methods. The experiment in the room with controlled conditions was carried out on crossbred young animals - f rom Californian and New Zealand white breeds, which were imported from France in 2010; the experiment on domestic breed - Soviet chinchilla - was carried out under shed keeping technology. During the fattening period all rabbits were fed with complete granulated compound feed with an identical ratio of nutrients: 16.0 % protein and 17.5 % fiber for crossbred rabbits; 16.4 % protein and 17.9 % fiber for Soviet chinchilla rabbits. Slaughter of Soviet chinchilla rabbits and crossbred rabbits for meat was carried out at the age of 90 and 77 days, respectively. Analysis of the dynamics of live weight showed that at the age of 45 days and at the time of slaughter crossbred young rabbits exceeded Soviet chinchilla rabbits by 204.5 g and 240.0 g, respectively. Meanwhile, the relative growth of crossbred rabbits was not much higher than this indicator in Soviet chinchilla rabbits (by 3.4 and 4.1 %, respectively). The pre-slaughter weight was also significantly higher in crossbred animals, and the carcass weight was significantly higher in Soviet chinchilla rabbits. Accordingly, in the Soviet chinchilla the slaughter yield was 9.2 % higher than that of the crossbred rabbits, that is in meat production in the Soviet chinchilla more organic matter goes into products and less to waste. This testifies to the fact that by the age of 77 days the crossbred rabbits did not realize their full meat potential. Thus, considering the increased energy costs in buildings with a controlled microclimate, both technologies for keeping commercial young rabbits have the same chances in the production of rabbit meat.

Phenotypic correlation of body weight and morphometric measurements of two breeds of rabbit

A total of one hundred (100) matured rabbit of 4 to 6 months of age with weight ranging from 1.4 to1.8 kg comprising of New Zealand White (NZW) and Dutch (DUT) breeds were used for the study to evaluate phenotypic correlation of body weight and morphometric traits. They comprise of forty-nine (49) New Zealand White rabbits (13 males and 36 females) and 51 Dutch breed comprising of 21males and 30 females. The experimental design used for the study was completely randomized design and the statistical analysis used was analysis of variance. The body weight and the morphometric traits measured were determined using digital weighing scale and flexible tape in kilograms and centimeters respectively. The data measured were body weight (BW), body length (BL), nose to shoulder length (NSL), heart girth (HG), height at withers (HW), ear length (EL), leg length (LL), tail length (TL) and height of the rabbit (HR). Positive and highly significant (p&lt;0.001) correlation was observed between body weight and body length (r=0.70**). This may indicate that selection for improvement of body weight may lead to an improvement in body length. Moderate and positive correlation (p&lt;0.01) was observed between leg length (LL) and tail length (TL) r=0.26**, nose to shoulder length and tail length 0.36** respectively. Low correlation was observed between nose to shoulder length and leg length (r=0.19**). The results revealed that increase in LL may not necessarily lead to increase in NSL. The results of this study indicated positive and highly significant (p&lt;0.001) correlations between some morphometric traits measured in Dutch and New Zealand White rabbits. This is an indication that increases in one trait may lead to an increase in the other corresponding trait for the positive correlation. Meanwhile, negative correlation was also observed in the study between body weight and height of rabbit (- 0.09), height at wither and tail length ( -0.11), heart girth and tail length (-0.08) and between heart girth and hearth at withers (-0.24). This implies that increase in one parameter led to decrease in the corresponding one. Therefore, selection for an increase in such a particular trait apparently leads to a decrease in the other corresponding trait.

Monitoring of indicators of mineral metabolism in new zealand white rabbits

The quality of livestock products depends on the mineral status of the animals. The study of mineral elements makes it possible to investigate changes in the environment and to prevent negative impacts both on the animal organism, the wellbeing of which is completely dependent on humans, and on the human organism, as the final consumer of food of animal origin. A promising direction in veterinary medicine is the development of new methods of non-invasive diagnostics for assessing the state of health and determining metabolic disorders of essential elements in the body of rabbits, because these methods will be more humane and will facilitate the work of a veterinary medicine doctor. The aim of the study was to determine the characteristics of mineral metabolism in rabbits of the New Zealand white breed by age and sex and the informativeness of the assessment of metabolism for the use of various biological materials. The studies were carried out under production conditions on 24 clinically healthy rabbits of the New Zealand White breed, of all ages and sex. For research, blood, urine, and hair were taken from the animals. The content of trace elements in biological materials was determined by the method of atomic emission spectrometry with inductively coupled plasma. A significant correlation was revealed between the content in the blood plasma of rabbits of Calcium with hair (-0.42), Manganese with hair (-0.32), Iron with hair (0.63), Zinc with hair (0.40), Copper with hair (0.39) and with urine (0.44); between the content in whole blood of rabbits of Calcium with hair (0.47) and with urine (- 0.33), Manganese with hair (-0.32); between the content of Cobalt with hair in the urine (-0.35). The dynamics of the content of Calcium, Manganese, Iron, Zinc, Cobalt, and Copper in the biological materials of rabbits depending on their age and sex was found out, which is indicated by a significant increase in the blood plasma of Calcium, Manganese, Iron, Zinc, Cobalt, and Copper in females from 70 to 240 days and a significant increase in Manganese and Zinc and a decrease in Copper in males from 70 to 90 days. The informational content of the non-invasive method for diagnosing microelementoses in rabbits has been experimentally and theoretically substantiated, and the informational content of the microelement composition of hair for biogeocoenotic diagnostics has been proved, which is appropriate for medical examination and mass research of rabbits. In the future, we plan to investigate other elements in different biological materials of rabbits, followed by an assessment of the information content of noninvasive methods for diagnosing disorders of mineral metabolism.

EFFECTS OF SEX AND GENOTYPE ON MORPHOMETRIC TRAITS OF RABBIT

A total of one hundred (100) matured rabbit of 4 – 6 month of age comprising of New Zealand White (NZW) and Dutch (DUT) breeds were used in the study. They comprised of forty nine (49) New Zealand White, thirteen (13) males and thirty six (36) females, Fifty one (51) Dutch breed comprising of twenty one (21) males and thirty (30) females. The experiment was conducted at the Livestock Teaching and Research Farm, University of Maiduguri, Borno State. Maiduguri. The management system used was intensive system and semi intensive system. By housing them in a cage based on breed and sex. Each rabbit is housed in a cage measuring 33cm x 38cm x 45cm and the cages were tagged for easy identification, measurement and weighing. The cages were slightly raised above the ground for cross ventilation and to facilitate cleaning.Body weight was measured with a digital weighing scale in kilograms and the body measurements were measured using tailor tape calibrated in centimeters. The data measured are body weight (BW), body length (BL), nose to shoulder length (NSL), heart girth (HG), height at withers (HW), ear length (EL), leg length (LL), tail length (TL) and height of the rabbit (HR). Results obtained showed that sex had no significant effect on all the morphometric data measured. Significant effect of genotypes on morphometric traits were observed on NSL, HG, HW, EL and TL with their corresponding values of 10.83, 13.57, 13.37, 14.73, 10.95 in Dutch breed and corresponding values in

Molecular genetic diversity of some rabbit breeds based on mitochondrial 16S rRNA sequences

&lt;p&gt;The present study was performed to assess the genetic variations among six rabbit breeds in Egypt based on mitochondrial 16S rRNA sequences. The length of partial mitochondrial 16S rRNA in the six rabbit breeds ranged from 546 bp to 558 bp. The sequenced regions were submitted to GenBank/NCBI under accession numbers (MW052052 - MW052057). The average content of A+T was 57% in all breeds. Among breeds, the percentages of genetic distance values were ranged from 0.000 to 0.004. The highest P-distance (0.004) was found between the New Zealand White breed and all other breeds. The results support the suitability of mitochondrial 16S rRNA for genetic diversity analysis of rabbit breeds and the applicability for future research on genetic relationships and the phylogeny of rabbit breeds.&lt;/p&gt;

UPLC-QToF Nanospray MS and NMR Analysis of Ficus sycomorus Stem Bark and Its Effects on Rabbit

In the present study, a phytochemical of Ficus sycomorus (Moraceae family) was screened, and the effect of this extract on rabbit performance indices, immunity, and carcass quality measures was determined. Ficus sycomorus samples were collected, air-dried, and extracted with 70% methanol to prepare a solution of 100 mg/mL concentration. The extract was subjected to high-resolution mass spectrometric measurements via ultra-high performance liquid chromatography-quadrupole time-of-flight-nanospray mass spectrometry (UPLC-QToF-MS) and 1H NMR analysis. Forty-eight male rabbits, one-month-old, belonging to the Blanc de Bouscat and New Zealand White breeds were selected and distributed equally in a 2 × 3 factorial trial. The rabbits within each breed received F. sycomorus extract at the dose of 0, 100, and 200 mg/kg for 60 days. Blood samples were collected and serum obtained for the detection of liver enzymes, serum lipids, and proteins. The results of UPLC-QToF-MS and molecular networking analysis revealed the presence of procyanidin B2, procyanidin A1, genistein, eriodyctiol, catechin, luteolin, biochanin A, and chlorogenic acid that might exhibit various pharmaceutical activities. However, the F. sycomorus extract reduced rabbit performance indices and carcass quality measures. In addition, this extract significantly depressed the low-density lipoprotein and triglycerides, which may indicate the antidyslipidemia effect of this extract on rabbits.

EFFECT OF DIETARY SUPPLEMENTATION WITH SEAWEED AND POLYPHENOLS MIXTURE ON ANTIOXIDANT STATUS, CONCENTRATION AND MOTILITY OF RABBIT SPERMATOZOA

In recent years, many studies have been focused on natural substances that could have effect on health of animals. We investigated effect of extract consisting mainly of polyphenols, brown algae and plant polysaccharides on the reproduction potential of male rabbits (New Zealand white breed) during 60 days long dietary experiment. The rabbits were divided into three groups. Control was fed a basal diet, whereas the second and third group were supplemented with seaweed and polyphenols mixture: T1 = 0.3% and T2 = 0.6% respectively. We observed that sperm concentration in both experimental groups increased in comparison to the control group. Results of the CASA analysis showed enhanced motility (C = 85.09±7.53%, T1 = 87.21±8.25%, T2 = 89.38±8.02%) and progressive motility (C = 74.28±12.6%, T1 = 79.07±13.89%, T2 = 81.28±11.37%) in experimental groups supplemented with combination of algae and polyphenols in comparison with the control group. While monitoring ferric reducing ability of plasma (FRAP), we found the highest value in T1 group, changes were insignificat. An increase in GPx activity was measured in experimental groups in comparison with the control group with major difference in T1 group. In experimental groups, we determined an increase in activity of superoxide dismutase (SOD) in comparison with control group, the difference was significant in T2 group (C = 0.26±0.11 U/mg TP; T2 = 0.31±0.09 U/mg TP). In conclusion, our studies suggest that dietary supplementation with brown seaweed and plant polyphenols mixture may be potentially useful for enhancement of sperm motility and protection against oxidative stress.

Вплив вітамінно-мінеральних добавки на показники антиоксидантного захисту у кролів новозеландської білої породи

Recently, scientific approaches to the classification of the antioxidant system by the mechanism of free radical peroxidation have emerged. This classification of antioxidants is based on the metabolic link to which the action of the antioxidant itself is directed. Therefore, the study of the effect of vitamin and mineral supplements on the indicators of antioxidant protection in farm animals is becoming increasingly important. The aim of this work was to study the effect of different doses of the vitamin-mineral supplement "Tekro" on the biochemical parameters of the New Zealand White breed rabbits. Scientific and economic experience on the topic of work and production verification were carried out on clinically healthy New Zealand White rabbits. The animals were fed with complete feed. Access to food and water was free. To conduct research on the farm, 4 groups of animals were formed: 1 control group, whose animals consumed the basic diet (RR); 2 research – OR with the content of vitamin and mineral supplements (VMS) "Tekro" 3.0%; 3 research – OR with the content of VMS "Tekro" 3.5%; 4 research – OR with a content of VMS "Tekro" 4.0%. The activity of antioxidant enzymes and the content of ceruloplasmin in the blood plasma and liver of rabbits were determined on the 45-th, 60-th, 75-th and 90-th days. In the blood plasma of rabbits from the control and experimental groups, a change in the activity of antioxidant defense enzymes was established. The obtained research results showed that long-term use of the vitamin-mineral supplement "Tekro" significantly positively influenced the antioxidant defense system of the animal body. The established changes in the indicators of antioxidant protection indicate the tension of balancing the prooxidant-antioxidant system of young rabbits. In particular, this phenomenon can be explained by the age-related characteristics of the formation of the antioxidant system of the growing organism of the New Zealand white breed rabbits under the influence of the vitamin-mineral supplement "Tekro". This phenomenon may be evidence of the stabilization of antioxidant processes in the blood plasma of rabbits of the experimental groups as a result of the complex effect of the optimal dose of biologically active substances of the vitamin and mineral supplement. Prospects for further research consist in a detailed study of the effect of various doses of the vitamin-mineral supplement "Tekro" on protein metabolism in the rabbit's body.

PERFORMANCE OF RABBITS FED LEUCAENA LEUCOCEPHALA AND AND CONCENTRATR BETWEEN 9TH AND 25TH WEEKS OF AGE.

Fourteen fryer male rabbit (New Zealand white and chinchilla breeds) were used for the experiment. Equal numbers of rabbits from the two breeds were used for each treatment. The rabbits were randomly Leucaena leucocephala respectively. The rabbit in the two groups were given the same amount of pelleted concentrates from a commercial feed miller and were fed to determine the effect of level of leucaena offered/intake on the growth rate of rabbits. Four fryers which were fed the same % of concentrates and Aspilia africana served as the control. Growth rate decreased at the beginning of the study followed by satisfactory growth thereafter. The control animals had a higher growth rate compared to the other two groups (P&lt;0.05. Alopecia and decreased appetite were the initial symptoms of mimosine toxicity observed, but they were soon overcome with time. Rabbits can tolerate up to 100g leucaena in their diet in addition to pelleted concentrate.

REPRODUCTIVE AND BODY WEIGHT PERFORMANCE OF THE NEW ZEALAND WHITE RABBITS IN THE HUMID TROPICS OF NIGERIA.

Fifty two litters obtained over a period of 8 months (December 1986-July 1987) from the mating of eight bucks with twenty nine does (first mating) and twenty three does (second mating) all belonging to the New Zealand White breed of rabbits were used in this analysis. Mean gestation length, number of mating to conception, litter size at birth and parturition interval were 31.6 ± 0.2 days, 1.4 ± 0.1, 5.6 ± 0.3 pups and 79.0 ± 14.5 days respectively. Litter weight at birth, 3,6 and 8 weeks of age were 230.4 ± 9.5g, 602.1 ± 35.6g, 1247.5 ± 81.5g and 1673.0 ± 112.3g respectively. Parity significantly (P &lt;0.05) affected the number of mating to conception and litter birth weight. Litter weight at all ages were influenced (P&lt;.01) by corresponding litter sizes at such ages. Sire neither had any effect on litter weight at all ages nor on any of the reproductive parameters studied. Litter size at birth was negatively correlation with gestation length (-0.08), number of matings to conception (-0.27) and average birth weight (-0.42).

Heterosis and recipocal effects for growth traits in crosses of New zealand white, Dutch and chinchilla breeds of rabbit.

Records of body weight (BW) and linear body measurement (LBMs), namely body length (BL), body width (bwh), heart girth (hg), height-at withers (HW), shoulder-to-tail drops (ST), ear lenght (EL), head-to-shoulder (HS), lenght of fore limb (LFL), lenght of hind limb (LHL) and head circumference (HC) taken on 72 kits produced through complete dialled crosses were used to estimate heterosis and recipocal effects. The crosses involved New Zealand White (NZW), Dutch (DT) and Cchinchilla (CH) breeds of rabbit. Only NZW x DT and CH x DT crosses showed heterosis for BWs, indicating that non-additive sults for all effects of genes could be important for the LBMs were generally similar. Recipocal effect was not significant (p&lt;0.05) for all traits. suggesting that any of the breeds may be used as sire or dam in planned crossesbreeding programmes.

Репродуктивные качества крольчих при использовании в составе их рационов оздоровительной добавки кормовой «Гумэл люкс»

The influence of the health-improving feed additive "Gumel Lux" on the reproductive qualities of rabbits of the New Zealand white breed was studied. The positive effect of the feed additive on the increase in the weight of the nest in okrol by 11.67% compared to the control and by 10.57% when weaning rabbits at 35 days of age was established. The safety of rabbits under the influence of the health-improving feed additive "Gumel Lux" was higher than in the control group by 4.16%, and the milk content of rabbits increased by 1.5 times, respectively.